Sliding Mode Current Observer for Sensor less Vector Control of PMSM

The sensorless control system of permanent magnet synchronous motor is a system with an uncertainty and external disturbance. This paper uses the control law of equivalent control matched with switching control according to the theory of variable structure with sliding mode control, and achieves a robust control of the uncertainty and external disturbance. In order to eliminate the adverse effect caused by the chattering of the sliding mode, a saturation function of the quasi-sliding mode is used instead of the traditional sign function. Simulations and experiments prove that this control technology has a nicer dynamic and static performance.