CN203788059U - A Parallel Hybrid Magnetic Material Motor - Google Patents

Abstract

The utility model discloses a parallel-type hybrid magnet motor. The motor comprises an outer stator, an inner rotor and a three-phase alternating-current armature. The three-phase alternating-current armature adopts a concentrated winding manner, and is arranged on the outer stator. High-performance neodymium iron boron permanent magnet materials are mounted on the surface of the inner rotor, and low-performance ferrite permanent magnet materials are embedded in the surface of the inner rotor. The low-performance ferrite permanent magnet materials are surface-embedded on two sides of the high-performance neodymium iron boron permanent magnet material. The low-performance ferrite permanent magnet materials and the high-performance neodymium iron boron permanent magnet materials are arranged side-by-side. The magnetic circuit of the high-performance neodymium iron boron permanent magnet materials is parallel to that of the low-performance ferrite permanent magnet materials. According to the utility model, the ferrite materials and the neodymium iron boron materials are surface-embedded and surface-mounted on the inner rotor, and the motor rotor is easy to process.

Description

A Parallel Hybrid Magnetic Material Motor

technical field

The utility model relates to a motor, in particular to a parallel-connected hybrid magnetic material motor. the

Background technique

In recent years, with the development of high-performance permanent magnet materials, permanent magnet motors have made great progress. This type of motor has the characteristics of small size, high power density and high efficiency. However, in recent years, the price of rare earth permanent magnet materials has been rising steadily. How to reduce the manufacturing cost of permanent magnet motors has become a research hotspot. It can be seen from domestic and foreign literature that the method of reducing rare earth permanent magnet materials is generally divided into two types: one is to use low-priced ferrite to replace high-priced NdFeB materials; the other is to use mixed excitation, using The electric excitation complements the permanent magnet excitation. the

Ferrite materials are used instead of NdFeB materials because ferrite materials have the following outstanding advantages: low price, no rare earth materials; simple manufacturing process; large coercive force; strong demagnetization ability. In the document "Alternative rotor designs for high performance brushless permanent magnet machines for hybrid electric vehicles" (published in IEEE Transactions on Magnetics Volume 48, Issue 2, Pages 835-838 in 2012), the radial motor structure was successfully replaced by ferrite NdFeB, and make this low-performance ferrite motor characteristics comparable to high-performance NdFeB motors. On this basis, the document "Design and analysis of a spoke type motor with segmented pushing permanent magnet for concentrating air-gap flux density" (published in IEEE Transactions on Magnetics Volume 49, Issue 5, Pages 2397-2400 in 2013) was approved Adding the magnetic gathering ring of ferrite increases the magnetic density of the air gap in the motor. In the permanent magnet motor using the hybrid excitation method, the excitation includes the permanent magnet excitation of NdFeB and also includes electric excitation. Compared with permanent magnet excitation, the armature excitation effect is generally relatively small. Therefore, the armature excitation in the hybrid excitation permanent magnet motor is a supplement and adjustment to the excitation of the NdFeB permanent magnet.

On the other hand, the existing traditional surface-mounted permanent magnet motor with concentrated winding has a trapezoidal back EMF, that is, the harmonic component in the back EMF is relatively high. The output torque ripple of the permanent magnet motor with high harmonic content back emf is also larger. In order to reduce the harmonic content of back EMF in surface-mounted permanent magnet motors, the document "On the use of pulse width modulation method for the elimination of flux density harmonics in the air-gap of surface PM motors" was published in IEEE Transactions in 2009 on Magnetics Volume 45, Issue 3, Pages 1736-1739), the permanent magnet is discharged by PWM, which greatly reduces the harmonic content in the back EMF.

Utility model content

Aiming at the problems existing in the prior art, the purpose of this utility model is to propose a parallel type that has a high sinusoidal back EMF, can reduce the amount of rare earth permanent magnet materials, and uses low-performance ferrite and high-performance NdFeB at the same time. Hybrid magnetic material motor. the

In order to achieve the above purpose, the utility model adopts the following technical solutions: a parallel hybrid magnetic material motor, including an outer stator, an inner rotor and a three-phase AC armature, the three-phase AC armature adopts a concentrated winding, and the outer stator A three-phase AC armature is placed on the inner rotor, NdFeB permanent magnet materials are pasted on the inner rotor, ferrite permanent magnet materials are embedded on the inner rotor, and NdFeB permanent magnet materials are embedded on both sides of the NdFeB permanent magnet material. The ferrite permanent magnet material, the ferrite permanent magnet material and the NdFeB permanent magnet material are arranged side by side. the

The magnetic circuits of the NdFeB permanent magnet material and the ferrite permanent magnet material are connected in parallel. the

After adopting the above technical solution, the utility model has the following beneficial effects: 1. The ferrite and NdFeB of the utility model are surface-embedded and surface-attached on the inner rotor, and the motor rotor is easy to process. the

2. The ferrite and NdFeB of the utility model are arranged side by side, so that the low-performance ferrite and the high-performance NdFeB magnetic circuit are connected in parallel. the

3. The utility model makes full use of the performance difference between ferrite and NdFeB in the parallel magnetic circuit, so that the NdFeB produces the wave top part of the sinusoidal back EMF, and the ferrite produces the wave bottom part of the sinusoidal back EMF. Due to the simultaneous use of NdFeB and ferrite, the amount of NdFeB used is reduced. In this way, the hybrid magnetic material motor not only obtains a highly sinusoidal counter electromotive force, but also reduces the cost of the motor. the

Description of drawings

Fig. 1 is a structural representation of the utility model;

Figure 2 is the magnetization direction of ferrite and NdFeB;

Figure 3 is a ferrite and NdFeB magnetic circuit;

Figure 4 is a traditional surface mount permanent magnet motor;

Figure 5 is a comparison of back EMF;

Figure 6 is a harmonic analysis comparing the back EMF;

In the figure: 1. Outer stator; 2. Three-phase AC armature; 3. Inner rotor; 4. High-performance NdFeB permanent magnet material; 5. Low-performance ferrite permanent magnet material.

Detailed ways

The utility model will be further explained below according to the accompanying drawings and specific embodiments of the description. the

As shown in Figure 1, a parallel-connected hybrid magnetic material motor includes an outer stator 1, an inner rotor 3, and a three-phase AC armature 2, and the iron cores of the outer stator 1 and inner rotor 3 are punched and stacked with D23 materials commonly used in China. Pressed. The three-phase AC armature 2 adopts concentrated winding, the three-phase AC armature 2 is placed on the outer stator 1, and the high-performance NdFeB permanent magnet material 4 is pasted on the inner rotor 3. The upper surface of the inner rotor 3 is embedded with low-performance ferrite permanent magnet material 5, and the surface of the high-performance NdFeB permanent magnet material 4 is embedded with low-performance ferrite permanent magnet material 5. The low-performance ferrite permanent magnet material 5 and the high-performance NdFeB permanent magnet material 4 are arranged side by side. the

As shown in FIG. 2 , the magnetization directions of the low-performance ferrite permanent magnet material 5 and the high-performance NdFeB permanent magnet material 4 are shown. Every two ferrites and the NdFeB in the middle form a set of excitation. The magnetization direction of each group of permanent magnet materials is consistent, pointing to the center of the circle or away from the center of the circle. Adjacent groups of permanent magnets are magnetized in opposite directions. After the magnetization directions of the low-performance ferrite permanent magnet material 5 and the high-performance NdFeB permanent magnet material 4 are determined, the high-performance NdFeB permanent magnet material 4 and the low-performance ferrite permanent magnet The magnetic circuits of the magnetic material 5 are connected in parallel. the

As shown in Figure 3, the stator teeth in the dashed box can be seen that the magnetic field lines passing through the stator teeth are produced by both high-performance NdFeB permanent magnet materials 4 and low-performance ferrite permanent magnet materials 5 of. At this time, the low-performance ferrite permanent magnet material 5 and the high-performance NdFeB permanent magnet material 4 can be regarded as two low-performance and high-performance power supplies connected in parallel in the magnetic circuit. the

In order to fully reflect the advantages of the hybrid magnetic material motor, as shown in Figure 4, a comparison of its performance with the traditional surface-mounted motor is given. It can be seen from the figure that the permanent magnets excited in the traditional surface-mounted motors are only NdFeB. the

Figure 5 shows the back EMF waveforms of the single-turn concentrated windings of the two models. It can be seen from the figure that the back EMF of the hybrid magnetic material motor is sinusoidal, while the back EMF of the traditional surface-mounted motor is trapezoidal. the

As shown in Figure 6, the Fourier analysis of the back EMF, it can be seen from the figure that when the back EMF fundamental wave amplitude of the hybrid magnetic material motor is basically similar to that of the traditional surface-mounted motor, the hybrid magnetic material motor’s The third harmonic is significantly reduced, so the parallel hybrid magnetic material can obtain a highly sinusoidal back EMF. At the same time, comparing the NdFeB consumption of the two motors at this time, it can be seen that the NdFeB consumption of the parallel hybrid magnetic material motor is only about 86% of that of the traditional surface-mounted motor. the

Claims (2)

1. A parallel type hybrid magnetic material motor, comprising an outer stator, an inner rotor and a three-phase AC armature, characterized in that the three-phase AC armature adopts a concentrated winding, and a three-phase AC armature is placed on the outer stator, so The inner rotor is pasted with NdFeB permanent magnet material, the inner rotor is embedded with ferrite permanent magnet material, and both sides of the NdFeB permanent magnet material are embedded with ferrite permanent magnet material, so The ferrite permanent magnet material and the NdFeB permanent magnet material are arranged side by side. 2. A parallel-connected hybrid magnetic material motor according to claim 1, characterized in that the magnetic circuits of the NdFeB permanent magnet material and the ferrite permanent magnet material are connected in parallel.