A flux-switching permanent magnet motor suitable for extended-range electric vehicles

Abstract

The invention discloses a flux switching permanent magnet motor suitable for an extended range electric vehicle. The flux switching permanent magnet motor consists of a stator, a composite rotor, armature windings and a non-magnetic rotary shaft, wherein the composite rotor consists of a rotor outer iron core, a rotor inner iron core and an annular circular disc, the rotor inner iron core coaxially and freely sleeves the interior of the rotor outer iron core, the annular circular disc is fixedly connected with the axial end surfaces of the rotor outer iron core and the rotor inner iron core, the stator coaxially sleeves between the rotor outer iron core and the rotor inner iron core, and consists of Ns H-shaped iron core modules and Ns permanent magnet steels which are alternatively arranged along the same circumferential direction, each permanent magnet steel is fixedly embedded between two adjacent H-shaped stator iron cores, the two adjacent permanent magnet steels are subject to tangential magnetizing and are opposite in direction, an inner groove and an outer groove are formed in each H-shaped iron core module, a stator yoke part is arranged between the corresponding two grooves, and each three-phase annular armature winding is arranged in the corresponding inner groove and the outer groove. The flux switching permanent magnet motor has the advantage that the torque output capability and power density of the motor are improved.

Description

technical field [0001] The invention belongs to the technical field of motor manufacturing, in particular to a permanent magnet motor suitable for electric vehicles and the like requiring high power density, high torque density, high efficiency and the like. Background technique [0002] Electric Vehicles (EVs) have significant advantages such as high efficiency, cleanliness, and safety. However, the current power batteries of electric vehicles have problems such as high price, low energy density, and long charging time, which limit the large-scale application of electric vehicles. Promote apps. Under the background that the power battery cannot obtain a large performance improvement in the short term, various forms of hybrid vehicles have emerged as the times require. Among them, Extended range electric vehicles (EREVs for short) are the most influential new models; the so-called extended range electric vehicles refer to changing the power structure of electric vehicles an...

AI Technical Summary

Problems solved by technology

Chinese patent No. 201410053207.5 proposes a permanent magnet rotor drive motor embedded in an electric vehicle. The permanent magnets on the rotor are arranged in a circular arrangement with in-line alternate tangential magnetization. The magnetic air gap is separated from the rectangular slot. Through this special design, the motor has significant magnetic accumulation characteristics and reduces the risk of irreversible demagnetization of permanent magnet steel; however, the motor structure has large torque ripple and rotor heat dissipation. And because of the special design of the permanent magnet magnet steel embedded rotor, the mechanical robustness of the rotor is greatly reduced, so its application will be severely limited

Chinese patent No. 201310173635.7 proposes a six-phase flux switching permanent magnet motor. The stator core is composed of a "U" shaped permeable core and permanent magnets embedded in each tangentially alternately magnetized core. Assembled with steel, the rotor has no winding and no permanent magnet steel, and only silicon steel sheets are laminated to form a salient pole structure; this motor belongs to the category of stator permanent magnet brushless motors, and has the inherent characteristics of high power density and high efficiency; due to the use of The special design of the six-phase winding reduces the requirements for the power converter compared with the three-phase motor at the same power level. With the increase of the number of phases, the number of space harmonics that have a greater impact increases, and The amplitude decreases, thereby reducing the amplitude of torque ripple; however, as the number of phases increases, the number of assembled "U"-shaped magnetic cores of the motor increases, and the amount of permanent magnet steel also increases

In addition, there is an inevitable magnetic flux leakage problem in the outer circle of the stator of the motor, which increases the eddy current loss of the motor and reduces the utilization rate of the permanent magnet steel

Chinese Patent No. 201310069627.8 proposes a radial magnetic field double-stator vernier motor. The rotor is in the form of a ring, and a number of permanent magnets are evenly spaced on the circumference of the ring. The inner and outer stators are salient pole structures. The armature windings Placed in the groove of the stator; the motor belongs to the category of stator permanent magnet brushless motor, which has higher torque and power density than the traditional single-layer air gap permanent magnet motor. positional relationship to obtain a higher power factor; however, there are two sets of windings and two layers of air gaps in the motor as a whole, so the size design of the motor is almost twice that of an ordinary single-layer air gap motor, and the power density will be reduced. In addition, The rotor of the motor is composed of a number of evenly spaced permanent magnets, and its mechanical robustness is severely affected

Therefore, the applicable occasions of the motor will also be subject to certain restrictions

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