Permanent magnet synchronous motor

Abstract

The utility model belongs to the field of motors, in particular to a permanent magnet synchronous motor, which specifically comprises a stator (1), windings (2), permanent magnets (3) and a rotor core (4), a plurality of stator grooves are arranged on the inner circumference of the stator (1) of the motor, and the windings (2) are arranged in the stator grooves; the permanent magnets (3) are embedded in the peripheral surface of the rotor iron core (4); each permanent magnet (3) comprises a radially magnetized main magnetic pole and two pairs of symmetrical auxiliary magnetic poles, the magnetizing directions of the auxiliary magnetic poles and the direction of the main magnetic pole form included angles alpha 2 and alpha 3, the two pairs of auxiliary magnetic poles are respectively positioned on two sides of the main magnetic pole, the permanent magnets (3) are formed after splicing, and the shapes of the magnetic poles and the permanent magnets are optimized according to the scheme. Permanent magnets under each pole of the motor are divided into five blocks to concentrate magnetic lines of force, optimize a magnetic flux path and reduce magnetic resistance; a traditional permanent magnet is rectangular, and the permanent magnet is optimized and designed to be triangular through theoretical analysis, so that magnetic lines of force are utilized more effectively, and the magnetic field intensity of the motor is enhanced.

Description

Technical Field

[0001] This utility model relates to the field of motor manufacturing, and in particular to a permanent magnet synchronous motor. Background Technology

[0002] Existing permanent magnet synchronous motors can be categorized into surface-mounted motors, embedded motors, and Halbach array motors based on the structure and position of the magnets. Halbach array motors, due to their unique magnetization method, can generate high air gap magnetic flux density, which helps improve the motor's power density and efficiency. However, currently available Halbach array motors generally have limited ability to optimize air gap magnetic flux density, with most only able to increase the flux density amplitude by 30%, and harmonic content remaining high. Most Halbach array motors have an asymmetrical magnet distribution structure, and the uneven air gap magnetic field also increases torque ripple, affecting motor performance. Furthermore, the magnet structure design is highly complex, requiring precise design and manufacturing of multiple small permanent magnets, resulting in high processing costs. Utility Model Content

[0003] The purpose of this invention is to design a novel segmented double-layer magnet structure based on the existing ordinary Halbach array motor, so as to improve its air gap magnetic flux density amplitude and optimize the waveform, thereby optimizing the overall performance of the motor without increasing the complexity compared with the ordinary Halbach array magnet.

[0004] The technical solution of this utility model is to provide a permanent magnet synchronous motor, specifically including a stator, windings, permanent magnets, and a rotor core, characterized in that:

[0005] The inner circumference of the stator of the motor is provided with several stator slots, and the windings are arranged in the stator slots;

[0006] The permanent magnet is embedded on the outer circumferential surface of the rotor core. Each permanent magnet consists of a radially magnetized main magnetic pole and four pairs of symmetrical auxiliary magnetic poles with magnetization directions at angles α2 and α3 to the main magnetic pole direction. The two pairs of auxiliary magnetic poles are located on both sides of the main magnetic pole and are spliced ​​together to form a permanent magnet.

[0007] Furthermore, the angle between the main magnetic pole and the first pair of auxiliary magnetic poles is α2 = 18°, and the angle between the main magnetic pole and the second pair of auxiliary magnetic poles is α3 = 63°.

[0008] Furthermore, the radial length of the upper fan-shaped permanent magnet block in the main magnetic pole is h0, and the radial length of the lower layer is h. i The sum of the two always equals the radial length of the permanent magnet.

[0009] The beneficial effects of this utility model are as follows:

[0010] (1) The scheme optimizes the shape of the magnetic poles and permanent magnets. The magnetic poles under each pole of the motor are divided into 5 blocks to concentrate the magnetic lines of force, optimize the magnetic flux path, and reduce magnetic resistance. The traditional permanent magnet is rectangular in shape. This invention optimizes its design into a triangle through theoretical analysis to make more effective use of the magnetic lines of force and enhance the magnetic field strength of the motor.

[0011] (2) This scheme combines permanent magnets with different magnetization directions to adjust and optimize the magnetic field distribution inside the motor.

[0012] (3) The scheme adopts a double-layer permanent magnet structure. The traditional permanent magnet is a single layer. After theoretical analysis, this utility model optimizes the design of the permanent magnet under each pole from a single layer to a double layer. By changing the pole arc coefficient of the upper and lower permanent magnets, a higher air gap magnetic flux density is obtained.

[0013] (4) The double-layer segmented permanent magnet structure designed in this scheme is simple in structure, easy to process, and can significantly improve the motor torque. These improvements enable the motor to maintain high performance under various working conditions, while reducing energy consumption and lowering operating costs. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the permanent magnet synchronous motor described in this utility model;

[0015] Figure 2 This is an exploded view of the permanent magnet synchronous motor described in this utility model;

[0016] Figure 3 This is a schematic diagram of a 3-piece permanent magnet structure;

[0017] Figure 4 This is a schematic diagram of a 5-piece permanent magnet structure;

[0018] Figure 5 This is a schematic diagram of a 7-piece permanent magnet structure;

[0019] Figure 6 Yes, it's a motor structure;

[0020] Figure 7 This is a schematic diagram of a double-layer convex permanent magnet structure;

[0021] Wherein: 1-stator, 2-winding, 3-permanent magnet, 4-rotor core. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the embodiments described with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot limit the scope of the present invention.

[0023] like Figure 1-2As shown, this embodiment provides a permanent magnet synchronous motor, specifically including a stator 1, windings 2, permanent magnets 3, and a rotor core 4, wherein:

[0024] The stator 1 of the motor contains 12 slots, and the windings 2 are arranged in the slots. The slots are evenly distributed on the inner surface of the stator to generate a uniform magnetic field.

[0025] The permanent magnet 3 is the core component of the motor and is located on the magnetic poles of the rotor core 4.

[0026] In this embodiment, the permanent magnet under each pole is subdivided into different numbers of blocks to optimize the magnetic flux path and reduce magnetic resistance. The shape of the permanent magnet is optimized from the traditional rectangle to a triangle, and the shape is optimized from a single layer to a double layer to more effectively concentrate magnetic lines of force and enhance magnetic density.

[0027] In addition, the permanent magnets 3 are combined with different magnetization directions to further adjust and optimize the magnetic field distribution inside the motor. All permanent magnets 3 are embedded on the surface of the rotor core 4.

[0028] When the motor is energized, the current in the stator winding 2 interacts with the magnetic field generated by the permanent magnet 3 of the rotor core 4, inducing an electromotive force in the stator winding 2. As the rotor core 4 rotates, the magnetic field generated by the permanent magnet 3 continuously changes. This changing magnetic field interacts with the current in the stator winding 2, generating an electromagnetic force, which is then converted into torque, driving the rotor core 4 to rotate. This torque is connected to the motor's load, thus realizing the output of mechanical work.

[0029] The permanent magnet 3 described in this embodiment is an improvement on a conventional rectangular magnet. Firstly, considering that a higher number of magnet blocks results in a better sinusoidal waveform in the motor's air gap magnetic flux density, and taking into account practical feasibility, three types of magnetic pole structures—3, 5, and 7 blocks per pole—were selected for analysis.

[0030] like Figure 3 The diagram shows a three-piece permanent magnet structure, consisting of a radially magnetized main magnetic pole and two symmetrically distributed auxiliary magnetic poles whose magnetization direction forms an angle α1 with the direction of the main magnetic pole, where α1 = 27°.

[0031] Figure 4 The diagram shows a five-piece permanent magnet structure, consisting of a radially magnetized main magnetic pole and four symmetrical pairs of auxiliary magnetic poles whose magnetization directions form angles α2 and α3 with the main magnetic pole direction, where α2 = 18° and α3 = 63°.

[0032] Figure 5The diagram shows a 7-piece permanent magnet structure, consisting of a radially magnetized main pole and six symmetrical pairs of auxiliary poles, each with an angle of α4, α5, and α6 between their magnetization directions and the main pole direction, respectively. α4 = 10°, α5 = 20°, and α6 = 30°. After simulation analysis, a 5-piece motor was ultimately retained.

[0033] like Figure 7 As shown, this embodiment maintains the original single-layer permanent magnet volume and magnetization direction unchanged, and optimizes the design into a double-layer "convex" permanent magnet structure based on the single-layer structure. The radial length of the upper fan-shaped permanent magnet block in the main magnetic pole is h0, and the radial length of the lower layer is h. i The ratio of the two is k, and their sum always equals the radial length of the permanent magnet; the pole arc coefficient of the motor is 1, the arcs of the upper and lower magnetic poles are not equal, and the upper and lower structural parameters are α respectively. u α i Therefore, the structure of the main magnetic pole T1 is only related to h0 and h i The four parameters α, θ0, and θ0 are related, and by changing these parameters, the air gap magnetic flux density of the motor can be altered. While keeping the volume of the permanent magnet under each pole constant, different pole combinations are obtained by changing the upper and lower pole arc coefficients. Considering practical considerations, α is varied within the ranges of 0.5–0.9 and 0.78–0.97, respectively. u α i To obtain the optimal result, based on the specific model of the motor structure designed in this embodiment, five sets of data that meet the conditions were selected, as shown in Table 1. After simulation analysis, the first set of data showed the best performance, and the final motor structure is as follows. Figure 7 As shown.

[0034] Appendix 1

[0035]

[0036] The above embodiments are specific embodiments of this utility model. It should be noted that the implementation of this utility model is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc. made on the embodiments should be included in the protection scope of this utility model.

Claims

1. A permanent magnet synchronous motor, comprising a stator (1), a winding (2), a permanent magnet (3), and a rotor core (4), characterized in that: a plurality of stator slots are arranged on the inner periphery of the stator (1) of the motor, and the winding (2) is arranged in the stator slots; the permanent magnet (3) is embedded on the outer peripheral surface of the rotor core (4); each permanent magnet (3) comprises a main magnetic pole with radial magnetization and four pairs of auxiliary magnetic poles with symmetrical magnetization directions and included angles of α2 and α3 with the main magnetic pole direction, and the two pairs of auxiliary magnetic poles are respectively located on both sides of the main magnetic pole, and are spliced to form the permanent magnet (3).

2. The permanent magnet synchronous motor according to claim 1, characterized in that: the included angle between the main magnetic pole and the first pair of auxiliary magnetic poles is α2 = 18°, and the included angle between the main magnetic pole and the second pair of auxiliary magnetic poles is α3 = 63°.

3. The permanent magnet synchronous motor according to claim 1, characterized in that: The radial length of the upper layer sector-shaped permanent magnet block in the main magnetic pole is h0, and the radial length of the lower layer is h i , and the sum of the two is always equal to the radial length of the permanent magnet.

Images