Motor rotor, motor and vehicle

Abstract

The invention provides a motor rotor, a motor and a vehicle, a rotor body comprises a rotor core and permanent magnets, a plurality of first permanent magnet slot groups and a plurality of second permanent magnet slot groups are formed on the rotor core, and the first permanent magnet slot groups and the second permanent magnet slot groups are arranged in a staggered manner along the circumferential direction of the rotor core; the first permanent magnet groove group comprises a first permanent magnet groove and a second permanent magnet groove which are symmetrical about the d axis and are arranged in a V shape, and the second permanent magnet groove group comprises a third permanent magnet groove and a fourth permanent magnet groove which are symmetrical about the d axis and are arranged in a V shape; the outer end of the first permanent magnet groove is communicated with the outer end of the fourth permanent magnet groove to form a first strip-shaped magnetic isolation groove, and the outer end of the second permanent magnet groove is communicated with the outer end of the third permanent magnet groove to form a second strip-shaped magnetic isolation groove; two first gaps and / or two second gaps are formed in the outer circle of the rotor iron core. The strip-shaped magnetic isolation grooves and the gaps can effectively optimize an air-gap harmonic magnetic field, reduce the harmonic distortion rate of the air-gap magnetic field, effectively inhibit iron loss at a high rotating speed, and improve the efficiency of the motor.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to structural improvement of motor rotors and corresponding motors and vehicles. Background Art

[0002] With the promotion of new energy vehicles, new energy electric vehicles are becoming more and more popular, and the market's requirements for electric vehicle endurance are getting higher and higher. At present, the endurance of new energy vehicles in urban conditions has reached a relatively high level, but the high-speed endurance is still at a relatively low level, usually only 60% to 70% in urban conditions. The reason for this is that in addition to the increase in energy consumption caused by the increase in wind resistance of the car at high speed, the low efficiency of the main drive motor at high speed is also one of the main reasons. As one of the core components of electric vehicles, how to expand the motor's high-efficiency zone to the high-speed range as much as possible (improve the motor's efficiency in the high-speed range) is a difficult problem that needs to be solved urgently.

[0003] The iron loss of the motor is mainly composed of hysteresis loss and eddy current loss, both of which are energy losses caused by the alternating magnetic field inside the iron core. The calculation formula for hysteresis loss is:

[0004] Among them, k h is a constant related to material properties, f is the alternating frequency of the magnetic field, B m is the maximum magnetic induction intensity, and n is an empirical constant.

[0005] The calculation formula for eddy current loss is:

[0006] Among them, k e is the eddy current loss coefficient, which is related to the resistivity, geometry and other factors of the material, f is the alternating frequency of the magnetic field, B m is the maximum magnetic induction intensity, and V is the volume of the conductor.

[0007] It can be seen from the above formula that when the proportion of harmonic magnetic field (especially high-order harmonic) in the air gap is higher, the alternating frequency f of the magnetic field is also greater, so the iron loss generated by the core is greater; when local magnetic flux saturation occurs in the core (local magnetic flux density is too high), the maximum magnetic induction intensity B m The larger it is, the greater the iron loss in the core.

[0008] When a permanent magnet synchronous motor is operating at high speed, it is usually necessary to apply a reverse weak magnetic current in the d-axis direction of the motor to reduce the load back electromotive force. Therefore, the armature reaction of the motor is more intense than that of the non-weakening magnetic condition, and the air gap magnetic field harmonics are significantly increased. The harmonic magnetic field will cause the motor iron loss to increase sharply, so the motor heats up seriously and the motor efficiency is low. Summary of the invention

[0009] The present invention provides a motor rotor, a motor and a vehicle to solve the problem of low motor efficiency of a permanent magnet synchronous motor under high speed working conditions in the prior art.

[0010] In order to achieve the above technical effects, the technical solution adopted by the motor rotor proposed in the present invention is:

[0011] A motor rotor comprises a rotor body, wherein the rotor body comprises:

[0012] A rotor core, wherein a plurality of first permanent magnet slot groups and a plurality of second permanent magnet slot groups are formed on the rotor core, wherein the first permanent magnet slot groups and the second permanent magnet slot groups are alternately arranged along the circumferential direction of the rotor core; the first permanent magnet slot group comprises a first permanent magnet slot and a second permanent magnet slot which are symmetrical about the d axis and arranged in a V shape, the second permanent magnet slot group comprises a third permanent magnet slot and a fourth permanent magnet slot which are symmetrical about the d axis and arranged in a V shape, the first permanent magnet slot is adjacent to the fourth permanent magnet slot, and the second permanent magnet slot is adjacent to the third permanent magnet slot; the first permanent magnet slot The outer end of the body slot is connected with the outer end of the fourth permanent magnet slot to form a first band-shaped magnetic isolation slot, the outer end of the second permanent magnet slot is connected with the outer end of the third permanent magnet slot to form a second band-shaped magnetic isolation slot, the first band-shaped magnetic isolation slot and the second band-shaped magnetic isolation slot respectively pass through the q-axis direction and are located in the outer circle area of ​​the rotor core; two first notches symmetrical about the d-axis are formed on the outer circle of the rotor core between the first permanent magnet slot and the second permanent magnet slot, and / or two second notches symmetrical about the d-axis are formed on the outer circle of the rotor core between the third permanent magnet slot and the fourth permanent magnet slot;

[0013] Permanent magnets are respectively installed in the first permanent magnet slot, the second permanent magnet slot, the third permanent magnet slot and the fourth permanent magnet slot.

[0014] The first permanent magnet slot group and the second permanent magnet slot group are asymmetric, and the first gap and the second gap are asymmetric.

[0015] The number of the first permanent magnet slots in each of the first permanent magnet slot groups is one, and the number of the second permanent magnet slots is one;

[0016] The number of the third permanent magnet slots in each of the second permanent magnet slot groups is one, and the number of the fourth permanent magnet slots is one.

[0017] The first permanent magnet slot includes a first inner permanent magnet slot and a first outer permanent magnet slot located outside the first inner permanent magnet slot, and the second permanent magnet slot includes a second inner permanent magnet slot and a second outer permanent magnet slot located outside the second inner permanent magnet slot; the first inner permanent magnet slot and the second inner permanent magnet slot are symmetric about the d-axis and arranged in a V shape, and the first outer permanent magnet slot and the second outer permanent magnet slot are symmetric about the d-axis and arranged in a V shape;

[0018] The third permanent magnet slot includes a third inner permanent magnet slot and a third outer permanent magnet slot located outside the third inner permanent magnet slot, and the fourth permanent magnet slot includes a fourth inner permanent magnet slot and a fourth outer permanent magnet slot located outside the fourth inner permanent magnet slot; the third inner permanent magnet slot and the fourth inner permanent magnet slot are symmetric about the d-axis and arranged in a V shape, and the third outer permanent magnet slot and the fourth outer permanent magnet slot are symmetric about the d-axis and arranged in a V shape;

[0019] The outer end of the first inner permanent magnet slot communicates with the outer end of the fourth inner permanent magnet slot to form the first strip-shaped magnetic isolation slot, and the outer end of the second inner permanent magnet slot communicates with the outer end of the third inner permanent magnet slot to form the second strip-shaped magnetic isolation slot;

[0020] Among the two first notches, one is located on the outer circumference of the rotor core between the first inner permanent magnet slot and the first outer permanent magnet slot, and the other is located on the outer circumference of the rotor core between the second inner permanent magnet slot and the second outer permanent magnet slot;

[0021] Among the two second notches, one is located on the outer circumference of the rotor core between the third inner permanent magnet slot and the third outer permanent magnet slot, and the other is located on the outer circumference of the rotor core between the fourth inner permanent magnet slot and the fourth outer permanent magnet slot.

[0022] The inner and outer diameters of the first strip-shaped magnetic isolation slot satisfy: 0 < R1 - R2 < 2.4 * gap, and the inner and outer diameters of the second strip-shaped magnetic isolation slot satisfy: 0 < R3 - R4 < 2.4 * gap;

[0023] Wherein, R1 is the outer diameter of the first strip-shaped magnetic isolation slot, R2 is the inner diameter of the first strip-shaped magnetic isolation slot, R3 is the outer diameter of the second strip-shaped magnetic isolation slot, R4 is the inner diameter of the second strip-shaped magnetic isolation slot, gap is the air gap of the motor, and 0 < gap < 2.

[0024] The length A2 of the permanent magnet in the first inner-layer permanent magnet slot satisfies: 0.65*(π / P - 2*D1 / R0)*R0 < A2 < 0.85*(π / P - 2*D1 / R0)*R0, where D1 is the distance from the outer end of the first inner-layer permanent magnet slot to the q-axis, P is the number of pole pairs of the motor, and R0 is the outer diameter of the rotor; the width B2 of the permanent magnet in the fourth inner-layer permanent magnet slot satisfies: 0.5*D1 < B2 < 1.5*D1; the angle V2 between the first inner-layer permanent magnet slot and the second inner-layer permanent magnet slot satisfies: 180° / P < V2 < 360° / P + 20°; the angle V4 between the third inner-layer permanent magnet slot and the fourth inner-layer permanent magnet slot satisfies: 0 < V4 - V2 < 30°; the angle V1 between the first outer-layer permanent magnet slot and the second outer-layer permanent magnet slot satisfies: 145° < V1 < 180°; the angle V3 between the third outer-layer permanent magnet slot and the fourth outer-layer permanent magnet slot satisfies: 0 < V4 - V3 < 30°; D2 is the distance from the outer end of the fourth inner-layer permanent magnet slot to the q-axis, and D1 and D2 satisfy: 2.3 < D1 / D2 < 6.3, and 0 < D2 < 2*gap, where gap is the air gap of the motor; D3 is the distance from the outer end of the first outer-layer permanent magnet slot to the q-axis, D4 is the distance from the outer end of the fourth outer-layer permanent magnet slot to the q-axis, and D3 and D4 satisfy: 2 < D3 / D1 < 5, 0 < D3 - D4 < 0.5*A1, where A1 is the length of the permanent magnet in the first outer-layer permanent magnet slot.

[0025] The first notch is located between the d-axis and the q-axis, and along the circumferential direction from the d-axis to the q-axis, the depth of the first notch gradually increases.

[0026] The second notch is located between the d-axis and the q-axis, and along the circumferential direction from the d-axis to the q-axis, the depth of the second notch gradually increases.

[0027] The width G1 and depth F1 of the first notch satisfy: 1 < F1 / G1 < 0.5*B1 / gap + 0.4; the width G2 and depth F2 of the second notch satisfy: 1 < F2 / G2 < 0.85*B1 / gap + 0.4; where, gap < G1 < 1.8*gap, 0 < G1 - G2 < 0.5*Gap + 0.2, B1 is the width of the permanent magnet in the fourth outer-layer permanent magnet slot, and gap is the air gap of the motor.

[0028] The present invention also provides a motor, including the above-mentioned motor rotor.

[0029] The present invention also provides a vehicle, including the above-mentioned motor.

[0030] Compared with the prior art, the present invention has the following advantages and positive effects:

[0031] 1. The outer end of the first permanent magnet slot in the motor rotor of the present invention is connected to the outer end of the fourth permanent magnet slot adjacent thereto to form a first band-shaped magnetic isolation slot, and the outer end of the second permanent magnet slot is connected to the outer end of the third permanent magnet slot to form a second band-shaped magnetic isolation slot, thereby forming a plurality of first band-shaped magnetic isolation slots and a plurality of second band-shaped magnetic isolation slots located inside the air gap between the rotor and the stator and staggered along the circumferential direction. Correspondingly, a band-shaped magnetic isolation bridge located outside the first band-shaped magnetic isolation slot and the second band-shaped magnetic isolation slot is formed on the rotor core; the plurality of first band-shaped magnetic isolation slots and the plurality of second band-shaped magnetic isolation slots staggered along the circumferential direction can play a role similar to that of an air gap. When the magnetic lines of force of the main magnetic flux pass through the q-axis, the band-shaped magnetic isolation slots and the band-shaped magnetic isolation bridge can effectively slow down the sudden change of magnetic resistance of the magnetic lines of force from the iron core to the air gap, thereby effectively reducing the risk of magnetic line distortion, reducing the harmonic distortion rate of the air gap magnetic field, thereby reducing the alternating frequency f of the magnetic field, and further reducing iron loss, thereby improving motor efficiency;

[0032] 2. Since the q-axis is the main path for the main magnetic flux to pass through, and since magnetic leakage is very likely to occur near the strip-shaped magnetic isolation bridge of the permanent magnet slot, local magnetic density saturation is likely to occur in the q-axis area at the outer circle of the rotor. The strip-shaped magnetic isolation bridge can effectively improve the uniformity of the magnetic field distribution, avoid excessive local magnetic flux density, and thus reduce the maximum magnetic flux density B. m , thereby reducing iron loss;

[0033] 3. The magnetic isolation bridge can effectively block the flow path of eddy current in the local area, thereby reducing eddy current loss and iron loss;

[0034] 4. In the motor rotor of the present invention, two first notches symmetrical about the d-axis are formed on the outer circle of the rotor core between the first permanent magnet slot and the second permanent magnet slot, and / or two second notches symmetrical about the d-axis are formed on the outer circle of the rotor core between the third permanent magnet slot and the fourth permanent magnet slot, which can effectively optimize the magnetic resistance of the magnetic isolation bridge of the permanent magnet slot, make the air gap magnetic field distribution more sinusoidal, thereby reducing the harmonic content of the air gap magnetic field, thereby reducing the alternating frequency f of the magnetic field, and further reducing the iron loss;

[0035] 5. The first notch and the second notch can also effectively block the flow path of eddy current in the local area, thereby reducing eddy current loss and iron loss; by modifying the first notch and the second notch, the air gap harmonic magnetic field can be effectively optimized, and the air gap magnetic field harmonic distortion rate can be reduced, thereby effectively suppressing the iron loss at high speed, thereby improving the motor efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0037] Figure 1 A schematic diagram of a motor rotor structure according to some embodiments of the present invention;

[0038] Figure 2 A schematic diagram of a partial structure of a motor rotor according to some embodiments of the present invention;

[0039] Figure 3 A schematic diagram of a partial structure of a rotor core according to some embodiments of the present invention;

[0040] Figure 4 A schematic diagram of a partial structure of a motor rotor in some further embodiments of the present invention;

[0041] Figure 5 Schematic diagram of the partial structure of the motor rotor in some embodiments of the present invention.

[0042] 100. Rotor body; 110. Rotor core; I. First permanent magnet slot group; 111. First permanent magnet slot; 111a. First inner permanent magnet slot; 111b. First outer permanent magnet slot; 112. Second permanent magnet slot; 112a. Second inner permanent magnet slot; 112b. Second outer permanent magnet slot; II. Second permanent magnet slot group; 113. Third permanent magnet slot; 113a. Third inner permanent magnet slot; 113b. Third outer permanent magnet slot; 114. Fourth permanent magnet slot; 114a. Fourth inner permanent magnet slot; 114b. Fourth outer permanent magnet slot; 115. First notch; 116. Second notch; 117. First belt-shaped magnetic isolation slot; 118. Second belt-shaped magnetic isolation slot; 119. Magnetic isolation bridge; III. Outer circle of rotor core; 120. Permanent magnet. DETAILED DESCRIPTION

[0043] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0045] The motor in the embodiment of the present invention comprises a coaxially arranged motor stator and a motor rotor, and a stator-rotor air gap, referred to as an air gap, is formed between the outer peripheral wall of the motor rotor and the inner peripheral wall of the motor stator.

[0046] Reference Figures 1 to 3 In some embodiments of the present invention, the motor rotor includes a rotor body 100 .

[0047] The rotor body 100 includes a rotor core 110 and permanent magnets 120 .

[0048] A plurality of first permanent magnet slot groups I and a plurality of second permanent magnet slot groups II are formed on the rotor core 110. The first permanent magnet slot groups I and the second permanent magnet slot groups II are alternately arranged along the circumferential direction of the rotor core 110, that is, they are arranged in sequence along the circumferential direction according to one first permanent magnet slot group I, one second permanent magnet slot group II, one first permanent magnet slot group I, one second permanent magnet slot group II, and so on. The first permanent magnet slot groups I at each location have the same structure and the same size parameters, and the second permanent magnet slot groups II at each location have the same structure and the same size parameters.

[0049] The first permanent magnet slot group I includes a first permanent magnet slot 111 and a second permanent magnet slot 112 that are symmetrical about the d-axis of the motor and arranged in a V shape, that is, the first permanent magnet slot 111 and the second permanent magnet slot 112 have the same structure and the same size parameters, and the cross-sections are both inclined straight strips, forming a V-shaped structure with an opening toward the outer peripheral wall of the rotor core 110. Similarly, the second permanent magnet slot group II includes a third permanent magnet slot 113 and a fourth permanent magnet slot 114 that are symmetrical about the d-axis of the motor and arranged in a V shape, that is, the third permanent magnet slot 113 and the fourth permanent magnet slot 114 have the same structure and the same size parameters, and the cross-sections are both inclined straight strips, forming a V-shaped structure with an opening toward the outer peripheral wall of the rotor core 110.

[0050] For any one of the first permanent magnet slot group I and the two second permanent magnet slot groups II adjacent to the first permanent magnet slot group I, the first permanent magnet slot 111 of the first permanent magnet slot group I is adjacent to the fourth permanent magnet slot 114 of one of the second permanent magnet slot groups II, and the outer end of the first permanent magnet slot 111 is connected to the outer end of the fourth permanent magnet slot 114 to form a first band-shaped magnetic isolation slot 117; the second permanent magnet slot 112 of the first permanent magnet slot group I is adjacent to the third permanent magnet slot 113 of another second permanent magnet slot group II, and the outer end of the second permanent magnet slot 112 is connected to the outer end of the third permanent magnet slot 113 to form a second band-shaped magnetic isolation slot 118. Accordingly, the rotor core 110 A strip-shaped magnetic isolation bridge 119 is formed on the outer side of the first strip-shaped magnetic isolation groove 117 and the second strip-shaped magnetic isolation groove 118; the first strip-shaped magnetic isolation groove 117 and the second strip-shaped magnetic isolation groove 118 respectively pass through the q-axis direction of the motor (that is, the first strip-shaped magnetic isolation groove 117 and the second strip-shaped magnetic isolation groove 118 respectively pass through their corresponding q-axes) and are located in the outer circle area of ​​the rotor core, that is, close to the outer circle III of the rotor core; two first notches 115 symmetrical about the d-axis are formed on the outer circle area of ​​the rotor core between the first permanent magnet slot 111 and the second permanent magnet slot 112, and two second notches 116 symmetrical about the d-axis are formed on the outer circle area of ​​the rotor core between the third permanent magnet slot 113 and the fourth permanent magnet slot 114.

[0051] The permanent magnets 120 are arranged in one-to-one correspondence with the first permanent magnet slot 111, the second permanent magnet slot 112, the third permanent magnet slot 113 and the fourth permanent magnet slot 114, and are respectively fixedly installed in the first permanent magnet slot 111, the second permanent magnet slot 112, the third permanent magnet slot 113 and the fourth permanent magnet slot 114. The permanent magnets 120 can be non-rare earth magnets and rare earth magnets, and the types of the permanent magnets 120 in each permanent magnet slot can be the same or different, and no specific limitation is made here.

[0052] The adjacent first permanent magnet slot group I and the permanent magnets 120 therein, and the second permanent magnet slot group II and the permanent magnets 120 therein constitute two adjacent poles of the motor, namely the N pole and the S pole, and multiple first permanent magnet slot groups I and the permanent magnets 120 therein, and multiple second permanent magnet slot groups II and the permanent magnets 120 therein constitute multiple pairs of poles of the motor.

[0053] Since the q-axis is the main path for the main magnetic flux to pass through, and since magnetic leakage is very likely to occur near the outer ends of the permanent magnet 120 slots, local magnetic flux saturation is likely to occur in the area around the outer circle of the rotor passing through the q-axis. The strip-shaped magnetic isolation slots can play a role similar to an air gap, effectively slowing down the fluctuation amplitude of the magnetic resistance change from the rotor core 110 to the air gap and the stator core to the air gap, reducing the harmonic distortion rate of the air gap magnetic field, improving the uniformity of the magnetic field distribution, avoiding excessive local magnetic flux density, and effectively blocking the flow path of eddy currents, thereby reducing the maximum magnetic induction intensity, thereby effectively suppressing the generation of iron losses at high speeds, and thus improving the efficiency of the motor.

[0054] Two first notches 115 symmetrical about the d-axis are formed on the outer circle area of ​​the rotor core between the first permanent magnet slot 111 and the second permanent magnet slot 112 in the motor rotor, and two second notches 116 symmetrical about the d-axis are formed on the outer circle area of ​​the rotor core between the third permanent magnet slot 113 and the fourth permanent magnet slot 114. By shaping the first notches 115 and the second notches 116, the air gap harmonic magnetic field can be effectively optimized and the harmonic distortion rate of the air gap magnetic field can be reduced, thereby effectively suppressing the generation of iron loss at high speed, thereby improving the motor efficiency.

[0055] In addition, the strip-shaped magnetic isolation grooves and gaps can effectively block the flow path of eddy currents in local areas, thereby reducing eddy current losses and iron losses. Under the above-mentioned combination method, the iron loss of the motor at high speed can be effectively reduced and the motor efficiency can be significantly improved.

[0056] In some embodiments of the present invention, the first permanent magnet slot group I and the second permanent magnet slot group II are asymmetric, forming an adjacent pole asymmetric magnetic circuit design. Since permanent magnet motors are usually controlled by sine waves, in order to better match the control, the rotor magnetic circuit should be designed as a sine wave as much as possible. The adjacent pole asymmetric magnetic circuit design can make the entire circumferential air gap magnetic field more sinusoidal. In addition to reducing torque pulsation, the sinusoidal wave magnetic field distribution can reduce high-order harmonics in the magnetic field, reduce the air gap magnetic field harmonic distortion rate, thereby reducing the alternating frequency of the magnetic field, and then reduce iron loss, which is further conducive to improving motor efficiency.

[0057] Accordingly, the first notch 115 and the second notch 116 are asymmetric and have different size parameters to match the corresponding magnetic circuit.

[0058] As for the permanent magnets 120 accommodated in each permanent magnet slot, their types can be the same or different. In order to reduce the cost of the motor, all permanent magnets 120 are of the same type. The size parameters of the permanent magnets 120 in the first inner layer permanent magnet slot 111a, the second inner layer permanent magnet slot 112a, the third inner layer permanent magnet slot 113a, and the fourth inner layer permanent magnet slot 114a are the same; the size parameters of the permanent magnets 120 in the first outer layer permanent magnet slot 111b, the second outer layer permanent magnet slot 112b, the third outer layer permanent magnet slot 113b, and the fourth outer layer permanent magnet slot 114b are the same.

[0059] In some embodiments of the present invention, Figures 1 to 3 As shown, the first permanent magnet slot 111 includes a first inner permanent magnet slot 111a and a first outer permanent magnet slot 111b located outside the first inner permanent magnet slot 111a, and the second permanent magnet slot 112 includes a second inner permanent magnet slot 112a and a second outer permanent magnet slot 112b located outside the second inner permanent magnet slot 112a; the first inner permanent magnet slot 111a and the second inner permanent magnet slot 112a are symmetrical about the d axis and arranged in a V shape, and the first outer permanent magnet slot 111b and the second outer permanent magnet slot 112b are symmetrical about the d axis and arranged in a V shape. That is, the first permanent magnet slot group I is an inner and outer double-layer structure, and the inner and outer permanent magnet slots 120 are arranged in a V shape, so that the first permanent magnet slot group I constitutes a double V-shaped permanent magnet slot group arrangement, so that the magnetic field distribution is more uniform, the edge effect is reduced, and the overall performance is enhanced.

[0060] Similarly, the third permanent magnet slot 113 includes a third inner permanent magnet slot 113a and a third outer permanent magnet slot 113b located outside the third inner permanent magnet slot 113a, and the fourth permanent magnet slot 114 includes a fourth inner permanent magnet slot 114a and a fourth outer permanent magnet slot 114b located outside the fourth inner permanent magnet slot 114a; the third inner permanent magnet slot 113a and the fourth inner permanent magnet slot 114a are symmetrical about the d axis and arranged in a V shape, and the third outer permanent magnet slot 113b and the fourth outer permanent magnet slot 114b are symmetrical about the d axis and arranged in a V shape. That is, the second permanent magnet slot group II is also an inner and outer double-layer structure, and the inner and outer permanent magnet slots are arranged in a V shape, so that the second permanent magnet slot group II constitutes a double V-shaped permanent magnet 120 slot group arrangement, so that the magnetic field distribution is more uniform, the edge effect is reduced, and the overall performance is enhanced.

[0061] Correspondingly, the outer end of the first inner permanent magnet slot 111a is connected with the outer end of the fourth inner permanent magnet slot 114a to form the above-mentioned first band-shaped magnetic isolation slot 117, and the outer end of the second inner permanent magnet slot 112a is connected with the outer end of the third inner permanent magnet slot 113a to form the above-mentioned second band-shaped magnetic isolation slot 118.

[0062] Among any two first notches 115 that are symmetrical about the d axis, one of the first notches 115 is located on the outer circular area of ​​the rotor core between the first inner permanent magnet slot 111a and the first outer permanent magnet slot 111b, and the other first notch 115 is located on the outer circular area of ​​the rotor core between the second inner permanent magnet slot 112a and the second outer permanent magnet slot 112b, so as to facilitate processing and improve space utilization.

[0063] Among any two second notches 116 that are axisymmetric about d, one of the second notches 116 is located on the outer circumferential region of the rotor core between the third inner permanent magnet slot 113a and the third outer permanent magnet slot 113b, and the other second notch 116 is located on the outer circumferential region of the rotor core between the fourth inner permanent magnet slot 114a and the fourth outer permanent magnet slot 114b, so as to facilitate processing and improve space utilization.

[0064] The first strip-shaped magnetic isolation slot 117, the second strip-shaped magnetic isolation slot 118, the first notch 115, and the second notch 116 need to select appropriate dimensions to avoid a significant increase in the magnetic resistance of the main magnetic flux path, which affects the performance of the motor. In addition, the mechanical properties of the rotor also need to be considered to avoid stress concentration.

[0065] In some embodiments of the present invention, the inner and outer diameters of the first strip-shaped magnetic isolation slot 117 satisfy: 0 < R1 - R2 < 2.4 * gap, and the inner and outer diameters of the second strip-shaped magnetic isolation slot 118 satisfy: 0 < R3 - R4 < 2.4 * gap; where R1 is the outer diameter of the first strip-shaped magnetic isolation slot 117, R2 is the inner diameter of the first strip-shaped magnetic isolation slot 117, R3 is the outer diameter of the second strip-shaped magnetic isolation slot 118, R4 is the inner diameter of the second strip-shaped magnetic isolation slot 118, gap is the air gap of the motor, and 0 < gap < 2.

[0066] In some embodiments of the present invention, the length A2 of the permanent magnet 120 in the first inner-layer permanent magnet slot 111a satisfies: 0.65*(π / P - 2*D1 / R0)*R0 < A2 < 0.85*(π / P - 2*D1 / R0)*R0, where D1 is the distance from the outer end of the first inner-layer permanent magnet slot 111a to the q-axis (i.e., the distance from one end of the first strip-shaped magnetic isolation slot 117 to the q-axis), P is the number of pole pairs of the motor, and R0 is the outer diameter of the rotor; the width B2 of the permanent magnet 120 in the fourth inner-layer permanent magnet slot 114a satisfies: 0.5*D1 < B2 < 1.5*D1; the angle V2 between the first inner-layer permanent magnet slot 111a and the second inner-layer permanent magnet slot 112a satisfies: 180° / P < V2 < 360° / P + 20°; the angle V4 between the third inner-layer permanent magnet slot 113a and the fourth inner-layer permanent magnet slot 114a satisfies: 0 < V4 - V2 < 30°; the angle V1 between the first outer-layer permanent magnet slot 111b and the second outer-layer permanent magnet slot 112b satisfies: 145° < V1 < 180°; the angle V3 between the third outer-layer permanent magnet slot 113b and the fourth outer-layer permanent magnet slot 114b satisfies: 0 < V4 - V3 < 30°; D2 is the distance from the outer end of the fourth inner-layer permanent magnet slot 114a to the q-axis (i.e., the distance from the other end of the first strip-shaped magnetic isolation slot 117 to the q-axis), and D1 and D2 satisfy: 2.3 < D1 / D2 < 6.3, and 0 < D2 < 2*gap, where gap is the air gap of the motor; D3 is the distance from the outer end of the first outer-layer permanent magnet slot 111b to the q-axis, D4 is the distance from the outer end of the fourth outer-layer permanent magnet slot 114b to the q-axis, and D3 and D4 satisfy: 2 < D3 / D1 < 5, 0 < D3 - D4 < 0.5*A1, where A1 is the length of the permanent magnet 120 in the first outer-layer permanent magnet slot 111b.

[0067] In some embodiments of the present invention, as Figure 2 and Figure 3 shown, the first notch 115 is located between the d-axis and the adjacent q-axis, and along the circumferential direction from the d-axis towards the q-axis, the depth of the first notch 115 gradually increases.

[0068] Similarly, the second notch 116 is located between the d-axis and the adjacent q-axis, and along the circumferential direction from the d-axis towards the q-axis, the depth of the second notch 116 gradually increases.

[0069] Through the above dimension design, the cross-sections of the first notch 115 and the second notch 116 are approximately axe-shaped, which can effectively optimize the magnetic resistance of the magnetic isolation bridge between the inner and outer layer permanent magnet slots, make the air-gap magnetic field distribution more sinusoidal, thereby reducing the harmonic content of the air-gap magnetic field, reducing the alternating frequency of the magnetic field, and further reducing the iron loss.

[0070] Furthermore, the width G1 and depth F1 of the first notch 115 satisfy: 1 < F1 / G1 < 0.5*B1 / gap + 0.4; the width G2 and depth F2 of the second notch 116 satisfy: 1 < F2 / G2 < 0.85*B1 / gap + 0.4. Wherein, gap < G1 < 1.8*gap, 0 < G1 - G2 < 0.5*Gap + 0.2, B1 is the width of the permanent magnet 120 in the fourth outer permanent magnet slot 114b, and gap is the motor air gap.

[0071] Referring to Figure 4 , in some further embodiments of the present invention, the number of the first permanent magnet slots 111 in each first permanent magnet slot group I is one, and the number of the second permanent magnet slots 112 is one; the number of the third permanent magnet slots 113 in each second permanent magnet slot group II is one, and the number of the fourth permanent magnet slots 114 is one. That is, the first permanent magnet slot group I is a single V-shaped structure, and the second permanent magnet slot group II is a single V-shaped structure.

[0072] Referring to Figure 5 , in some further embodiments of the present invention, only two first notches 115 symmetric about the d-axis are formed in the outer circumferential region of the rotor core between the first permanent magnet slot 111 and the second permanent magnet slot 112, and no second notch 116 is provided in the outer circumferential region of the rotor core between the third permanent magnet slot 113 and the fourth permanent magnet slot 114. Alternatively, no first notch 115 is provided in the outer circumferential region of the rotor core between the first permanent magnet slot 111 and the second permanent magnet slot 112, and only two second notches 116 symmetric about the d-axis are formed in the outer circumferential region of the rotor core between the third permanent magnet slot 113 and the fourth permanent magnet slot 114.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A motor rotor, characterized in that: The invention comprises a rotor body, wherein the rotor body comprises: A rotor core, wherein a plurality of first permanent magnet slot groups and a plurality of second permanent magnet slot groups are formed on the rotor core, wherein the first permanent magnet slot groups and the second permanent magnet slot groups are alternately arranged along the circumferential direction of the rotor core; the first permanent magnet slot group comprises a first permanent magnet slot and a second permanent magnet slot which are symmetrical about the d axis and arranged in a V shape, the second permanent magnet slot group comprises a third permanent magnet slot and a fourth permanent magnet slot which are symmetrical about the d axis and arranged in a V shape, the first permanent magnet slot is adjacent to the fourth permanent magnet slot, and the second permanent magnet slot is adjacent to the third permanent magnet slot; the first permanent magnet slot The outer end of the body slot is connected with the outer end of the fourth permanent magnet slot to form a first band-shaped magnetic isolation slot, the outer end of the second permanent magnet slot is connected with the outer end of the third permanent magnet slot to form a second band-shaped magnetic isolation slot, the first band-shaped magnetic isolation slot and the second band-shaped magnetic isolation slot respectively pass through the q-axis direction and are located in the outer circle area of ​​the rotor core; two first notches symmetrical about the d-axis are formed on the outer circle of the rotor core between the first permanent magnet slot and the second permanent magnet slot, and / or two second notches symmetrical about the d-axis are formed on the outer circle of the rotor core between the third permanent magnet slot and the fourth permanent magnet slot; Permanent magnets are respectively installed in the first permanent magnet slot, the second permanent magnet slot, the third permanent magnet slot and the fourth permanent magnet slot.

2. The motor rotor according to claim 1, characterized in that: The first permanent magnet slot group and the second permanent magnet slot group are asymmetric, and the first notch and the second notch are asymmetric.

3. The motor rotor according to claim 2, characterized in that: The number of the first permanent magnet slots in each of the first permanent magnet slot groups is one, and the number of the second permanent magnet slots is one; The number of the third permanent magnet slots in each of the second permanent magnet slot groups is one, and the number of the fourth permanent magnet slots is one.

4. The motor rotor according to claim 2, characterized in that: The first permanent magnet slot includes a first inner permanent magnet slot and a first outer permanent magnet slot located outside the first inner permanent magnet slot, and the second permanent magnet slot includes a second inner permanent magnet slot and a second outer permanent magnet slot located outside the second inner permanent magnet slot; the first inner permanent magnet slot and the second inner permanent magnet slot are symmetrical about the d axis and arranged in a V shape, and the first outer permanent magnet slot and the second outer permanent magnet slot are symmetrical about the d axis and arranged in a V shape; The third permanent magnet slot includes a third inner permanent magnet slot and a third outer permanent magnet slot located outside the third inner permanent magnet slot, and the fourth permanent magnet slot includes a fourth inner permanent magnet slot and a fourth outer permanent magnet slot located outside the fourth inner permanent magnet slot; the third inner permanent magnet slot and the fourth inner permanent magnet slot are symmetrical about the d axis and arranged in a V shape, and the third outer permanent magnet slot and the fourth outer permanent magnet slot are symmetrical about the d axis and arranged in a V shape; The outer ends of the first inner-layer permanent magnet slots communicate with the outer ends of the fourth inner-layer permanent magnet slots to form the first strip-shaped magnetic isolation slot, and the outer ends of the second inner-layer permanent magnet slots communicate with the outer ends of the third inner-layer permanent magnet slots to form the second strip-shaped magnetic isolation slot; Among the two first notches, one is located on the outer circumference of the rotor core between the first inner-layer permanent magnet slot and the first outer-layer permanent magnet slot, and the other is located on the outer circumference of the rotor core between the second inner-layer permanent magnet slot and the second outer-layer permanent magnet slot; Among the two second notches, one is located on the outer circumference of the rotor core between the third inner-layer permanent magnet slot and the third outer-layer permanent magnet slot, and the other is located on the outer circumference of the rotor core between the fourth inner-layer permanent magnet slot and the fourth outer-layer permanent magnet slot.

5. The motor rotor according to claim 1, wherein The inner and outer diameters of the first strip-shaped magnetic isolation slot satisfy: 0 < R1 - R2 < 2.4 * gap, and the inner and outer diameters of the second strip-shaped magnetic isolation slot satisfy: 0 < R3 - R4 < 2.4 * gap; Wherein, R1 is the outer diameter of the first strip-shaped magnetic isolation slot, R2 is the inner diameter of the first strip-shaped magnetic isolation slot, R3 is the outer diameter of the second strip-shaped magnetic isolation slot, R4 is the inner diameter of the second strip-shaped magnetic isolation slot, gap is the motor air gap, and 0 < gap < 2.

6. The motor rotor according to claim 4, wherein The length A2 of the permanent magnet in the first inner-layer permanent magnet slot satisfies: 0.65 * (π / P - 2 * D1 / R0) * R0 < A2 < 0.85 * (π / P - 2 * D1 / R0) * R0, where D1 is the distance from the outer end of the first inner-layer permanent magnet slot to the q-axis, P is the number of pole pairs of the motor, and R0 is the outer diameter of the rotor; the width B2 of the permanent magnet in the fourth inner-layer permanent magnet slot satisfies: 0.5 * D1 < B2 < 1.5 * D1; the angle V2 between the first inner-layer permanent magnet slot and the second inner-layer permanent magnet slot satisfies: 180° / P < V2 < 360° / P + 20°; the angle V4 between the third inner-layer permanent magnet slot and the fourth inner-layer permanent magnet slot satisfies: 0 < V4 - V2 < 30°; the angle V1 between the first outer-layer permanent magnet slot and the second outer-layer permanent magnet slot satisfies: 145° < V1 < 180°; the angle V3 between the third outer-layer permanent magnet slot and the fourth outer-layer permanent magnet slot satisfies: 0 < V4 - V3 < 30°; D2 is the distance from the outer end of the fourth inner-layer permanent magnet slot to the q-axis, and D1 and D2 satisfy: 2.3 < D1 / D2 < 6.3, and 0 < D2 < 2 * gap, where gap is the motor air gap; D3 is the distance from the outer end of the first outer-layer permanent magnet slot to the q-axis, D4 is the distance from the outer end of the fourth outer-layer permanent magnet slot to the q-axis, and D3 and D4 satisfy: 2 < D3 / D1 < 5, 0 < D3 - D4 < 0.5 * A1, and A1 is the length of the permanent magnet in the first outer-layer permanent magnet slot.

7. The motor rotor according to claim 4, wherein The first notch is located between the d-axis and the q-axis, and along the circumferential direction from the d-axis to the q-axis, the depth of the first notch gradually increases; The second notch is located between the d-axis and the q-axis, and the depth of the second notch gradually increases from the d-axis along the circumference towards the q-axis.

8. The motor rotor according to claim 7, wherein The width G1 and the depth F1 of the first notch satisfy: 1 < F1 / G1 < 0.5*B1 / gap + 0.4; the width G2 and the depth F2 of the second notch satisfy: 1 < F2 / G2 < 0.85*B1 / gap + 0.4; wherein, gap < G1 < 1.8*gap, 0 < G1 - G2 < 0.5*Gap + 0.2, and B1 is the width of the permanent magnet in the fourth outer permanent magnet slot, and gap is the motor air gap.

9. A motor, characterized in that: Comprising the motor rotor according to any one of claims 1-8.

10. A vehicle, characterized in that: Comprising the motor according to claim 9.

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