Electromagnetic Field Analysis Of Permanent Magnet Synchronous Motor In Electric Vehicles

Energy, environmental and climate change issues are society problems for a long-term. To reduce the greenhouse gas emissions by traffic field is an important means to solve global climate change. Therefore, electric vehicles have got rapid development in the world. Compared with the traditional electrical excitation synchronous motor, permanent magnet synchronous motor gains advantages of low loss, high efficiency and obvious energy saving effect, especially rare earth permanent magnet synchronous motor. Permanent magnet provides excitation to the permanent magnet synchronous motor, so the motor has a simple structure, reducing the processing and assembly costs and improving the reliability, efficiency and power density of motor operation. The permanent magnet synchronous motor has been widely applied in various fields especially in the electric vehicles field. Nowadays, it is paid more and more attention in energy conservation and environmental protection, therefore, the research is very necessary.Electromagnetic field analysis of motor is the basic work for the performance of the motor. This paper discusses the basic principle of permanent magnet synchronous motor including the basic structure, category and working characteristics. The permanent magnet synchronous motor is analyzed and calculated with finite element method. Then, the calculation model of the motor is established with finite element analysis software Ansoft. The no-load magnetic field of permanent magnet synchronous motor research had analyzed, and calculated the radial air-gap flux density, back electromotive force, pole arc coefficient, leakage coefficient and gap waveform factor. At the same time, the rated load field of the motor is calculated and analyzed. The important parameters of the motor are got though two proceeds, such as d-q axis armature reaction reactance.Electric vehicle parameters of permanent magnet synchronous motor have important influence on electric vehicle performance, so this paper had a deeply research on it. The impact of the motor performance is analyzed by structure parameters. The influenced of motor performance which caused by the change of structure parameters is discussed, the structure parameters are permanent magnet magnetization direction length, width of permanent magnet, the stator winding turns, air gap length and the armature slot width. And, the design of permanent magnet motor is optimized.