Research on the Method of AC Speed Control Based on the Combination of DTC & FOC

A new voltage adjust mean with Direct Torque Control (DTC) and Stator Flux Oriented Control (SFOC) combined is presented in this paper. First, by using FOC in the system, AC parameters can be converted in DC for convenient control. On the other hand,by using DTC the transient performance of the system can be improved. At the same time, by using the method of voltage control, current decoupling can be avoided by controlling the flux and torque continuously, and the torque ripple can be reduced. The effect of proposed method has been proven by simulation.