Research On Optimization Design And Performance Test Of PMSM

As the key components, the design of PMSM is related to the dynamic performance, precision, reliability and efficiency of the robot, and the demand is huge. For PMSM R & D and manufacturing capability is relatively weak, quality is low in our country. The traditional calculation method based on equivalent magnetic circuit and empirical coefficient cannot meet the high precision, efficiency and complexity for the optimal design of the motor. Research on the optimization design of the PMSM based on the platform, more accurate analysis of the motor performance parameters and more optimized design of the motor, has great practical significance.Firstly, the analysis showed that period of the torque ripple and the cogging torque is different of PMSM with different number of poles and slots. The step skewing angle based on cogging torque periodicity is weakening effect on torque ripple. Thus a method of calculation step skewing angle is presented based on torque ripple periodicity. The validity of the proposed measure is verified by finite element analysis.Secondly, the influence of different kinds of permanent magnet shape and directions of magnetization on motor performances is analyzed. Permanent magnet shape and directions of magnetization is optimized, the experimental results show that the harmonic content of the back EMF is about 2%. In order to avoid irreversible demagnetization, the working point and demagnetization current of the permanent magnet is carried out on finite element analysis.Finally, an expression of the winding copper loss is derived under the condition that flux density of stator and the limitation of the flange size is constant. The model of the stator slot is established. The stator inner diameter is calculated to satisfy the requirement of torque and the minimum winding copper loss. According to the actual control algorithm and the carrier frequency, the vector control model is established by using Simplorer. Analysis of the motor internal magnetic field and iron losses, and compared with the experimental data. The results show that the iron loss increases greatly, is about 2 times, under the condition of the inverter power supply than sine wave power supply. Based on the analysis results of the winding copper loss and iron loss, the thermal network method is used to analyze the thermal resistance and the temperature of each node.