This document relates to the technical field of (and is not limited to) permanent magnet brushless DC electric machines (with rotatable shaft and fixed stator assembly), which are controlled using angular-based triggered switching assembly in such a way that the electromechanical torque transmitted to the rotatable shaft increases with speed and method therefor.
The interaction of like poles (north or south) of two magnetic bodies results in a mechanical repulsive force between the bodies that forces them apart. While the interaction of unlike poles of two magnetic bodies results in an attractive force that pulls the bodies to each other. This basic phenomenon of magnetic attraction and repulsion can be harnessed to produce continuous mechanical energy using various arrangements of permanent magnets and electromagnets. The use of electromagnets is essential to the production of continuous mechanical energy, as their magnetic polarity can be manipulated by changing the direction of the current flow in the windings of the electromagnets. Thus, magnetic attraction and repulsion can be controlled by changing the magnetic polarity of an electromagnet to interact with either another electromagnet or permanent magnet.
It will be appreciated that there exists a need to mitigate (at least in part) at least one problem associated with the existing electric rotating machines, such as electrical motors and electrical generators (also called the existing technology). After much study of the known systems and methods with experimentation, an understanding of the problem and its solution has been identified and is articulated as follows:
The electromechanical torque developed at the shaft of a typical dc electric motor (brushed or brushless) tends to increase as the magnitude of the current that flows through its stator windings increases and vis-versa. However, as the angular speed of the shaft increases, the current in the stator windings decreases and so does the electromechanical torque developed at the shaft. This is due to the back-EMF developed across the stator windings, which tends to oppose the supply voltage and thus the magnitude of the stator current.
Based on the classic dc motor equations, electromechanical torque is highest at motor start-up and decreases linearly with the increasing speed of the shaft. Consequently, the mechanical power of a dc motor increases non-linearly from zero at start-up and reaches a maximum value at a mid-range speed, after which it reduces non-linearly towards zero.
Therefore, a dc motor is normally operated in a specific speed range to maximize its performance and electromechanical conversion efficiency.
Cogging torque is associated with brushless permanent magnet dc motors and its magnitude is dependent on angular position and periodicity per revolution based on the number of magnetic poles. Cogging torque is an undesirable component for the operation of such a motor. It is especially prominent at lower speeds, with the symptom of jerkiness. Cogging torque results in torque as well as speed ripple; however, at high speed, the moment of inertia of the rotor filters out the effect of the cogging torque. Brushless permanent magnet dc motors typically require more mechanical energy to overcome the cogging torques in order to initiate and sustain rotation.
The problem associated with known (conventional) rotating electric machines, such as electric motors, typically have peak electromechanical conversion efficiencies in the range of about 75 percent to about 80 percent (%). However, some electric motors have been known to achieve peak electromechanical conversion efficiencies of up to 95 percent (%).
To mitigate, at least in part, at least one problem associated with the existing technology (that is, the existing electric rotating machines), there is provided an apparatus. This apparatus includes (and is not limited to) a DC power module, a controller that consists of an array of switching devices that are triggered based on the angular position of a rotatable shaft and a brushless permanent magnet motor assembly consisting of a rotatable disk assembly, a rotatable shaft and stator assembly. The controller accepts power from a DC power module and energizes the electromagnets of the stator assembly in such a way to cause the permanent magnets on the rotatable disk assembly to be continuously attracted towards and repelled away from the magnetic neutral point of the ferromagnetic cores of the electromagnets of the stator assembly. The magnetic neutral point is a position adjacent to the ferromagnetic core at which a permanent magnet of the rotatable disk assembly would come rest with the controller de-energized. The stator assembly remains fixed and the rotatable disk assembly is mechanically coupled to a rotatable shaft, which is used to drive a load.
To mitigate, at least in part, at least one problem associated with the existing technology (that is, the existing electric rotating machines), there is provided a method. The method includes (and is not limited to) the sequence of energizing and de-energizing the electromagnets of the stator assembly using the controller in such a way that magnitude of the current in the windings of the electromagnets increases with the speed of the shaft and the rotatable disk assembly. Consequently, the electromechanical torque developed at the shaft is increased with speed.
To mitigate, at least in part, at least one problem associated with the existing technology (that is, the existing electric rotating machines), there is provided a method. The method includes (and is not limited to) the periodic harvesting of the energy stored in the magnetic field of the electromagnets of the stator assembly to achieve maximum electromechanical conversion efficiency of the brushless permanent magnet motor assembly at all operating speeds.
To mitigate, at least in part, at least one problem associated with the existing technology (that is, the existing electric rotating machines), there is provided (in accordance with a first major aspect) an apparatus. The apparatus includes (and is not limited to) a rotatable common (or coupled) shaft configured to be rotatable about a fixed longitudinal axis extending along the rotatable shaft. The apparatus also includes multiple disk assemblies that are mechanically coupled to a common rotatable shaft. This is done in such a way that the disk assemblies of the brushless permanent magnet motor assemblies and the common (or coupled) rotatable shaft are coaxially arranged and concurrently rotatable about a common longitudinal axis. The apparatus also includes fixed stator assemblies that are so arranged to allow magnetic interaction with the permanent magnets mounted on the disk assemblies. These disk assemblies and stator assemblies are arranged in such a way that a net cogging torque which is imparted to the common rotatable shaft is reduced.
To mitigate, at least in part, at least one problem associated with the existing technology (that is, the existing electric rotating machines), there is provided (in accordance with a second major aspect) a method. The method includes (and is not limited to) arranging multiple disk assemblies and corresponding stator assemblies about a common (or coupled) rotatable shaft configured to be rotatable about a longitudinal shaft axis extending along the common (or coupled) rotatable shaft. These disk assemblies and stator assemblies are arranged in such a way that a net cogging torque which is imparted to the rotatable shaft is reduced.
To mitigate, at least in part, at least one problem associated with the existing technology (that is, the existing rotatable electric machines), there is provided (in accordance with a second major aspect) an apparatus. The apparatus includes a rotatable common (or coupled) shaft configured to be rotatable about a longitudinal shaft axis extending along the rotatable common (or coupled) shaft. Brushless permanent magnet motor assemblies are arranged at spaced-apart positions along a rotatable common (or coupled) shaft. The brushless permanent magnet motor assemblies each have a respective rotatable disk assembly that is circumferentially shifted relative to the other rotatable disk assemblies about the longitudinal shaft axis. This is done in such a way that disk assemblies of the brushless permanent magnet motor assemblies and the rotatable common (or coupled) shaft are concurrently rotatable, and a net cogging torque, which is imparted to the rotatable common (or coupled) shaft, is reduced.
Other aspects are identified in the claims. Other aspects and features of the non-limiting embodiments may now become apparent to those skilled in the art upon review of the following detailed description of the non-limiting embodiments with the accompanying drawings. This Summary is provided to introduce concepts in simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the disclosed subject matter, and is not intended to describe each disclosed embodiment or every implementation of the disclosed subject matter. Many other novel advantages, features, and relationships will become apparent as this description proceeds. The figures and the description that follow more particularly exemplify illustrative embodiments.
The non-limiting embodiments may be more fully appreciated by reference to the following detailed description of the non-limiting embodiments when taken in conjunction with the accompanying drawings, in which:
The drawings are not necessarily to scale and may be illustrated by phantom lines, diagrammatic representations and fragmentary views. In certain instances, details unnecessary for an understanding of the embodiments (and/or details that render other details difficult to perceive) may have been omitted. Corresponding reference characters indicate corresponding components throughout the several figures of the drawings. Elements in the several figures are illustrated for simplicity and clarity and have not been drawn to scale. The dimensions of some of the elements in the figures may be emphasized relative to other elements for facilitating an understanding of the various disclosed embodiments. In addition, common, but well-understood, elements that are useful or necessary in commercially feasible embodiments are often not depicted to provide a less obstructed view of the embodiments of the present disclosure.
The following detailed description is merely exemplary and is not intended to limit the described embodiments or the application and uses of the described embodiments. As used, the word “exemplary” or “illustrative” means “serving as an example, instance, or illustration.” Any implementation described as “exemplary” or “illustrative” is not necessarily to be construed as preferred or advantageous over other implementations. All of the implementations described below are exemplary implementations provided to enable persons skilled in the art to make or use the embodiments of the disclosure and are not intended to limit the scope of the disclosure. The scope may be defined by the claims (in which the claims may be amended during patent examination after filing of this application). For the description, the terms “upper,” “lower,” “left,” “rear,” “right,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the examples as oriented in the drawings. There is no intention to be bound by any expressed or implied theory in the preceding Technical Field, Background, Summary or the following detailed description. It is also to be understood that the devices and processes illustrated in the attached drawings, and described in the following specification, are exemplary embodiments (examples), aspects and/or concepts defined in the appended claims. Hence, dimensions and other physical characteristics relating to the embodiments disclosed are not to be considered as limiting, unless the claims expressly state otherwise. It is understood that the phrase “at least one” is equivalent to “a”. The aspects (examples, alterations, modifications, options, variations, embodiments and any equivalent thereof) are described regarding the drawings. It should be understood that the invention is limited to the subject matter provided by the claims, and that the invention is not limited to the particular aspects depicted and described.
In accordance with an embodiment, the apparatus includes (and is not limited to) a synergistic combination of a rotatable common shaft 102, a first rotatable electric machine 104, a second rotatable electric machine 106, a third rotatable electric machine 108, and the controller 110. It will be appreciated that although three rotatable disks are illustrated in
The rotatable common shaft 102 is mounted to a support (known and not depicted, such as a bearing assembly) configured to support rotational movement of the rotatable common shaft 102.
It will be appreciated that the bearing assembly may include a mechanical bearing assembly (and any equivalent thereof) and/or a magnetic bearing assembly (and any equivalent thereof). It will also be appreciated that an external mechanical impulse (generated by a starter assembly) may be required to initiate rotation of the rotatable common shaft 102 although the controller may also be configured to start the motor through the start up sequence 350 set out in
The starter assembly consists of a rotatable electromechanical component (a commercially available product similar to that used to start the engine of a conventional motor vehicle) that, when or once activated with an electrical pulse, causes a rotatable electromechanical component to mechanically couple onto the rotatable common shaft 102 thereby initiating the rotation of the rotatable common shaft 102. The starter assembly is so configured to mechanically disengage the rotatable electromechanical component from the rotatable common shaft 102 at a predetermined speed of rotation. After the starter assembly is disengaged from the rotatable common shaft 102, the rotation of the rotatable common shaft 102 is maintained and controlled using the controller 110 and the first electric-machine interface module 114, the second electric-machine interface module 116 and the third electric-machine interface module 118.
The first disk assembly 134 of the first rotatable electric machine 104 is affixed to the rotatable common shaft 102. This is done in such a way that the first disk assembly 134 and the rotatable common shaft 102 are rotatable together. For simplifying the view of the apparatus, the entirety of the first rotatable electric machine 104 is not fully depicted in
The second disk assembly 136 of the second rotatable electric machine 106 is affixed to the rotatable common shaft 102. This is done in such a way that the second disk assembly 136 and the rotatable common shaft 102 are rotatable together. For simplifying the view of the apparatus, the entirety of the second rotatable electric machine 106 is not fully depicted in
The third disk assembly 138 of the third rotatable electric machine 108 is affixed to the rotatable common shaft 102. This is done in such a way that the third disk assembly 138 and the rotatable common shaft 102 are rotatable together. For simplifying the view of the apparatus, the entirety of the third rotatable electric machine 108 is not fully depicted in
The controller 110 is configured to interface with (electrically connect with) the first rotatable electric machine 104, the second rotatable electric machine 106, and the third rotatable electric machine 108.
In accordance with an embodiment, the controller 110 may be called a computer system having a processor. The controller 110 is configured to interface with a memory assembly 111 that is configured to tangibly receive and store a program 113. The program 113 is read by the controller 110, and the controller 110 is configured to execute tasks in response to reading the program 113. In accordance with an alternative embodiment, the controller 110 includes application-specific integrated circuits (ASIC) configured to operate or execute specific operations. The ASIC includes an integrated circuit (IC) customized (configured) for a particular use or for a general-purpose use.
Preferably, the controller 110 is configured to interface with (electrically connect with) the coil pairs of the first rotatable electric machine 104, the second rotatable electric machine 106, and the third rotatable electric machine 108 (via an interface module or interface circuit). The controller 110 is configured to control, in use, the precisely timed activation of the coil pairs of the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108 to ensure optimum (A) torque at the rotatable common shaft 102, and (B) power generation associated with the first rotatable electric machine 104 and the third rotatable electric machine 108. The disk assemblies of the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108 are mechanically shifted in accordance with
Generally, the cogging torque opposes the electromechanical force generated by a rotating electric machine at least 50 percent of the time (that is, 50 percent of each rotation cycle of an electric rotating machine).
It will be appreciated that the use of two or more of the rotatable disk assemblies mounted to the rotatable common shaft 102, in use, may reduce or cancel the cogging torque (cogging force).
It will be appreciated that the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108, by virtue of their relative mechanical arrangement (a relative angular displacement that exists between the disk assemblies of the rotatable electric machines, as depicted, for instance, in
It will be appreciated that the embodiment as depicted in
In accordance with a preferred embodiment, the apparatus is adapted such that the first rotatable electric machine 104 includes the first disk assembly 134 affixed to the rotatable common shaft 102. The second rotatable electric machine 106 includes the second disk assembly 136 affixed to the rotatable common shaft 102. The third rotatable electric machine 108 includes the third disk assembly 138 affixed to the rotatable common shaft 102. The first disk assembly 134, the second disk assembly 136, and the third disk assembly 138 are spaced apart from each other.
In accordance with a preferred embodiment, the apparatus is adapted such that the first disk assembly 134 includes a first magnet collection 144 (a collection of spaced-apart permanent magnets). The second disk assembly 136 includes a second magnet collection 146 (a collection of spaced-apart permanent magnets). The third disk assembly 138 includes a third magnet collection 148 (a collection of spaced-apart permanent magnets).
In accordance with a preferred embodiment, the apparatus is adapted such that the first rotatable electric machine 104 includes a first stationary electromagnetic coil pair collection 124 (a collection of spaced-apart coil pairs). The second rotatable electric machine 106 includes a second stationary electromagnetic coil pair collection 126 (a collection of spaced-apart coil pairs). The third rotatable electric machine 108 includes a third stationary electromagnetic coil pair collection 128 (a collection of spaced-apart coil pairs).
In accordance with a preferred embodiment, the apparatus is adapted such that the controller 110 is configured to interface with the first rotatable electric machine 104 via a first electric-machine interface module 114. The first electric-machine interface module 114 is configured to electrically connect with the first stationary electromagnetic coil pair collection 124. The controller 110 is configured to interface with the second rotatable electric machine 106 via a second electric-machine interface module 116. The second electric-machine interface module 116 is configured to electrically connect with the second stationary electromagnetic coil pair collection 126. The controller 110 is configured to interface with the third rotatable electric machine 108 via a third electric-machine interface module 118. The third electric-machine interface module 118 is configured to electrically connect with the third stationary electromagnetic coil pair collection 128.
In accordance with a preferred embodiment, the apparatus is adapted such that the first rotatable electric machine 104 includes a first electric generator assembly 204. The second rotatable electric machine 106 includes an electric motor assembly 206. The third rotatable electric machine 108 includes a second electric generator assembly 208. The electric motor assembly 206 is positioned between the first electric generator assembly 204 and the second electric generator assembly 208. It will be appreciated that this arrangement of the embodiment is arbitrary, and does not provide an advantage over any other arrangement of the embodiment.
In accordance with a preferred embodiment, the apparatus is adapted such that the first electric-machine interface module 114 includes a first generator interface module 214 configured to electrically interface with the first electric generator assembly 204. The second electric-machine interface module 116 includes an electric motor interface module 216 configured to electrically interface with the electric motor assembly 206. The third electric-machine interface module 118 includes a second generator interface module 218 configured to electrically interface with the second electric generator assembly 208.
In accordance with a preferred embodiment, the apparatus is adapted such that the first electric-machine interface module 114 is electrically connected to each of the coil pairs (also called electromagnets) of the first rotatable electric machine 104, such as the first stationary electromagnetic coil pair collection 124 of the first rotatable electric machine 104. It will be appreciated that a single coil pair is depicted for the first stationary electromagnetic coil pair collection 124 for the sake of clarifying the view of the embodiment as depicted in
In accordance with a preferred embodiment, the apparatus is adapted such that the second electric-machine interface module 116 is electrically connected to each of the coil pairs (also called electromagnets) of the second rotatable electric machine 106, such as the second stationary electromagnetic coil pair collection 126 of the second rotatable electric machine 106. It will be appreciated that a single coil pair (also called electromagnets) is depicted for the second stationary electromagnetic coil pair collection 126 for the sake of clarifying the view of the embodiment as depicted in
In accordance with a preferred embodiment, the apparatus is adapted such that the third electric-machine interface module 118 is electrically connected to each of the coil pairs (also called electromagnets) of the third rotatable electric machine 108, such as a third stationary electromagnetic coil pair collection 128 of the third rotatable electric machine 108. It will be appreciated that a single coil pair is depicted for the third stationary electromagnetic coil pair collection 128 for the sake of clarifying the view of the embodiment as depicted in
Preferably, each of the first stationary electromagnetic coil pair collection 124, the second stationary electromagnetic coil pair collection 126 and the third stationary electromagnetic coil pair collection 128 includes a ferromagnetic core 129. Preferably, the ferromagnetic core 129 has a relatively high magnetic permeability, low magnetic hysteresis loss and low eddy-current loss. More preferably, the magnetic hysteresis BH (the magnetic flux density versus the magnetic field strength) curve of the ferromagnetic core 129 has low coercivity and high remnant flux density as illustrated in
Preferably, the diameter of the ferromagnetic core 129 (of the first stationary electromagnetic coil pair collection 124, the second stationary electromagnetic coil pair collection 126 and the third stationary electromagnetic coil pair collection 128) is (respectively) about (approximately) the same diameter as the permanent magnets of the first magnet collection 144, the permanent magnets of the second magnet collection 146 and the permanent magnets of the third magnet collection 148. It will be appreciated that the size, geometry and magnetic strength of the permanent magnets of the first magnet collection 144, the second magnet collection 146 and the third magnet collection 148 should, preferably, be the same.
Preferably, the ferromagnetic cores 129 (of the first stationary electromagnetic coil pair collection 124, the second stationary electromagnetic coil pair collection 126 and the third stationary electromagnetic coil pair collection 128) are respectively coaxially offset from the permanent magnets of the first magnet collection 144, the permanent magnets of the second magnet collection 146 and the permanent magnets of the third magnet collection 148. Preferably, each of the permanent magnets of the disk assemblies are spaced apart from the stationary ferromagnetic cores of the stationary electromagnet coil pairs by an air gap (a relatively small air gap) and a coaxial offset. There is a coaxial offset between the ferromagnetic cores 129 (of the first stationary electromagnetic coil pair collection 124, the second stationary electromagnetic coil pair collection 126 and the third stationary electromagnetic coil pair collection 128) and the permanent magnets of the first magnet collection 144, the permanent magnets of the second magnet collection 146 and the permanent magnets of the third magnet collection 148. The coaxial offset is clearly depicted in, for instance,
In accordance with a preferred embodiment, the apparatus is adapted such that a battery module 112 is electrically interfaced with the controller 110. The controller 110 is configured to interface with, and control operation of, the battery module 112. The battery module 112 is configured to provide electrical energy to the first electric-machine interface module 114, the second electric-machine interface module 116 and the third electric-machine interface module 118 (when needed). The battery module 112 is configured to electrically connect with the rotatable electric machines (104, 106, 108) in such a way that the battery module, in use, interacts with coil pairs of the rotatable electric machines (104, 106, 108). The controller 110 is configured to interface with, and control operation of, the battery module in such a way that: (A) the battery module 112, in use, provides electrical power to the rotatable electric machines (104, 106, 108) in such a way that any electrical power that is provided to the rotatable electric machines (104, 106, 108), in use, urges rotation of the rotatable electric machines (104, 106, 108), and (B) the battery module 112, in use, receives electrical power from the stored energy in the rotatable electric machines (104, 106, 108) in such a way that the electrical power that is provided by the stored energy in the rotatable electric machines (104, 106, 108), in use, charges the battery module 112 as needed.
In accordance with a preferred embodiment, the apparatus further includes an angular encoder 115 configured to be coupled to the rotatable common shaft 102, and interfaced or electrically connected (directly or indirectly) to the controller 110. The angular encoder 115 is configured to provide, in use, an angular position (angular displacement) of the rotatable common shaft 102 to the controller 110.
In accordance with a preferred embodiment, the controller 110 is interfaced with a memory assembly 111. A program 113 is tangibly stored in the memory assembly 111. The program 113 includes coded instructions (programmed coded instructions) that are configured to be readable by (and executable by) the controller 110. The instructions, in use, urge the controller 110 to perform predetermined operations. The memory assembly 111 is a device configured to store the program 113 having coded instructions that are readable by and executable by the controller 110. The controller 110 is configured to read the coded instructions (from the memory assembly 111), and execute the instructions that urge the controller 110 to read, for instance, the encoder position (angular displacement of the rotatable common shaft 102) from the angular encoder 115 (that is operatively connected to the controller 110), and then write the encoder position to the memory assembly 111. For instance, the controller 110 is configured to read coded instructions that instruct the controller 110 to (A) read the voltage sensor assembly Vcon1 (depicted in
Electrical communication between the controller 110 and the battery module 112 is also bi-directional as the controller 110 reads the status of the batteries in the battery module 112, and also outputs digital states to the switches of the battery module 112 based on the status of the batteries. Electrical communication between the controller 110 and the first generator interface module 214, the electric motor interface module 216 and the second generator interface module 218 is unidirectional. That is, the controller 110 is configured to write the digital status to (or to control the state of) the controllable switches that are associated with (A) the first generator interface module 214, (B) the electric motor interface module 216, and (C) the second generator interface module 218 based on the encoder position (which was provided by the angular encoder 115) that is stored in the memory assembly 111.
Preferably, the controller 110 is configured to interface with the rotatable electric machines. The controller 110 is configured to prevent electromechanical retardation (or braking) of the rotatable common shaft 102 when (A) a current is flowing in the stationary electromagnet coil windings of the rotatable electric machines, and (B) the rotatable common shaft 102 is rotated.
Preferably, the controller 110 is configured to periodically recycle any stored energy in the rotatable electrical machines for any one of: (A) supplementing the electrical energy supplied from a DC source (such as the battery module 112 as depicted in
To mitigate, at least in part, at least one problem associated with the existing technology, there is provided (in accordance with a major aspect) an apparatus. The apparatus includes a rotatable common shaft 102 configured to be rotatable about a longitudinal shaft axis 103 extending along the rotatable common shaft 102. Rotatable electric machines are arranged on the rotatable common shaft 102 in such a way that the disk assemblies of the rotatable electric machines and the rotatable common shaft 102 are concurrently rotatable. The disk assemblies of the rotatable electric machines are arranged on the rotatable common shaft 102 in such a way that a net cogging force 900, which is generated by the rotatable electric machines, and which is imparted to the rotatable common shaft 102, is reduced.
In view of the foregoing, there is provided (in accordance with a major aspect) a method. The method includes arranging rotatable electric machines on a rotatable common shaft 102 configured to be rotatable about a longitudinal shaft axis 103 extending along the rotatable common shaft 102. This is done in such a way that (A) disk assemblies of the rotatable electric machines and the rotatable common shaft 102 are concurrently rotatable, and (B) a net cogging force 900, which is generated by the rotatable electric machines, and which is imparted to the rotatable common shaft 102, is reduced.
In summary, the apparatus includes the rotatable common shaft 102 configured to be rotatable about a longitudinal shaft axis 103 extending along the rotatable common shaft 102. The disk assemblies of the rotatable electric machines are arranged on (preferably affixed to) the rotatable common shaft 102. This is done in such a way that disk assemblies of the rotatable electric machines and the rotatable common shaft 102 are concurrently rotatable. The rotatable electric machines are arranged on the rotatable common shaft 102 in such a way that a net cogging force 900, which is generated by the rotatable electric machines, and which is imparted to the rotatable common shaft 102, is reduced.
In summary, the method for operating the rotatable electric machines includes arranging the rotatable electric machines on the rotatable common shaft 102, which is configured to be rotatable about a longitudinal shaft axis 103 extending along the rotatable common shaft 102. This is done in such a way that (A) disk assemblies of the rotatable electric machines and the rotatable common shaft 102 are concurrently rotatable, and (B) a net cogging force 900, which is generated by the rotatable electric machines, and which is imparted to the rotatable common shaft 102, is reduced.
Referring to the embodiment as depicted in
In accordance with a preferred embodiment, the second rotatable electric machine 106 is configured (used) to rotate the rotatable common shaft 102 (the second rotatable electric machine 106 is considered the prime mover of the rotatable common shaft 102), and the first rotatable electric machine 104 and the third rotatable electric machine 108 are driven by virtue of being rigidly coupled to the rotatable common shaft 102. It will be appreciated that the first rotatable electric machine 104 and the third rotatable electric machine 108 may also be configured to rotate the rotatable common shaft 102 when operated as either electric motors or electric generators. It will be appreciated that the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108 operate together (cooperate) to reduce the net cogging torque transmitted to the rotatable common shaft 102 to preferably zero or close to zero.
Referring to the embodiment as depicted in
Tc1 is generated by the first rotatable electric machine 104 (or the first electric generator assembly 204 of
Tc2 is generated by the second rotatable electric machine 106 (or the electric motor assembly 206 of
Tc3 is generated by the third rotatable electric machine 108 (or the second electric generator assembly 208 of
The angle θ of the rotatable common shaft 102 represents the displacement from a fixed starting position and varies from 0 degrees to 360 degrees for a complete revolution of the rotatable common shaft 102.
Tm is the instantaneous electromechanical torque transmitted to the rotatable common shaft 102 by the first rotatable electric machine 104. It will be appreciated that Tm may also be the algebraic sum of the instantaneous electromechanical torques transmitted to the rotatable common shaft 102 by the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108.
T is the peak cogging torque acting on the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108.
Tnet is the net torque acting on the rotatable common shaft 102, and Tnet=Tm+Tc1+Tc2+Tc3.
Tcnet is the net cogging torque acting on the rotatable common shaft 102 due to the cogging torques generated by the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108, which preferably is zero (or near zero).
Ac is the equiangular displacement between the stationary electromagnetic coil windings (coil pairs) about the longitudinal shaft axis 103. Am is the equiangular displacement between the permanent magnets about the longitudinal shaft axis 103. For the embodiment presented in
It is understood that m=360 degrees/(Ac−Am).
It is appreciated that the “m” above is the coefficient of the angular displacement θ of the rotatable common shaft 102 and represents the number of cycles of the cogging torque acting on the rotatable disk assemblies per revolution of the rotatable common shaft 102.
N is the number of disk assemblies mounted to the rotatable common shaft 102 (which is three for the embodiment as depicted in
The angular shift (AS) is the circumferential angular shift between the disk assemblies of the rotatable electric machines relative to the longitudinal shaft axis 103 of the rotatable common shaft 102, and is computed using the formula: AS=absolute value (Am−Ac)/N.
For the embodiment presented in
For the embodiment as depicted in
In accordance with the embodiments as depicted in
In accordance with the embodiments as depicted in
It will be appreciated that Tc1, Tc2 and Tc3 are sinusoidal in nature. The algebraic sum of the cogging torque, Tnet, is zero (preferably) due to the circumferential angular shift between the first disk assembly 134, the second disk assembly 136 and the third disk assembly 138. The circumferential angular shift (also called a relative circumferential phase shift, a relative circumferential mechanical phase shift, or a mechanical phase shift, or any equivalent thereof) between the first disk assembly 134, the second disk assembly 136 and the third disk assembly 138 is depicted in
The rotatable electric machines are arranged on the rotatable common shaft 102 in such a way that a relative mechanical phase shift is maintained as the rotatable electric machines are rotated.
To cancel (reduce or eliminate) the net cogging force, multiple disk assemblies (that is, of the rotatable electric machines) may be mounted to the rotatable common shaft 102, in which each of the disk assemblies are mounted or arranged on the rotatable common shaft 102; this is done in such a way that there is an angular shift between the first disk assembly 134 of the first rotatable electric machine 104, the second disk assembly 136 of the second rotatable electric machine 106, and the third disk assembly 138 of the third rotatable electric machine 108.
The following formula is used to compute Tcnet=(Tc1+Tc2+Tc3).
Tcnet=T sin(mθ)+T sin(mθ−120 degrees)+T sin(mθ−240 degrees).
This trigonometric equation can be manipulated and reduced to show that Tcnet=0.
Tnet (net torque acting on the rotatable common shaft 102)=Tm (torque generated by the second rotatable electric machine 106 or by the electric motor assembly 206)+Tcnet=Tm+0=Tm.
Referring to the embodiment as depicted in
In accordance with the embodiment as depicted in
It will be appreciated that the embodiment as depicted in
Referring to the embodiment as depicted in
It will be appreciated that the embodiment as depicted in
In accordance with the embodiment as depicted in
In accordance with the embodiment as depicted in
It will be appreciated that the embodiment as depicted in
Referring to the embodiment as depicted in
The second magnet collection 146 includes spaced apart magnets (preferably, spaced-apart permanent magnets). The second magnet collection 146 includes a quantity of six magnet assemblies. Preferably, the second magnet collection 146 includes a first magnet assembly 146A, a second magnet assembly 146B, a third magnet assembly 146C, a fourth magnet assembly 146D, a fifth magnet assembly 146E, and a sixth magnet assembly 146F.
In accordance with the embodiment as depicted in
In accordance with the embodiment as depicted in
In accordance with the embodiment as depicted in
In accordance with the embodiment as depicted in
In accordance with embodiments as depicted in
In summary, the rotatable common shaft 102 is configured to be rotatable about the longitudinal shaft axis 103 extending along the rotatable common shaft 102. Rotatable electric machines (104, 106, 108) are arranged at spaced-apart positions along the rotatable common shaft 102. The rotatable electric machines (104, 106, 108) each have a respective disk assembly (134, 136, 138) that is circumferentially shifted relative to the other rotatable disk assemblies (134, 136, 138) about the longitudinal shaft axis 103. The respective disk assembly (134, 136, 138) remains circumferentially shifted relative to the other rotatable disk assemblies (134, 136, 138) while the respective disk assembly (134, 136, 138) are rotated about the longitudinal shaft axis 103. This is done in such a way that: (A) disk assemblies of the rotatable electric machines (104, 106, 108) and the rotatable common shaft 102 are concurrently rotatable; and (B) the net cogging force 900, which is generated by the rotatable electric machines (104, 106, 108), and which is imparted to the rotatable common shaft 102, is reduced.
In accordance with embodiments as depicted in
It will be appreciated that the circumferential offset angle may apply to either the rotatable disk assemblies or the stationary coil pair collections. In other words, (A) the rotatable disks respectively correspond to the first disk assembly 134, (B) the second disk assembly 136 and the third disk assembly 138 may be geometrically aligned, (C) the set of first stationary electromagnetic coil pair collection 124, and (D) the second stationary electromagnetic coil pair collection 126 and the third stationary coil pair collection are circumferentially shifted relative to each other.
It will be appreciated that the four degrees circumferential offset angle is applicable for the embodiment of the apparatus having six spaced-apart permanent magnets and five coil pairs.
For the embodiment presented in
The circumferential offset angle is represented by As. As equals the absolute value (Am−Ac)/N.
For the embodiment as depicted in
Referring to the embodiment as depicted in
It will be appreciated that there is a coaxial offset between the ferromagnetic cores of the coil pairs (coil windings) and the permanent magnets of the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108.
Preferably, demagnetization of the stationary ferromagnetic cores of the stationary electromagnet coil pairs of the rotatable electric machines occurs at a point where the stationary ferromagnetic cores and the permanent magnets of the disk assemblies are in alignment at the magnetic neutral point.
Preferably, the stationary ferromagnetic cores of the stationary electromagnet coil windings of the rotatable electric machines are configured to (A) achieve saturated magnetic flux with minimal electrical power input from the DC source, (B) maintain a high remnant magnetic flux (preferably greater than 70% of the saturated magnetic flux), (C) require minimal electrical power input from the DC source to demagnetize, and (D) have relatively low hysteresis and eddy current losses.
Preferably the hysteresis curve for the ferromagnetic cores should be as depicted in
Preferably, a remnant magnetic flux in the stationary ferromagnetic cores (of the stationary electromagnet coil pairs of the rotatable electric machines 104, 106, 108) is used to maximize a magnetic attraction force of the permanent magnets of the disk assemblies (134, 136, 138) as the permanent magnets of the disk assemblies (134, 136, 138) rotate towards the stationary electromagnet coil pairs.
Preferably, just enough current is permitted to flow in the stationary electromagnet coil pairs (coil windings) to maximize a magnetic repulsive force on the permanent magnets (of the disk assemblies 134, 136, 138) as the permanent magnets of the disk assemblies (134, 136, 138) rotate away from between the stationary electromagnet coil pairs. Preferably, the current flow in the coil pairs (that is, the stationary electromagnet coil windings) should cause the magnetic flux in the stationary ferromagnetic cores to just reach magnetic saturation. For the case where the current is allowed to exceed this threshold value, then the efficiency of the apparatus may suffer.
It will be appreciated by one skilled in the art that the careful coordination of the current that allowed to flow in the windings of the electromagnets pairs of the stationary electromagnet pair collection 124 as the permanent magnets of the rotatable disk assembly 134 approach and depart the magnetic neutral point results in the torque versus speed variation as depicted in
Preferably, the energy stored in a magnetic field of the stationary electromagnet coil windings is harvested and reused to aid in the magnetic propulsion of the permanent magnets of the disk assemblies between the stationary electromagnet coil windings.
Generally, the electromechanical torque acting on the disk assemblies (134, 136, 138) of the rotatable electric machines (104, 106, 108) is a function of the remnant magnetic flux in the electromagnet coil pairs of the rotatable electric machines (104, 106, 108), the electrical power drawn from the DC input source (such as the DC/DC converter module 317), the induced emf across the terminals of the electromagnet coil pairs of the rotatable electric machines as shown in
It will be appreciated that the cross-sectional profiles of the ferromagnetic core 129 and the permanent magnets of the first magnet collection 144 may be different from each other (if so desired).
In accordance with the embodiment as depicted in
Referring to the embodiment as depicted in
The second stationary electromagnetic coil pair collection 126 includes spaced-apart coil pairs positioned on opposite sides of the second disk assembly 136. The spaced-apart coil pairs are each positioned axially equidistant from the surface (plane) of the second disk assembly 136. The centers of the spaced-apart coil pairs are positioned circumferentially equiangular relative to the center of the second disk assembly 136. In accordance with a preferred embodiment, the second stationary electromagnetic coil pair collection 126 includes the first stationary coil pair 126A, the second stationary coil pair 126B, the third stationary coil pair 126C, the fourth stationary coil pair 126D, and the fifth stationary coil pair 126E.
The third stationary electromagnetic coil pair collection 128 includes spaced-apart coil pairs positioned on opposite sides of the third disk assembly 138. The spaced-apart coil pairs are each positioned axially equidistant from the surface (plane) of the third disk assembly 138. The centers of the spaced-apart coil pairs are positioned circumferentially equiangular relative to the center of the third disk assembly 138. In accordance with a preferred embodiment, the third stationary electromagnetic coil pair collection 128 includes the first stationary coil pair 128A, the second stationary coil pair 128B, the third stationary coil pair 128C, the fourth stationary coil pair 128D, and the fifth stationary coil pair 128E.
The first magnet collection 144 includes spaced-apart magnets supported by the first disk assembly 134 in such a way that the opposite sides (poles) of the magnets are oriented coaxially relative to the rotatable common shaft 102, and have equal radial spacing from the axis of the rotatable common shaft 102. The spaced-apart magnets are each positioned circumferentially equidistant and radially from the center of the first disk assembly 134. The centers of the spaced-apart magnets are positioned equiangular relative to the center of the first disk assembly 134. In accordance with a preferred embodiment, the first magnet collection 144 includes the first magnet assembly 144A, the second magnet assembly 144B, the third magnet assembly 144C, the fourth magnet assembly 144D, the fifth magnet assembly 144E, and the sixth magnet assembly 144F.
The second magnet collection 146 includes spaced-apart magnets supported by the second disk assembly 136 in such a way that the opposite sides of the magnets are oriented coaxially relative to the rotatable common shaft 102, and have equal radial spacing from the axis of the rotatable common shaft 102. The spaced-apart magnets are each positioned circumferentially equidistant and radially from the center of the second disk assembly 136. The centers of the spaced-apart magnets are positioned equiangular relative to the center of the second disk assembly 136. In accordance with a preferred embodiment, the second magnet collection 146 includes the first magnet assembly 146A, the second magnet assembly 146B, the third magnet assembly 146C, the fourth magnet assembly 146D, the fifth magnet assembly 146E, and the sixth magnet assembly 146F.
The third magnet collection 148 includes spaced-apart magnets supported by the third disk assembly 138 in such a way that the opposite sides of the magnets are oriented coaxially relative to the rotatable common shaft 102, and have equal radial spacing from the axis of the rotatable common shaft 102. The spaced-apart magnets are each positioned circumferentially equidistant and radially from the center of the third disk assembly 138. The centers of the spaced-apart magnets are positioned equiangular relative to the center of the third disk assembly 138. In accordance with a preferred embodiment, the third magnet collection 148 includes the first magnet assembly 148A, the second magnet assembly 148B, the third magnet assembly 148C, the fourth magnet assembly 148D, the fifth magnet assembly 148E, and the sixth magnet assembly 148F.
Referring to the embodiment as depicted in
In accordance with the general layout as depicted in
The electric motor interface module 216 is configured to electrically interface with the first stationary coil pair 126A, the second stationary coil pair 126B, the third stationary coil pair 126C, the fourth stationary coil pair 126D, and the fifth stationary coil pair 126E. Preferably, the electric motor interface module 216 includes: (A) CP-A motor interface module 316A configured to electrically interface with the first stationary coil pair 126A (that is, configured for use with the coil pair A or CP-A), (B) CP-B motor interface module 316B configured to electrically interface with the second stationary coil pair 126B (that is, configured for use with the coil pair B or CP-B), (C) CP-C motor interface module 316C configured to electrically interface with the third stationary coil pair 126C (that is, configured for use with the coil pair C or CP-C), (D) CP-D motor interface module 316D configured to electrically interface with the fourth stationary coil pair 126D (that is, configured for use with the coil pair D or CP-D), and (E) CP-E motor interface module 316E configured to electrically interface with the fifth stationary coil pair 126E (that is, configured for use with the coil pair E or CP-E).
The DC/DC converter module 317 (direct current to direct current converter module) is a known commercial product (and is therefore not described here). The DC/DC converter module 317 is configured to convert the DC (direct current) voltage from the battery module to a higher utilization voltage. In other words, for the case where the DC voltage from the battery module 112 is (for instance) about 48 volts DC (Direct Current), the DC/DC converter module 317 may convert that voltage to a utilization DC voltage of about (for instance) 100 volts or higher. The utilization of a DC voltage may be controlled either by the controller 110 or may be operated with a fixed setting (if desired). However, the advantage of a controlled utilization voltage is that it may: (A) control the starting torque of the electric motor, (B) limit the starting current of the electric motor, and/or (C) control the motor operating torque. The control of the DC utilization voltage is the preferred embodiment.
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
The controller 110 is configured to control the switches SW1A, SW2A, SW3A, and SW4A in such a way that these switches, in use, control the charging of the batteries associated with the battery module 112 by using the recovered energy from coil pair CP-A (as needed), etc. It will be appreciated that the same description may apply to the CP-B motor interface module 316B, the CP-C motor interface module 316C, the CP-D motor interface module 316D, and the CP-E motor interface module 316E (depicted in
It will be appreciated that the usage of the diodes in place of the switches is an alternative option (that is, for the switches depicted in
It will be appreciated that the CP-A motor interface module 316A (Part B) and the CP-A motor interface module 316A (Part C) cooperate with each other to charge the batteries of the battery module 112 (which is depicted in
In accordance with the embodiment as depicted in
The battery module 112 is electrically connected to each of the CP-A motor interface module 316A to the CP-E motor interface module 316E of the electric motor interface module 216. The battery module 112 is configured to accept recovered energy from CP-A, CP-B, CP-C, CP-D, and CP-E (stationary coil pairs) electrically connected to the electric motor interface module 216 (as needed). The battery module 112 is configured to provide DC (Direct Current) input power to the DC/DC converter module 317.
The DC/DC converter module 317 is electrically connected to each of the CP-A motor interface module 316A to the CP-E motor interface module 316E of the electric motor interface module 216. The DC/DC converter module 317 is configured to provide utilization DC input power to the CP-A motor interface module 316A, CP-B motor interface module 316B, CP-C motor interface module 316C, CP-D motor interface module 316D and CP-E motor interface module 316E. The DC/DC converter module 317 may be configured to increase the voltage supply by the battery module 112 to a relatively higher utilization DC voltage that is used by the electric motor interface module 216.
In accordance with the embodiment as depicted in
The DC(+) and the DC(−) terminals of the battery module 112 are electrically connected to the DC/DC converter module 317, as depicted in
Battery 1 (batt 1) and battery 2 (batt 2) of the battery module 112 may be operated in either running mode or in standby mode. The running battery provides power to the DC/DC converter module 317. The standby battery is charged from the recovered energy from coil pairs CP-A (coil pair A), CP-B (coil pair B), CP-C (coil pair C), CP-D (coil pair D) and CP-E (coil pair E) as needed. Note that battery 1 and/or battery 2 may include a single physical battery or may include a bank of batteries (if desired). For the case where the switches (computer controllable switches) CSB1, CSB2, CSB5 and CSB6 are OFF, battery 1 is electrically isolated and is neither being charged nor supplying electrical power to the DC/DC converter module 317.
For the case where the switches (computer controllable switches) CSB3, CSB4, CSB7 and CSB8 are OFF, battery 2 is electrically isolated and is neither being charged nor supplying electrical power to the DC/DC converter module 317.
The following is a disallowed state of battery 1 and battery 2: battery 1 and battery 2 cannot be operated in the standby or the running mode at the same time.
For the case where switches CSB1 and CSB2 are ON, switches CSB5 and CSB6 must be OFF, and in this operation mode, battery 1 is the standby battery and battery 2 is the running battery, and the switches CSB3 and CSB4 must be OFF, and the switches CSB7 and CSB8 must be ON.
For the case where the switches CSB3 and CSB4 are ON, switches CSB7 and CSB8 must be OFF, and in this operation mode battery 2 is the standby battery and battery 1 is the running battery, and the switches CSB1 and CSB2 are OFF, and switches CBS5 and CSB6 are ON.
Voltage sensor assembly Vcon1 and voltage sensor assembly Vcon2 are each configured to electrically communicate with the controller 110. Voltage sensor assemblies Vcon1 and Vcon2 are configured to monitor the voltages of battery 1 and battery 2, respectively. For the case where the voltage exceeds a predetermined threshold, the standby battery can either be electrically isolated, or the roles switched with the running battery. For the case where the voltage of the running battery is below a threshold value, the running battery is switched with the standby battery so that the running battery may be placed off-line and recharged.
For the case where the electrical rotating motor (such as, the second rotatable electric machine 106 or the electric motor assembly 206) is operated in the fifth motor operation mode 505 or the tenth motor operation mode 515, then battery 1 or battery 2 is available for charging, and the switches CS5 and CS6 are OFF, and the switches SW1A, SW2A, SW3A and SW4A are ON for both the positive and negative motor current transitions. For the case where neither battery 1 nor battery 2 are available for charging, then the switches CS5 and CS6 are maintained in the ON state, and the switches SW1A, SW2A, SW3A and SW4A are switched OFF.
For the case where the switches CS5 and CS6 are ON, then the switches SW1A, SW2A, SW3A and SW4A must be OFF, respectively, and vice versa.
The switches SW1A, SW2A, SW3A and SW4A may be ON at the same time. However, this state is allowed only when the switches CS5 and CS6 are OFF.
The above-described operation may apply to the corresponding circuits for CP-A (coil pair A), CP-B (coil pair B), CP-C (coil pair C), CP-D (coil pair D) and CP-E (coil pair E).
Referring to the embodiment as depicted in
The first motor operation mode 501 is schematically depicted in
Referring to the embodiment as depicted in
For the positive current transition in the first stationary coil pair 126A (which corresponds to the first motor operation mode 501), the digitally controllable switch CS1 is switched ON to cause a current I(1) to flow in the first stationary coil pair 126A. For the first motor operation mode 501, the switches MS1 and CS1 are ON, and the switches CS2, CS3 and CS4 are OFF. Switches CS5 and CS6 may be ON or OFF depending on the charging requirement of the batteries (battery 1 and battery 2). For the case where the batteries do not require charging, then the switches CS5 and CS6 are switched ON in the first motor operation mode 501, else (otherwise) the switches CS5 and CS6 are switched OFF.
For the negative current transition in the first stationary coil pair 126A (which corresponds to the sixth motor operation mode 511), the digitally controllable switch CS2 is switched ON to cause a current to flow in the first stationary coil pair 126A, in which the current is equal in magnitude to current I(1) but in the opposite direction.
The switches MS1 and CS2 are ON, and the switches CS1, CS3 and CS4 are OFF. Switches CS5 and CS6 may be switched OFF depending on the charging requirement of the batteries (battery 1 and battery 2). For the case where battery 1 and battery 2 do not require charging, then switches CS5 and CS6 are switched ON in the sixth motor operation mode 511, else (otherwise) switches CS5 and CS6 would be switched OFF.
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
For the second motor operation mode 502 with the positive current transition of the current flowing through the first stationary coil pair 126A, the switches MS1, CS4 and CS1 are switched ON, and the switches CS2 and CS3 are switched OFF.
For the seventh motor operation mode 512, with the negative current transition of the current flowing through the first stationary coil pair 126A, the switches MS1, CS3 and CS2 are switched ON, and the switches CS1 and CS4 are switched OFF.
Switches CS5 and CS6 may be switched ON or OFF depending on the charging requirement of the batteries (battery 1 and battery 2). For the case where the batteries do not require charging, then switches CS5 and CS6 may be switched ON in the second motor operation mode 502 and the seventh motor operation mode 512, respectively, else (otherwise) switches CS5 and CS6 would be switched OFF.
Referring to the embodiment as depicted in
Referring to
For the third motor operation mode 503, with the positive current transition of the current flowing through the first stationary coil pair 126A, the switches MS1, CS4 and CS1 are switched ON and the switches CS2 and CS3 are switched OFF.
For the eighth motor operation mode 513, with the negative current transition for the current flowing through the first stationary coil pair 126A, the switches MS1, CS3 and CS2 are switched ON and the switches CS1 and CS4 are switched OFF.
Switches CS5 and CS6 may be switched ON or OFF depending on the charging requirement of the batteries (battery 1 and battery 2). If the batteries do not require charging, then switches CS5 and CS6 may be switched ON in the third motor operation mode 503 and the eighth motor operation mode 513, respectively, else (otherwise) switches CS5 and CS6 would be switched OFF.
For the third motor operation mode 503, with the positive current transition of the current flowing through the first stationary coil pair 126A, the current I(5) in the first stationary coil pair 126A is the sum of the current I(4) from the DC voltage source and current I(3) from the charged capacitor C2.
For the eighth motor operation mode 513, with the negative current transition of the current flowing through the first stationary coil pair 126A, charged capacitor C1 and the DC voltage source (the DC/DC converter module 317) supply current to the first stationary coil pair 126A that is equal in magnitude to current I(5) but in the opposing direction to current 45), as depicted in
Referring to the embodiment as depicted in
For the positive current transition in the first stationary coil pair 124A (which corresponds to the fourth motor operation mode 504), the digitally controllable switch CS4 is switched OFF to cause a current I(6) to flow in the first stationary coil pair 124A. The current I(6) is supported only by the EMF and eventually falls to zero. For the fourth motor operation mode 504, the switches CS2, CS3 and CS4 are OFF. The magnitude of current 46) is less than or equal to current I(5) (as depicted schematically in
Referring to
For the fourth motor operation mode 504 with the positive current transition of the current flowing through the first stationary coil pair 126A, the switches MS1 and CS1 are switched ON, and the switches CS2, CS3 and CS4 are switched OFF.
For the ninth motor operation mode 514 and negative current transition for the current flowing through the first stationary coil pair 126A, the switches MS1 and CS2 are switched ON, and the switches CS1, CS3 and CS4 are switched OFF.
Switches CS5 and CS6 may be switched ON or OFF depending on the charging requirement of the batteries (battery 1 and battery 2). For the case where the batteries do not require charging, then the switches CS5 and CS6 are switched ON during the fourth motor operation mode 504 and the ninth motor operation mode 514, respectively, else (otherwise) switches CS5 and CS6 would be switched OFF.
The first motor operation mode (Mode 1+) 501A is schematically depicted in
Referring to the embodiment as depicted in
For the positive current transition in the first stationary coil pair 126A (which corresponds to the first positive motor operation mode (Mode 1+) 501A), voltage controlled switches CS1A and CS4 are switched ON at an appropriate angle (referenced to zero degree) ahead of at the instant when the permanent magnet 146A is radially aligned with coil pair 126A as illustrated in
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
Referring to
For the third positive motor operation mode (Mode 3+) 503A, voltage controlled switches CS1A and CS4 remain switched ON and power from the DC/DC Converter Module 317 and the capacitor CIA result in a further increase in current to I3 (greater in magnitude than currents I2 and I1). Current I3 results in increasing magnetization of the ferromagnetic core 129 and consequently the repulsion of the permanent magnet 146A away from the coil pair 126A. The third positive motor operation mode (Mode 3+) 503A is illustrated in
Referring to the embodiment as depicted in
Referring to
For the fourth positive motor operation mode (Mode 4+) 504A, the permanent magnet 146A is still moving away from coil pair 126A. Voltage controlled switches CS1A and CS4 are switched OFF causing the disconnection of the DC/DC Converter Module 317 from the circuit. With the voltage controlled switch CS5 is ON (could also be OFF if charging battery in Battery Module) and diode D2 is forward biased, the energy stored in the magnetic field of the coil pair 126A is transferred to the electric field of the capacitor CIA where energy is stored for use in the first negative motor operation mode (Mode 1−) 511A. This completes one-half an electrical cycle of operation. The first positive motor operation mode (Mode 4+) 504A is illustrated in
The fifth motor operation mode 505 is schematically depicted in
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
Referring to the embodiments as depicted in
Referring to
For the fifth motor operation mode 505 with the positive current transition of the current flowing through the first stationary coil pair 126A, switch CS1 is switched OFF to force the excess energy in the magnetic field of the first stationary coil pair 126A that is not consumed in the fourth motor operation mode 504 into capacitor C1. The energy stored in capacitor C1 is used on the next cycle of the second motor operation mode 502 to supplement the energy received from the DC/DC converter module 317. As the excess energy from the magnetic field of the first stationary coil pair 126A is directed to capacitor C1, the first magnet assembly 146A is propelled further along, and the current I(7) that flows in the first stationary coil pair 126A falls to zero. It will be appreciated that as the current I(7) falls to zero, the magnetic flux in the ferromagnetic core 129 of the first stationary coil pair 126A does not fall to zero due to the magnetic hysteresis of the ferromagnetic core 129.
For the fifth motor operation mode 505 and positive current transition of the current flowing through the first stationary coil pair 126A, switch MS1 is switched ON and switches CS1, CS2, CS3 and CS4 are switched OFF.
For the tenth motor operation mode 515 and negative current transition of the current flowing through the first stationary coil pair 126A, switch CS2 is switched OFF to force the excess energy in the magnetic field of the first stationary coil pair 126A that is not consumed in the ninth motor operation mode 514 into capacitor C2. The energy stored in capacitor C2 is used on the next cycle of the sixth motor operation mode 511 to supplement the energy received from the DC/DC converter module 317. As the excess energy from the magnetic field of the first stationary coil pair 126A is directed to capacitor C2, and the first magnet assembly 146A is propelled (moved) further along as the current that flows in the first stationary coil pair 126A falls to zero. It will be appreciated that as the current flowing in the first stationary coil pair 126A falls to zero, the magnetic flux in the ferromagnetic core 129 of the first stationary coil pair 126A does not fall to zero due to the magnetic hysteresis of the ferromagnetic core 129.
For the tenth motor operation mode 515 with the negative current transition of the current flowing through the first stationary coil pair 126A, switch MS1 is switched ON and switches CS1, CS2, CS3 and CS4 are switched OFF.
Switches CS5 and CS6 may be switched ON or OFF depending on the charging requirement of the batteries (battery 1 and battery 2). If the batteries do not require charging, then switches CS5 and CS6 are switched ON in the fifth motor operation mode 505 and the tenth motor operation mode 515, respectively, else (otherwise) switches CS5 and CS6 would be switched OFF.
Referring to the embodiment as depicted in
The second motor operation mode 502 may be called the motor operation mode (2+). In the second motor operation mode current I(2) flows in the first stationary coil pair 126A as capacitor C2 discharges its stored energy. Current I(2) causes an initial increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 126A that results in the propulsion of the first magnet assembly 146A away from the first stationary coil pair 126A.
The third motor operation mode 503 may be called the motor operation mode (3+). The second motor operation mode 502 occurs before the third motor operation mode 503. In the third motor operation mode current I(5) flows in the first stationary coil pair 126A as capacitor C2 continues to discharge its stored energy and supplemental energy is drawn from the DC/DC converter module 317 as diode D1 becomes forward biased. Current I(5) causes a further increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 126A that works to propel the first magnet assembly 146A further away from the first stationary coil pair 126A. In the second motor operation mode 502 and the third motor operation mode 503, the current flowing in the first stationary coil pair 126A is considered positive and has a magnitude that is greater than or equal to the current flowing in the first motor operation mode 501. Preferably, the current flowing in the first stationary coil pair 126A in the third motor operation mode 503 should be sufficient to cause the magnetic flux in the ferromagnetic core 129 to just reach magnetic saturation.
The fourth motor operation mode 504 may be called the motor operation mode (4+). In this motor operation mode, the current flowing in the first stationary coil pair 126A is considered positive and has a magnitude that is less or equal to the current that flows in the third motor operation mode 503. The energy stored in the magnetic field of the first stationary coil pair 126A, in the third motor operation mode 503, is released as electrical energy back into the first stationary coil pair 126A while continuing to propel (move) the first magnet assembly 146A away from the first stationary coil pair 126A.
The fifth motor operation mode 505 may be called the motor operation mode (5+). In this operation mode, the current flowing in the first stationary coil pair 126A is considered positive and has a magnitude that is less than or equal to the current flowing in the fourth motor operation mode 504. The excess energy, which is not consumed in the third motor operation mode 503, is directed back to capacitor C1 while continuing to propel (move) the first magnet assembly 146A away from the first stationary coil pair 126A. The current in the fifth motor operation mode 505 falls to zero, and leaves a remnant magnetic flux in the ferromagnetic core 129 as a result.
The sixth motor operation mode 511 may be called the motor operation mode (1−), which is similar to the motor operation mode (1+). In this motor operation mode, the remnant magnetic flux residing in the ferromagnetic core 129 results in the attraction of the first magnet assembly 146A toward the first stationary coil pair 126A. In the sixth motor operation mode 511, the current flowing in the first stationary coil pair 126A is considered negative.
The seventh motor operation mode 512 may be called the motor operation mode (2−) and the eighth motor operation mode 513 may be called the motor operation mode (3−), which are similar to the motor operation mode (2+) and the motor operation mode (3+), respectively. The seventh motor operation mode 512 occurs before the eighth motor operation mode 513.
In the seventh motor operation mode 512, current flows in the first stationary coil pair 126A as capacitor C1 discharges its stored energy. It will be appreciated that the current discharge from capacitor C1 is equal in magnitude to I(2) but flow in the opposite direction. This current causes an initial increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 126A that results in the propulsion of the first magnet assembly 146A away from the first stationary coil pair 126A.
In the eighth motor operation mode 513, current flow is maintained in the first stationary coil pair 126A as capacitor C1 continues to discharge its stored energy and supplemental energy is drawn from the DC/DC converter module 317 as diode D1 becomes forward biased. The total current flow from the capacitor C1 and the DC/DC converter module 317 causes a further increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 126A that works to propel the first magnet assembly 146A further away from the first stationary coil pair 126A.
In the seventh motor operation mode 512 and the eighth motor operation mode 513, the current flowing in the first stationary coil pair 126A is considered negative and has a magnitude that is greater than or equal to that in the sixth motor operation mode 511. Preferably, the current flowing in the first stationary coil pair 126A in the eighth motor operation mode should be sufficient to cause the magnetic flux in the ferromagnetic core 129 to just reach magnetic saturation.
The ninth motor operation mode 514 may be called the motor operation mode (4−), which is similar to the motor operation mode (4+). In this operation mode, the current flowing in the first stationary coil pair 126A is considered negative and has a magnitude that is less than or equal to that in the eighth motor operation mode 513. The energy stored in the magnetic field of the first stationary coil pair 126A in the ninth motor operation mode 514 is released as electrical energy back into the first stationary coil pair 126A while continuing to propel the first magnet assembly 146A away from the first stationary coil pair 126A.
The tenth motor operation mode 515 may be called the motor operation mode (5−), which is similar to the motor operation mode (5+). In this operation mode, the current flowing in the first stationary coil pair 126A is considered negative and has a magnitude that is less than or equal to that in the ninth motor operation mode 514. The excess energy that is not consumed in the ninth motor operation mode 514, is directed back to capacitor C2 while continuing to propel (move) the first magnet assembly 146A away from the first stationary coil pair 126A. The current that flows in the tenth motor operation mode 515 falls to zero and leaves a remnant magnetic flux residing in the ferromagnetic core 129 as a result.
The motor operation modes, as schematically depicted in
Referring to the embodiment as depicted in
The second positive motor operation mode (Mode 2+) 502A may be called the motor operation mode (2+). In the second positive motor operation mode current I(2) flows in the first stationary coil pair 126A due to the stored energy from capacitor CIA and the energy from the DC/DC converter module 317. Current I(2) cause a reduction in the magnetic flux in the ferromagnetic core of the first stationary coil pair 126A, which should ideally be demagnetized when the first magnet assembly 146A is aligned with the magnetic neutral point of the first stationary coil pair 126A.
The third positive motor operation mode (Mode 3+) 503A may be called the motor operation mode (3+). In the third motor operation mode current I(3) flows in the first stationary coil pair 126A as capacitor CIA continues to discharge its stored energy and supplemental energy is drawn from the DC/DC converter module 317. Current I(3) causes a reversal in the magnetic flux polarity and a subsequent increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 126A that works to propel the first magnet assembly 146A further away from the first stationary coil pair 126A. In the third positive motor operation mode 503A, the current flowing in the first stationary coil pair 126A is considered positive and has a magnitude that is greater than or equal to the current flowing in the first positive motor operation mode 501A. Preferably, the current flowing in the first stationary coil pair 126A in the third positive motor operation mode 503A should be sufficient to cause the magnetic flux in the ferromagnetic core 129 to just reach magnetic saturation.
The fourth motor positive operation mode 504A may be called the motor operation mode (4+). In this motor operation mode, the current flowing in the first stationary coil pair 126A is considered positive and has a magnitude that is less or equal to the current that flows in the third positive motor operation mode 503A. The energy stored in the magnetic field of the first stationary coil pair 126A, in the third positive motor operation mode 503A, is released as electrical energy back into capacitor CIA while continuing to propel (move) the first magnet assembly 146A away from the first stationary coil pair 126A.
The first negative motor operation mode 511A may be called the motor operation mode (1−), which is similar to the motor operation mode (1+). In this motor operation mode, the remnant magnetic flux residing in the ferromagnetic core 129 results in the attraction of the first magnet assembly 146A toward the first stationary coil pair 126A. In the first negative motor operation mode 511A, the current flowing in the first stationary coil pair 126A is considered negative.
The second negative motor operation mode 512A may be called the motor operation mode (2−).
In the second negative motor operation mode 512A, current flows in the first stationary coil pair 126A as capacitor CIA discharges its stored energy along with supplemental energy from the DC/DC converter module 317. It will be appreciated that the current discharged into the first stationary coil pair 126A from capacitor CIA and the supplemental energy from the DC/DC converter module 317 is equal in magnitude to I(2) but flows in the opposite direction. This current causes a reduction in magnetic flux in the ferromagnetic core which should ideally be demagnetized when the first magnet assembly 146A is aligned with the magnetic neutral point of the first stationary coil pair 126A.
In the third negative motor operation mode 513A, current flow is maintained in the first stationary coil pair 126A as capacitor CIA continues to discharge its stored energy and supplemental energy is drawn from the DC/DC converter module 317. The total current flow from the capacitor CIA and the DC/DC converter module 317 causes a reversal in the magnetic flux polarity and subsequent increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 126A that works to propel the first magnet assembly 146A further away from the first stationary coil pair 126A.
In the third negative motor operation mode 513A, the current flowing in the first stationary coil pair 126A is considered negative and has a magnitude that is greater than or equal to that in the first negative motor operation mode 511A. Preferably, the current flowing in the first stationary coil pair 126A in the third negative motor operation mode should be sufficient to cause the magnetic flux in the ferromagnetic core 129 to just reach magnetic saturation.
The fourth negative motor operation mode 514A may be called the motor operation mode (4−), which is similar to the motor operation mode (4+). In this operation mode, the current flowing in the first stationary coil pair 126A is considered negative and has a magnitude that is less than or equal to that in the third negative motor operation mode 513A. The energy stored in the magnetic field of the first stationary coil pair 126A in the fourth negative motor operation mode 514A is released as electrical energy back into capacitor CIA while continuing to propel the first magnet assembly 146A away from the first stationary coil pair 126A.
The motor operation modes, as schematically depicted in
The motor may be started by a start up sequence 350 as illustrated in
The controller 110 (depicted in
In operation, the controller 110 receives counter clock wise and clockwise engagement angular displacement limits about the magnetic neutral point which represent an angular degree of separation between the magnet assembly 144 and stationary coil pair. In operation, a user may input the counter clockwise and clockwise engagement angular displacement limits by any known means such as, by way of non-limiting example, dials, keypads or display screens. Optionally, the controller 110 would determine these optimal values based on the torque/speed/power requirements or to optimize motor operation and avoid undesirable operating conditions such as thermal overload or motor instability. The controller, when enabled by an on switch, or other logic circuit as are commonly known to enable operation of the apparatus, measures the angular displacement as provided by the encoder 115. If the angular position is determined to be within the counter clockwise and clockwise engagement angular displacement limits about a defined magnetic neutral point, the controller causes the electromagnetic coil pairs of stationary coil pairs assembly 124 to be engaged. Otherwise, the controller causes the coil pairs of stationary coil pairs assembly 124 to be disengaged when the magnets of disk assembly 144 leaves the region between the counter clockwise and clockwise engagement angular displacement limits about a defined magnetic neutral point.
It will be understood by those skilled in the art that the switching logic is illustrated in digital switching diagrams in
Referring to the embodiment as depicted in
The induced emf is a function of the angular displacement of the rotatable common shaft 102, the rotational speed and the number of turns of wire on the first stationary coil pair 126A. Furthermore, the induced emf is directly proportional to the product of the rotational speed and the number of turns of wire on the first stationary coil pair 126A.
It will be appreciated that the induced emf depicted in
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
A load module 415 is configured to accept electrical energy developed in coil pair A (CP-A), coil pair B (CP-B), coil pair C (CP-C), coil pair D (CP-D), and coil pair E (CP-E) to a DC electrical load (such as the load module 415) without introducing a retarding torque on (or to) the rotatable common shaft 102.
The first rotatable electric machine 104 and the third rotatable electric machine 108 are operated as (configured to operate as) the first electric generator assembly 204 and/or as the second electric generator assembly 208.
Referring to the embodiment as depicted in
The CP-A first generator interface module 414A includes the coil pair CP-A, such as the first stationary coil pair 124A, a main switch MS2, a diode D4, a diode D5, a diode D6, a diode D7, a diode D8, a capacitor C3, a capacitor C4, a digitally controllable switch CS7, a digitally controllable switch CS5, a digitally controllable switch CS9, a digitally controllable switch CS10, a digitally controllable switch CS11, a digitally controllable switch CS12, and the DC/DC converter module 317. Operation of the CP-A first generator interface module 414A is described in association with
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
The fifth generator operation mode 611 (not schematically depicted) spans across a portion of the angular rotation of the rotatable common shaft 102 (as depicted in
In the fifth generator operation mode 611, the digitally controllable switch CS8 is switched ON to cause a current to flow in the first stationary coil pair 124A. Switches MS2 and CS8 are switched ON, and the switches CS7, CS9, CS10, CS11 and CS12 are switched OFF. The current in the first stationary coil pair 124A is considered to be negative and its value (magnitude) is sufficient to reduce the remnant magnetic flux residing in the ferromagnetic core 129 to zero (about zero) for the case where the first stationary coil pair 124A and the first magnet assembly 144A are radially aligned with respect to the axis of rotation of the rotatable common shaft 102.
Switches CS11 and CS12 are used to bypass (when switched ON) the load module 415 as needed. No current is drawn from the DC/DC converter module 317 in the first generator operation mode 601 and fifth generator operation mode 611.
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
The sixth generator operation mode 612 (not schematically depicted) spans across a portion of the angular rotation of the rotatable common shaft 102 (as depicted in
Referring to the embodiment as depicted in
Switches CS11 and CS12 are used to bypass (when switched ON) the load module 415 as needed. No current is drawn from the DC/DC converter module 317 in the second generator operation mode 602 and the sixth generator operation mode 612.
Referring to the embodiment as depicted in
Referring to the embodiment as depicted in
The seventh generator operation mode 613 (not schematically depicted) spans across a portion of the angular rotation of the rotatable common shaft 102 (as depicted in
Referring to the embodiment as depicted in
Switches CS11 and CS12 are used to bypass (when switched ON) the load module 415 as needed. The third and seventh generator operation modes are the only operation modes where electrical power is drawn from the DC/DC converter module 317 (also called the DC voltage source).
Referring to the embodiment as depicted in
Referring to
Referring to the embodiment as depicted in
The eighth generator operation mode 614 (not schematically depicted) spans across a portion of the angular rotation of the rotatable common shaft 102 (as depicted in
Referring to
Referring to the embodiment as depicted in
Switches CS11 and CS12 are used to bypass (when switched ON) the load module 415 as needed. No current is drawn from the DC/DC converter module 317 in the fourth generator operation mode 604 and the eighth generator operation mode 614.
Referring to the embodiment as depicted in
The second generator operation mode 602 and the third generator operation mode 603 may be called the generator operation mode (2+) and the generator operation mode (3+), respectively. The second generator operation mode 602 occurs before the third generator operation mode 603.
In the second generator operation mode 602 current I(10) flows in the first stationary coil pair 124A as capacitor C4 discharges its stored energy. Current I(10) causes an initial increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 124A that results in the propulsion of the first magnet assembly 144A away from the first stationary coil pair 124A.
In the third generator operation mode 603, current I(13) flows in the first stationary coil pair 124A as capacitor C4 continues to discharge its stored energy with supplemental energy drawn from the DC/DC converter module 317 as diode D4 becomes forward biased. Current I(13) causes a further increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 124A that works to propel the first magnet assembly 144A further away from the first stationary coil pair 126A. Current I(13) is the sum of currents I(11) from capacitor C4 and current I(12) from the DC/DC converter module 317.
In the second generator operation mode 602 and the third generator operation mode 603, the current flowing in the first stationary coil pair 124A is considered positive, and has a magnitude that is greater than or equal to current I(9) in the first generator operation mode 601. Preferably, the current flowing in the first stationary coil pair 124A in the third generator operation mode 603 should be sufficient to cause the magnetic flux in the ferromagnetic core 129 to just reach magnetic saturation in order to maximize the energy efficiency of the system. Energy is only required from the DC/DC converter module 317 in the third generator operation mode 603.
The fourth generator operation mode 604 may be called the generator operation mode (4+). For the fourth generator operation mode 604, the current flowing in the first stationary coil pair 124A is considered positive and has a magnitude that is less than or equal to that in the third generator operation mode 603. The energy, which is developed in the magnetic field of the first stationary coil pair 124A in the third generator operation mode 603, is directed towards the load module 415 and capacitor C3 while continuing to propel (move) the first magnet assembly 144A away from the first stationary coil pair 124A. The current I(14) flowing during the fourth generator operation mode 604 falls to about zero (preferably at zero), and leaves a remnant magnetic flux residing in the ferromagnetic core 129.
The fifth generator operation mode 611 may be called the generator operation mode (1−), which is similar to the generator operation mode (1+). The remnant magnetic flux residing in the ferromagnetic core 129 results in the magnetic attraction of the first magnet assembly 144A towards the first stationary coil pair 124A. In the fifth generator operation mode 611, the current flowing in the first stationary coil pair 124A is considered negative and has a magnitude sufficient to reduce the remnant magnetic flux that resides in the ferromagnetic core 129 to about zero (preferably to zero) at the start of the sixth generator operation mode 612.
The sixth generator operation mode 612 and the seventh generator operation mode 613 may be called the generator operation mode (2−) and the generator operation mode (3−), respectively, and which are similar to the generator operation mode (2+) and the generator operation mode (3+), respectively. The sixth generator operation mode 612 occurs before the seventh generator operation mode 613.
In the sixth generator operation mode 612, current flows in the first stationary coil pair 124A as capacitor C3 discharges its stored energy. The current flowing in the first stationary coil pair 124A causes an initial increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 124A that results in the propulsion of the first magnet assembly 144A away from the first stationary coil pair 124A.
In the seventh generator operation mode 613, current flows in the first stationary coil pair 124A as capacitor C3 continues to discharge its stored energy with supplemental energy drawn from the DC/DC converter module 317 as diode D4 becomes forward biased. The current flowing in the first stationary coil pair 124A causes a further increase in magnetic flux in the ferromagnetic core of the first stationary coil pair 124A that works to propel the first magnet assembly 144A further away from the first stationary coil pair 126A. The current flowing in the first stationary coil pair 124A is the sum of currents from capacitor C3 and the current supplemented from the DC/DC converter module 317. In the sixth generator operation mode 612 and the seventh generator operation mode 613, the current flowing in the first stationary coil pair 124A is considered negative, and has a magnitude that is greater than or equal to that in the fifth generator operation mode 611. Preferably, the current flowing in the first stationary coil pair 124A in the seventh generator operation mode 613 mode should be sufficient to cause the magnetic flux in the ferromagnetic core 129 to just reach magnetic saturation in order to maximize the energy efficiency of the system. Energy is only required from the DC/DC converter module 317 in the seventh generator operation mode 613.
The eighth generator operation mode 614 may be called the generator operation mode (4−), which is similar to the generator operation mode (4+). For the eighth generator operation mode 614, the current flowing in the first stationary coil pair 124A is considered negative and has a magnitude that is less than or equal to that in the seventh generator operation mode 613. The energy in the magnetic field residing in the first stationary coil pair 124A is directed towards the load module 415 and capacitor C4 while continuing to propel the first magnet assembly 144A away from the first stationary coil pair 124A. The current that flows in the eighth generator operation mode 614 falls to zero, and leaves a remnant magnetic flux in the ferromagnetic core 129.
For the first electric generator assembly 204, the second electric generator assembly 208, and the electric motor assembly 206, it will be appreciated that the current flowing through the coil pairs are out of phase, relative to each other, by the absolute value of (Am−Ac)=abs (60−72)=12 degrees (for the depicted embodiment).
The generator operation modes, as schematically depicted in
Preferably, the circumferential angular offset of the rotatable disk assemblies cause a reduction (preferably elimination) of the net cogging torque at the rotatable common shaft 102.
Preferably, the initialization of the coil pair current uses the generated induced current without invoking retarding torques (this reduces the energy required from the source to increase the magnetic flux in the electromagnet).
Preferably, a coaxial offset between the electromagnet core of the coil pairs and the permanent magnets of the disk assemblies improves or increases the torque of the rotatable common shaft 102 (preferably to achieve maximum torque).
Preferably, the extraction and usage of the energy stored in the magnetic field of the coil pairs is used for performing mechanical work (this boosts or improves system efficiency).
Preferably, the first generator interface module 214 (depicted in
In accordance with a preferred embodiment, the apparatus includes two or more rotatable disk assemblies that are rigidly mounted (fixedly mounted) to the rotatable common shaft 102, which is rotatable about an elongated rotation axis.
Each rotatable disk assembly has an even number of permanent magnets with relatively strong magnetic fields that are embedded in the rotatable disk assemblies, and equally spaced along their periphery.
An odd number (such as three) of electromagnet pairs with high magnetic permeability, low hysteresis loss and low eddy current loss cores are rigidly mounted and arranged to interact with the magnetic field of the permanent magnets mounted to the rotatable disk assemblies as they rotate. Preferably, the ferromagnetic cores (of the coil pairs) have a high remnant magnetic flux relative to their saturated magnetic flux and low magnetic coercivity.
The rotatable disk assemblies and their corresponding electromagnet pairs are specifically arranged to eliminate (or reduce) the cogging forces that would normally be experienced in conventional electric rotating machines.
Preferably, at a minimum, external power is only required to overcome bearing friction and windage torques (frictional losses) as the rotatable common shaft 102 and the rotatable disk assemblies rotate about the rotation axis of the rotatable common shaft 102.
The apparatus is set into operation using a self-start algorithm in the controller or an initial external impulse (starting) torque that is applied to the rotatable common shaft 102 and/or the rotatable disk assemblies, and the controller 110 is subsequently engaged to maintain and control rotation of the rotatable disk assemblies.
The controller 110 is configured (programmed) to control computer-controllable switches to: (A) selectively activate and deactivate electrical power to the electromagnet pairs of the rotatable electric machines, (B) control the speed and torque of the rotatable common shaft 102, and (C) control the electrical output from the first rotatable electric machine 104 and the third rotatable electric machine 108.
The controller 110 is configured to take advantage of the ability of the electromagnets to store energy in their magnetic field and discharge the stored energy from their magnetic field while performing mechanical work. The controller 110 is also configured to take advantage of the magnetic hysteresis of the ferromagnetic core 129 to maximize the electromechanical torque at the rotatable common shaft 102 with no additional power requirement from the DC source (such as the DC/DC converter module 317).
As the electromagnets are energized, the electromagnets, in use, propel (rotate) the rotatable disk assemblies as the electromagnets magnetically interact with the magnetic field of the permanent magnets positioned on the rotatable disk assemblies, and, preferably at the same time, the electromagnets store energy in their magnetic field.
The energy stored in the magnetic field of the electromagnets is subsequently extracted as electrical energy, and is used to provide additional propulsion to the rotatable disk assemblies while the interfacing circuits are disconnected from the DC source.
The controller 110 and memory assembly 111 may require a constant source of power to operate the system.
The non-extracted energy from the electromagnets is directed to a storage device such as a capacitor (while still propelling the rotatable disk assemblies and remaining disconnected from the DC source), and is subsequently used to offset the DC source requirement on the next activation cycle of the electromagnet pairs.
Thus, the apparatus obtains only a fraction of its energy requirement from the DC source to operate, hence the improvement in efficiency over conventional rotating electric machines.
A relatively higher efficiency of the apparatus is achieved when the resistive losses in the electromagnet windings are low and the permeability and electrical resistivity of the ferromagnetic cores are relatively high.
Some of the electromagnet pairs may be used to drive the apparatus, and some to supply energy to an external electrical load.
As an electrical generator, energy is extracted from the electromagnet coil pairs without impacting the mechanical performance.
Mechanically, the axis of permanent magnets mounted to the rotatable disk assemblies, and that of the cores of the electromagnet pairs, are coaxially offset from each other in such a way that the axis of permanent magnets, in use, maximize the performance of the electric machine (electric motor and/or electric generator).
While conventional motors and generators typically require more mechanical energy to overcome the cogging forces in order to initiate and maintain rotation, the apparatus, in use, reduces or eliminates the cogging forces, and reduces the total energy required to operate the first rotatable electric machine 104, the second rotatable electric machine 106, and the third rotatable electric machine 108.
While conventional motors typically have efficiencies in the range of 75-80%, the apparatus may improve efficiency due to (A) the minimum energy requirement from the DC source while in operation, and (B) the recycling of the energy in the first rotatable electric machine 104, the second rotatable electric machine 106 and the third rotatable electric machine 108.
The apparatus may be utilized in hybrid vehicles (automobiles), wind turbines, pumps, etc.
The apparatus is powered from a direct current (DC) electrical source and operated using a controlled switching circuit to regulate speed, torque and electrical output.
Preferably, the apparatus includes two or more rotatable disk assemblies that are rigidly mounted onto a common shaft that is free to rotate about a fixed axis. Each rotatable disk assembly has an even number of permanent magnets with relatively strong magnetic fields, which are mounted to the rotatable disk assemblies, and are equally spaced along the periphery of the rotatable disk assemblies. An odd number of electromagnet pairs with high magnetic permeability and high electrical resistivity cores are rigidly mounted and arranged to interact with the magnetic field of the permanent magnets on the rotatable disk assemblies as the rotatable disk assemblies rotate.
It will be appreciated that the brushless permanent magnet motor assembly 104 may have a radial embodiment as depicted in
Unless otherwise specified, relational terms used in these specifications should be construed to include certain tolerances that the person skilled in the art would recognize as providing equivalent functionality. By way of example the term perpendicular is not necessarily limited to 90.0 degrees, but also to any slight variation thereof that the person skilled in the art would recognize as providing equivalent functionality for the purposes described for the relevant member or element. Terms such as “about” and “substantially”, in the context of configuration, relate generally to disposition, location, or configuration that is either exact or sufficiently close to the location, disposition, or configuration of the relevant element to preserve operability of the element within the invention which does not materially modify the invention. Similarly, unless specifically made clear from its context, numerical values should be construed to include certain tolerances that the person skilled in the art would recognize as having negligible importance as it does not materially change the operability of the invention. It will be appreciated that the description and/or drawings identify and describe embodiments of the apparatus (either explicitly or non-explicitly). The apparatus may include any suitable combination and/or permutation of the technical features as identified in the detailed description, as may be required and/or desired to suit a particular technical purpose and/or technical function. It will be appreciated that, where possible and suitable, any one or more of the technical features of the apparatus may be combined with any other one or more of the technical features of the apparatus (in any combination and/or permutation). It will be appreciated that persons skilled in the art would know that technical features of each embodiment may be deployed (where possible) in other embodiments even if not expressly stated as such above. It will be appreciated that persons skilled in the art would know that other options would be possible for the configuration of the components of the apparatus to adjust to manufacturing requirements and still remain within the scope as described in at least one or more of the claims. This written description provides embodiments, including the best mode, and also enables the person skilled in the art to make and use the embodiments. The patentable scope may be defined by the claims. The written description and/or drawings may help to understand the scope of the claims. It is believed that all the crucial aspects of the disclosed subject matter have been provided in this document. It is understood, for this document, that the phrase “includes” is equivalent to the word “comprising.” The foregoing has outlined the non-limiting embodiments (examples). The description is made for particular non-limiting embodiments (examples). It is understood that the non-limiting embodiments are merely illustrative as examples.
This application is a continuation in part application of U.S. patent application Ser. No. 15/294,870 filed Oct. 17, 2016 entitled “Rotatable Electric Machines”, which is incorporated by reference herein in its entirety.
Number | Date | Country | |
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Parent | 15294870 | Oct 2016 | US |
Child | 16054614 | US |