Synchronous electric machine with reconfigurable rotor and stator poles

Abstract

The invention relates to a synchronous electric machine with reconfigurable rotor and stator poles. The invention discloses a non-magnetic motor. The electric machine may comprise: a stator comprising a first stator winding arrangement and a second stator winding arrangement; and a rotor comprising a first rotor winding arrangement and a second rotor winding arrangement. The electric machine may include a power transfer circuit configured to control the polarity and / or phase sequence of an excitation current used in exciting the first and second stator and rotor windings, and the stator and rotor poles thus generated, respectively.

Description

Technical Field

[0001] The present disclosure relates to electric machines, such as, but not necessarily limited to, electric machines operable to convert electrical power into mechanical power for the purpose of propelling a vehicle. Background Art

[0002] The electric motor may include a stator and a rotor, wherein the rotor is operable to rotate relative to the stator to perform work, such as for the purpose of generating mechanical power. When configured to convert electrical power into mechanical power for the purpose of propelling a vehicle, such an electric motor may be referred to as an electric vehicle motor. In the past, electric motors have included rare earth magnets or permanent magnets in an attempt to meet desired or competitive torque, power, and / or efficiency levels. The types of magnets employed in such electric motors may be relatively expensive, scarce, complex to manufacture, and / or prone to disadvantages that have historically been accepted due to the beneficial torque, power, and / or efficiency. Summary of the invention

[0003] One non-limiting aspect of the present disclosure relates to a magnet-free electric machine operable to provide a desired or competitive torque, power, and / or efficiency level without relying on the use of rare earth magnets, permanent magnets, or other magnets to generate a persistent magnetic field. The magnet-free electric machine may include rotor windings and stator windings and a power transmission circuit configured to actively control the electrical excitation of the windings based on operating conditions and / or other metrics so as to reconfigure the resulting rotor and stator poles accordingly in a manner intended to achieve a target torque, power, and / or efficiency level.

[0004] A non-limiting aspect of the present disclosure relates to a magnetless synchronous electric motor having reconfigurable rotor poles and stator poles. The motor may include a stator including a plurality of stator windings wound around a plurality of circumferentially spaced stator protrusions. A first stator winding set of the stator windings may be wound relative to a first stator protrusion set of the circumferentially spaced stator protrusions, and a second stator winding set of the stator windings may be wound relative to a second stator protrusion set of the circumferentially spaced stator protrusions. The motor may include a rotor including a plurality of rotor windings wound around a plurality of circumferentially spaced rotor protrusions. A first rotor winding set of the rotor windings may be wound relative to a first rotor protrusion set of the circumferentially spaced rotor protrusions, and a second rotor winding set of the rotor windings may be wound relative to a second rotor protrusion set of the circumferentially spaced rotor protrusions. The electric machine may include a power transmission circuit configured to control the polarity and / or phase sequence of excitation currents used in exciting the first and second stator windings and the rotor winding and the stator and rotor poles generated thereby, respectively.

[0005] The power transmission circuit can be operable to provide a first number of stator poles by providing a polarity and phase sequence of an excitation current for a first stator winding setting having a first polarity and a first phase sequence, respectively, for a first stator winding setting and providing a polarity and phase sequence of an excitation current for a second stator winding setting having a first polarity and a second phase sequence, respectively, for a second stator winding setting.

[0006] The power transmission circuit can be operable to provide a second number of stator poles by providing a first stator winding setting with a polarity and phase sequence of an excitation current for the first stator winding setting having a first polarity and a third phase sequence, respectively, and providing a second stator winding setting with a polarity and phase sequence of an excitation current for the second stator winding setting having a second polarity and a fourth phase sequence, respectively, opposite to the first polarity.

[0007] The stator winding may comprise a first branch, a second branch, a third branch, a fourth branch, a fifth branch and a sixth branch, optionally wherein the first stator winding arrangement comprises the first branch, the fourth branch and the fifth branch and the second stator winding arrangement comprises the second branch, the third branch and the sixth branch.

[0008] The first phase sequence may include phase A, phase B, and phase C, optionally wherein the first branch receives phase A, the fourth branch receives phase B, and the fifth branch receives phase C. The second phase sequence may include phase A', phase B', and phase C', optionally wherein the second branch receives phase A', the third branch receives phase B', and the sixth branch receives phase C'. The third phase sequence may include phase A, phase B, and phase C, optionally wherein the first branch receives phase A, the fourth branch receives phase C, and the fifth branch receives phase B. The fourth phase sequence may include phase A', phase B', and phase C', optionally wherein the second branch receives phase A', the third branch receives phase C', and the sixth branch receives phase B'.

[0009] The first polarity may correspond to a positive polarity, and the second polarity may correspond to a negative polarity.

[0010] The power transfer circuit may be operable to provide a first number of rotor poles by providing a polarity of the field current of the first rotor winding arrangement with a first polarity for the first rotor winding arrangement and by providing a polarity of the field current of the second rotor winding arrangement with the first polarity for the second rotor winding arrangement.

[0011] The power transfer circuit may be operable to provide a second number of rotor poles by providing the first rotor winding arrangement with a polarity of the excitation current of the first rotor winding arrangement having a first polarity and by providing the second rotor winding arrangement with a polarity of the excitation current of the second rotor winding arrangement having a second polarity opposite to the first polarity.

[0012] The first and second rotor windings may each have a single-phase configuration, such that the first rotor winding is arranged to include no more than the first rotor branch, and the second rotor winding is arranged to include no more than the second rotor branch.

[0013] The first and second rotor windings may each have a three-phase configuration, optionally wherein the first rotor winding is arranged to include a first rotor branch, a second rotor branch and a third rotor branch, and the second rotor winding is arranged to include a fourth rotor branch, a fifth rotor branch and a sixth rotor branch.

[0014] The three-phase configuration may include first, second and third rotor branches connected in series and fourth, fifth and sixth rotor branches connected in series.

[0015] The first, second, third, fourth, fifth and sixth rotor branches may be formed with conductors, optionally wherein the second and third rotor branches are wound with fewer turns of conductor than the first rotor branch, and the fifth and sixth rotor branches are wound with fewer turns of conductor than the fourth rotor branch.

[0016] The three-phase configuration may include a first rotor branch connected in parallel with the second rotor branch and first and second rotor branches connected in series with the third rotor branch, and a fourth rotor branch connected in parallel with the fifth rotor branch and fourth and fifth rotor branches connected in series with the sixth rotor branch.

[0017] The first, second, third, fourth, fifth and sixth rotor branches may be formed with conductors, optionally wherein the conductors of the first and second branches have a smaller cross-sectional area than the conductors of the third rotor branch, and the conductors of the fourth and fifth rotor branches have a smaller cross-sectional area than the conductors of the sixth rotor branch.

[0018] One non-limiting aspect of the present disclosure relates to an electric machine with reconfigurable machine poles. The electric machine may include a stator having a plurality of stator windings arranged into a first stator branch, a second stator branch, a third stator branch, a fourth stator branch, a fifth stator branch, and a sixth stator branch, a rotor having a plurality of rotor windings arranged into a first rotor branch and a second rotor branch, and a power transmission circuit. The power transmission circuit may be configured to: provide a first number of machine poles by delivering an excitation current having a first polarity and a first phase sequence to the first, fourth, and fifth stator branches, delivering an excitation current having a first polarity and a second phase sequence to the second, third, and sixth stator branches, and delivering an excitation current having a first polarity to the first rotor branch and delivering an excitation current having a first polarity to the second rotor branch; and provide a second number of machine poles by delivering an excitation current having a first polarity and a third phase sequence to the first, fourth, and fifth branches, delivering an excitation current having a second polarity and a fourth phase sequence to the second, third, and sixth branches, delivering an excitation current having a first polarity to the first rotor branch, and delivering an excitation current having a second polarity to the second rotor branch.

[0019] The first and second rotor branches may each have a single-phase configuration.

[0020] The first and second rotor branches can each have a three-phase configuration, optionally wherein the three-phase configuration comprises a first rotor branch, a second rotor branch and a third rotor branch connected in series, wherein the first, second and third rotor branches are formed with conductors such that the first and second rotor branches are wound with fewer turns of conductor than the third rotor branch.

[0021] The first and second rotor branches may each have a three-phase configuration, optionally wherein the three-phase configuration comprises a first rotor branch, a second rotor branch and a third rotor branch, wherein the first rotor branch is connected in parallel with the second rotor branch and the first and second rotor branches are connected in series with the third rotor branch.

[0022] The first, second and third branches may be formed with conductors, optionally wherein the conductors of the first and second branches have a smaller cross-sectional area than the conductor of the third branch.

[0023] One non-limiting aspect of the present disclosure relates to a vehicle. The vehicle may include an electric motor configured to convert electrical power into mechanical power to propel the vehicle. The electric motor may include: a stator including a first stator winding arrangement and a second stator winding arrangement; a rotor including a first rotor winding arrangement and a second rotor winding arrangement; and a power transmission circuit configured to control the polarity and / or phase sequence of the excitation current used in exciting the first and second stator windings and the rotor winding and the stator magnetic poles and the rotor magnetic poles generated thereby, respectively.

[0024] The present invention provides the following technical solutions.

[0025] Technical Solution 1. A magnetless synchronous electric motor with reconfigurable rotor poles and stator poles, comprising:

[0026] a stator comprising a plurality of stator windings wound around a plurality of circumferentially spaced apart stator projections, wherein a first stator winding arrangement of the stator windings is wound relative to a first stator projection arrangement of the circumferentially spaced apart stator projections and a second stator winding arrangement of the stator windings is wound relative to a second stator projection arrangement of the circumferentially spaced apart stator projections;

[0027] a rotor comprising a plurality of rotor windings wound around a plurality of circumferentially spaced apart rotor protrusions, wherein a first rotor winding arrangement of the rotor windings is wound relative to a first rotor protrusion arrangement of the circumferentially spaced apart rotor protrusions and a second rotor winding arrangement of the rotor windings is wound relative to a second rotor protrusion arrangement of the circumferentially spaced apart rotor protrusions; and

[0028] A power transmission circuit is configured to control the polarity and / or phase sequence of the excitation current used in exciting the first and second stator windings and the rotor winding and the stator poles and rotor poles generated thereby, respectively.

[0029] Technical Solution 2. The magnetless synchronous electric motor according to Technical Solution 1, wherein:

[0030] The power transmission circuit is operable to provide a first number of stator poles by:

[0031] providing the first stator winding arrangement with a polarity and a phase sequence of an excitation current of the first stator winding arrangement having a first polarity and a first phase sequence, respectively; and

[0032] The second stator winding arrangement is provided with a polarity and a phase sequence of an excitation current of the second stator winding arrangement having the first polarity and the second phase sequence, respectively.

[0033] Technical Solution 3. A magnetless synchronous electric motor according to Technical Solution 2, wherein:

[0034] The power transmission circuit is operable to provide the second number of stator poles by:

[0035] providing the first stator winding arrangement with a polarity and a phase sequence of an excitation current of the first stator winding arrangement having the first polarity and a third phase sequence respectively; and

[0036] The second stator winding arrangement is provided with a polarity and a phase sequence of an excitation current of the second stator winding arrangement having a second polarity and a fourth phase sequence, respectively, which are opposite to the first polarity.

[0037] Technical Solution 4. The magnetless synchronous electric motor according to Technical Solution 3, wherein:

[0038] The stator winding includes a first branch, a second branch, a third branch, a fourth branch, a fifth branch and a sixth branch;

[0039] The first stator winding arrangement includes the first branch, the fourth branch and the fifth branch;

[0040] The second stator winding arrangement comprises the second branch, the third branch and the sixth branch.

[0041] Technical Solution 5. The magnetless synchronous electric motor according to Technical Solution 4, wherein:

[0042] The first phase sequence includes phase A, phase B and phase C, wherein the first branch receives the phase A, the fourth branch receives the phase B, and the fifth branch receives the phase C;

[0043] The second phase sequence includes an A' phase, a B' phase, and a C' phase, wherein the second branch receives the A' phase, the third branch receives the B' phase, and the sixth branch receives the C' phase;

[0044] The third phase sequence includes the A phase, the B phase, and the C phase, wherein the first branch receives the A phase, the fourth branch receives the C phase, and the fifth branch receives the B phase; and

[0045] The fourth phase sequence includes the A′ phase, the B′ phase, and the C′ phase, wherein the second branch receives the A′ phase, the third branch receives the C′ phase, and the sixth branch receives the B′ phase.

[0046] Technical Solution 6. The magnetless synchronous electric motor according to Technical Solution 5, wherein:

[0047] The first polarity corresponds to a positive polarity; and

[0048] The second polarity corresponds to negative polarity.

[0049] Technical Solution 7. The magnetless synchronous electric motor according to Technical Solution 1, wherein:

[0050] The power transfer circuit is operable to provide a first number of the rotor poles by:

[0051] providing the first rotor winding arrangement with a polarity of the field current of the first rotor winding arrangement having a first polarity; and

[0052] The polarity of the field current of the second rotor winding arrangement is provided to the second rotor winding arrangement with the first polarity.

[0053] Technical Solution 8. The magnetless synchronous electric motor according to Technical Solution 7, wherein:

[0054] The power transfer circuit is operable to provide a second number of the rotor poles by:

[0055] providing the first rotor winding arrangement with a polarity of the field current of the first rotor winding arrangement having the first polarity; and

[0056] The polarity of the field current of the second rotor winding arrangement is provided to the second rotor winding arrangement with a second polarity opposite to the first polarity.

[0057] Technical Solution 9. The magnetless synchronous electric motor according to Technical Solution 8, wherein:

[0058] The first and second rotor windings each have a single-phase configuration such that the first rotor winding is arranged to include no more than a first rotor branch and the second rotor winding is arranged to include no more than a second rotor branch.

[0059] Technical Solution 10. The magnetless synchronous electric motor according to Technical Solution 8, wherein:

[0060] The first and second rotor windings each have a three-phase configuration, wherein the first rotor winding is arranged to include a first rotor branch, a second rotor branch and a third rotor branch, and the second rotor winding is arranged to include a fourth rotor branch, a fifth rotor branch and a sixth rotor branch.

[0061] Technical Solution 11. The magnetless synchronous electric motor according to Technical Solution 10, wherein:

[0062] The three-phase configuration comprises the first, second and third rotor branches connected in series and the fourth, fifth and sixth rotor branches connected in series.

[0063] Technical Solution 12. The magnetless synchronous electric motor according to Technical Solution 11, wherein:

[0064] The first, second, third, fourth, fifth and sixth rotor branches are formed with conductors, wherein the second and third rotor branches are wound with fewer turns of the conductor than the first rotor branch, and the fifth and sixth rotor branches are wound with fewer turns of the conductor than the fourth rotor branch.

[0065] Technical Solution 13. The magnetless synchronous electric motor according to Technical Solution 10, wherein:

[0066] The three-phase configuration includes the first rotor branch connected in parallel with the second rotor branch, the first and second rotor branches connected in series with the third rotor branch, and the fourth rotor branch connected in parallel with the fifth rotor branch, and the fourth and fifth rotor branches connected in series with the sixth rotor branch.

[0067] Technical Solution 14. The magnetless synchronous electric motor according to Technical Solution 13, wherein:

[0068] The first, second, third, fourth, fifth and sixth rotor branches are formed with conductors, wherein the conductors of the first and second branches have a smaller cross-sectional area than the conductors of the third rotor branch, and the conductors of the fourth and fifth rotor branches have a smaller cross-sectional area than the conductors of the sixth rotor branch.

[0069] Technical Solution 15. A motor with reconfigurable machine poles, comprising:

[0070] a stator having a plurality of stator windings arranged into a first stator branch, a second stator branch, a third stator branch, a fourth stator branch, a fifth stator branch, and a sixth stator branch;

[0071] a rotor having a plurality of rotor windings arranged into a first rotor branch and a second rotor branch;

[0072] A power delivery circuit configured to:

[0073] providing a first number of machine poles by delivering a field current having a first polarity and a first phase sequence to the first, fourth and fifth stator branches, delivering a field current having the first polarity and a second phase sequence to the second, third and sixth stator branches, and delivering a field current having the first polarity to the first rotor branch and delivering a field current having the first polarity to the second rotor branch;

[0074] A second number of machine poles is provided by delivering an excitation current having the first polarity and a third phase sequence to the first, fourth and fifth branches, delivering an excitation current having a second polarity and a fourth phase sequence to the second, third and sixth branches, delivering an excitation current having the first polarity to the first rotor branch and delivering an excitation current having the second polarity to the second rotor branch.

[0075] Technical Solution 16. The motor according to Technical Solution 15, wherein:

[0076] The first and second rotor branches each have a single-phase configuration.

[0077] Technical Solution 17. The motor according to Technical Solution 15, wherein:

[0078] The first and second rotor branches each have a three-phase configuration, wherein the three-phase configuration includes a first rotor branch, a second rotor branch and a third rotor branch connected in series, wherein the first, second and third rotor branches are formed with conductors so that the first and second rotor branches are wound with fewer turns of the conductor than the third rotor branch.

[0079] Technical Solution 18. The motor according to Technical Solution 17, wherein:

[0080] The first and second rotor branches each have a three-phase configuration, wherein the three-phase configuration includes a first rotor branch, a second rotor branch and a third rotor branch, wherein the first rotor branch is connected in parallel with the second rotor branch, and the first and second rotor branches are connected in series with the third rotor branch.

[0081] Technical Solution 19. The motor according to Technical Solution 18, wherein:

[0082] The first, second and third branches are formed with conductors, wherein the conductors of the first and second branches have a smaller cross-sectional area than the conductor of the third branch.

[0083] Technical Solution 20. A means of transport, comprising:

[0084] an electric motor configured to convert electrical power into mechanical power for the purpose of propelling the vehicle; and

[0085] Wherein, the electric motor comprises:

[0086] a stator comprising a first stator winding arrangement and a second stator winding arrangement;

[0087] a rotor comprising a first rotor winding arrangement and a second rotor winding arrangement; and

[0088] A power transmission circuit is configured to control the polarity and / or phase sequence of the excitation current used in exciting the first and second stator windings and the rotor winding and the stator poles and rotor poles generated thereby, respectively.

[0089] These features and advantages and other features and advantages of the present teachings may be apparent from the following detailed description of the modes for carrying out the present teachings when combined with the accompanying drawings. It should be understood that even though the following drawings and embodiments may be described separately, their individual features may also be combined into additional embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0090] The accompanying drawings, which may be incorporated in and constitute a part of this specification, illustrate implementations of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0091] Figure 1 A schematic diagram of an electric machine according to one non-limiting aspect of the present disclosure is illustrated.

[0092] Figure 2 A schematic diagram of a vehicle having an electric vehicle motor according to one non-limiting aspect of the present disclosure is illustrated.

[0093] Figure 3 A partial schematic circuit diagram of an electric machine according to one non-limiting aspect of the present disclosure is illustrated.

[0094] Figure 4 A schematic diagram of an 8-pole configuration of an electric machine according to one non-limiting aspect of the present disclosure is illustrated.

[0095] Figure 5 A schematic diagram of a 4-pole configuration of an electric machine according to one non-limiting aspect of the present disclosure is illustrated.

[0096] Figure 6 A schematic diagram of an 8-pole configuration of an electric machine according to one non-limiting aspect of the present disclosure is illustrated.

[0097] Figure 7 A schematic diagram of a 4-pole configuration of an electric machine according to one non-limiting aspect of the present disclosure is illustrated.

[0098] Figure 8 A partial schematic circuit diagram of an electric machine having a three-phase rotor configuration according to one non-limiting aspect of the present disclosure is illustrated.

[0099] Fig. 9 A partial schematic circuit diagram of an electric machine having a series three-phase rotor configuration according to one non-limiting aspect of the present disclosure is illustrated. DETAILED DESCRIPTION

[0100] As desired, detailed embodiments of the present disclosure may be disclosed herein; however, it is understood that the disclosed embodiments may be merely examples of disclosures that may be implemented in various and alternative forms. The drawings may not necessarily be drawn to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, the specific structural and functional details disclosed herein may not be interpreted as limiting, but merely as a representative basis for teaching those skilled in the art to use the present disclosure in various ways.

[0101] Figure 1 A schematic diagram of an electric machine 10 according to one non-limiting aspect of the present disclosure is illustrated. The electric machine 10 may be of a type that employs a rotor 12 to apply mechanical force to a load in proportion to the electrical excitation of the rotor 12 and / or to generate electrical energy in response to the rotation of the rotor 12. At least in the illustrated configuration, the electric machine 10 may be referred to as an electric vehicle motor 10 that is operable for propulsion of a vehicle and / or regenerative braking. Figure 2 A schematic diagram of a vehicle 14 having an electric vehicle motor 10 is illustrated in accordance with one non-limiting aspect of the present disclosure. The electric vehicle motor 10 may be employed within the vehicle 14 to facilitate applying mechanical power to a propulsion system, powertrain, or transmission system 16 operable to propel or otherwise drive the vehicle 14. The vehicle 14 is illustrated as a hybrid type, as the powertrain 12 optionally includes an internal combustion engine (ICE) 18 for generating mechanical power. The powertrain 16 may include a transmission, drive shafts, differentials, axles, and / or other components to facilitate applying rotational force from a rotor shaft 30 (see FIG. 1 ) coupled to the rotor 12. Figure 1 ) are transmitted to wheels 20, 22, 24, 26. Vehicle 14 is shown including powertrain 12 operable with front wheels 20, 24 for exemplary purposes. Although illustrated as an electric vehicle motor 10, the present disclosure fully contemplates that electric machine 10 may be operable for other purposes, applications, and in other environments where converting electrical power to mechanical power may be beneficial.

[0102] refer to Figure 1, the electric machine 10 may include a housing 32 configured to support a rear end (not shown) of the rotor shaft 30 while allowing the rotor 10 to rotate relative to the stator 36 within the air gap 34. The stator 36 may be disposed annularly around the rotor 12 for the purpose of generating a rotating magnetic field (RMF), which, as will be appreciated by those skilled in the art, may be used to impart a rotational torque sufficient to rotate the rotor 12. Although not shown in detail, the stator 36 may include stator windings 38 wound around a plurality of circumferentially spaced stator protrusions 40, which, when excited, may be capable of affecting the RMF and the resulting rotation of the rotor 12. The rotor 12 may include a plurality of rotor windings 44 wound around a plurality of circumferentially spaced rotor protrusions 46, which, when excited, may be used to induce a rotor magnetic field. The rotor magnetic field may interact with the RMF to facilitate rotating the rotor shaft 30 to propel the vehicle 14 and / or regenerative braking in response to the rotation of the rotor shaft. The rotor 12 may be formed in a generally annular shape, optionally from a plurality of laminations stacked axially in side-by-side facing relationship along the axis of rotation A. Although Figure 1 As generally shown in FIG. 1 and described in more detail below, the present disclosure contemplates stator windings 38 and rotor windings 44 having a variety of configurations.

[0103] Figure 3 A partial schematic circuit diagram of an electric machine 10 according to one non-limiting aspect of the present disclosure is illustrated. The electric machine 10 may include a power transmission circuit 50 configured to electrically excite the rotor winding and the stator winding. The power transmission circuit 50 may be operable to exchange electrical power with a power source 52 (optionally with capacitors for capacitive smoothing filtering, etc.). The power source 52 may be a rechargeable energy storage system (RESS) or other features suitable for providing direct current (DC) electrical power to and / or receiving electrical power from a rotor circuit portion 54 and / or a stator circuit portion 56 associated with the rotor 12 and the stator 36, respectively. The rotor circuit portion 54 may include a switch 60 and a rotor interface 62, which cooperate to facilitate providing a DC excitation current to the rotor winding 44 (optionally with the aid of a diode 64, a capacitor 66, and a DC-DC converter). The rotor interface 62 may correspond to the transformer or inductive arrangement shown, whereby the DC excitation current may be provided to the rotor winding 44 in a contactless manner. This is shown for exemplary purposes, as the present disclosure fully contemplates contact-based rotor interface configurations, such as, but not necessarily limited to, the use of brushes and slip rings. The stator circuit portion 56 may include a stator interface 70 to facilitate providing an alternating current (AC) field current to the stator windings (such as in the form of a multi-phase or three-phase AC field current). The stator interface 70 may correspond to the illustrated first converter 72 and second inverter 74, however, the present disclosure fully contemplates other rotor interface configurations.

[0104] The stator winding 38 may be configured to include a plurality of stator winding arrangements 76, 78, optionally wherein each arrangement is wound around a corresponding plurality of stator projections 40. Figure 4 As shown in the schematic diagram of , for example, a first stator winding arrangement 76 can be wound relative to a first stator projection arrangement (not separately labeled) of the stator projections, and a second stator winding arrangement 78 can be wound relative to a second stator projection arrangement (not separately labeled) of the stator projections. The first stator winding arrangement 76 and the second stator winding arrangement 78 can be provided in a three-phase configuration with a first stator branch 80, a second stator branch 82, a third stator branch 84, a fourth stator branch 86, a fifth stator branch 88, and a sixth stator branch 90, optionally in a manner illustrated, wherein the first stator winding arrangement 76 includes the first stator branch 80, the fourth stator branch 86, and the fifth stator branch 88, and the second stator winding arrangement 78 includes the second stator branch 82, the third stator branch 84, and the sixth stator branch 90. The rotor winding 44 can be configured to include a plurality of rotor winding arrangements 96, 98, optionally wherein each arrangement is wound around a corresponding plurality of rotor projections 46. For example, a first rotor winding arrangement 96 may be wound relative to a first rotor protrusion arrangement (not separately labeled) of the rotor protrusion 46, and a second rotor winding arrangement 98 may be wound relative to a second rotor protrusion (not separately labeled) of the rotor protrusion 46. The first rotor winding arrangement 96 and the second rotor winding arrangement 98 may be provided in a single-phase configuration having a first rotor branch 100 and a second rotor branch 102, optionally in the illustrated manner, wherein the first rotor winding arrangement 96 includes the first rotor branch 100 and the second rotor winding arrangement 98 includes the second rotor branch 102.

[0105] refer to Figure 3, the power transmission circuit 50 may be operable to selectively control the polarity and / or phase sequence of the excitation current provided to the first and second stator windings 76 and the rotor winding 78, respectively (i.e., DC excitation of the rotor winding 44 and AC excitation of the stator winding 38). The power transmission circuit 50 may include a controller 104 having a computer-readable storage medium having a plurality of non-transitory instructions stored thereon, which, when executed by one or more processors, may be operable to facilitate processes, controls, and / or other activities incidental to facilitating the operations contemplated herein. The power transmission circuit 50 may be configured in this manner to selectively change the polarity and / or phase sequence of the excitation current so as to control the motor 10 to provide a desired or competitive torque, power, and / or efficiency level, optionally without relying on the use of rare earth magnets, permanent magnets, or other magnets to generate a continuous magnetic field, i.e., to provide a magnet-free motor 10. Such a magnet-free motor 10 may be operable to actively control the excitation current and the stator and rotor poles generated thereby, respectively. For example, field currents may be selected based on operating conditions and / or other metrics to accordingly reconfigure the resulting rotor and stator poles in a manner intended to achieve target torque, power, and / or efficiency levels.

[0106] One non-limiting aspect of the present disclosure contemplates reconfiguring the rotor poles and stator poles so that the electric machine 10 can have a first number of resulting machine poles in some cases and a second number of machine poles in other cases without mechanically changing the stator windings and / or the rotor windings or making other physical changes to the electric machine 10 other than adjusting the polarity, phase sequence, or other characteristics of the excitation current used to excite the stator windings 38 or the rotor windings 44 accordingly. This ability to electronically or electrically reconfigure the rotor poles and / or the stator poles, and thus the resulting machine poles, can be beneficial in providing a variable pole machine (VPM) having capabilities equivalent to permanent magnet type electric machines but without relying on permanent magnets to achieve target torque, power, and / or efficiency levels. It will be appreciated by those skilled in the art that the rotor poles and / or the stator poles combine to define machine poles or what may generally be referred to as a plurality of poles of the electric machine 10. In other words, the motor 10 can individually and selectively energize the stator windings and / or the rotor windings 76, 78, or more specifically the stator winding arrangements 76, 78 and / or the rotor winding arrangements 96, 98, to achieve a desired number of rotor poles and stator poles, for example, a first or second number of rotor poles and stator poles. For example, the first and second numbers of rotor poles and stator poles can correspond to providing a P number of machine poles (such as four poles) and a 2P number of machine poles (e.g., eight poles). Similarly, more or fewer machine poles can be generated, for example to facilitate switching between a 6-pole configuration and a 12-pole configuration, an 8-pole configuration and a 16-pole configuration, etc., optionally with other incremental (e.g., 3P, 4P, etc.) numbers of machine poles.

[0107] Figure 4 A schematic diagram of an 8-pole configuration of an electric machine 10 according to one non-limiting aspect of the present disclosure is illustrated. The 8-pole configuration may correspond to a first number of stator poles interacting with a first number of rotor poles, with the resulting poles and their directions indicated by arrows. Figure 5 FIG. 1 illustrates a non-limiting aspect of the present disclosure. Figure 4 Schematic diagram of a 4-pole configuration of the motor 10. The 4-pole configuration may correspond to a second number of stator poles interacting with a second number of rotor poles, with the resulting poles and their directions indicated by arrows. The table shown below may be used to indicate the polarity and phase sequence used to energize each of the stator winding arrangements 76, 78 and the rotor winding arrangements 96, 98 to switch between the 8-pole configuration and the 4-pole configuration.

[0108]

[0109] The 8-pole configuration may correspond to providing a polarity and phase sequence of excitation current for a first stator winding arrangement 76 having a first stator polarity and a first stator phase sequence, a second stator winding arrangement 78 having a first stator polarity and a second stator phase sequence, a first rotor winding arrangement 96 having a first rotor polarity and a first rotor phase sequence, and a second rotor winding arrangement 98 having a first rotor polarity and a second rotor phase sequence. The stator pole polarity and the rotor pole polarity may be defined relative to the positive polarity of the power source 52, i.e., the first polarity corresponds to the positive polarity and the second polarity corresponds to the second polarity. The first stator phase sequence may include an A phase, a B phase, and a C phase, wherein the first stator branch 80 receives the A phase, the fourth stator branch 86 receives the B phase, and the fifth stator branch 88 receives the C phase. The second stator phase sequence may include an A' phase, a B' phase, and a C' phase, wherein the second stator branch 82 receives the A' phase, the third stator branch 84 receives the B' phase, and the sixth stator branch 90 receives the C' phase. Phase A, Phase B, Phase C, Phase A', Phase B' and Phase C' may correspond to three-phase AC current output from the first inverter 72 and the second inverter 74, respectively, optionally wherein the A', B' and C' phases are time-shifted, delayed or otherwise differently ordered relative to the corresponding A, B and C' phases. The first rotor phase sequence may include an I phase, wherein the first rotor branch 100 receives the I phase, and the second rotor phase sequence may include an I' phase, wherein the second rotor branch 102 receives the I' phase. The I phase and the I' phase may correspond to DC current output from the DC-DC converter to the first rotor winding arrangement and the second rotor winding arrangement, respectively, optionally wherein the I' phase is time-shifted, delayed or otherwise differently ordered relative to the corresponding I phase.

[0110] Figure 6 A schematic diagram of an 8-pole configuration of an electric machine 10 according to one non-limiting aspect of the present disclosure is illustrated. The concentrated configuration may correspond to a first rotor winding arrangement 96 including a first rotor branch 100 and a second rotor winding arrangement 98 including a second rotor branch 102, the first rotor branch 100 and the second rotor branch 102 being wound at a ratio of Figure 4 In the configuration, more rotor protrusions 46 are arranged around, for example, with 16 salient poles instead of 8 salient poles. The 8-pole configuration may correspond to a first number of stator poles interacting with a first number of rotor poles, with the resulting poles and their directions indicated by arrows, such that 8 poles are produced by combining two adjacent poles having the same directionality to form one pole. Figure 7 FIG. 1 illustrates a non-limiting aspect of the present disclosure. Figure 6Schematic diagram of a 4-pole configuration of the motor 10. The 4-pole configuration may correspond to a second number of stator poles interacting with a second number of rotor poles, the resulting poles and their directions being indicated by arrows, such that the 4 poles are produced by combining four adjacent poles having the same directionality to form one pole. The excitation current of the concentrated configuration may correspond to the excitation current given in the above table, i.e., the same excitation current may be used in the concentrated configuration to excite the stator winding 38 and the rotor winding 44 between the 8-pole configuration and the 4-pole configuration.

[0111] Figure 8 A partial schematic circuit diagram of an electric machine 10 having a three-phase rotor configuration according to one non-limiting aspect of the present disclosure is illustrated. With respect to the operation of the rotor circuit portion 54 and the stator circuit portion 56, the electric machine 10 may be similar to the electric machines described above, with elements having common reference numerals functioning similarly, with one difference being that the first rotor winding arrangement 96 additionally includes a third rotor branch 108 and a fourth rotor branch 110, and the second rotor winding arrangement 98 additionally includes a fifth rotor branch 112 and a sixth rotor branch 114. In an exemplary use case where the electric machine 10 is configured for switching between four poles and eight poles, the table shown below may be used to represent the polarity and phase sequence for exciting each of the stator winding arrangements 76, 78 and the rotor winding arrangements 96, 98 to switch between an 8-pole configuration and a 4-pole configuration.

[0112]

[0113]

[0114] The switching between the 4-pole configuration and the 8-pole configuration may correspond to the above description of Figure 4 The polarity and phase sequence of the excitation current are provided for the first stator winding arrangement 76 and the second stator winding arrangement 78 in the manner described. As additional rotor branches 108, 110, 112, 114 are added to the first rotor winding arrangement 96 and the second rotor winding arrangement 98, switching between a 4-pole configuration and an 8-pole configuration may correspond to a change in the above description with respect to Figure 4The different ways described provide polarity and phase sequence of the excitation current for the first rotor winding arrangement 96 and the second rotor winding arrangement 98. Due to the directionality of some of the parallel and series connections and the differently wound rotor branches 108, 110, 112, 114, the polarity and phase sequence may include I-phase and I'-phase, wherein the rotor branches 108, 110, 112, 114 connected in parallel have half the excitation current and opposite polarity relative to the excitation current of the rotor branches 100, 102 connected in series therewith. Due to the lower current requirements, the conductors forming the third branch 108, the fourth branch 110, the fifth branch 112 and the sixth rotor branch 114 may have a smaller cross-sectional area relative to the conductors forming the first rotor branch 100 and the second rotor branch 102.

[0115] Fig. 9 A partial schematic circuit diagram of an electric machine 10 having a series three-phase rotor configuration according to one non-limiting aspect of the present disclosure is illustrated. With respect to the operation of the rotor circuit portion 54 and the stator circuit portion 56, the electric machine 10 may be similar to the electric machine described above, with elements having common reference numerals functioning similarly, with one difference being that the first rotor winding arrangement has a first rotor branch 100, a third rotor branch 108, and a fourth rotor branch 110 connected in series, and the second rotor winding arrangement 98 has a second rotor branch 102, a fifth rotor branch 112, and a sixth rotor branch 114 similarly connected in series. In an exemplary use case where the electric machine 10 is configured for switching between four poles and eight poles, the table shown below may be used to represent the polarity and phase sequence for exciting each of the stator winding arrangements 76, 78 and the rotor winding arrangements 96, 98 to switch between an 8-pole configuration and a 4-pole configuration.

[0116]

[0117] The switching between the 4-pole configuration and the 8-pole configuration may correspond to the above description of Figure 4 The described manner provides the polarity and phase sequence of the excitation current for the first stator winding arrangement 76, the second stator winding arrangement 78, the first rotor winding arrangement 96 and the second rotor winding arrangement 98. Figure 8 Different, and due to the directionality of some of the series-connected and differently wound rotor branches 108, 110, 112, 114, the polarity and phase sequence may include an I phase and an I' phase, where some rotor branches 108, 110, 112, 114 of the same set of rotor windings 96, 98 receive opposite polarities. Due to the series connection, the third rotor branch 108 and the fourth rotor branch 110 may be wound with fewer turns of conductor than the first rotor branch 100, and the fifth rotor branch 112 and the sixth rotor branch 114 may be wound with fewer turns of conductor than the second rotor branch 102.

[0118] As described above, the present disclosure relates to a magnetless synchronous motor that can provide similar or better wheel shaft torque, power and efficiency as a permanent magnet synchronous motor. The motor can actively change the number of stator poles by controlling the polarity and / or phase sequence of the stator inverter current, such as by controlling the polarity of the voltage applied to the rotor winding using a DC-DC converter or a double-pole double-throw (DPDT) switch. The change of the rotor poles between different operations can be a controller to maintain a balanced winding configuration related to the stator pole change, such as determining the change of the poles using the same position sensor based on the selection of the rotor poles. A high number of poles can be used to achieve excellent wheel shaft torque, and a low number of poles can be used to achieve low base frequency, high speed, power and efficiency. Increased air gaps and retaining sleeves can be used for high-speed capabilities, low torque ripple, low magnetic load, low core loss, low AC copper loss and / or reduced back iron saturation in low pole number mode. Under certain operating / load / fault conditions, active deactivation of (multiple) specific coils of two sets of windings can be used to improve overall drive system efficiency and fault tolerance. The coils from the various winding arrangements may optionally not share the same slots so that a fault in one winding does not propagate to another winding, thereby enabling the faulty machine to continue to operate on the remaining healthy winding. The power transmission circuit may be operable to select between a high-pole mode and a low-pole mode depending on the operating conditions, for example, 1 zero-efficiency-difference line, 2 a specific speed level, 3 an economic mode or a watts-to-freedom mode, etc., optionally with corresponding control of the currents of specific stator / rotor coils in different sequences, amplitudes, etc., to achieve smooth pole changes with minimal transients. Due to the overlapping air gap fields (e.g., by controlling the simultaneous presence of an eight-pole field and a four-pole field), reduced torque pulsation and improved torque density may be provided, including optionally eliminating or minimizing unbalanced radial forces due to the 180-degree symmetry of the windings, which may be achieved by ensuring that the overlapping flux is separated by more than two poles. In some embodiments, forced convection rotor cooling may be included and used for cooling channels on the rotor core or in-slot rotor cooling. When used with a vehicle, the vehicle may include the use of a multi-stage gearbox or planetary gearbox with appropriate gear ratios that can accommodate maximum speeds in low pole count mode, optionally using end rings for rotor end winding retention and rotor balancing at high speeds.

[0119] The terms "comprise", "include" and "have" are inclusive and therefore specify the presence of the features, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements or parts. The order of steps, processes and operations can be changed when possible, and additional or alternative steps can be adopted. As used in this specification, the term "or" includes any one and all combinations of the associated enumerated items. The term "any of..." is understood to include any possible combination of the cited items, including "any of" the cited items. "One", "one", "the", "at least one" and "one or more" are used interchangeably to indicate that at least one of the items exists. There may be multiple such items, unless the context clearly indicates otherwise. Unless otherwise clearly or clearly indicated by the context, including the attached claims, all parameter values ​​(e.g., the value of quantity or condition) should be understood to be modified by the term "about" in all cases, regardless of whether "about" actually appears before the value. A component "configured to" perform a specified function is able to perform the specified function without change, rather than just having the potential to perform the specified function after further modification. In other words, when expressly configured to perform a specified function, the described hardware is specifically selected, created, implemented, utilized, programmed and / or designed for the purpose of performing the specified function.

[0120] Although various embodiments have been described, the description is intended to be exemplary, not restrictive, and it is obvious to those of ordinary skill in the art that more embodiments and implementations within the scope of the embodiments are possible. Unless specifically limited, any feature of any embodiment can be used in combination with any other feature or element in any other embodiment or be replaced by any other feature or element in any other embodiment. Therefore, the embodiments are not limited except according to the attached claims and their equivalents. In addition, various modifications and changes can be made within the scope of the attached claims. Although several modes for performing many aspects of this teaching have been described in detail, people familiar with the fields involved in these teachings will recognize various alternative aspects for practicing this teaching within the scope of the attached claims. It is intended that all content contained in the above description or shown in the accompanying drawings should be interpreted as an illustration and example of the overall scope of alternative embodiments that ordinary skill in the art will recognize, which are implied by the included content, structurally and / or functionally equivalent to the included content, or become obvious in other ways based on the included content, and are not limited to those embodiments that are clearly depicted and / or described.

Claims

1. A magnetless synchronous electric motor having reconfigurable rotor poles and stator poles, comprising: a stator comprising a plurality of stator windings wound around a plurality of circumferentially spaced apart stator projections, wherein a first stator winding arrangement of the stator windings is wound relative to a first stator projection arrangement of the circumferentially spaced apart stator projections and a second stator winding arrangement of the stator windings is wound relative to a second stator projection arrangement of the circumferentially spaced apart stator projections; a rotor comprising a plurality of rotor windings wound around a plurality of circumferentially spaced apart rotor protrusions, wherein a first rotor winding arrangement of the rotor windings is wound relative to a first rotor protrusion arrangement of the circumferentially spaced apart rotor protrusions and a second rotor winding arrangement of the rotor windings is wound relative to a second rotor protrusion arrangement of the circumferentially spaced apart rotor protrusions; and A power transmission circuit is configured to control the polarity and / or phase sequence of the excitation current used in exciting the first and second stator windings and the rotor winding and the stator poles and rotor poles generated thereby, respectively.

2. The magnetless synchronous electric motor according to claim 1, wherein: The power transmission circuit is operable to provide a first number of stator poles by: providing the first stator winding arrangement with a polarity and a phase sequence of an excitation current of the first stator winding arrangement having a first polarity and a first phase sequence, respectively; and The second stator winding arrangement is provided with a polarity and a phase sequence of an excitation current of the second stator winding arrangement having the first polarity and the second phase sequence, respectively.

3. The magnetless synchronous electric motor according to claim 2, wherein: The power transmission circuit is operable to provide the second number of stator poles by: providing the first stator winding arrangement with a polarity and a phase sequence of an excitation current of the first stator winding arrangement having the first polarity and a third phase sequence, respectively; and The second stator winding arrangement is provided with a polarity and a phase sequence of an excitation current of the second stator winding arrangement having a second polarity and a fourth phase sequence, respectively, which are opposite to the first polarity.

4. The magnetless synchronous electric motor according to claim 3, wherein: The stator winding includes a first branch, a second branch, a third branch, a fourth branch, a fifth branch and a sixth branch; The first stator winding arrangement includes the first branch, the fourth branch and the fifth branch; The second stator winding arrangement comprises the second branch, the third branch and the sixth branch.

5. The magnetless synchronous electric motor according to claim 4, wherein: The first phase sequence includes phase A, phase B and phase C, wherein the first branch receives the phase A, the fourth branch receives the phase B, and the fifth branch receives the phase C; The second phase sequence includes an A' phase, a B' phase, and a C' phase, wherein the second branch receives the A' phase, the third branch receives the B' phase, and the sixth branch receives the C' phase; The third phase sequence includes the A phase, the B phase, and the C phase, wherein the first branch receives the A phase, the fourth branch receives the C phase, and the fifth branch receives the B phase; and The fourth phase sequence includes the A′ phase, the B′ phase, and the C′ phase, wherein the second branch receives the A′ phase, the third branch receives the C′ phase, and the sixth branch receives the B′ phase.

6. The magnetless synchronous electric motor according to claim 5, wherein: The first polarity corresponds to a positive polarity; and The second polarity corresponds to negative polarity.

7. The magnetless synchronous electric motor according to claim 1, wherein: The power transfer circuit is operable to provide a first number of the rotor poles by: providing the first rotor winding arrangement with a polarity of the excitation current of the first rotor winding arrangement having a first polarity; and The polarity of the field current of the second rotor winding arrangement is provided to the second rotor winding arrangement with the first polarity.

8. The magnetless synchronous electric motor according to claim 7, wherein: The power transfer circuit is operable to provide a second number of the rotor poles by: providing the first rotor winding arrangement with a polarity of the excitation current of the first rotor winding arrangement having the first polarity; and The polarity of the field current of the second rotor winding arrangement is provided to the second rotor winding arrangement with a second polarity opposite to the first polarity.

9. An electric machine with reconfigurable machine poles, comprising: a stator having a plurality of stator windings arranged into a first stator branch, a second stator branch, a third stator branch, a fourth stator branch, a fifth stator branch, and a sixth stator branch; a rotor having a plurality of rotor windings arranged into a first rotor branch and a second rotor branch; A power delivery circuit configured to: providing a first number of machine poles by delivering a field current having a first polarity and a first phase sequence to the first, fourth and fifth stator branches, delivering a field current having the first polarity and a second phase sequence to the second, third and sixth stator branches, and delivering a field current having the first polarity to the first rotor branch and delivering a field current having the first polarity to the second rotor branch; A second number of machine poles is provided by delivering an excitation current having the first polarity and a third phase sequence to the first, fourth and fifth branches, delivering an excitation current having a second polarity and a fourth phase sequence to the second, third and sixth branches, delivering an excitation current having the first polarity to the first rotor branch and delivering an excitation current having the second polarity to the second rotor branch.

10. A means of transport, comprising: an electric motor configured to convert electrical power into mechanical power for the purpose of propelling the vehicle; and Wherein, the electric motor comprises: a stator comprising a first stator winding arrangement and a second stator winding arrangement; a rotor comprising a first rotor winding arrangement and a second rotor winding arrangement; and A power transmission circuit is configured to control the polarity and / or phase sequence of the excitation current used in exciting the first and second stator windings and the rotor winding and the stator poles and rotor poles generated thereby, respectively.

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