基于模糊逻辑的永磁同步电动机直接转矩控制

Direct Torque Control of a Permanent Magnet Synchronous Motor Based on Fuzzy Logic

对永磁同步电动机直接转矩控制系统特性进行了深入分析 ,对其动、静态特性的改善进行了深入研究。以提高系统响应速度和减小转矩脉动为目标引入了模糊逻辑思想 ,将定子磁链误差、转矩误差和磁链角度进行了合理的模糊分级 ,以利准确选择电压空间矢量 ,改善磁链、转矩的平稳性及快速性。将定子磁链角度进行映射处理 ,以减少模糊控制规则数 ,缩短控制计算时间 ,加快响应速度。仿真结果表明 。

Firstly,the basic theory of the Direct Torque Control(DTC) on a Permanent Magnet Synchronous Motor(PMSM) is analyzed and then the difference of applying DTC on Induction Motor(IM) and on PWSM is also pointed out to decide a specific strategy for DTC on PMSM.In PMSM of DTC,an inverse voltage space vector was selected instead of the zero voltage space vectors in DTC on IM to enhance the torque response.For the sake of improving the static and dynamic performance of the system,fuzzy logic idea is introduced into the system.In the fuzzy DTC system,the stator flux linkage error,torque error and flux linkage angle of PMSM were all properly fuzzified into several fuzzy subsets to accurately select the voltage space vector in order to smooth the torque,flux linkage and quicken their response.The stator flux linkage angle was also mapped onto a limited region to minimize the number of fuzzy rules,shorten computation time and improve the response speed.Simulation results indicated that the fuzzy DTC strategy,which is designed base on the characteristic of the PMSM,is able to achieve more superior operation performance than that of the conventional DTC.