摘要：传统位置、速度和电流三环控制方法由于其简单高效等特点，在永磁同步电机平缝机中得到大量应用。但是在采用低精度编码器的伺服应用场合，其三环串联结构在低速时，会降低位置跟随性能。本文根据位置、电流两环的特点，针对平缝机停机过程设计了三环两环双模式的位置控制方法。仿真和实验结果验证了本方法的有效性。

关键词：平缝机;永磁同步电机;停机;双模式切换
Abstract: In common sewing machines applications of PMSM, the threeloop (position loop, speed loop and current loop) control mode has been largely used, because of its simplicity and efficiency. However, the threeloop control mode has a speed and position lag when it comes to low speed, with a low precision encoder. This paper presented a halt method for sewing machines, which had a dual mode consisted of threeloop and twoloop. The simulations and the experiment show the validity of the method. 

Key words: sewing machines; PMSM; halt; dual mode