Multi-sector slotted permanent magnet hybrid Vernier magnetoresistive motor

Abstract

The application discloses a multi-sector slot permanent magnet mixed excitation cursor magnetoresistive motor, which comprises a rotor, a concentrated armature winding, a stator and a permanent magnet; the rotor and the stator are both salient pole structures, the stator is provided with stator teeth facing the rotor, an air gap exists between the stator teeth and the rotor, modulation slots are formed on the rotor teeth, the rotor and the stator are both made of magnetic conductive material, the permanent magnet is arranged on the stator, and the concentrated armature winding is arranged on the stator teeth; wherein the concentrated armature winding is arranged according to a multi-sector three-phase structure, each sector is provided with a group of independent three-phase armature windings, and independent three-phase sinusoidal currents with DC bias are input into the three-phase armature windings of each sector; compared with a traditional three-phase motor, the motor has good fault tolerance while ensuring high torque density, the modulation slots are used to weaken the harmonic torque to the maximum extent to ensure stable operation of the motor, control is more flexible, and the motor is more applied to high-power low-speed large-torque transmission systems.

Description

Technical Field

[0001] This invention belongs to the field of motor manufacturing and control technology, specifically relating to a multi-sector slot permanent magnet hybrid excitation vernier reluctance motor. Background Technology

[0002] With the rapid development of the electric vehicle industry, there is an urgent need for technologies such as high-power operation and flexible control of motors. Due to its advantages such as fast torque response and high efficiency, and the fact that its transmission system does not require mechanical transmission devices, direct-drive motors have become an important development trend in the power source of modern electric vehicles. However, environmental conditions are constantly changing during actual motor operation; therefore, the design of direct-drive motors should fully consider efficient operation throughout the entire drive cycle. Specifically, the motor should have high torque density during low-speed startup, low torque ripple during stable operation, and superior field-weakening capability during high-speed operation.

[0003] In recent years, various motor topologies, serving as the power source for electric vehicles, have attracted the research attention of numerous scholars both domestically and internationally. Built-in permanent magnet motors generate torque comprising both permanent magnet torque and reluctance torque, and their superior torque density and field-weakening control capabilities have garnered widespread interest. However, due to the presence of numerous harmonic components in their unloaded air gap magnetic field, the generated torque exhibits significant ripple, which is detrimental to stable motor operation. Surface-mounted permanent magnet motors have largely solved this problem; through rational configuration of pole-slot combinations, they can simultaneously achieve high torque density and low torque ripple. However, due to the absence of salient pole effect, field-weakening operation remains a significant challenge. In contrast, vernier reluctance motors represent a more advanced motor topology, exhibiting high torque density characteristics due to their inherent magnetic gear effect, thus attracting extensive research. However, their armature inductance is relatively larger than that of built-in and surface-mounted permanent magnet motors, resulting in a lower power factor. In order to improve the performance of vernier reluctance motors, expand their application scope, effectively increase their torque density, enhance their fault tolerance, and make them more suitable for low-speed, high-torque requirements. Summary of the Invention

[0004] The purpose of this invention is to improve the performance of a vernier reluctance motor, effectively increase its torque density, enhance its fault tolerance, and better meet the requirements of low speed and high torque. This invention provides a multi-sector slotted permanent magnet hybrid vernier reluctance motor. Specifically, the invention divides the motor into multiple sectors, each with an independent three-phase armature winding. A three-phase sinusoidal current with DC bias is injected into each sector's independent three-phase armature winding. Therefore, the motor torque is essentially the sum of the torques corresponding to the pole-slot combinations in each sector, resulting in a higher torque density and better meeting the requirements of low speed and high torque. Furthermore, even if the armature winding in one sector fails, the windings in the other two sectors can still drive the motor to operate stably, significantly improving fault tolerance. In addition, research has found that due to the modulation effect of rotor teeth and stator slots on the air gap permeability, the two rotating magnetic fields contain a large number of harmonics in addition to the fundamental component. To minimize the impact of harmonic fields on torque performance, the invention incorporates a modulation slot on each rotor tooth, thereby utilizing the principle of magnetic field modulation to minimize harmonic torque and further ensure stable motor operation.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A multi-sector slot permanent magnet hybrid vernier reluctance motor includes at least: a rotor, a centralized armature winding, a stator, and permanent magnets;

[0007] Both the rotor and the stator are salient pole structures. The stator has stator teeth facing the rotor, and the rotor has rotor teeth facing the stator. Modulation slots are formed on the rotor teeth. There is an air gap between the stator teeth and the rotor. Both the rotor and the stator are made of magnetically conductive material. The permanent magnet is disposed on the stator and is tangentially magnetized. The magnetization direction is alternately distributed along the circumference. The centralized armature winding is disposed on the stator teeth.

[0008] The centralized armature winding is arranged in a multi-sector three-phase structure, with the number of sectors being greater than or equal to 2.

[0009] Each sector contains at least three sets of centralized armature windings, which serve as the U phase, V phase, and W phase, respectively, thus forming an independent three-phase armature winding. An independent three-phase sinusoidal current with DC bias is supplied to the three-phase armature windings of each sector.

[0010] When a three-phase sinusoidal current is passed through the armature winding of each sector, a rotating magnetic field is generated in the air gap. The interaction between the armature magnetic field and the permanent magnet magnetic field produces an electromagnetic torque with reluctance properties, thereby driving the rotor to rotate. However, due to the modulation effect of the rotor teeth and stator slots on the air gap permeability, the two rotating magnetic fields contain a large number of harmonics in addition to the fundamental component. The number of pole pairs, rotational speed, and amplitude of these harmonic rotating magnetic fields are related to the harmonic order; the higher the harmonic order, the smaller the amplitude, the higher the number of pole pairs, and the higher the rotational speed. These existing harmonic fields are the main cause of torque ripple. To minimize the impact of harmonic fields on torque performance, the technical solution of this invention provides a modulation slot on each rotor tooth. The principle is to reduce the amplitude of the harmonic field by adjusting the distribution of magnetic permeability in the air gap.

[0011] Further optionally, the number of sectors is 3, the amplitude and phase of the injected current in the same phase winding of each sector are the same, while the amplitude of the injected current between different phase windings is equal and the phase difference is 120°.

[0012] The technical solution of this invention divides the motor into multiple sectors, each sector containing an independent set of three-phase armature windings and passing a three-phase sinusoidal current with DC bias, so that each sector can independently drive the motor to operate stably.

[0013] Alternatively, the optimal size of the modulation groove is determined according to the following process:

[0014] The expression for rotor permeability is constructed by performing Fourier decomposition on the waveform of rotor permeability.

[0015] The expression for the armature magnetomotive force is obtained by performing Fourier decomposition on the armature winding magnetomotive force waveform.

[0016] The expression for the magnetomotive force of a permanent magnet is obtained by performing Fourier decomposition on the waveform of the permanent magnet.

[0017] Multiply the expression for armature magnetomotive force by the expression for rotor permeability to obtain the expression for armature magnetic flux density;

[0018] Multiplying the permanent magnet magnetomotive force expression by the rotor permeability expression yields the permanent magnet magnetic flux density expression.

[0019] The optimal size of the modulation slot is determined based on the armature magnetic flux density expression and the permanent magnet magnetic flux density expression.

[0020] The optimal size of the modulation slot aims to minimize the armature current magnetic flux density harmonics and permanent magnet magnetic flux density harmonics, excluding the fundamental magnetic flux density that generates stable torque (the fundamental armature current magnetic flux density and the fundamental permanent magnet magnetic flux density rotating at synchronous speed).

[0021] Further optionally, the expression for the armature magnetic flux density is:

[0022]

[0023] The magnetic flux density expression of the permanent magnet is:

[0024]

[0025] in,

[0026] In the formula, For armature magnetic flux density, For the magnetic flux density of a permanent magnet, S UVW M UVWi Defined intermediate variable, F PMk γ is the amplitude of each harmonic of the permanent magnet magnetomotive force, γ is the mechanical position angle of the motor air gap, ω is the rotor electric angular velocity, t is time, Λ0 is the fundamental component of the rotor magnetic permeability, and Λ rn Let α be the amplitude of each harmonic component, n be the rotor permeability harmonic order, and α be the amplitude of each harmonic component. rt For rotor tooth radii, α ms The modulated groove radius is k, the harmonic order of the permanent magnet magnetomotive force is Λ. h This represents the ideal value of the rotor's magnetic permeability;

[0027] The optimal size of the modulation slot is such that the amplitude Λ of each harmonic component is maximized. rn A modulation slot that converges rapidly with increasing harmonic order n satisfies: α rt =3α ms .

[0028] The technical solution of this invention derives the expressions for armature magnetic flux density and permanent magnet magnetic flux density, thereby minimizing torque ripple from the perspective of motor body design and determining the optimal size of the modulation slot to reduce torque ripple to the lowest possible level.

[0029] Alternatively, the three-phase armature windings of each sector may be Y-connected;

[0030] The neutral point is connected to the node of the upper half-bridge arm of the frequency converter via a diode, and to the node of the lower half-bridge arm of the frequency converter via a self-switching element.

[0031] Further optionally, each stator tooth has protruding teeth on both sides, and the permanent magnet is disposed on the protruding teeth of two adjacent stator teeth.

[0032] Alternatively, the rotor is located outside the stator.

[0033] Alternatively, the rotor may employ a straight slot or a skewed slot structure.

[0034] Further optionally, the multi-sector slot permanent magnet hybrid reluctance motor has an 18-slot stator and a 15-pole rotor structure.

[0035] Beneficial effects

[0036] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0037] 1. The permanent magnet hybrid vernier reluctance motor provided by the present invention adopts a multi-sector three-phase structure, that is, the motor is divided into multiple sectors, each sector is equipped with an independent three-phase armature winding, and a three-phase sinusoidal current with DC bias is injected into the independent three-phase armature winding of each sector. Thus, the motor torque is equivalent to the superposition of the torque corresponding to the pole-slot combination of each sector, so the torque density is greater and better meets the requirements of low speed and high torque. In addition, since each sector has an independent control function, even if the armature winding of one sector fails, the windings of the other two sectors can still drive the motor to run stably, greatly improving the fault tolerance and high operational reliability.

[0038] 2. The technical solution of this invention, through research, discovered that due to the modulation effect of rotor teeth and stator slots on the air gap magnetic permeability, the two rotating magnetic fields contain a large number of harmonics in addition to the fundamental component. To minimize the impact of harmonic fields on torque performance, the technical solution of this invention provides a modulation slot on each rotor tooth, thereby utilizing the principle of magnetic field modulation to weaken harmonic torque and further ensure the stable operation of the motor. Simultaneously, a method for determining the optimal size of the modulation slot is provided. Based on the motor structure, expressions for armature magnetic flux density and permanent magnet magnetic flux density are derived, thus determining the optimal size of the modulation slot. The theoretical derivation based on the motor structure further ensures the reliability of the optimal size of the modulation slot, minimizing harmonic torque to the greatest extent. Attached Figure Description

[0039] Figure 1 A schematic diagram of the structure of the three-sector slotted permanent magnet hybrid vernier reluctance motor provided by the present invention;

[0040] The attached figures are labeled as follows: 1, rotor; 2, concentrated armature winding; 3, stator; 4, permanent magnet.

[0041] Figure 2 This is a schematic diagram of the three-phase armature winding structure of each sector in the three-sector slotted permanent magnet hybrid reluctance motor provided by the present invention.

[0042] Figure 3 The waveforms of the opposite electromotive forces of the three-slot permanent magnet hybrid reluctance motor provided by the present invention.

[0043] Figure 4 The waveform diagram of rotor magnetic permeability distribution for each sector.

[0044] Figure 5 The waveform diagram shows the distribution of armature current magnetomotive force in each sector.

[0045] Figure 6 The waveform diagram of the magnetomotive force distribution of the permanent magnet in each sector.

[0046] Figure 7 Waveforms of back electromotive force when injected with different DC bias currents.

[0047] Figure 8 This represents the motor's output torque under different DC bias currents. Detailed Implementation

[0048] The present invention will be further described below with reference to embodiments.

[0049] Example 1:

[0050] The multi-sector slotted permanent magnet hybrid reluctance motor provided in this embodiment has a three-sector, three-phase structure, such as... Figure 1 As shown, the three-slot permanent magnet hybrid reluctance motor of this embodiment includes at least a rotor 1, a centralized armature winding 2, a stator 3, and a permanent magnet 4. Both the rotor 1 and the stator 3 have salient pole structures. The rotor 1 is located outside the stator 3, and preferably, the rotor 1 has a straight slot or skew slot structure. The stator 3 has stator teeth facing the rotor 1, and there is an air gap between the stator teeth and the rotor 1. A modulation slot is formed on each rotor tooth. Both the rotor 1 and the stator 3 are made of magnetically conductive material. Each stator tooth has protruding teeth on both sides. The permanent magnet 4 is disposed on the protruding teeth of two adjacent stator teeth and is tangentially magnetized, with the magnetization direction alternating along the circumference. The centralized armature winding 2 is disposed on the stator teeth, i.e., it spans across the stator teeth.

[0051] One of the core aspects of this invention is the creation of modulation slots on each rotor tooth. This will be described in detail below.

[0052] Another core feature of this invention is the adoption of a three-sector structure. In this embodiment, the three-sector slot permanent magnet hybrid reluctance motor adopts an 18-slot stator and a 15-pole rotor structure, with each sector containing 6 stator slots and 5 rotor poles; the three-phase armature windings of sector 1 are concentrated winding u1, concentrated winding v1, and concentrated winding w1, the three-phase armature windings of sector 2 are concentrated winding u2, concentrated winding v2, and concentrated winding w2, and the three-phase armature windings of sector 3 are concentrated winding u3, concentrated winding v3, and concentrated winding w3. In this configuration, concentrated windings u1, u2, and u3 serve as the windings for phase U in each sector; concentrated windings v1, v2, and v3 serve as the windings for phase V in each sector; and concentrated windings w1, w2, and w3 serve as the windings for phase W in each sector. Therefore, each sector contains at least three sets of concentrated armature windings, forming an independent three-phase armature winding. This allows for the injection of independent three-phase sinusoidal current with DC bias into the three-phase armature windings of each sector, enabling each sector to independently drive the motor to rotate stably.

[0053] The working mechanism of the three-sector slot permanent magnet hybrid reluctance motor of the present invention is as follows: following the principle of minimum reluctance, that is, the magnetic flux always closes along the magnetic circuit with the minimum reluctance. When a three-phase sinusoidal current is passed through the three-phase armature winding of each sector, a rotating magnetic field will be generated in the air gap. The interaction between the armature magnetic field and the permanent magnet magnetic field will generate an electromagnetic torque with reluctance properties, thereby driving the rotor 1 to rotate.

[0054] Figure 2 This is a schematic diagram of the three-phase armature winding structure of each sector of the three-sector slotted permanent magnet hybrid reluctance motor in this embodiment of the invention. As shown in the diagram, the three-phase armature windings in each sector adopt a Y-connection. The neutral point is connected to the node of the upper half-bridge arm of the frequency converter via a diode, and to the node of the lower half-bridge arm of the frequency converter via a self-switching element. This connection method allows the DSP to control the on / off state of the self-switching element, thereby controlling the magnitude of the DC bias current. Assuming that the resistance of each winding is the same, the current flowing into the same phase winding of each sector has the same amplitude and phase, while the currents in different phase windings have equal amplitudes but a phase difference of 120°.

[0055] Figure 3 The diagram shows the back electromotive force (EMF) waveforms of the three-sector slotted permanent magnet hybrid reluctance motor of this invention. Since the U, V, and W phases of each sector are located at the same electrical angle, the back EMF waveforms of the same phase in each sector are in phase. The expression for the armature current in each sector can be represented as follows:

[0056]

[0057] in, I represents the three-phase armature currents (including three-phase AC and DC bias currents) of sector s, where s is the sector number, with values ​​of 1, 2, and 3; ac I is the effective value of the armature current. dc ω is the applied DC bias current; ω is the electric angular velocity of rotor 1.

[0058] The permanent magnet 4 of this three-sector slot permanent magnet hybrid reluctance motor generates a magnetic field along the tangential magnetization, which passes through the air gap, rotor 1, two adjacent stator teeth, and the stator yoke between them to form a closed loop. By adjusting the DC bias current I... dc The magnitude of the torque can be changed by altering the magnitude of the permanent magnet's magnetic field, which in turn changes the motor's back electromotive force, ultimately achieving torque regulation and speed control. It is worth noting that, based on the armature winding distribution, the magnetic field generated by the DC bias current is radially and uniformly distributed within the motor, resulting in minimal coupling between them and minimal impact on the motor's normal operation.

[0059] Based on the above, it can be seen that the three-sector slotted permanent magnet hybrid vernier reluctance motor provided in Embodiment 1 of the present invention is powered by three independent sets of three-phase sinusoidal AC power with DC bias. Even if the armature winding of one sector fails, the three-phase armature windings of the other two sectors can still drive the motor to run stably, greatly improving its fault tolerance. Therefore, this motor possesses the advantages of high torque density and strong fault tolerance of multiphase motors. To adjust the torque, the DC bias current I is adjusted. dc Size.

[0060] It should be understood that in other feasible embodiments, the division of the number of sectors (equal division, uniform distribution) and the number of poles of stator 3 and rotor 1 can be adaptively adjusted according to actual needs. Specifically, when determining the number of poles of stator 3 and rotor 1, the prerequisite for stable motor rotation must be met: the number of pole pairs and the rotational speed of the rotating magnetic field generated by the permanent magnet 4 and the rotating magnetic field generated by the armature current during rotor 1 rotation should be equal. In other feasible embodiments, the connection method of the three-phase armature windings and the arrangement of the permanent magnets on the stator teeth can be adaptively adjusted and combined with other technical features of the present invention.

[0061] The following section will describe another core optimization of the present invention: modulation grooves are formed on each rotor tooth.

[0062] Due to the modulation effect of rotor teeth and stator slots on the air gap magnetic permeability, the two rotating magnetic fields contain a large number of harmonics in addition to the fundamental component. The number of pole pairs, rotational speed, and amplitude of these harmonic rotating magnetic fields are related to the harmonic order; the higher the harmonic order, the smaller the amplitude, the higher the number of pole pairs, and the higher the rotational speed. These existing harmonic fields are the main cause of torque ripple. In order to minimize the impact of harmonic fields on torque performance, this embodiment of the invention provides a small slot (modulation slot) on each rotor tooth. The principle is to reduce the amplitude of the harmonic field by adjusting the distribution of magnetic permeability in the air gap.

[0063] In order to minimize the impact of harmonic fields on torque performance and to weaken harmonic torque to the greatest extent, the present invention preferentially adopts the following method to determine the optimal size of the modulation slot.

[0064] Assume the air permeability is 0 and neglect core saturation. Due to the DC bias current I... dc Its function is merely to adjust the magnetic field of the permanent magnet, and from the perspective of the overall structure of the motor, its impact on the armature current is minimal. Therefore, the DC bias current I will not be considered in the following analysis. dc The function of this is that, since the three sectors are symmetrically distributed, only one sector needs to be considered. According to... Figure 1 The motor structure in the diagram allows for the qualitative drawing of the rotor magnetic permeability waveform for each sector, as shown below. Figure 4 As shown, the magnetomotive force waveform generated by the three-phase current in each sector is as follows: Figure 5 As shown, the magnetomotive force waveform generated by the permanent magnet in each sector is as follows: Figure 6 As shown. Performing Fourier decomposition on the waveforms yields:

[0065] 1) The expression for rotor permeability is:

[0066]

[0067] In the formula, Λ r (γ,ωt) is the expression for rotor permeability, where γ is the mechanical position angle of the air gap, ω is the rotor electrical angular velocity, t is time, Λ0 is the fundamental component of rotor permeability, and Λ rn Let α be the amplitude of each harmonic component, n be the rotor permeability harmonic order, and α be the amplitude of each harmonic component. rt For rotor tooth radii, α ms To adjust the arc of the groove.

[0068] 2) The expression for the three-phase current magnetomotive force (armature current magnetomotive force) of each sector is:

[0069]

[0070] In the formula, For the three-phase current magnetomotive force (armature winding magnetomotive force), S UVWN is an intermediate variable defined. c M represents the number of turns in the phase winding. UVWi Let ξ be an intermediate variable defined by ξ, i be the harmonic order of armature current magnetomotive force, r be any positive integer, and N be a positive integer.

[0071] 3) The expression for the magnetomotive force of a permanent magnet is:

[0072]

[0073] In the formula, For the magnetomotive force of a permanent magnet, F PMk α represents the amplitude of each harmonic of the magnetomotive force of the permanent magnet. PM For the radian of the permanent magnet, F PMm denoted as the ideal value of the magnetomotive force of the permanent magnet, and k is the harmonic order of the magnetomotive force of the permanent magnet.

[0074] Based on the principle of magnetic circuit calculation, the magnetic flux density distribution under different operating conditions can be calculated:

[0075] 1) Magnetic flux density distribution under three-phase current The expression:

[0076]

[0077] 2) Magnetic flux density distribution when a permanent magnet is in operation The expression:

[0078]

[0079] The harmonic components of the rotating magnetic field and the static magnetic field components are the main sources of torque ripple. Formulas (5) and (6) show that a stable torque can only be generated when the number of fundamental magnetic flux density pole pairs is equal when three-phase current is applied and when a permanent magnet is applied. To minimize torque ripple from the perspective of motor design, the goal is to minimize magnetic flux density harmonics. In this embodiment, according to the above formulas, to minimize torque ripple, Λ rn The value of can converge at the fastest speed as n increases, making it particularly important to reasonably determine the size of the modulation slot. According to equation (2), let α rt =3α ms This can minimize torque ripple.

[0080] Figure 7 and Figure 8 The figures show the back EMF waveforms and output torque of the motor with the modulation slot under different DC bias current injections. As can be seen from the figures, the motor's torque performance is good due to the introduction of the modulation slot. It can be proven that the total output torque of the motor is the algebraic sum of the motor's output torque when each sector is powered individually.

[0081] In summary, the technical solution of this invention adopts a multi-sector three-phase structure, so the motor torque is equivalent to the superposition of the torques corresponding to the pole-slot combinations of each sector, resulting in a higher torque density and better meeting the requirements of low speed and high torque. Even if the armature winding of one sector fails, the windings of the other two sectors can still drive the motor to run stably, greatly improving fault tolerance and operational reliability. Furthermore, the problem of large torque ripple in the stator permanent magnet motor is mitigated by setting modulation slots on the rotor teeth.

[0082] It should be emphasized that the examples described in this invention are illustrative rather than limiting. Therefore, this invention is not limited to the examples described in the specific embodiments. Any other embodiments derived by those skilled in the art based on the technical solutions of this invention, without departing from the spirit and scope of this invention, whether modifications or substitutions, are also within the protection scope of this invention.

Claims

1. A multi-sector slotted permanent magnet hybrid vernier reluctance motor, characterized in that: At least including: Rotor, concentrated armature winding, stator, and permanent magnets; Both the rotor and the stator are salient pole structures. The stator has stator teeth facing the rotor, and the rotor has rotor teeth facing the stator. Modulation slots are formed on the rotor teeth. There is an air gap between the stator teeth and the rotor. Both the rotor and the stator are made of magnetically conductive material. The permanent magnet is disposed on the stator and is tangentially magnetized. The magnetization direction is alternately distributed along the circumference. The centralized armature winding is disposed on the stator teeth. The centralized armature winding is arranged in a multi-sector three-phase structure, with the number of sectors being greater than or equal to 2. If the number of sectors is 3, the expression for armature magnetic flux density is: ； The expression for the magnetic flux density of a permanent magnet is: ； in, , ; In the formula, For armature magnetic flux density, For permanent magnet magnetic flux density, , Defined intermediate variables, The amplitudes of the harmonics of the magnetomotive force of the permanent magnet are given. This refers to the mechanical position angle of the motor's air gap. The rotor's electric angular velocity, t For time, This is the fundamental component of the rotor's magnetic permeability. Here, n represents the amplitude of each harmonic component, and n is the rotor permeability harmonic order. The harmonic sequence of the armature current magnetomotive force. For rotor tooth radii, The modulated groove radius is given by k, where k is the harmonic order of the permanent magnet magnetomotive force. This represents the ideal value of the rotor's magnetic permeability; The optimal size of the modulation slot is such that the amplitude of each harmonic component is... A modulation slot that converges rapidly as the harmonic order n increases satisfies: ; Each sector contains at least three sets of centralized armature windings, which serve as the U phase, V phase, and W phase, respectively, thus forming an independent three-phase armature winding. An independent three-phase sinusoidal current with DC bias is supplied to the three-phase armature windings of each sector.

2. The multi-sector slotted permanent magnet hybrid reluctance motor according to claim 1, characterized in that: There are 3 sectors. The amplitude and phase of the injected current in the same phase winding of each sector are the same, while the amplitude of the injected current between different phase windings is equal and the phase difference is 120°.

3. The multi-sector slotted permanent magnet hybrid reluctance motor according to claim 1, characterized in that: The optimal size of the modulation groove is determined according to the following process: The expression for rotor permeability is constructed by performing Fourier decomposition on the waveform of rotor permeability. The expression for the armature magnetomotive force is obtained by performing Fourier decomposition on the armature winding magnetomotive force waveform. The expression for the magnetomotive force of a permanent magnet is obtained by performing Fourier decomposition on the waveform of the permanent magnet. Multiply the expression for armature magnetomotive force by the expression for rotor permeability to obtain the expression for armature magnetic flux density; Multiplying the permanent magnet magnetomotive force expression by the rotor permeability expression yields the permanent magnet magnetic flux density expression. The optimal size of the modulation slot is determined based on the armature magnetic flux density expression and the permanent magnet magnetic flux density expression. The optimal size of the modulation slot is to minimize the armature current magnetic flux density harmonics and permanent magnet magnetic flux density harmonics, excluding the fundamental magnetic flux density that generates stable torque.

4. The multi-sector slotted permanent magnet hybrid reluctance motor according to any one of claims 1-3, characterized in that: The three-phase armature windings of each sector are connected in a Y-type configuration; The neutral point is connected to the node of the upper half-bridge arm of the frequency converter via a diode, and to the node of the lower half-bridge arm of the frequency converter via a self-switching element.

5. The multi-sector slotted permanent magnet hybrid reluctance motor according to any one of claims 1-3, characterized in that: Each stator tooth has protruding teeth on both sides, and the permanent magnet is disposed on the protruding teeth of two adjacent stator teeth.

6. The multi-sector slotted permanent magnet hybrid reluctance motor according to any one of claims 1-3, characterized in that: The rotor is located outside the stator.

7. The multi-sector slotted permanent magnet hybrid reluctance motor according to any one of claims 1-3, characterized in that: The rotor adopts a straight slot or oblique slot structure.

8. The multi-sector slotted permanent magnet hybrid reluctance motor according to any one of claims 1-3, characterized in that: The multi-sector slot permanent magnet hybrid reluctance motor has an 18-slot stator and a 15-pole rotor structure.

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