Magnet auxiliary winding rotor for electric motor

Abstract

Aspects of the present disclosure relate to an electric motor including a rotor having both permanent magnets and operable coils. The coils of the rotor are operable to generate a temporary magnetic field that supplements the permanent magnetic field of the permanent magnets. Accordingly, the amount of torque output by the rotor can be controlled by operating the coil of the rotor on demand.

Description

[0001] introduction

[0002] The present disclosure relates generally to the automotive, manufacturing and industrial equipment fields. More particularly, the present disclosure relates to an electric motor having a magnet assisted winding rotor. Summary of the invention

[0003] The present specification as a whole relates to an electric motor including a rotor having both permanent magnets and operable coils. The coils of the rotor can be operated to generate a temporary magnetic field that supplements the magnetic field of the permanent magnets. Thus, the amount of torque output by the rotor can be controlled by operating the coils of both the stator and the rotor as needed.

[0004] According to one or more aspects of the present disclosure, a rotor for an electric motor includes: a body configured to rotate about a central axis; permanent magnets located within the body and circumferentially spaced apart from each other about the central axis; and rotor coils within the body, wherein each of the rotor coils forms a winding segment that is circumferentially positioned between corresponding adjacent pairs of the permanent magnets.

[0005] According to one or more aspects of the present disclosure, an electric motor includes a stator including stator coils configured to generate a rotating magnetic field; and a rotor configured to rotate around a central axis and including: permanent magnets that are circumferentially spaced apart from each other around the central axis, wherein circumferentially adjacent permanent magnets among the permanent magnets generate different permanent magnetic fields relative to the central axis; and rotor coils that form winding segments, wherein each group of winding segments circumferentially located between corresponding adjacent pairs of permanent magnets is configured to receive current and generate a temporary magnetic field that supplements the different permanent magnetic fields of the corresponding adjacent pairs of permanent magnets.

[0006] According to one or more aspects of the present disclosure, a method includes operating stator coils of a stator to generate a rotating magnetic field that extends through a rotor including permanent magnets and rotor coils, wherein the permanent magnets of the rotor generate a permanent magnetic field; determining a demand for torque; and if the demand for torque is above a threshold, operating the rotor coils of the rotor to generate a temporary magnetic field that supplements the permanent magnetic field of the permanent magnets. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Certain features of the subject technology are set forth in the appended claims. However, for purposes of explanation, several embodiments of the subject technology are set forth in the following figures.

[0008] Figure 1 A perspective cross-sectional view of an example electric motor is shown in accordance with one or more implementations of the subject technology.

[0009] Figure 2 One or more specific implementations of the subject technology are shown. Figure 1A cross-sectional view of a portion of an electric motor.

[0010] Figure 3 A cross-sectional view of a portion of a rotor is shown in accordance with one or more implementations of the subject technology.

[0011] Figure 4 A cross-sectional view of a portion of a rotor is shown in accordance with one or more implementations of the subject technology.

[0012] Figure 5 A cross-sectional view of a portion of an electric machine in accordance with one or more implementations of the subject technology is shown.

[0013] Figure 6 One or more specific implementations of the subject technology are shown. Figure 5 A cross-sectional view of a portion of an electric motor.

[0014] Figure 7 A cross-sectional view of a portion of an electric machine in accordance with one or more implementations of the subject technology is shown.

[0015] Figure 8 One or more specific implementations of the subject technology are shown. Figure 7 A cross-sectional view of a portion of an electric motor.

[0016] Fig. 9 A cross-sectional view of a portion of an electric machine in accordance with one or more implementations of the subject technology is shown.

[0017] Fig.10 One or more specific implementations of the subject technology are shown. Fig. 9 A cross-sectional view of a portion of an electric motor.

[0018] Fig.11 A cross-sectional view of a portion of an electric machine in accordance with one or more implementations of the subject technology is shown.

[0019] Fig.12 One or more specific implementations of the subject technology are shown. Fig.11 A cross-sectional view of a portion of an electric motor.

[0020] Fig.13 Graphs illustrating motor torque output at various rotor winding activity levels in accordance with one or more implementations of the subject technology.

[0021] Fig.14 A flow chart is shown of an example process for operating an electric motor in accordance with one or more implementations of the subject technology.

[0022] Fig.15An electronic system is shown in which one or more implementations of the subject technology may be implemented. DETAILED DESCRIPTION

[0023] The specific embodiments set forth below are intended to be described as various configurations of the subject technology, and are not intended to represent the only configurations that can practice the subject technology. The accompanying drawings are incorporated herein and constitute a part of the specific embodiments. The specific embodiments include specific details in order to provide a thorough understanding of the subject technology. However, the subject technology is not limited to the specific details set forth herein, and one or more other specific implementations can be used to practice. In one or more specific implementations, well-known structures and components are shown in block diagram form to avoid confusion to the concepts of the subject technology.

[0024] The present specification as a whole relates to an electric motor including a rotor having both permanent magnets and operable coils. The coils of the rotor can be operated to generate a temporary magnetic field that supplements the permanent magnetic field of the permanent magnets. Thus, the amount of torque output by the rotor can be controlled by operating the coils of both the stator and the rotor as needed.

[0025] Permanent magnets, such as heavy rare earth (HRE) magnets, can be expensive, particularly in response to demand and supply issues. As the supply of such permanent magnets is limited and demand increases, the cost can also increase over time. Therefore, it may be beneficial to provide a machine with the ability to reduce reliance on permanent magnets. Furthermore, by providing a wound rotor winding for the rotor of the motor, performance can be controlled to meet output demand despite the reduction of permanent magnets.

[0026] Thus, motors such as those described herein can provide high performance characteristics while using fewer and / or smaller magnets. Such motors can also have flexible and adaptive control parameters that allow them to adjust operating conditions to match requirements. In particular, when the demand for torque is low, the stator and / or rotor excitation can be controlled to maximize the efficiency of the motor.

[0027] In certain embodiments, the electric machines described herein may include features of synchronous electric machines. However, it will be appreciated that one or more features of the present disclosure may be applied to one of a variety of electric machine types, including synchronous electric machines, permanent magnet synchronous electric machines (PMSMs), line-start synchronous electric machines (LSSMs), line-start permanent magnet electric machines (LSPMMs), and the like.

[0028] refer to Figure 1 , an electric motor may include a stator and a rotor for providing a rotational output on a shaft. Figure 1 is a partial perspective view of the electric machine 10 having the stator 110 and the rotor 150 .

[0029] In some embodiments, such as Figure 1 As shown, the electric machine 10 may include a generally cylindrical rotor shaft 12 concentrically surrounded by a cylindrical rotor 150. As used herein, "cylindrical" and "annular" refer to a structure having a generally circular inner cross-sectional shape and a possibly generally circular outer cross-sectional shape, but this outer cross-sectional shape may vary to some extent, with flat or irregular areas. The rotor shaft 12 and the rotor 150 are configured to rotate concentrically in unison about a common central axis 20, potentially at high revolutions per minute (RPM). The rotor 150 may be made of electrical steel. The rotor shaft 12 may be made of steel and / or other possible metals or metal alloys.

[0030] The electric machine 10 may include a stator 110 including stator coils 120 configured to generate a rotating magnetic field. The rotating magnetic field may be generated by passing a multi-phase current through the stator coils 120. The stator coils 120 may form segments of windings distributed around a rotor 150. For example, Figure 1 As shown, the stator coil 120 may form a plurality of segments, each segment extending in a direction substantially parallel to the central axis 20 of the rotor 150. The rotating magnetic field generated by the stator 110 may rotate around the central axis 20 of the rotor 150. Neither the stator 110 nor the stator coil 120 need to move to generate a rotating magnetic field. For example, the coil may be operated with alternating current, with different segments having currents of different directions and / or magnitudes at any given moment. When the current direction and / or magnitude of each segment of the stator coil 120 changes over time, the magnetic field generated in its vicinity may change accordingly. Therefore, the resulting magnetic field may be characterized as a standing wave magnetic field rotating around the central axis 20 (e.g., having an alternating magnetic field direction extending circumferentially around the central axis 20). The rotating magnetic field may further extend through the rotor 150, which may include permanent magnets 160 and rotor coils 170. The rotating magnetic field generated by the stator 110 may interact magnetically with such components of the rotor 150 to cause the rotor 150 to rotate around the central axis 20.

[0031] The end windings (e.g., crown end windings and / or welded end windings) of the stator coils 120 of the stator 110 may be a conductive material, such as copper or another suitable metal or material. The end windings of the stator coils 120 may protrude axially beyond the rotor 150 and / or concentrically surround the rotor 150. The end windings of the stator coils 120 are connected in parallel and / or in series with each other to form a set of windings having multi-phase terminals that are operably connected to a controller, such as a processing unit of an electronic system described elsewhere herein.

[0032] The rotor shaft 12 and / or the rotor 150 may rotate with a first bearing assembly 25 disposed at a first end of the rotor shaft 12 and a second bearing assembly 27 disposed at a second end of the rotor shaft 12. Thus, when the rotor 150 and / or the rotor shaft 12 respond to the rotating magnetic field generated by the stator 110, the rotor and / or the rotor shaft may rotate about the central axis 20. The rotor shaft 12 may provide a torque output accordingly. Such an output may be detected, for example, by a sensor of an electronic system described further herein.

[0033] The rotor coil 170 may form a winding segment 172 of its winding that extends within the rotor 150. For example, Figure 1 As shown, the rotor coils 170 may form winding segments 172, each of which extends in a direction generally parallel to the central axis 20 of the rotor 150. Additionally or alternatively, the winding segments 172 may extend longitudinally in a direction generally parallel to the segments of the stator coils 120. Each winding segment 172 may extend to or toward one or both of the longitudinal ends of the rotor 150. For example, a given winding segment 172 may extend longitudinally within the body of the rotor 150 and connect to another winding segment 172 on a circumferentially adjacent pole of the rotor 150. In this way, the winding segments 172 may form a winding that extends both parallel to the central axis 20 and through the central axis 20 to form one or more loops. One or more end windings 174 may be disposed at one or more ends of the rotor 150. Each of the end windings 174 of the rotor coils 170 can be operably connected to a controller, such as a processing unit of an electronic system described further herein. In some embodiments, the end windings 174 can be connected to a power source via one or more brushes (not shown) so that the rotor 150 and rotor coils 170 can rotate while the power source and / or control circuitry provides power (e.g., current) without rotation. Such brushes can also provide a substantially uniform current to the rotor coils 170 so that the resulting temporary magnetic field can be maintained as desired during rotation of the rotor 150. Thus, the end windings 174 can be connected (e.g., using brushes) in a manner that facilitates rotation and direct current (DC) through the rotor coils 170.

[0034] Reference now Figure 2 , the stator and rotor can interact to provide a rotational output. Figure 2 A portion of the motor 10 is shown, but it will be appreciated that the portion shown may be part of a pattern that is repeated circumferentially around the central axis to form a continuous cylindrical structure. The pattern may be repeated in any number of cycles, such that the illustrated example is not limited to the arrangement shown.

[0035] In some embodiments, such as Figure 2As shown, the stator 110 may include a stator body 112 and a stator coil 120. The stator coil 120 and / or its segments may be positioned in a stator coil chamber 126 formed in the stator body 112. The stator coil chamber 126 may form an opening 128 at a radially inner side of the stator body 112 facing the rotor 150. The opening 128 may guide the magnetic field generated by the stator coil 120 toward the rotor 150. The magnetic field may be shaped at least in part by the geometry of the stator body 112.

[0036] In some embodiments, such as Figure 2 As further shown, the rotor 150 may include a rotor body 152, permanent magnets 160, and rotor coils 170. In some embodiments, the permanent magnets 160 may be positioned within magnet chambers 166 formed within the rotor body 152. The rotor body 152 defines a cover portion 154, each of which is radially disposed between a corresponding one of the plurality of magnet chambers 166 and the radially outermost side of the rotor 150. The cover portion 154 may hold the permanent magnets 160 in place when the rotor 150 rotates. The magnet chambers 166 may be distributed so that the permanent magnets 160 may be circumferentially spaced apart from each other around the central axis.

[0037] In some embodiments, the rotor coil 170 and / or its segments may be positioned within a rotor coil chamber 156 formed within the rotor body 152. The rotor coil chamber 156 may form an opening 158 at a radially outer side of the rotor body 152 facing the stator 110. For example, the rotor body 152 may define the openings 158 such that each opening 158 is radially disposed between a corresponding one of the plurality of coil chambers 156 and the radially outermost side of the rotor 150. The openings 158 may guide the magnetic field generated by the rotor coil 170 toward the stator 110. The magnetic field may be shaped at least in part by the geometry of the rotor body 152.

[0038] As described herein, the stator coils 120 may be operated to generate a rotating magnetic field. For example, the stator coils 120 may be operated with alternating current, with different segments having currents of different directions and / or magnitudes at any given moment. As the direction and / or magnitude of the current in each segment of the stator coils 120 changes over time, the magnetic field generated in its vicinity may change accordingly. The rotating magnetic field may extend through the rotor 150 to magnetically couple to the field generated by the permanent magnets 160 and / or the rotor coils 170. The rotating magnetic field generated by the stator 110 may interact magnetically with such components of the rotor 150 to cause the rotor 150 to rotate.

[0039] Reference now Figure 3It will be appreciated that the permanent magnets 160 may be provided in any arrangement, position, orientation, and / or number. For example, the permanent magnets 160 may have different sizes to fit within the magnet chamber 166 of the rotor 150 to reduce the reverse electromagnetic force. In some embodiments, such as Figure 3 As shown, each magnet chamber 166 may include a plurality of permanent magnets 160. A group of permanent magnets 160 within one of the plurality of magnet chambers 166 may be circumferentially staggered relative to each other within the corresponding magnet chamber 166. Additionally or alternatively, the permanent magnets 160 in a given magnet chamber 166 and / or in different magnet chambers 166 may have different sizes, shapes, materials, magnetic properties, etc. Although one magnet chamber 166 is shown as being circumferentially located between a given pair of circumferentially adjacent rotor coils 170, any number of magnet chambers 166 and / or permanent magnets may be disposed between a pair of circumferentially adjacent rotor coils 170.

[0040] Reference now Figure 4 , the rotor coil 170 may be arranged to generate a temporary magnetic field. Figure 4 As shown in , the rotor coils 170 may each include one or more winding segments 172 that are grouped together in a corresponding one of the coil chambers 156 defined by the rotor body 152. For example, the rotor coils 170A and 170B may each form a plurality of winding segments 172A and 172B, respectively, that are circumferentially positioned between corresponding adjacent pairs of permanent magnets 160. By way of further example, a winding segment 172A within a given coil chamber 156 may each be connected to a corresponding one of the winding segments 172A within an adjacent coil chamber 156 to form a loop having a plurality of turns (N), thereby forming a rotor coil 170A having N turns that extend through adjacent pairs of coil chambers 56. Such a rotor coil 170A may further extend around and / or proximate to a corresponding one of the magnets 160. As shown in FIG. Figure 4As shown, the first winding segment 172A of the first rotor coil 170A can extend longitudinally in each of the corresponding pair of coil chambers 156 of the rotor 150 and be connected to the other first winding segment 172A of the same first rotor coil 170A in the other coil chamber 156 on the circumferentially adjacent permanent magnet 160. One or more of the winding segments 172A of one rotor coil 170A can optionally be connected to the other winding segment 172B of the adjacent rotor coil 170B. In this way, each rotor coil 170A or 170B can be formed by component segments (e.g., 172A or 172B, respectively) that are wound in a ring, spiral and / or helix to the circumferentially opposite sides of the corresponding permanent magnet 160. In addition, the coil segments on different (e.g., circumferentially adjacent) sides of a given permanent magnet 160 can provide current in opposite directions, such as current in opposite directions parallel to the central axis. Such flow can facilitate the generation of a temporary magnetic field that supplements the permanent magnetic field generated by the permanent magnet 160.

[0041] In some embodiments, while each of the rotor coils 170 of the rotor 150 (e.g., the first rotor coil 170A, the second rotor coil 170B, etc.) can form one or more loops around the corresponding permanent magnet 160, the individual rotor coils 170 can be electrically connected to provide current and generate a magnetic field as desired. For example, one or both terminals of a given rotor coil 170 (e.g., the first rotor coil 170A, the second rotor coil 170B, etc.) can be electrically connected to the terminals of another rotor coil 170 (such as a circumferentially adjacent rotor coil 170). Thus, the individual rotor coils 170 can be connected in series to provide current (e.g., from a power supply) therethrough. Thus, the individual rotor coils 170 can be connected in parallel to provide current (e.g., from a power supply) therethrough. It will be understood that the rotor coils 170 can be connected in series and / or in parallel.

[0042] A set of winding segments 172 within one of the plurality of coil chambers 156 may be radially or otherwise staggered relative to each other within a corresponding rotor coil chamber 156. Additionally or alternatively, the winding segments 172 within a given coil chamber 156 and / or different rotor coil chambers 156 may be of different sizes, shapes, materials, etc. Although one coil chamber 156 is shown as being circumferentially located between a given pair of circumferentially adjacent permanent magnets 160, any number of coil chambers 156 and / or rotor coils 170 may be disposed between a pair of circumferentially adjacent permanent magnets 160. Additionally, any number of turns and / or winding segments 172 may be provided within a given coil chamber 156.

[0043] Reference now Figure 5 , the permanent magnets of the rotor can provide a magnetic field for coupling to the rotating magnetic field of the stator. Figure 5As shown, the stator coils 120 of the stator 110 can be operated to generate a rotating magnetic field 138. For example, the stator coils 120 can be operated with variable current, with different segments having currents of different directions and / or magnitudes at any given moment. When the current direction and / or magnitude of each segment of the stator coil 120 changes over time, the magnetic field 138 generated in the vicinity thereof can change accordingly. The rotating magnetic field 138 can extend through the rotor 150 to magnetically couple to the permanent magnets 160 ( Figure 5 ) and / or rotor coil 170 ( Figure 6 The rotating magnetic field 138 generated by the stator 110 may magnetically interact with such components of the rotor 150 to cause the rotor 150 to rotate.

[0044] like Figure 5 As shown in addition, the permanent magnets 160 can be distributed in different circumferential positions relative to each other. The permanent magnets 160 may have different magnetic orientations. For example, circumferentially adjacent permanent magnets in the permanent magnets 160 may have different (e.g., opposite) magnetic orientations relative to the central axis. By way of another example, some permanent magnets 160 may have a north-south magnetic orientation so that the permanent magnetic field 168 extending therethrough points to the central axis, and some permanent magnets 160 may have a north-south magnetic orientation so that the permanent magnetic field 168 extending therethrough points away from the central axis. It will be understood that each magnetic field can form a closed loop so that some parts of the magnetic field can be oriented in any given direction. However, references to the orientation of the permanent magnets herein refer to the magnetic orientation of the corresponding permanent magnets and adjacent to the corresponding permanent magnets.

[0045] Reference now Figure 6 , the rotor coils may be arranged so that when operated, they generate a temporary magnetic field that supplements the permanent magnetic field from the permanent magnets. Figure 6 As shown, the rotor coils 170 may form winding segments, wherein each set of winding segments or other portions of a given rotor coil 170 may be circumferentially located between corresponding adjacent pairs of permanent magnets 160. Such rotor coils 170 may be operated to receive current and generate a temporary magnetic field 178. Figure 6 As shown, each temporary magnetic field 178 may have a different permanent magnetic field 168 (eg, Figure 5As shown in the figure, each of the permanent magnetic fields 178 is aligned with each other. For example, each of the rotor coils 170 can be arranged and operated to receive an electric current and generate a temporary magnetic field 178 that extends through each of the permanent magnets in the corresponding adjacent pairs of permanent magnets 160. The portion of the temporary magnetic field 178 that extends through each of the permanent magnets in the corresponding adjacent pairs of permanent magnets 160 can be aligned with the corresponding permanent magnetic field generated by the corresponding adjacent pairs of permanent magnets 160. As used herein, if the overlapping partial components of two magnetic fields each have a component that is parallel to the other, then the magnetic field is aligned with another magnetic field. It will be understood that the entirety of such portions does not have to be parallel. Instead, the components can be parallel so that representative field lines will form an angle of less than 90 degrees at the intersection. As used herein, if the resulting combined magnetic field when combined is stronger than either magnetic field alone, then one magnetic field complements another magnetic field. For example, as Figure 6 As shown in FIG. 1 , the temporary magnetic field 178 (including its Figure 5 The density and number of magnetic field lines of the permanent magnetic field 168 shown in FIG. 1 are greater than those of the permanent magnetic field 168 shown in FIG. 1 . Figure 5 168 . Such an arrangement may allow the permanent magnetic field 168 and the temporary magnetic field 178 to combine (e.g., constructively interfere) in a manner that generates a combined magnetic field that is stronger than either one alone. This may also allow the permanent magnets 160 and the rotor coils 170 to be more strongly magnetically coupled to corresponding portions of the rotating magnetic field 138 generated by the stator 110 than the permanent magnets 160 alone (i.e., without the operation of the rotor coils 170).

[0046] Reference now Figure 7 and Figure 8 Another arrangement of permanent magnets and rotor coils can provide a permanent magnetic field and / or a temporary magnetic field for coupling to the rotating magnetic field of the stator. Figure 7 As shown, a plurality (e.g., 2 or more) of permanent magnets 160 may be grouped together between a circumferentially adjacent pair of rotor coils 170. For example, each group of permanent magnets 160 may include constituent permanent magnets 160 having different positions and / or orientations relative to each other. As an example, Figure 7 Adjacent permanent magnets 160 in the group may be tilted or otherwise arranged to form an angle relative to each other. The permanent magnets 160 within the group may optionally have symmetry across an axis, such as an axis that intersects the central axis of the rotor 150. The permanent magnets 160 within the group may have similar magnetic orientations to generate a combined permanent magnetic field 168. In some embodiments, circumferentially adjacent groups of permanent magnets 160 may have different (e.g., opposite) magnetic orientations relative to the central axis. It will be understood that the permanent magnets 160 and their groups may be provided with any arrangement, position and / or orientation to shape the resulting permanent magnetic field 168.

[0047] like Figure 8As shown, the rotor coils 170 may form winding segments, wherein each set of winding segments or other portions of a given rotor coil 170 may be circumferentially located between corresponding adjacent pairs of permanent magnets 160. Such rotor coils 170 may be operated to receive current and generate a temporary magnetic field 178, which may have a different permanent magnetic field 168 ( Figure 7 1 . It will be appreciated that the rotor coils 170 may be provided in any arrangement, position and / or orientation to shape the resulting temporary magnetic field 178.

[0048] Reference now Fig. 9 and Fig.10 Another arrangement of permanent magnets and coils can provide a permanent magnetic field and / or a temporary magnetic field for coupling to the rotating magnetic field of the stator. Fig. 9 As shown, a plurality of (e.g., 2 or more) permanent magnets 160 may be grouped together near adjacent rotor coils 170. For example, each group (e.g., a pair) of permanent magnets 160 may include constituent permanent magnets 160 located on opposite sides of an opening 158 in the rotor body 152 of the rotor 150. Such permanent magnets 160 may additionally be radially adjacent to (e.g., overlapped with) the corresponding coils 170. For example, a permanent magnet 160 may be radially adjacent to a rotor coil 170, rather than being located between two circumferentially adjacent rotor coils 170. The permanent magnets 160 within a group (e.g., the permanent magnets adjacent to a given rotor coil 170) may have similar magnetic orientations to generate a combined permanent magnetic field 168. In some embodiments, circumferentially adjacent groups of permanent magnets 160 (e.g., each group adjacent to a corresponding coil 170) may have different (e.g., opposite) magnetic orientations relative to the central axis. It will be understood that the permanent magnets 160 and their groups may be provided with any arrangement, position, and / or orientation to shape the resulting permanent magnetic field 168.

[0049] like Fig.10 As shown, the rotor coils 170 may form winding segments, wherein each set of winding segments or other portions of a given rotor coil 170 may be circumferentially adjacent to a corresponding set of permanent magnets 160. Such rotor coils 170 may be operated to receive current and generate a temporary magnetic field 178, which may have a different permanent magnetic field 168 ( Fig. 9 1 . It will be appreciated that the rotor coils 170 may be provided in any arrangement, position and / or orientation to shape the resulting temporary magnetic field 178.

[0050] Reference now Fig.11 and Fig.12 Another arrangement of permanent magnets and coils can provide a permanent magnetic field and / or a temporary magnetic field for coupling to the rotating magnetic field of the stator. Fig.11 and Fig.12 As shown, the permanent magnets 160 can be distributed at different circumferential positions relative to each other. Fig.11 and Fig.12 One arrangement is shown in FIG, but it will be appreciated that any arrangement of permanent magnets 160 may be provided, including the arrangement shown herein. Fig.11 and Fig.12 As further shown, the rotor coils 170 may form winding segments, wherein each set of winding segments or other portions of a given rotor coil 170 may be circumferentially adjacent to a corresponding permanent magnet 160. Multiple (e.g., two or more) rotor coils 170 may be positioned on opposite (e.g., circumferential) sides of a given permanent magnet 160.

[0051] The rotor coils 170 may be operated in different modes to generate different magnetic fields. For example, any given pair of rotor coils 170 on opposite sides of the corresponding permanent magnets 160 may receive magnetic fields of the same direction ( Fig.11 ) or different (e.g., opposite) directions ( Fig.12 By way of further example, any given pair of rotor coils 170 between a circumferentially adjacent pair of permanent magnets 160 may receive currents in different (eg, opposite) directions ( Fig.11 ) or the same direction ( Fig.12 ) on the rotor coils. By way of further example, the direction of the current may be parallel to the central axis. It will be understood that such coils may be independently controlled to receive current in either direction as desired. Therefore, the rotor coils 170 do not need to be connected in series or in parallel with each other, but may be independently controlled as desired (e.g., by a power supply). The rotor coils 170 may generate a temporary magnetic field 178 that may have a portion of each of the different permanent magnetic fields that complement the permanent magnets 160. It will be understood that the rotor coils 170 may be provided with any arrangement, position, orientation, and / or mode of operation to shape the resulting temporary magnetic field 178. For example, depending on the direction and / or magnitude of the current passing through each rotor coil 170 and / or which rotor coils 170 are operated, different current directions may shape the resulting temporary magnetic field 178 in different ways. In this way, the rotor coils 170 may affect the permanent magnetic field of the permanent magnets 160 in various ways to generate a desired magnetic field.

[0052] Reference now Fig.13, the torque output of the motor can be controlled based on the operation of the rotor coil described herein. For example, different situations (such as situation 1, situation 2, situation 3 and situation 4) correspond to different current amounts provided to the rotor coil of the rotor during the generation of the rotating magnetic field from the stator. At the lowest torque output (i.e., situation 4), no current is provided to the rotor coil. In this way, only the permanent magnetic field of the permanent magnet is used to magnetically couple the rotor to the rotating magnetic field from the stator. In other cases (i.e., situation 1 with 15A, situation 2 with 10A and situation 3 with 5A), a non-zero amount of current is provided to the rotor coil. The current in situation 2 is higher than the current provided in situation 3, and the current in situation 1 is higher than the current provided in situation 2. The torque values ​​and the average values ​​of these values ​​that vary over time are all shown in the graph. It will be understood that the current amounts disclosed herein are merely exemplary, and any current amounts can be provided, including values ​​between or outside those values ​​disclosed herein. As shown, as the current amount increases, the torque increases accordingly. The temporary magnetic field generated by the rotor coil supplements the permanent magnetic field from the permanent magnet. This increases the strength of the magnetic coupling with the rotating magnetic field. Thus, even against resistance, torque can be increased to improve output. Such torque output can be provided in response to a demand for torque (or increased torque), as described elsewhere herein. For example, the rotor coils can be operated to provide the torque output required to meet the torque demand.

[0053] Fig.14 A flow chart of an example process 800 for operating an electric motor according to one or more implementations of the subject technology is shown. Figure 1 and Figure 2 Motor 10, Figure 3 to Figure 4 The rotor 150, Figures 5 to 12 Process 800 is described with reference to an electric machine and / or its various components. However, process 800 is not limited to Figure 1 and Figure 2 The motor 10 and / or Figure 3 to Figure 4 The rotor 150, Figures 5 to 12 A motor, and one or more blocks (or operations) of process 800 may be performed by Figure 1 and Figure 2 The motor 10 and / or Figure 3 to Figure 4 The rotor 150, Figures 5 to 12 The process 800 may be performed by one or more other structural components of a motor and / or other suitable device, equipment or system. In addition, for the purpose of explanation, some frames of process 800 are described herein as occurring continuously or linearly. However, multiple frames of process 800 may occur in parallel. In addition, the frames of process 800 do not need to be performed in the order shown, and / or one or more frames of process 800 do not need to be performed and / or may be replaced by other operations.

[0054] In box 802, the motor (e.g., by a processor) can be operated to generate a rotating magnetic field. The rotating magnetic field can be generated by passing a current through each of a plurality of stator coils, and the plurality of stator coils have winding segments distributed around the rotor of the motor. The rotating magnetic field generated by the stator can rotate around the central axis of the rotor. The rotating magnetic field can further extend through the rotor, which may include permanent magnets and rotor coils. The permanent magnets of the rotor generate a permanent magnetic field, which can respond to the rotating magnetic field by rotating the rotor so that the permanent magnetic field from the permanent magnets remains aligned with the corresponding part of the rotating magnetic field. Therefore, the permanent magnets of the rotor can be coupled to the rotating magnetic field magnetism from the stator.

[0055] In box 804, the demand for torque can be determined (e.g., by a processor). The demand for torque can be based on input from a control unit, user input, etc. For example, a processor or other control unit can determine the output (e.g., torque) to be provided by a shaft coupled to a rotor. By way of another example, a user can operate an input device such as an accelerator, a pedal, etc. to determine the desired output of the motor and / or shaft. In some embodiments, the demand for torque can be determined as the presence and / or amount of torque that is higher than the torque that can be provided based on the magnetic coupling between the rotating magnetic field and the permanent magnet. It can be determined based on detected conditions (e.g., using a sensor) and / or predicted output (e.g., based on a prediction model) based on a prediction model).

[0056] At block 806, the demand for torque may be determined (e.g., by a processor) to be above or below a threshold. The threshold may be based on the current output of the motor (e.g., at an axis) and / or a desired amount of torque. For example, the output of the motor (e.g., torque) may be determined and compared to a target output (e.g., torque) to determine whether the current output meets the demand for torque. If the demand for torque is determined to be below or at a threshold (i.e., not above a threshold), process 800 may return to block 804 and / or another operation and / or process. If it is determined that the demand for torque is above a threshold, process 800 may proceed to block 808.

[0057] At block 808, the rotor coils of the rotor may be operated (e.g., by a processor) to generate a temporary magnetic field. The temporary magnetic field may be generated in a manner that supplements the permanent magnetic field of the permanent magnet. For example, when the rotor coils are operated, each of the temporary magnetic fields may extend through each permanent magnet in a corresponding adjacent pair of permanent magnets. The portion of each temporary magnetic field that extends through each permanent magnet in a corresponding adjacent pair of permanent magnets may be aligned with a corresponding permanent magnetic field generated by a corresponding adjacent pair of permanent magnets.

[0058] Fig.15 An example electronic system 900 is shown in which aspects of the present disclosure may be implemented. The electronic system 900 may be used to provide reference Figures 1 to 4 Any electronic device that may and / or may be a part of the described features and execution processes includes, but is not limited to, vehicles, computers, servers, smart phones, and wearable devices (e.g., authentication devices). Electronic system 900 may include various types of computer-readable media and interfaces for various other types of computer-readable media. Electronic system 900 includes persistent storage device 902, system memory 904 (and / or buffer), input device interface 906, output device interface 908, sensor 910, ROM 912, processing unit 914, network interface 916, bus 918, and / or subsets and variations thereof.

[0059] The bus 918 collectively represents a plurality of internal devices and / or components (such as Figure 1 and Figure 2 Motor 10, Figure 3 to Figure 4 The rotor 150, Figures 5 to 12 918 is a bus that is used to communicate with the ECU 204 and / or any of its various components. In one or more implementations, the bus 918 communicatively connects the one or more processing units 914 to the ROM 912, the system memory 904, and the persistent storage device 902. From these various memory units, the one or more processing units 914 retrieve instructions to be executed and data to be processed in order to perform the processes disclosed in the present subject matter. In different implementations, the one or more processing units 914 can be a single processor or a multi-core processor. In one or more implementations, one or more of the processing units 914 can be included on the ECU 204, such as in the form of a processor 206.

[0060] ROM 912 stores static data and instructions required by one or more processing units 914 and other modules of the electronic system 900. On the other hand, the persistent storage device 902 can be a read-write memory device. The persistent storage device 902 can be a non-volatile memory unit that stores instructions and data even when the electronic system 900 is turned off. In one or more specific implementations, a mass storage device (such as a magnetic disk or optical disk and its corresponding disk drive) can be used as the persistent storage device 902.

[0061] In one or more specific implementations, a removable storage device (such as a floppy disk, a flash drive, and its corresponding disk drive) may be used as the persistent storage device 902. Similar to the persistent storage device 902, the system memory 904 may be a read-write memory device. However, unlike the persistent storage device 902, the system memory 904 may be a volatile read-write memory, such as RAM. The system memory 904 may store any instructions and data that one or more processing units 914 may need at run time. In one or more specific implementations, the processes disclosed in the present subject matter are stored in the system memory 904, the persistent storage device 902, and / or the ROM 912. From these various memory units, the one or more processing units 914 retrieve instructions to be executed and data to be processed in order to perform the processes of one or more specific implementations.

[0062] The persistent storage device 902 and / or the system memory 904 may include one or more machine learning models. Machine learning models (such as those described herein) are often used to form predictions, solve problems, identify objects in image data, and the like. For example, the machine learning models described herein may be used to predict whether an authorized user is approaching a vehicle and intends to open a charging port closure. Various specific implementations of machine learning models are possible. For example, the machine learning model may be a deep learning network, a transformer-based model (or other attention-based model), a multilayer perceptron or other feedforward network, a neural network, and the like. In various examples, the machine learning model may be more adaptive because the machine learning model may be improved over time by retraining the model as additional data becomes available.

[0063] The bus 918 is also connected to an input device interface 906 and an output device interface 908. The input device interface 906 enables a user to communicate information and select commands to the electronic system 900. The input device that can be used with the input device interface 906 may include, for example, an alphanumeric keyboard, a touch screen, and a pointing device. The output device interface 908 may enable the electronic system 900 to communicate information to the user. For example, the output device interface 908 may provide a display of an image generated by the electronic system 900. The output device that can be used with the output device interface 908 may include, for example, a printer and a display device, such as a liquid crystal display (LCD), a light emitting diode (LED) display, an organic light emitting diode (OLED) display, a flexible display, a flat panel display, a solid state display, a projector, or any other device for outputting information.

[0064] One or more implementations may include a device that acts as both an input and output device, such as a touch screen. In these implementations, the feedback provided to the user may be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; the input from the user may be received in any form, including acoustic, voice, or tactile input.

[0065] Bus 918 is also connected to sensor 910. Sensor 910 may include a position sensor that can be used to determine the device location based on positioning technology. For example, the position sensor can provide GNSS positioning, wireless access point positioning, cellular phone signal positioning, Bluetooth signal positioning, image recognition positioning, and / or one or more of an inertial navigation system (e.g., via a motion sensor such as an accelerometer and / or a gyroscope). In one or more specific implementations, sensor 910 can be used to detect the movement, travel, and orientation of electronic system 900. For example, the sensor may include a torque sensor, a resolver, an accelerometer, a rate gyroscope, and / or other motion-based sensors. Sensor 910 may include one or more biometric sensors and / or image sensors for authenticating users.

[0066] Bus 918 also couples electronic system 900 to one or more networks and / or one or more network nodes via one or more network interfaces 916. In this manner, electronic system 900 may be part of a computer network, such as a local area network or a wide area network. Any or all components of electronic system 900 may be used in conjunction with the subject disclosure.

[0067] Implementations within the scope of the present disclosure may be implemented in part or in whole using a tangible computer-readable storage medium (or multiple tangible computer-readable storage media of one or more types) encoding one or more instructions. Tangible computer-readable storage media may also be non-transitory in nature.

[0068] Computer-readable storage media can be any storage media that can be read, written, or otherwise accessed by a general or special computing device, including any processing electronics and / or processing circuitry capable of executing instructions. For example, but not limited to, computer-readable media can include any volatile semiconductor memory, such as RAM, DRAM, SRAM, T-RAM, Z-RAM, and TTRAM. Computer-readable media can also include any non-volatile memory, such as ROM, PROM, EPROM, EEPROM, NVRAM, flash memory, nvSRAM, FeRAM, FeTRAM, MRAM, PRAM, CBRAM, SONOS, RRAM, NRAM, racetrack memory, FJG, and Millipede memory.

[0069] In addition, the computer-readable storage medium may include any non-semiconductor memory, such as optical disk storage, magnetic disk storage, magnetic tape, other magnetic storage devices, or any other medium capable of storing one or more instructions. In one or more specific implementations, the tangible computer-readable storage medium may be directly coupled to the computing device, while in other specific implementations, the tangible computer-readable storage medium may be indirectly coupled to the computing device, for example, via one or more wired connections, one or more wireless connections, or any combination thereof.

[0070] Instructions can be directly executable or can be used to develop executable instructions. For example, instructions can be implemented as executable or non-executable machine code, or can be implemented as instructions of high-level languages ​​that can be compiled to produce executable or non-executable machine code. In addition, instructions can also be implemented as data or can include data. Computer executable instructions can also be organized in any format, including routines, subroutines, programs, data structures, objects, modules, applications, small applications, functions, etc. As recognized by those skilled in the art, the details including but not limited to the number, structure, sequence and organization of instructions can change significantly without changing the underlying logic, function, processing and output.

[0071] Although the above discussion mainly involves microprocessors or multi-core processors that execute software, one or more specific implementations are performed by one or more integrated circuits such as ASICs or FPGAs. In one or more specific implementations, such integrated circuits execute instructions stored on the circuit itself.

[0072] Unless otherwise specified, an element mentioned in the singular is not intended to represent one and only one, but one or more. For example, "a" module may refer to one or more modules. In the absence of further constraints, an element beginning with "a", "an", "the" or "said" does not exclude the presence of other identical elements.

[0073] Headings and subheadings, if any, are used for convenience only and do not limit the invention. The word exemplary is used to mean serving as an example or illustration. To the extent that the terms "including" or "having" and the like are used, such terms are intended to be inclusive in a manner similar to the term "comprising" as understood when "comprising" is used as a transitional word in a claim. Relational terms such as first and second and the like may be used to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions.

[0074] Phrases such as an aspect, this aspect, another aspect, some aspects, one or more aspects, a specific implementation, this specific implementation, another specific implementation, some specific implementations, one or more specific implementations, an embodiment, this embodiment, another embodiment, some embodiments, one or more embodiments, a configuration, this configuration, another configuration, some configurations, one or more configurations, subject technology, this disclosure, the present disclosure, other variations thereof, etc. are for convenience and do not imply that the disclosures associated with such phrases are necessary for the subject technology, or that such disclosures are applicable to all configurations of the subject technology. The disclosures associated with such phrases may be applicable to all configurations or one or more configurations. The disclosures associated with such phrases may provide one or more examples. Phrases such as an aspect or some aspects may refer to one or more aspects, and vice versa, and this is similarly applicable to other aforementioned phrases.

[0075] The phrase "at least one" preceding a list of items, with the terms "and" or "or" used to separate any of those items, modifies the list as a whole, rather than as each constituent item of the list. The phrase "at least one" does not require selection of at least one item; rather, the phrase allows for a meaning that includes at least one of any of those items, and / or at least one of any combination of those items, and / or at least one of each of those items. As an example, each of the phrases "at least one of A, B, and C" or "at least one of A, B, or C" means only A, only B, or only C; any combination of A, B, and C; and / or at least one of each of A, B, and C.

[0076] It should be understood that the specific order or level of the disclosed steps, operations or processes is an illustration of an exemplary method. Unless otherwise clearly stated, it should be understood that the specific order or level of steps, operations or processes can be performed in different orders. Some of the steps, operations or processes can be performed simultaneously. The attached method claims (if any) present the elements of various steps, operations or processes in a sample order, and are not meant to be limited to the specific order or level presented. These can be performed serially, linearly, in parallel or in different orders. It should be understood that the instructions, operations and systems described can usually be integrated together in a single software / hardware product or encapsulated in multiple software / hardware products.

[0077] Terms such as top, bottom, front, back, side, horizontal, vertical, etc. refer to an arbitrary reference frame, not the ordinary gravitational reference frame. Thus, such terms may extend upward, downward, diagonally, or horizontally in a gravitational reference frame.

[0078] The present disclosure is provided to enable any person skilled in the art to practice the various aspects described herein. In some instances, well-known structures and components are shown in block diagram form to avoid confusion with the various concepts of the subject technology. The present disclosure provides various examples of the subject technology, and the subject technology is not limited to these examples. Those skilled in the art will readily appreciate various modifications to these aspects, and the principles described herein may be applied to other aspects.

[0079] All structural and functional equivalents of the various aspects of the elements described throughout this disclosure are known or will become known to those of ordinary skill in the art, and these equivalents are expressly incorporated herein by reference and are intended to be included in the claims. In addition, nothing disclosed herein is intended to serve the public, regardless of whether such disclosure is explicitly stated in the claims. Any claim element should not be interpreted under the provisions of 35 U.S.C. § 112 (f) unless the element is explicitly stated using the phrase "means for..." or, in the case of a method claim, the phrase "step for..." is used to state the element.

[0080] Those skilled in the art will appreciate that the various illustrative frames, modules, elements, parts, methods and algorithms described herein can be implemented as hardware, electronic hardware, computer software or a combination thereof. In order to illustrate this interchangeability of hardware and software, various illustrative frames, modules, elements, parts, methods and algorithms have been generally described above in terms of their functionality. Whether this functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the entire system. Those skilled in the art can implement the described functionality in different ways for each specific application. Various parts and frames can be arranged differently (e.g., arranged in different orders or divided in different ways), all of which do not depart from the scope of this subject technology.

[0081] The names, figure descriptions, abstracts, and drawings are hereby incorporated into this disclosure and are provided as illustrative examples of the disclosure rather than as limiting descriptions. This document is submitted with the understanding that they will not be used to limit the scope or meaning of the claims. In addition, in the detailed description, it can be seen that for the purpose of simplifying the present disclosure, the description provides illustrative examples and various features are grouped together in various specific implementations. The method of the present disclosure should not be interpreted as reflecting an intention that the claimed subject matter requires more features than those expressly stated in each claim. On the contrary, as reflected in the claims, the inventive subject matter lies in less than all the features of a single disclosed configuration or operation. The claims are hereby incorporated into the detailed description, with each claim independently serving as a separately claimed subject matter.

[0082] The claims are not intended to be limited to the aspects described herein, but should be accorded the full scope consistent with the language of the claims and encompassing all legal equivalents. Nevertheless, none of the claims is intended to encompass subject matter that fails to satisfy the requirements of applicable patent law, nor should it be interpreted in such a manner.

Claims

1. A rotor for an electric motor, the rotor comprising: a body configured to rotate about a central axis; permanent magnets located within the body and circumferentially spaced from one another about the central axis; and a rotor coil within the body, wherein each of the rotor coils forms a winding segment that is circumferentially positioned between corresponding adjacent pairs of the permanent magnets, wherein each of the rotor coils is configured to receive an electric current and generate a temporary magnetic field extending through each permanent magnet in the corresponding adjacent pairs of the permanent magnets, wherein the portion of the temporary magnetic field extending through each permanent magnet in the corresponding adjacent pairs of the permanent magnets is aligned with the corresponding permanent magnetic field generated by the corresponding adjacent pairs of the permanent magnets. 2 . The rotor of claim 1 , wherein circumferentially adjacent ones of the permanent magnets have different magnetic orientations relative to the central axis. 3 . The rotor of claim 1 , wherein the body defines a plurality of magnet chambers, wherein each of the permanent magnets is disposed in a corresponding one of the plurality of magnet chambers. 4 . The rotor of claim 3 , wherein the body defines cover portions, each of the cover portions being radially disposed between a corresponding one of the plurality of magnet chambers and a radially outermost portion of the rotor.

5. The rotor of claim 3, wherein a set of the permanent magnets within a magnet chamber in the plurality of magnet chambers are circumferentially staggered relative to each other.

6. The rotor of claim 4, wherein the body further defines a plurality of coil chambers, wherein each of the rotor coils extends through corresponding pairs of the plurality of coil chambers, the corresponding pairs of the plurality of coil chambers being located on radially opposite sides of the central axis. 7 . The rotor of claim 6 , wherein the body defines openings, each of the openings being radially disposed between a corresponding one of the plurality of coil chambers and the radially outermost side of the rotor.

8. The rotor of claim 1 wherein the winding segments extend longitudinally within the body between opposite ends of the rotor.

9. A motor, comprising: a stator comprising stator coils configured to generate a rotating magnetic field; and A rotor configured to rotate about a central axis and comprising: permanent magnets, the permanent magnets being circumferentially spaced apart from each other about the central axis, wherein circumferentially adjacent ones of the permanent magnets generate different permanent magnetic fields relative to the central axis; and Rotor coils each forming a winding segment, wherein each group of the winding segments circumferentially located between corresponding adjacent pairs of the permanent magnets is configured to receive current and generate a temporary magnetic field that supplements the different permanent magnetic fields of the corresponding adjacent pairs of the permanent magnets. 10 . The electric machine of claim 9 , wherein the rotor includes a body defining a plurality of magnet chambers, wherein each of the permanent magnets is disposed in a corresponding one of the plurality of magnet chambers. 11 . The motor of claim 10 , wherein the body defines cover portions each of which is radially disposed between a corresponding one of the plurality of magnet chambers and a radially outermost portion of the rotor.

12. The electric machine of claim 10, wherein a group of the permanent magnets within a magnet chamber in the plurality of magnet chambers are circumferentially staggered relative to each other.

13. The electric machine of claim 11, wherein the body further defines a plurality of coil chambers, wherein each of the rotor coils extends through a corresponding pair of the plurality of coil chambers. 14 . The motor of claim 13 , wherein the body defines openings, each of the openings being radially disposed between a corresponding one of the plurality of coil chambers and the radially outermost side of the rotor.

15. The electric machine of claim 9, wherein segments of the stator coils extend longitudinally between opposite ends of the stator, and the winding segments of the rotor coils extend longitudinally between opposite ends of the rotor. 16 . The motor of claim 9 , wherein each of the rotor coils extends to radially opposite sides of the central axis.

17. A method comprising: operating stator coils of a stator to generate a rotating magnetic field extending through a rotor including permanent magnets and rotor coils, wherein the permanent magnets of the rotor generate a permanent magnetic field; Determine the torque requirement; and If the demand for torque is above a threshold, the rotor coils of the rotor are operated to generate a temporary magnetic field that supplements the permanent magnetic field of the permanent magnets.

18. A method according to claim 17, wherein when operating the rotor coil, each of the temporary magnetic fields extends through each permanent magnet in the corresponding adjacent pairs of the permanent magnets, and wherein the portion of each temporary magnetic field extending through each permanent magnet in the corresponding adjacent pairs of the permanent magnets is aligned with the corresponding permanent magnetic field generated by the corresponding adjacent pairs of the permanent magnets.

19. The method of claim 18, wherein circumferentially adjacent ones of the permanent magnets have different magnetic orientations relative to a central axis of the rotor.

20. The method of claim 17, wherein when the rotor coil is operated with an electric current, magnetic coupling between the rotor and the stator is stronger than when the rotor coil is not operated.

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