Control Trajectories for Interior Permanent Magnet Synchronous Motor Drives

This paper presents an analysis of control trajectories for indirect and direct control of interior permanent magnet (IPM) synchronous motor drives. Since the inputs to the inner torque control loop of direct torque control (DTC) are the references for the torque and the amplitude of the stator flux linkage (lambda_s), rather than i_d-i_q plane in the indirect control, are transformed into the T-lambda_s, plane. The experimental results show the excellent performance of the indirect and direct torque controller, incorporating control trajectories.