The modeling and simulation of PMSM basing on the sliding mode observer

The paper focus on the modeling, control and simulation method of permanent magnet synchronous motor-PMSM basing on sliding mode observer. To get the rotor speed without the sensor, firstly, the extended back electromotive force (EEMF) is estimated using voltage and current in the α-β coordinating system, and the control strategies are derived by selecting deliberately the sliding mode surface. Secondly, the input signals of the voltage and current in α-β plane approaches continuously and eventually coincides with the selected surface. Finally, the speed and position of the PMSM’s rotor are calculated based on the estimated variables to achieve control of the motor. To validate the feasibility of the method, a detail model with the speed/position observer was developed in Simulink. The comparisons with conventional position sensor confirmed that sliding mode observer exhibits good robustness and feasibility in PMSM control.