基于特征电流与定子饱和参数的IPM同步电机性能估算

摘要

Interior permanent magnet synchronous motors （IPMSM） can be widely used in the transmission system of electric vehicles （EVs）, which take the advantages of high output torque at low speed, high constant output power at high speed, and high efficiency. Since the magnetic field of IPMSM is designed to be saturated, which makes the output capacity of IPMSM sharply decreases in the high speed range. A method was developed to evaluate the performance of a series of IPMSM using the characteristic current and saturated stator parameters. The method takes maximum torque per Ampere （MTPA） strategy to achieve constant torque control at low speed and constant power speed ratio strategy to achieve constant power control at high speed to meet the requirement of electric vehicles, with output performance of IPMSM regulated by changing the values of the characteristic current compared with the current rates of the power module. Comparative simulation and test results using different prototypes with different parameters validate the accuracy and applicability of the method.%磁钢内置式永磁同步电机（IPMSM）由于其低速大出力、高速恒功率、宽调速、高效率等优越性能，可广泛应用于电动汽车传动系统等领域。由于磁场的饱和效应，使得IPMSM输出能力在高速情况下迅速降低。该文提出一种采用特征电流与定子饱和参数来精确评估IPMSM输出能力的方法。IPMSM在低速时采用最大转矩电流比（MTPA）控制，在高速时采用恒功率弱磁控制，实现电机宽调速、高效率性能，其输出性能可通过调整特征电流与功率模块最大可用电流的关系来进行调节。对不同样机的仿真与试验结果表明，该评估方法的估算精度高。