Patent Application
20230406674
The present disclosure generally relates to elevator systems, and in particular, to self-propelled elevator systems.
Traditional elevator systems implement tensions members such as ropes and/or cables, for example, to move one or more elevator cars in a hoistway. More recently, however, self-propelled elevator systems, also referred to as “ropeless” elevator systems, are being utilized in various applications (e.g., high rise buildings) where it is undesirable to implement traditional tension members to move the elevator car.
In accordance with some embodiments, a multi-phase linear induction machine included in an elevator system is provided. The multi-phase induction machine comprises at least one armature that can electrically interact with a plurality of stators. The at least one armature can be disposed in a hoistway and is configured to electrically conduct electromagnetic energy. The plurality of stators can be coupled to an elevator car that is configured to travel through the hoistway. Each of the stators are configured to conduct electrical current therethrough and to generate an electromagnetic field in response to the current. The electromagnetic field induces eddy currents that flow through the at least armature to generate a magnetic force which moves the elevator car through the hoistway.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, a first armature disposed in the hoistway and a second armature disposed in the hoistway opposite the first armature.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the first and second armatures include an electrically conductive material capable of conducting the induced electric eddy currents therethrough.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the first and second armatures extend vertically along a length of the hoistway.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein plurality of stators includes a first set of stators coupled to a first side of the elevator car and adjacent the first armature, and a second set of stators coupled to a second side of the elevator car opposite the first side of the elevator car and adjacent the second armature.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the first set of stators and the second set of stators are electrically connected to power electronics that are configured to deliver the electrical current to the first and second set of stators.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the power electronics receive battery power from a rechargeable battery, and covert the battery power into the electrical current that is delivered to the first and second set of stators.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein a controller is configured to control the power electronics and selectively control the direction of the current flow through the first and second armatures.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein current flowing through the first and second set of stators in a first direction generates an electromagnetic filed having a flux that travels in a first direction, and current flowing through the first and second set of stators in a second direction generates an electromagnetic field having a flux that travels in a second direction opposite the first direction.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the flux traveling in the first direction produces a first magnetic force that moves the elevator car through the hoistway in a first vertical direction, and wherein the flux traveling in the second direction produces a second magnetic force that moves the elevator car through the hoistway in a second vertical direction opposite the first vertical direction.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the controller invokes a recharge mode and in response to invoking the recharge mode moves the elevator car to a docking station included in the hoistway to recharge the battery.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the docking station includes a battery charger, and wherein moving the elevator car to the docking station establishes electrical transfer between the rechargeable battery and the battery charger to recharge the battery.
The multi-phase induction linear induction machine of claim 1, wherein the at least one armature and the plurality of stators establish a three-phase machine.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein two or more stators are coupled adjacent to the elevator car.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the two or more stators are configured to maintain a center car axis of the elevator car in line with a center hoistway axis of the hoistway.
In accordance with some embodiments, a method of controlling a multi-phase linear induction machine included in an elevator system is provided. The method comprises disposing at least one armature disposed in a hoistway to electrically conduct electromagnetic energy, and coupling a plurality of stators coupled to an elevator car configured to travel through the hoistway. The method further comprises conducting electrical current through each of the stators to generate an electromagnetic field, and inducing a flow of eddy currents through the at least armature in response to the electromagnetic field to generate a magnetic force that moves the elevator car through the hoistway.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the at least one armature includes a first armature disposed in the hoistway and a second armature disposed in the hoistway opposite the first armature.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the first and second armatures include an electrically conductive material capable of conducting the eddy currents therethrough.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the first and second armatures extend vertically along a length of the hoistway.
In addition to one or more of the features described above, or as an alternative, further embodiments may include a feature, wherein the plurality of stators includes a first set of stators coupled to a first side of the elevator car and adjacent the first armature, and a second set of stators coupled to a second side of the elevator car opposite the first side of the elevator car and adjacent the second armature.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, that the following description and drawings are intended to be illustrative and explanatory in nature and non-limiting.
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
At present, self-propelled elevator systems utilize a power system that employs various power electronics to facilitate the power necessary to propel an elevator car in a hoistway. These power electronics include, for example, a power inverter (e.g., as switched variable speed alternating drive (AC) motor drive) to improve performance of the power system. A switched variable speed AC motor drive, for example, typically utilizes the switching of the semiconductor switches (e.g., transistors) to create the variable voltage and variable frequency output. However, the switching of power electronic devices in a power system can cause undesirable electromagnetic interference (EMI). In general, EMI noise can be categorized into two groups: differential mode (DM) noise and common-mode (CM) noise. DM noises are conducted between phases, while CM noises are conducted together with all phases through the parasitic capacitors to the ground. CM noises can cause additional concern in motor drive applications because CM noises increase the EMI in the motor drive, which can damage the motor bearing and winding insulation.
Various non-limiting embodiments described herein avoid the CM noise concerns by providing a self-propelled elevator system that implements a multi-phase linear induction machine, which includes one or more stators coupled to the elevator car. The stators operate in response to an electromagnetic field produced by an electrically conductive armature that is coupled to an inner area of the elevator system 10 such as, for example, a wall or facade of the hoistway. The electromagnetic field energizes the stators, thereby propelling (i.e., “self-propelling) the elevator car through the hoistway. Although the system is described as a three-phase system, it should be appreciated that the system can be implemented using different phases, such as, for example, two, four, five six, etc., without departing from the scope of the present disclosure. Accordingly, sound, noise, and/or vibration of the system is virtually zero because there is no mechanical contact between the moving parts as the elevator car (also referred to as the cabin) moves through the hoistway. In addition, each car included in the elevator system is self-propelled and energized, can travel autonomously inside the hoistway to service the customer calls requested at various floor following the software protocol installed in an elevator controller.
With reference now to
As shown in
According to a non-limiting embodiment illustrated in
According to the example illustrated in
Turning now to
The first and second armatures 102a and 102b are configured to electrically conduct electromagnetic energy. In one or more non-limiting embodiments, the first and second armatures 102a and 102b include a strip or beam, or in other embodiments can include several individual strips or beams, capable of conducting eddy currents therethrough. The electrically conductive material includes, for example, metal, a magnetic material, or a combination of both. The first and second armatures 102a and 102b extend vertically along the length of the hoistway 18.
The stators 104 are configured to generate a linear traveling electromagnetic field, which in turn generates a force capable of forcing the stators to move 104 upward or downward with respect to the first and second armatures 102a and 102b. As described herein, the electromagnetic field induces eddy currents that flow through the first and second armatures 102a and 102b, which in turn generate a magnetic force capable of moving the elevator car 14 through the hoistway 18.
In one or more non-limiting embodiments, the stators 104 include a first set of stators 104a fixed to a first side 15a of the elevator car 14 and adjacent the first armature 102a, and a second set of stators 104b fixed to a second side 15b of the elevator car 14 opposite the first side 15a of the elevator car 14 and adjacent the second armature 102b. The first set of stators 104a and the second set of stators 104b are electrically connected to power electronics 106. The power electronics 106 include a power inverter (not shown) in signal communication with and a controller 108. The controller 108 is configured to control the inverter and generate current that flows through the first and second set of stators 104a and 104b. In one or more non-limiting embodiments, each stator is in signal communication with its own dedicated sub-controller (not shown), and each sub-controller is in signal communication with the controller 108. Accordingly, the sub-controllers can drive current through a respective stator and the controller 108 can independently control each of the sub-controllers to control the current flow through a respective stator.
In one or more non-limiting embodiments, the elevator car 14 further includes a rechargeable battery 110 (e.g., a lithium-ion battery) in signal communication with the power electronics 106 (e.g., the power inverter) and the controller 108. Accordingly, the power electronics 106 can receive power from the rechargeable battery 110, and covert the battery power into electrical current that is delivered to the first and second set of stators 104a and 104b. As shown in
Referring to
In one or more non-limiting embodiments, the controller 108 can selectively control the direction of the current flow through one or both of the first and second armatures 102a and 102b. In this manner, the controller 108 can generate current flow through the first and second set of stators 104a and 104b in a first direction (e.g., a downward direction) or in a second direction (e.g., an upward direction). Referring to
In one or more non-limiting embodiments, the controller 108 can control first electrical current delivered to the first set of stators 104a independent from second electrical current delivered to the second set of stators 104b. In this manner, the controller 108 can independently adjust the level of the current delivered to the first and second stators 104a and 104b to control the balance of the elevator car 14. In one or more non-limiting embodiments, the controller 108 can monitor the load distribution applied to the elevator car 14, and actively control the level of current delivered to the first set of stators 104a and/or the second set of stators 104a based on the load distribution. For example, if a greater load or weight is present at the first side 15a of the elevator car 14 with respect to the second side 15b, a greater amount of current can be delivered to the first set of stators 104a compared to the second set of stators 104b so that a greater amount of magnetic force is applied to the right side 15a of the elevator car 14. In this manner, the elevator car 14 can be balanced using, for example, two stators 104a and/or 104b which can maintain a center car axis (AC) of the elevator car 14 in line with the center hoistway axis (AH). The controller 108 can further continuously monitor the load distribution and actively control the current delivered to the first and second set of stators 104a and 104b to maintain the balance of elevator car 14 while it travels through the hoistway 18. In addition, the elevator car 14 can maintain the center car axis (AC) in line with the center hoistway axis (AH) to prevent elevator car 14 from tilting inside of the hoistway 18 during a scenario where the elevator car 14 is loaded unevenly.
Turning now to
As shown in
As described herein, various non-limiting embodiments of the present disclosure described herein provide a three-phrase induction machine included in an elevator system is provided and is capable of avoiding CM noise concerns by realizes in a tradition an elevator system that implements a three-phrase induction machine. The three-phrase induction machine includes one or more armatures and a plurality of stators. The armatures are disposed in a hoistway and configured to electrically conduct electromagnetic energy, and the plurality of stators fixed to an elevator car configured to travel through the hoistway. Each of the stators are configured to conduct electrical current therethrough and to generate an electromagnetic field in response to the current. The electromagnetic field induces eddy currents that flow through the at least armature to generate a magnetic force to move the elevator car through the hoistway.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. The terms “about” and “substantially” are intended to include the degree of error associated with measurement of the particular quantity and/or manufacturing tolerances based upon the equipment available at the time of filing the application. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof.
Those of skill in the art will appreciate that various example embodiments are shown and described herein, each having certain features in the particular embodiments, but the present disclosure is not thus limited. Rather, the present disclosure can be modified to incorporate any number of variations, alterations, substitutions, combinations, sub-combinations, or equivalent arrangements not heretofore described, but which are commensurate with the scope of the present disclosure. Additionally, while various embodiments of the present disclosure have been described, it is to be understood that aspects of the present disclosure may include only some of the described embodiments. Accordingly, the present disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
