Voltage vector selection area of permanent magnet synchronous motor direct torque control system

In order to suppress torque ripple of direct torque control(DTC) under the control of switching table,the effects of voltage vector on amplitude of stator flux,toque angle,excitation torque,reluctance torque and torque in permanent magnet synchronous motor(PMSM) DTC system are analyzed.Some simple mathematics equations are given to express the control principles of these variables.The voltage vector selection area of PMSM DTC system is proposed based on these control principles.The results show that the angle between applied voltage vector and stator flux(α) determines the increasing or decreasing effect of voltage vector on the amplitude of stator flux and torque angle.The torque angle determines the increasing or decreasing effect of voltage vector on excitation torque and reluctance torque.The torque angle and parameters of PMSM DTC system determine the increasing or decreasing effect of voltage vector on torque.