A permanent magnet synchronous motor with unequal magnetic pole thickness

Abstract

The present application relates to a permanent magnet synchronous motor with unequal thickness magnetic poles, the synchronous motor comprising: a stator core, an unequal thickness permanent magnet assembly, a rotor core and an armature winding assembly, the thickness of the permanent magnet of the unequal thickness permanent magnet assembly is linearly or step-thickened, wherein, with the rotation direction of the motor when it is in electric operation as the forward direction, the thickness of the front end of the permanent magnet is less than the thickness of the rear end; the permanent magnet of the unequal thickness permanent magnet assembly is installed on the rotor core, and the salient pole structure of the rotor core matched with the permanent magnet of the unequal thickness permanent magnet assembly is located at the front end of the permanent magnet of the unequal thickness permanent magnet assembly; the rotor core with the unequal thickness permanent magnet assembly installed is sleeved inside the stator core, and the rotor core and the stator core are coaxially distributed; the armature winding of the armature winding assembly is embedded on the stator core. The rear end of the permanent magnet is thickened, so that the permanent magnet has higher anti-demagnetization performance, thereby improving the output torque capacity and motor efficiency under heavy load conditions of the motor.

Description

Technical Field

[0001] The present application relates to the technical field of permanent magnet motors, and particularly to an unequal-thickness pole type permanent magnet synchronous motor. Background Art

[0002] Since the permanent magnet synchronous motor uses permanent magnets instead of excitation windings, eliminating components such as brushes and commutators, it improves the operating reliability of the motor while eliminating excitation losses, thereby enhancing the efficiency and power density of the motor. In recent years, high-performance permanent magnet motors have been widely used in fields such as automobiles, aerospace, and household appliances. In many applications, the motor is only required to operate in one direction or rotate in a specific direction for most of the time.

[0003] The permanent magnet synchronous motor is also composed of components such as a stator, a rotor, a housing, and end covers. The stator is basically the same as that of an asynchronous induction motor, and generally adopts a laminated design to reduce the iron loss of the iron core. The rotor core can be made solid or laminated.

[0004] In related technologies, the rotor of a permanent magnet synchronous motor can adopt a surface-mounted permanent magnet structure. The permanent magnets are usually in the shape of tiles and are located on the surface of the rotor. This structure has advantages such as simple structure and low manufacturing cost. At the same time, the air-gap magnetic density waveform is also close to a sine wave, which can significantly improve the transmission performance of the entire system. However, the difference between the direct-axis and quadrature-axis inductances of this structure is relatively small, the saliency ratio of the motor is low, and the reluctance torque component in the output electromagnetic torque can be ignored, resulting in a lower output torque capacity and motor efficiency under heavy load conditions of the motor. Summary of the Invention

[0005] Based on this, it is necessary to provide an unequal-thickness pole type permanent magnet synchronous motor that can improve the output torque capacity and motor efficiency under heavy load conditions of the motor for the above technical problems.

[0006] An unequal-thickness pole type permanent magnet synchronous motor, the synchronous motor includes: a stator core, an unequal-thickness permanent magnet assembly, a rotor core, and an armature winding assembly; the thickness of the permanent magnets of the unequal-thickness permanent magnet assembly increases linearly or stepwise, wherein, taking the rotation direction of the motor during electric operation as the forward direction, the thickness of the front end of the permanent magnet is less than the thickness of the rear end; the permanent magnets of the unequal-thickness permanent magnet assembly are installed on the rotor core, and the salient pole structure of the rotor core that cooperates with the permanent magnets of the unequal-thickness permanent magnet assembly is located at the front end of the permanent magnets of the unequal-thickness permanent magnet assembly; the rotor core installed with the unequal-thickness permanent magnet assembly is sleeved inside the stator core, and the rotor core and the stator core are coaxially distributed; the armature windings of the armature winding assembly are embedded in the stator core.

[0007] In one embodiment, the permanent magnets of the unequal-thickness permanent magnet assembly are attached to the outer surface of the rotor core.

[0008] In one embodiment, the armature winding is a double-layer distributed winding, a single-layer distributed winding or a concentrated winding.

[0009] In one embodiment, the stator core is made by laminating silicon steel sheets or made of soft magnetic material.

[0010] In one embodiment, the rotor core is made by laminating silicon steel sheets or made of soft magnetic material.

[0011] In one embodiment, the permanent magnets of the unequal-thickness permanent magnet assembly are magnetized in parallel or radially.

[0012] An unequal-thickness pole-type permanent magnet synchronous motor, the synchronous motor includes: a rotor core, an unequal-thickness permanent magnet assembly, a stator core and an armature winding assembly; the thickness of the permanent magnets of the unequal-thickness permanent magnet assembly increases linearly or stepwise, wherein, with the rotation direction of the motor during electric operation as the forward direction, the thickness of the front end of the permanent magnet is less than that of the rear end; the permanent magnets of the unequal-thickness permanent magnet assembly are installed on the stator core, and the salient pole structure of the stator core cooperating with the permanent magnets of the unequal-thickness permanent magnet assembly is located at the front end of the permanent magnets of the unequal-thickness permanent magnet assembly; the stator core on which the permanent magnets of the unequal-thickness permanent magnet assembly are installed is sleeved inside the rotor core, and the stator core and the rotor core are coaxially distributed; the armature winding of the armature winding assembly is embedded on the rotor core.

[0013] In one embodiment, the permanent magnets of the unequal-thickness permanent magnet assembly are attached to the outer surface of the stator core.

[0014] In one embodiment, the armature winding is a double-layer distributed winding, a single-layer distributed winding or a concentrated winding.

[0015] In one embodiment, the permanent magnets of the unequal-thickness permanent magnet assembly are magnetized in parallel or radially.

[0016] The above-mentioned permanent magnet synchronous motor with unequal-thickness magnetic poles includes: a stator core, an unequal-thickness permanent magnet assembly, a rotor core, and an armature winding assembly. The thickness of the permanent magnets in the unequal-thickness permanent magnet assembly increases linearly or stepwise. Among them, taking the rotation direction of the motor during electric operation as the forward direction, the thickness of the front end of the permanent magnet is less than that of the rear end. The permanent magnets of the unequal-thickness permanent magnet assembly are installed on the rotor core, and the salient pole structure of the rotor core that cooperates with the permanent magnets of the unequal-thickness permanent magnet assembly is located at the front end of the permanent magnets of the unequal-thickness permanent magnet assembly. The rotor core installed with the unequal-thickness permanent magnet assembly is sleeved inside the stator core, and the rotor core and the stator core are coaxially distributed. The armature windings of the armature winding assembly are embedded in the stator core. Thus, the saliency of the rotor core is enhanced. The obvious salient pole rotor core structure makes the direct and quadrature axis inductances of the motor have a large difference. This structure of the motor can utilize the reluctance torque and significantly improve the output electromagnetic torque of the motor while maintaining the same amount of permanent magnets used. Especially under the heavy load condition of the motor, the motor has a higher output torque. And the thickening of the rear end of the permanent magnet makes the permanent magnet have higher demagnetization resistance performance, thereby improving the output torque ability and motor efficiency under the heavy load condition of the motor. Description of the Drawings

[0017] Figure 1 It is a schematic axial cross-sectional structure diagram of a permanent magnet synchronous motor with unequal-thickness magnetic poles in an embodiment;

[0018] Figure 2 It is a schematic diagram of the axial cross-sectional structure of the rotor and the side-sector permanent magnets, the magnetization direction of the permanent magnets, and the rotation direction of the motor in an embodiment;

[0019] Figure 3 It is a schematic diagram of the axial cross-sectional structure of the rotor and the side-parallel permanent magnets, the magnetization direction of the permanent magnets, and the rotation direction of the motor in an embodiment;

[0020] Figure 4 It is a schematic axial cross-sectional structure diagram of a permanent magnet synchronous motor with unequal-thickness magnetic poles in another embodiment;

[0021] Figure 5 It is a waveform diagram of the circumferential position distribution of the radial magnetic density in the air gap in an embodiment;

[0022] Figure 6 It is a waveform diagram of the three-phase magnetic flux of the motor varying with the rotor angle in an embodiment;

[0023] Figure 7 It is a waveform diagram of the output torque of the motor in an embodiment;

[0024] Figure 8 It is a waveform diagram of the reluctance torque of the motor in an embodiment;

[0025] Figure 9Waveform diagram of the permanent magnet torque of the motor in an embodiment;

[0026] Figure 10 Schematic diagram of the comparison of the maximum output torque of different amplitude currents in an embodiment;

[0027] Figure 11 Schematic diagram of the comparison of the demagnetization situation of the permanent magnet in an embodiment. Detailed implementation manners

[0028] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] In an embodiment, as Figure 1 shown, a permanent magnet synchronous motor with unequal-thickness magnetic poles is provided. The synchronous motor includes: a stator core 1, an unequal-thickness permanent magnet assembly, a rotor core 3, and an armature winding assembly; the thickness of the permanent magnet 2 of the unequal-thickness permanent magnet assembly increases linearly or stepwise. Wherein, taking the rotation direction of the motor during electric operation as the forward direction, the thickness of the front end of the permanent magnet 2 is less than the thickness of the rear end; the permanent magnet 2 of the unequal-thickness permanent magnet assembly is installed on the rotor core 3, and the salient pole structure of the rotor core 3 cooperating with the permanent magnet 2 of the unequal-thickness permanent magnet assembly is located at the front end of the permanent magnet 2 of the unequal-thickness permanent magnet assembly; the rotor core 3 installed with the unequal-thickness permanent magnet assembly is sleeved inside the stator core 1, and the rotor core 3 and the stator core 1 are coaxially distributed; the armature winding 4 of the armature winding assembly is embedded on the stator core 1.

[0030] Among them, the unequal-thickness permanent magnet assembly may include p pairs of permanent magnet poles. Each pair of permanent magnet poles includes two permanent magnets 2 with different magnetic poles. The 2p permanent magnets are evenly distributed on the outer surface of the rotor core 3, and the magnetic poles of two adjacent permanent magnets 2 are different. The number of pairs of permanent magnet poles can be set according to the actual situation.

[0031] It should be understood that if the motor operates in the electric mode, along the rotation direction, the front end of the permanent magnet 2 is thinner and the rear end of the permanent magnet 2 is thickened. The amount of permanent magnet used in the surface-mounted permanent magnet synchronous motor with equal-thickness permanent magnets is basically the same. The permanent magnet synchronous motor with unequal-thickness magnetic poles of the present application will not increase the amount of permanent magnet used.

[0032] It should be understood that if the motor operates in the power generation mode, along the rotation direction, correspondingly, the front end of the permanent magnet 2 is thickened and the rear end of the permanent magnet 2 is thinner.

[0033] Among them, 2p permanent magnet slots are evenly distributed on the outer surface of the rotor core 3. Wherein, p is the number of pairs of permanent magnet poles of the motor. The permanent magnet 2 is placed in a surface-mounted manner and can be magnetized either parallelly or radially.

[0034] Among them, the permanent magnet 2 can adopt a sector shape, such as Figure 2 shown. Taking the side where the permanent magnet 2 is attached to the outer surface of the rotor core 3 as the first side, the side opposite to the first side as the second side, and the two sides intersecting with the first side as the third side and the fourth side respectively. The second sides of each permanent magnet 2 of the unequal-thickness permanent magnet assembly are connected to form a circle, and the center of the circle is the center of the rotor core 3. When the permanent magnet 2 adopts a sector shape, the sector formed by the two radii at both ends of the second side, the third side coincides with one of the radii of the sector, and the fourth side coincides with the other radius of the sector.

[0035] Among them, the permanent magnet 2 can adopt a shape with parallel sides, such as Figure 3 shown. Taking the side where the permanent magnet 2 is attached to the outer surface of the rotor core 3 as the first side, the side opposite to the first side as the second side, and the two sides intersecting with the first side as the third side and the fourth side respectively. The second sides of each permanent magnet 2 of the unequal-thickness permanent magnet assembly are connected to form a circle, and the center of the circle is the center of the rotor core 3. When the permanent magnet 2 adopts a shape with parallel sides, the third side and the fourth side are parallel.

[0036] In a possible embodiment, the permanent magnets 2 of the unequal-thickness permanent magnet assembly are attached to the outer surface of the rotor core 3.

[0037] It should be understood that the permanent magnets 2 of the unequal-thickness permanent magnet assembly attached to the outer surface of the rotor core 3 constitute surface-mounted unequal-thickness permanent magnets 2, and the surface-mounted unequal-thickness permanent magnets 2 can be magnetized either in parallel or radially.

[0038] Among them, the pole arc coefficient of the surface-mounted unequal-thickness permanent magnet is Among them, θ m is the central angle occupied by the arc length of the surface-mounted permanent magnet, in radians, p is the number of pole pairs, and α p is the pole arc coefficient.

[0039] It should be understood that the pole arc coefficient can be adjusted by adjusting the central angle θ m occupied by the arc length of the surface-mounted permanent magnet, and the magnitudes of the permanent magnet torque and the reluctance torque can be changed, so that the two are superimposed to output the maximum electromagnetic torque.

[0040] In a possible embodiment, the unequal-thickness permanent magnet assembly is magnetized either in parallel or radially.

[0041] In a possible embodiment, there are Z tooth grooves distributed on the stator core 1, the groove type is a pear-shaped groove, and the armature winding 4 of the armature winding assembly is embedded inside.

[0042] Among them, the number of tooth grooves can be set according to the actual situation.

[0043] In a possible embodiment, the armature winding 4 is a double-layer distributed winding, a single-layer distributed winding or a concentrated winding.

[0044] In a possible embodiment, the armature winding 4 can adopt a three-phase stator winding.

[0045] In a possible embodiment, the armature winding 4 can also adopt a fractional-slot stator winding to reduce torque ripple.

[0046] In a possible embodiment, the stator core 1 is made of laminated silicon steel sheets or soft magnetic materials.

[0047] In a possible embodiment, the rotor core 3 is made of laminated silicon steel sheets or soft magnetic materials.

[0048] It should be understood that for a permanent magnet synchronous motor using permanent magnets with unequal thicknesses, there is a large difference in the armature direct and quadrature axis inductances of the motor, enabling the utilization of the reluctance torque of the motor, thereby achieving the effect of improving the output electromagnetic torque of the motor; at the same time, thickening the rear end of the permanent magnets of the motor under the premise of controlling the permanent magnet usage is beneficial to weakening the demagnetization effect of the armature reaction on the permanent magnets under heavy load conditions, thereby further improving the overload operation ability of the motor.

[0049] The above-mentioned unequal-thickness pole type permanent magnet synchronous motor, through a synchronous motor including: a stator core 1, an unequal-thickness permanent magnet assembly, a rotor core 3 and an armature winding assembly, the thickness of the permanent magnet 2 of the unequal-thickness permanent magnet assembly increases linearly or stepwise, wherein, taking the rotation direction of the motor during electric operation as the forward direction, the thickness of the front end of the permanent magnet 2 is less than the thickness of the rear end; the permanent magnet 2 of the unequal-thickness permanent magnet assembly is installed on the rotor core 3, and the salient pole structure of the rotor core 3 cooperating with the permanent magnet 2 of the unequal-thickness permanent magnet assembly is located at the front end of the permanent magnet 2 of the unequal-thickness permanent magnet assembly; the rotor core 3 installed with the unequal-thickness permanent magnet assembly is sleeved inside the stator core 1, and the rotor core 3 and the stator core 1 are coaxially distributed; the armature winding 4 of the armature winding assembly is embedded on the stator core 1. Thus, the saliency of the rotor core is enhanced, and the obvious salient pole rotor core structure causes a large difference in the armature direct and quadrature axis inductances of the motor. This structure of the motor can utilize the reluctance torque, and under the condition of maintaining the same permanent magnet usage, significantly improve the output electromagnetic torque of the motor, especially when the motor is under heavy load, the motor has a higher output torque, and the rear end of the permanent magnet is thickened, making the permanent magnet have higher demagnetization resistance performance, thereby improving the output torque ability and motor efficiency under heavy load conditions of the motor.

[0050] In an embodiment, as Figure 4As shown in the figure, an unequal-thickness pole-type permanent magnet synchronous motor is provided. The synchronous motor includes: a rotor core 11, an unequal-thickness permanent magnet assembly, a stator core 13, and an armature winding assembly; the thickness of the permanent magnet 12 of the unequal-thickness permanent magnet assembly increases linearly or stepwise. Wherein, taking the rotation direction of the motor during electric operation as the forward direction, the thickness of the front end of the permanent magnet 12 is less than that of the rear end; the permanent magnet 12 of the unequal-thickness permanent magnet assembly is installed on the stator core 13, and the salient pole structure of the stator core 13 cooperating with the permanent magnet 12 of the unequal-thickness permanent magnet assembly is located at the front end of the permanent magnet 12 of the unequal-thickness permanent magnet assembly; the stator core 13 installed with the permanent magnet 12 of the unequal-thickness permanent magnet assembly is sleeved inside the rotor core 11, and the stator core 13 and the rotor core 11 are coaxially distributed; the armature winding 14 of the armature winding assembly is embedded on the rotor core 11.

[0051] Among them, the unequal-thickness permanent magnet assembly may include p pairs of permanent magnet poles. Each pair of permanent magnet poles includes two permanent magnets 12 with different magnetic poles. The 2p permanent magnets are evenly distributed on the outer surface of the stator core 13, and the magnetic poles of two adjacent permanent magnets 12 are different. The number of pairs of permanent magnet poles can be set according to actual situations.

[0052] It should be understood that if the motor operates in the electric mode, along the rotation direction, the front end of the permanent magnet 12 is thinner, and the rear end of the permanent magnet 12 is thickened. The amount of permanent magnets used in the unequal-thickness pole-type permanent magnet synchronous motor of the present application is basically the same as that of the surface-mounted permanent magnet synchronous motor with equal-thickness conventional permanent magnets, and the amount of permanent magnets used in the present application will not increase.

[0053] It should be understood that if the motor operates in the power generation mode, along the rotation direction, correspondingly, the front end of the permanent magnet 12 is thickened, and the rear end of the permanent magnet 12 is thinner.

[0054] Among them, 2p permanent magnet slots are evenly distributed on the outer surface of the stator core 13. Wherein, p is the number of pairs of permanent magnet poles of the motor. The permanent magnet 12 is placed in a surface-mounted manner and can be magnetized either parallelly or radially.

[0055] Among them, the permanent magnet 12 can adopt a fan shape. Taking the side where the permanent magnet 12 is attached to the outer surface of the stator core 13 as the first side, the side opposite to the first side as the second side, and the two sides intersecting with the first side as the third side and the fourth side respectively. The second sides of each permanent magnet 12 of the unequal-thickness permanent magnet assembly are connected to form a circle, and the center of the circle is the center of the stator core 13. When the permanent magnet 12 adopts a fan shape, the sector formed by the two radii at both ends of the second side, the third side coincides with one of the radii of the sector, and the fourth side coincides with the other radius of the sector.

[0056] Among them, the permanent magnet 12 can adopt a side-parallel shape. Taking the side of the permanent magnet 12 attached to the outer surface of the stator core 13 as the first side, the side opposite to the first side as the second side, and the two sides intersecting with the first side as the third side and the fourth side respectively. The second sides of each permanent magnet 12 of the unequal-thickness permanent magnet assembly are connected to form a circle, and the center of the circle is the center of the stator core 13. When the permanent magnet 12 adopts a side-parallel shape, the third side and the fourth side are parallel.

[0057] In a possible embodiment, the permanent magnets 12 of the unequal-thickness permanent magnet assembly are attached to the outer surface of the stator core 13.

[0058] It should be understood that the permanent magnets 12 of the unequal-thickness permanent magnet assembly attached to the outer surface of the stator core 13 constitute surface-mounted unequal-thickness permanent magnets 12, and the surface-mounted unequal-thickness permanent magnets 12 can be magnetized either parallelly or radially.

[0059] Among them, the pole arc coefficient of the surface-mounted unequal-thickness permanent magnet is Among them, θ m is the central angle occupied by the arc length of the surface-mounted permanent magnet, in radians, p is the number of pole pairs, and α p is the pole arc coefficient.

[0060] It should be understood that the pole arc coefficient can be adjusted by adjusting the central angle θ m occupied by the arc length of the surface-mounted permanent magnet, so as to change the magnitudes of the permanent magnet torque and the reluctance torque, so that the two are superimposed to output the maximum electromagnetic torque.

[0061] In a possible embodiment, the unequal-thickness permanent magnet assembly is magnetized either parallelly or radially.

[0062] In a possible embodiment, Z tooth grooves are distributed on the rotor core 11, the groove type is a pear-shaped groove, and the armature winding 14 of the armature winding assembly is embedded inside.

[0063] Among them, the number of tooth grooves can be set according to actual situations.

[0064] In a possible embodiment, the armature winding 14 is a double-layer distributed winding, a single-layer distributed winding or a concentrated winding.

[0065] In a possible embodiment, the armature winding 14 can adopt a three-phase stator winding.

[0066] In a possible embodiment, the armature winding 14 can also adopt a fractional-slot stator winding to reduce torque ripple.

[0067] In a possible embodiment, the rotor core 11 is made of laminated silicon steel sheets or soft magnetic materials.

[0068] In a possible embodiment, the stator core 13 is formed by laminating silicon steel sheets or made of soft magnetic material.

[0069] For the above unequal-thickness pole-type permanent magnet synchronous motor, the motor includes a rotor core 11, an unequal-thickness permanent magnet assembly, a stator core 13, and an armature winding assembly. The thickness of the permanent magnet 12 of the unequal-thickness permanent magnet assembly increases linearly or stepwise. Among them, taking the rotation direction of the motor during electric operation as the forward direction, the thickness of the front end of the permanent magnet 12 is less than that of the rear end. The permanent magnet 12 of the unequal-thickness permanent magnet assembly is installed on the stator core 13. The salient pole structure of the stator core 13 cooperating with the permanent magnet 12 of the unequal-thickness permanent magnet assembly is located at the front end of the permanent magnet 12 of the unequal-thickness permanent magnet assembly. The stator core 13 on which the permanent magnet 12 of the unequal-thickness permanent magnet assembly is installed is sleeved inside the rotor core 11. The stator core 13 and the rotor core 11 are coaxially distributed. The armature winding 14 of the armature winding assembly is embedded on the rotor core 11. Thus, the rotor core structure with obvious salient poles makes the direct-axis and quadrature-axis inductances of the motor have a large difference. This structure of the motor can utilize reluctance torque and significantly improve the output electromagnetic torque of the motor while maintaining the same amount of permanent magnet usage. Especially under the heavy-load condition of the motor, the motor has a higher output torque. And the rear end of the permanent magnet is thickened, making the permanent magnet have higher demagnetization resistance performance, thereby improving the output torque capacity and motor efficiency under the heavy-load condition of the motor.

[0070] In one embodiment, taking the unequal-thickness pole-type permanent magnet synchronous motor with 4 pairs of permanent magnet poles as an example, and taking 8 surface-mounted unequal-thickness permanent magnets 2 of this unequal-thickness pole-type permanent magnet synchronous motor as an example, as Figures 1 - 3 shown, along the rotation direction of the motor during electric operation, the thickness of the front end of the permanent magnet is 2.5 mm and increases linearly to 6.5 mm at the rear end of the permanent magnet. Among them, n is the rotational speed of the motor, operating in the electric mode, and the rotation direction is counterclockwise.

[0071] Simulating the unequal-thickness pole-type permanent magnet synchronous motor with 4 pairs of permanent magnet poles, the waveform diagram of the radial magnetic density distribution along the circumferential position in the air gap when the motor is under heavy load is as Figure 5 shown. It can be found that the air-gap magnetic density is approximately a sine waveform. Correspondingly, the waveform diagram of the three-phase magnetic flux of the motor varying with the rotor angle is as Figure 6 shown. Using the frozen permeability, the waveform diagrams of the motor output torque, reluctance torque, and permanent magnet torque are as Figures 7 - 9 shown. Compared with the traditional surface-mounted permanent magnet synchronous motor, the reluctance torque is effectively utilized.

[0072] The schematic diagram of comparing the maximum output torque of the unequal-thickness pole-type permanent magnet synchronous motor of the embodiment of the present application with the traditional surface-mounted permanent magnet motor when passing different amplitude currents under the premise of the same volume and the same amount of permanent magnet usage is as Figure 10As shown, it can be found that the output torque of the non-uniform thickness pole type permanent magnet synchronous motor of the embodiment of the present application is higher than that of the traditional surface-mounted permanent magnet synchronous motor, and in the case of heavy load, the torque improvement effect is more obvious.

[0073] The schematic diagram of the comparison of the demagnetization of the permanent magnet of the non-uniform thickness pole type permanent magnet synchronous motor of the embodiment of the present application and the traditional surface-mounted permanent magnet motor under heavy load conditions is as Figure 11 shown. It can be found that partial demagnetization will occur at the rear end of the permanent magnet of the traditional surface-mounted permanent magnet motor during heavy load, while the non-uniform thickness pole type permanent magnet synchronous motor of the embodiment of the present application has a higher anti-demagnetization ability due to the thickening of the rear end of the permanent magnet.

[0074] If the non-uniform thickness pole type permanent magnet synchronous motor of the embodiment of the present application is driven by a prime mover, it can perform power generation work. The non-uniform thickness pole type permanent magnet synchronous motor of the embodiment of the present application should rotate in the clockwise direction. Under the same conditions, the non-uniform thickness pole type permanent magnet synchronous motor of the embodiment of the present application will output a larger electric power.

[0075] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0076] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A permanent magnet synchronous motor with unequal thickness magnetic poles, characterized in that: The synchronous motor comprises: a stator core (1), a permanent magnet assembly of unequal thickness, a rotor core (3) and an armature winding assembly; The thickness of the permanent magnet (2) of the unequal thickness permanent magnet assembly increases linearly or in steps, wherein, taking the rotation direction of the motor when it is in electric operation as the forward direction, the thickness of the front end of the permanent magnet (2) is smaller than the thickness of the rear end; The permanent magnet (2) of the unequal thickness permanent magnet assembly is mounted on the rotor core (3), and the salient pole position of the rotor core (3) that cooperates with the permanent magnet (2) of the unequal thickness permanent magnet assembly is located at the front end of the permanent magnet (2) of the unequal thickness permanent magnet assembly; The rotor core (3) on which the unequal thickness permanent magnet assembly is mounted is sleeved inside the stator core (1), and the rotor core (3) and the stator core (1) are coaxially distributed; The armature winding (4) of the armature winding assembly is embedded in the stator core (1).

2. The synchronous motor according to claim 1, characterized in that: The permanent magnets (2) of the unequal thickness permanent magnet assembly are attached to the outer surface of the rotor core (3).

3. The synchronous motor according to claim 1, characterized in that: The armature winding (4) is a double-layer distributed winding, a single-layer distributed winding or a concentrated winding.

4. The synchronous motor according to claim 1, characterized in that: The stator core (1) is made of laminated silicon steel sheets or soft magnetic material.

5. The synchronous motor according to claim 1, characterized in that: The rotor core (3) is made of laminated silicon steel sheets or soft magnetic material.

6. The synchronous motor according to claim 1, characterized in that: The permanent magnets (2) of the unequal thickness permanent magnet assembly are magnetized in parallel or in radial direction.

7. A permanent magnet synchronous motor with unequal thickness magnetic poles, characterized in that: The synchronous motor comprises: a rotor core (11), a permanent magnet assembly of unequal thickness, a stator core (13) and an armature winding assembly; The thickness of the permanent magnet (12) of the unequal thickness permanent magnet assembly increases linearly or in steps, wherein, taking the rotation direction of the motor when it is in electric operation as the forward direction, the thickness of the front end of the permanent magnet (12) is smaller than the thickness of the rear end; The permanent magnet (12) of the unequal thickness permanent magnet assembly is mounted on the stator core (13), and the salient pole structure of the stator core (13) matched with the permanent magnet (12) of the unequal thickness permanent magnet assembly is located at the front end of the permanent magnet (12) of the unequal thickness permanent magnet assembly; The stator core (13) on which the permanent magnets (12) of the unequal thickness permanent magnet assembly are mounted is sleeved inside the rotor core (11), and the stator core (13) and the rotor core (11) are coaxially distributed; The armature winding (14) of the armature winding assembly is embedded in the rotor iron core (11).

8. The synchronous motor according to claim 7, characterized in that: The permanent magnets (12) of the unequal thickness permanent magnet assembly are attached to the outer surface of the stator core (13).

9. The synchronous motor according to claim 7, characterized in that: The armature winding (14) is a double-layer distributed winding, a single-layer distributed winding or a concentrated winding.

10. The synchronous motor according to claim 7, characterized in that: The permanent magnets (12) of the unequal thickness permanent magnet assembly are magnetized in parallel or in radial direction.

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