在永磁同步电机的运动控制系统中采用直接转矩控制策略，其性能的优劣程度取决于磁链和电磁转矩的控制情况，因此很有必要进一步的研究控制系统转矩和磁链的性能。-Permanent magnet synchronous motor is widely used in the field of speed control systems because of its various high performance,such as its small volume, high efficiency, reliable work performance, and the advantage of being able to adapt to harsh environment.Direct torque control technology regards the induction motor as the research object , because its idea is novel , its architecture is simple and it has excellent static and dynamic performance of the system , so this technology has received extensive attention.This paper focuses on the surface mounted permanent magnet synchronous motor, and the main work is as follows at direct torque control system.