Variable structure techniques applied to sensorless speed control of permanent magnet synchronous motors

Abstract

A variable structure field oriented controller is applied to a permanent magnet synchronous motor (PMSM). The controller bases its action on the estimated values of the emfs induced by the moving rotor on the stator windings. Variable structure observers are used to derive the back emfs and the load torque. Simulation results are presented, showing the excellent performance of the proposed controller.