Stator magnetism gathering type mixed permanent magnet memory motor

Abstract

The invention discloses a stator magnetism gathering type mixed permanent magnet memory motor and belongs to the field of adjustable magnetic flux permanent magnet motors. The stator magnetism gathering type mixed permanent magnet memory motor comprises a rotor and stator cores which are both of a salient pole structure. A stator of the motor comprises the six T-shaped stator cores, embedded alnico permanent magnets, neodymium iron boron permanent magnets embedded between the two adjacent T-shaped stator cores and a whole layer of stator yoke. In the magnetism increasing operation, the alnico permanent magnets and the neodymium iron boron permanent magnets of a V-shaped magnetism gathering type structure of adjacent stator units form the magnetism gathering effect to provide air gap main flux, and in the weak magnetism operation, the neodymium iron boron magnetic potential is short circuited by a large amount in the stator cores by alnico. The alnico permanent magnets conduct magnetizing towards the interior or the exterior of a circle center in parallel and are opposite in polarity, the design of magnetizing in the tangential direction and alternative distributing of polarities is adopted for the neodymium iron boron permanent magnets. According to the stator magnetism gathering type mixed permanent magnet memory motor, due to the arrangement of the stator magnetism gathering type mixed permanent magnets, the power density of the motor is improved, pulse current is exerted for adjusting the residual magnetization intensity and the magnetization direction of the permanent magnets, and the efficient adjustment of a no-load air-gap magnetic field of the motor is achieved.

Description

technical field [0001] The invention relates to an adjustable magnetic flux permanent magnet motor, which belongs to the field of adjustable magnetic flux permanent magnet motors. Background technique [0002] In the field of motors, due to the inherent characteristics of ordinary permanent magnet materials (such as NdFeB), the air gap magnetic field in the motor is basically kept constant, and the range of speed regulation is very limited when operating as an electric motor. The application of wide-speed adjustable direct drive applications such as electric vehicles and aerospace is limited to a certain extent. Therefore, the adjustable flux permanent magnet motor aimed at realizing the effective adjustment of the air gap magnetic field of the permanent magnet motor has always been a hot spot and difficulty in the field of motor research. . Traditional PMSMs use direct-axis current for field-weakening speed regulation, but it is difficult to achieve high-efficiency field r...

AI Technical Summary

Problems solved by technology

[0006] However, the air-gap magnetic field of the traditional stator permanent magnet motor is generated by the excitation of NdFeB permanent magnets, which is difficult to adjust, which limits its application in the wide-speed drive of electric vehicles; secondly, there is the problem of magnetic flux leakage at the end. rate is not high, resulting in electromagnetic compatibility problems

[0007] The hybrid excitation stator permanent magnet motor realizes the adjustability of the air gap magnetic field, improves the utilization rate and power density of the permanent magnet, and has the advantages of small cogging torque; however, this motor has two magnetic potential sources at the same time, and the two magnetic It is easy to couple with each other and influence each other, which increases the complexity of electromagnetic characteristics, and has weaknesses such as increased excitation loss and difficulty in implementing the excitation current control system.

[0008] Patent CN200910196558.0 discloses a doubly salient pole memory motor. For the first time, the concept of "memory motor" is integrated into the stator permanent magnet motor to achieve efficient online magnetic adjustment, but the motor only uses low coercive force aluminum Nickel-cobalt permanent magnets, and based on the double-saliency operation mechanism, the motor has a unipolar flux linkage and a back EMF close to the trapezoidal wave, which makes the torque density and torque ripple of the motor larger, and the industrial applicability is poor. In addition, The armature slot area of ​​the motor is smaller than that of the pulse winding slot, which greatly reduces the power density and force performance of the motor

In short, the above-mentioned hybrid excitation and memory motors generally have the problems of large magnetic capacity and low torque density. Therefore, a memory motor with high torque density is proposed for industries such as wind power generation, new energy vehicles, and multi-electric aircraft / ships. domain has significant significance

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