The present disclosure relates to electromagnetic devices, such as electrical transformers and inductors, and more particularly to an electromagnetic device, such as a transformer or similar device including magnetic core signal modulation.
Electromagnetic devices, such as inductors, transformers and similar devices include magnetic cores in which a magnetic flux flow may be generated in response to an electrical current flowing through a conductor winding associated with the magnetic core. As current (AC) in the magnetic core increases, the inductance in the core increases (energy storage in the device increases). In a transformer configuration which includes a primary winding connected to an electrical power source and a secondary winding connected to a load, changes in the current or voltage supplied by the electrical power source can significantly change the energy being stored in the magnetic core for transfer into the secondary.
In accordance with an embodiment, an electromagnetic device may include a core in which a magnetic flux is generable and an opening through the core. A primary conductor winding may be received in the opening and extend through the core. A primary electrical current signal flowing through the primary conductor winding generates a magnetic field about the primary conductor winding and a first magnetic flux flow in the core. A secondary conductor winding may be received in the opening and extend through the core. A first modular conductor winding may extend through the opening and encircle a first outer core portion of the core. A first modulation signal flowing through the first modular conductor winding modulates the primary electrical current signal to provide a modulated output current signal at an output of the secondary conductor winding.
In accordance with another embodiment, an electromagnetic device may include a core in which a magnetic flux is generable. The electromagnetic device may also include a first elongated opening through the core and a second elongated opening through the core. The electromagnetic device may also include a primary conductor winding extending in one direction through the core through the first elongated opening, and the primary conductor winding extending in an opposite direction through the core through the second elongated opening. A primary electrical current signal flowing through the primary conductor winding generates a magnetic field about the primary conductor winding. The magnetic field generates a first primary magnetic flux flow in one direction around the first elongated opening and a second primary magnetic flux flow in an opposite direction around the second elongated opening. The electromagnetic device may also include a secondary conductor winding extending in one direction through the core through the first elongated opening and the secondary conductor winding also extends in an opposite direction through the core through the second elongated opening. The electromagnetic device may additionally include a first modular conductor winding through the first elongated opening and encircling a first outer core portion of the core adjacent the first elongated opening. A first modulation signal flowing through the first modular conductor winding modulates the primary electrical current signal to provide a modulated output current signal at an output of the secondary conductor winding.
In accordance with further embodiment, a method for modulating a current in an electromagnetic device may include providing a core in which a magnetic flux is generable. The method may also include providing an opening through the core and extending a primary conductor winding through the opening and the core. Passing a primary electrical current signal through the primary conductor winding generates a magnetic field about the primary conductor winding and generates a first magnetic flux flow in the core. The method may additionally include extending a secondary conductor winding through the opening and the core and extending a modular conductor winding through the opening and encircling an outer core portion. The method may further include adjusting a modulation signal flowing through the modular conductor winding to modulate the primary electrical current signal to provide a modulated output current signal at the secondary conductor winding.
The following detailed description of embodiments refers to the accompanying drawings, which illustrate specific embodiments of the disclosure. Other embodiments having different structures and operations do not depart from the scope of the present disclosure.
The following detailed description of embodiments refers to the accompanying drawings, which illustrate specific embodiments of the disclosure. Other embodiments having different structures and operations do not depart from the scope of the present disclosure. Like reference numerals may refer to the same element or component in the different drawings.
In accordance with an embodiment of the present disclosure, a linear inductor is an electromagnetic device having only one electrical conductor wire winding or windings passing through a magnetic core. In accordance with another embodiment, a linear transformer is an electromagnetic device where a linear primary electrical conductor wire winding or windings and one or more linear secondary electrical conductor wire winding or windings pass through a magnetic core. The core may be one piece and no turns of the primary and secondary electrical conductors about the core are required. While the core may be one piece, the one piece core may be formed from a plurality of stacked plates or laminates. A current may be conducted through the primary. A magnetic flux from the current in the primary is absorbed by the core. When the current in the primary decreases the core transmits an electromotive force (desorbs) into the secondary wires. A feature of the linear transformer is the linear pass of the primary and secondary conductors through the core. One core may be used as a standalone device or a series of two or more cores may be used where a longer linear exposure is required. Another feature of this transformer is that the entire magnetic field or at least a substantial portion of the magnetic field generated by the current in the primary is absorbed by the core, and desorbed into the secondary. The core of the transformer may be sized or include dimensions so that substantially the entire magnetic field generated by the current is absorbed by the core and so that the magnetic flux is substantially completely contained with the core. This forms a highly efficient transformer with very low copper losses, high efficiency energy transfer, low thermal emission and very low radiated emissions. Additionally the linear transformer is a minimum of about 50% lower in volume and weight then existing configurations. Linear electromagnetic devices, such as linear transformers, inductors and similar devices are described in more detail in U.S. patent application Ser. No. 13/553,267, filed Jul. 19, 2012, entitled “Linear Electromagnetic Device” which is incorporated herein in its entirety by reference. A magnetic core flux sensor assembly is described in more detail in U.S. patent application Ser. No. 13/773,135, filed Feb. 21, 2013, entitled “Magnetic Core Flux Sensor and is incorporated herein in its entirety by reference.
An opening is formed through each of the plates 206 and the openings are aligned to form an opening 208 or passage through the core 204 when the plates 206 are stacked on one another with the plate openings 206 in alignment with one another. The opening 208 or passage may be formed in substantially a center or central portion of the core 204 and extend substantially perpendicular to a plane defined by each plate 206 of the stack of plates 206 or laminates. In another embodiment, the opening 208 may be formed off center from a central portion of the core 204 in the planes defined by each of the plates 206 for purposes of providing a particular magnetic flux or to satisfy certain constraints.
An electrical conductor 210 or wire may be received in the opening 208 and may extend through the core 204 perpendicular the plane of each of the plates 206. The electrical conductor 210 may be a primary conductor. In the exemplary embodiment illustrated in
Referring also to
As previously discussed, the electrical conductor 210 may be a plurality of primary conductors 212 that are aligned adjacent one another or disposed in a single row 216 within the elongated slot 214. Each of the conductors 212 may include a substantially square or rectangular cross-section as illustrated in
The cross-section of each primary conductor 212 may have a predetermined width “W” in a direction corresponding to an elongated dimension or length “L” of the elongated slot 214. An end primary conductor 218 at each end of the single row 216 of conductors is less than about one half of the predetermined width “W” from an end 220 of the elongated slot 214. Each conductor 212 also has a predetermined height “H.” Each conductor 212 is less than about one half of the predetermined height “H” from a side wall 222 of the elongated slot 214.
Similar to that previously described, each of the primary conductors 310 may have a substantially square or rectangular cross-section. An electrical current flowing through the primary conductor or conductors generates a magnetic field about the primary conductor. The core 304 may be sized or to include length and width dimensions of the plates 306 to absorb substantially the entire magnetic field to generate the magnetic flux as illustrated by broken lines 312 and 314 in
Each of the secondary conductors 302 extending through the core 304 may also have a substantially square or rectangular cross-section to receive an electro-motive force transmitted by the core 304.
The opening 308 through the core 304 may be an elongated slot 316 similar to the elongated slot 214 in
A cross-section of each primary conductor 310 of the plurality of conductors and each secondary conductor 302 of the plurality of conductors may have a predetermined width “W” in a direction corresponding to a length of the elongated slot 316 similar to that illustrated in
The cross-section of each primary conductor 310 and secondary conductor 302 may have a predetermined height “H.” Each primary conductor 310 and second conductor 302 is less than about one half of the predetermined height “H” from a side wall of the elongated slot 316.
Each of the plates 404 may include a first elongated opening 406 or slot and a second elongated opening 408 or slot. The first elongated opening 406 and the second elongated opening 408 may be parallel to one other or may be at some angle with respect to each other. The first elongated opening 406 and the second elongated opening 408 in each of the plates 404 are aligned with one another when the plates 404 are stacked on one another to form the core 402. Accordingly, the first elongated opening 406 and the second elongated opening 408 will be provided or formed through the core 402 when the plates 404 are stacked on one another to form the core 402.
Referring also to
In a transformer configuration, the electromagnetic device 400 may include a primary conductor winding 410 and a secondary conductor winding 412. Only a single conductor or wire wrap is illustrated in
An electrical current flowing through the primary conductor winding 410 generates a magnetic field around the primary conductor winding 410 and a magnetic flux flow is created in the magnetic core 402 as illustrated by arrows 412 and 414 in
The electromagnetic device 400 may also include at least one modular conductor winding or a first modular conductor winding 418 through the first elongated opening 406 and encircling a first outer core portion 420 of the core 402 adjacent the first core opening 406 as best shown in
Alternatively, the first modulation signal 422 being conducted through the first modular winding 418 in the opposite direction may produce a second magnetic flux flow in an opposite direction to arrow 432 in
The modulation signal 422 or signals in the modular winding 418 or windings may be adjusted as described herein to modulate the input signal and power passing from the primary conductor winding 410 to the secondary conductor winding 412. Accordingly, the first modulation signal 422 flowing through the first modular conductor winding 418 may be adjusted or controlled to generate the second magnetic flux flow 432 in the core 402. The second magnetic flux flow 432 may include a predetermined magnitude and direction of flow in the core 402 in response to adjusting the first modulation signal 422. As previously discussed, the first modulation signal 422 flowing in the first modular conductor winding 418 is adjustable for generating the second magnetic flux flow 432 in the core 402 to either increase the first primary magnetic flux flow 416 or attenuate the first primary magnetic flux flow 416 around the first elongated opening 406. The first modulation signal generator 430 may be configured to adjust the first modulation signal 422.
The electromagnetic device 400 may include a second modular conductor winding 434 through the second elongated opening 408 and encircling a second outer core portion 436 of the core 402 adjacent the second elongated opening 408. Only a single conductor or wire wrap is illustrated in
The first modulation signal 422 and the second modulation signal 440, when either one or both modulation signals are flowing through their respective modular conductor windings 418 and 434 may be adjusted or controlled (amplitude and direction of current flow in the modular windings) with respect to one another to provide the modulated output current signal 426 at the output of the secondary conductor winding 428.
Referring also to
A primary conductor winding 608 is received in the opening 606 and extends through the core 602 and is wound around a main portion 609 of the core 602. A primary electrical current signal 610 flowing through the primary conductor winding 608 generates a magnetic field about the primary conductor winding 608 and a first magnetic flux flow in the core 602. The first magnetic flux flow may be similar to either the magnetic flux flow 414 or 416 described with reference to
A secondary conductor winding 614 may be received in the opening 606 and may be wound around the main portion 609 of the core 602. The secondary conductor winding 614 may be coupled to an output 616 or load.
A modular conductor winding 618 may extend through the opening 606 and encircles an outer core portion 620 of the core 602. The outer portion 620 of the core 602 may be smaller than the main portion 609. For example, the outer core portion 620 may have a length “L/2” about half the length “L” of the main portion 609. A modulation signal 622 flowing through the first modular conductor winding 618 modulates the primary electrical current signal 610 to provide a modulated output current signal 624 at the output 616 of the secondary conductor winding. The first modulation signal 622 may be generated by a modulation signal generator 626.
The modulation signal generator 626 may be configured to adjust an amplitude and direction of flow of the current of the modulation signal 622 in the modular conductor winding 618. Accordingly, the modulation signal 622 may be adjusted to generate a second magnetic flux flow in the core 602. The second magnetic flux flow may include a predetermined magnitude and direction of flow in the core 602 in response to adjusting the modulation signal 622. The modulation signal 622 may be adjusted for generating the second magnetic flux flow in the core 602 to either increase the first magnetic flux flow or attenuate the first magnetic flux flow similar to that previously described herein.
In block 704, a primary conductor winding may extend through the opening and the core. The primary conductor winding may include a plurality conductors wound through the opening and may be disposed adjacent one another within the elongated opening in a single row. In block 706, a secondary conductor winding may extend through the opening and the core. The secondary conductor winding may include a plurality of conductors wound through the opening and disposed adjacent each other within the elongated slot and a single row. The primary conductor winding and the secondary conductor winding may be wound around a main portion of the core.
In block 708, a modular conductor winding may extend through the opening and encircle and outer portion of the core.
In block 710, an electrical source may be connected to the primary conductor winding and a load or output may be connected to the secondary conductor winding. In block 712, a primary electrical current signal may be passed through the primary conductor winding to generate a magnetic field around the primary conductor winding. The magnetic field generates a magnetic flux flow in the core. The core may be configured such that substantially the entire magnetic field may be absorbed by the core to generate magnetic flux in the core.
In block 714, a modulation signal may be passed through a modular conductor winding. The modulation signal may be adjusted to modulate the primary electrical current signal to provide a modulated output signal at the secondary conductor winding. The modulation signal generates a second magnetic flux flow in the core. The second magnetic flux flow may include a predetermined magnitude and direction of flow in the core in response to the modulation signal. The modulation signal may be adjusted to generate the predetermined magnitude and direction of flow of the second magnetic flux flow in the core. The modulation signal may be adjusted to cause the second magnetic flux flow in the core to either flow in the same direction as the first magnetic flux flow and contribute to the first magnetic flux flow by an amount corresponding to a magnitude of the second magnetic flux flow, or the second magnetic flux flow may flow in an opposite direction to the first magnetic flux flow and attenuate the first magnetic flux flow by an amount corresponding to a magnitude of the second magnetic flux flow. The modulation signal may be adjusted to cause the second magnetic flux flow to either saturate or attenuate the core.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. 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, elements, components, and/or groups thereof.
Although specific embodiments have been illustrated and described herein, those of ordinary skill in the art appreciate that any arrangement which is calculated to achieve the same purpose may be substituted for the specific embodiments shown and that the embodiments herein have other applications in other environments. This application is intended to cover any adaptations or variations of the present disclosure. The following claims are in no way intended to limit the scope of the disclosure to the specific embodiments described herein.
This application is a divisional of U.S. patent application Ser. No. 14/218,470, filed Mar. 18, 2014, now U.S. Pat. No. 9,947,450, which is a continuation-in-part of U.S. patent application Ser. No. 13/553,267, filed Jul. 19, 2012, entitled “Linear Transformer,” now U.S. Pat. No. 9,159,487 which is assigned to the same assignee as the present application and is incorporated herein in its entirety by reference.
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