基于恒定开关频率空间矢量调制的永磁同步电机直接转矩控制

文中分析了永磁同步电机直接转矩控制中转矩、磁链快速动态响应与其稳态脉动之间矛盾的关键问题，提出并深入分析了一种采用空间电压矢量调制、实现简单的解决方式，即采用电压调制获得空间电压矢量的优化组合，实现转矩、磁链误差的精确补偿，进而达到高性能的直接转矩控制效果，同时保证功率器件开关频率恒定。仿真和实验结果证明，引入空间矢量调制概念后，在保持优异动态响应特性不变的条件下，可有效提高永磁同步电机直接转矩控制系统的稳态运行性能，同时系统开关频率近似恒定。

SPACE VECTOR MODULATED BASED CONSTANT SWITCHING FREQUENCY DIRECT TORQUE CONTROL FOR PERMANENT MAGNET SYNCHRONOUS MOTOR

The main problem of the direct torque control (DTC) for permanent magnet synchronous motor (PMSM) was analyzed, i.e. the contradiction of fast dynamic response and the serious torque and flux linkage ripples. In the paper, a space vector modulation (SVM) technique was introduced to the conventional PMSM DTC system, and was analyzed throughly, in order to obtain a optimal resultant voltage vector for accurate torque and flux linkage control and, furthermore, to achieve a high performance PMSM DTC system with constant switching frequency. The simulation and experiment verified that the introducing of the SVM concept is capable of effectively improving the steady state performance and keeping the excellent dynamic performance of the PMSM DTC system simultaneously and remain the switching frequency constant.