A new approach rotor speed estimation for PMSM based on sliding mode observer

This paper proposes a sensorless speed control strategy for a permanent-magnet synchronous motor (PMSM) based on a sliding-mode observer (SMO). In order to apply a sensorless PMSM control which is robust against parameter fluctuations and disturbances, a high-speed SMO is proposed, which estimates the rotor position and the angular velocity. The stability of the proposed SMO was verified using the Lyapunov method to determine the observer gain. At standstill, the type of sliding mode observer is not able to detect the rotor position. For this reason, we use the method of voltage pulses to detect it. The simulation results show the effectiveness of the observer with sliding mode. They are characterized by a very small estimation error for the various rotational speeds (high speed, low speed).