Study And Design On Permanent Magnet Synchronous Motor In Electric Vehicle Application And Its Design Platform

The permanent magnet synchronous motor has many advantages such as high efficiency, high power density, high control precision and little noise etc. Through design the magnetic circuit of the stator and rotor reasonably, we can get preferable weak field characteristics and high reluctance torque, these advantages are required in electric vehicles for PMSM. In addition, improving the design method and developing a fast and accurate electromagnetic design platform have important significance.Firstly, this paper introduces the performance requirements of driving motors in electric vehicles, contrasts the current situation and the developing trend of drive motors in electric vehicles. Through the comparison of the various types of the advantages and disadvantages of driving motor, this paper choose the permanent magnetic synchronous motor which can meet the technical property requirements of electric vehicles. And Then this paper introduces the basic structure and the mathematics model of permanent magnet synchronous motor, analyses the output torque of the motor, when the d-axis and q-axis inductance are different and the magnetic is same and the d-axis and q-axis inductance are same and the magnetic is different, and the field weakening ratio with different salient pole rate. According to the performance requirements of the drive motor in electric vehicles, this paper designs the motor with its magnetic circuit of stator and rotor, the size of permanent magnet. And so on, introduces the major parts of the design detailed, and gives the examples. Based on the conventional design methods, this paper use VA language to write the motor electromagnetic computing design platform, it realized calculate the motor’s parameters fast and accurately. The theory of the electromagnetic field for studying the motor is the most important theory, and finite element analysis software Ansoft is in common use in the theory of the electromagnetic field. So the theory of the electromagnetic field and the finite element analysis software were introduced in the forth section. In the last section,2d modeling simulations of coreless PMSM motor are done with the finite element analysis software Ansoft. The output torque and power are the two most important measures to test the field weakening ratio of PMSM, this paper use Ansoft and Matlab to simulate the output torque and power of the PMSM, the results of simulations shows the correctness of the mathematical and the maximum speed and maximum output power also meet performance requirements.