System of dead-beat direct torque control of permanent magnet synchronous motor

CHEN Yin，SUN Dan，LIN Bin

（College of Electrical Engineering，Zhejiang University，Hangzhou 310027，China）

Abstract：In order to solve the problems existed in the traditional direct torque control（DTC），such as high flux and torque ripples and unfixed switching frequency，a dead-beat direct torque control（DB-DTC）was proposed to control the permanent magnet synchronous motor （PMSM）. The DB-DTC scheme used the discretization equation of PMSM and the principle of dead-beat control to calculate the voltage vector，then SVM technique was combined to generate switching signals. Moreover，in order to eliminate the control period error brought by the time-consuming of discrete system calculation，a current observer was introduced to predict the current value in the next period，so

as to precisely evaluate the stator flux and torque. The experimental results confirmed the effectiveness of the scheme proposed. The DBDTC system has good dynamic and static performance，and the current observer can predict the stator current to ensure the control precision.