Position Sensorless Control for Permanent Magnet Synchronous Motor Using Sliding Mode Observer

摘要

An approach of position sensorless control for permanent magnet synchronous motor (PMSM) is put forward based on a sliding mode observer. The mathematical model of PMSM in a stationary αβ reference frame is adopted, and the system is controlled by the digital signal processor (DSP) TMS320LF2407 according to the control theory of sliding mode observer. In order to achieve closed loop operation of the motor, the stator magnetic field should be vertical with the rotor magnetic field and be synchronous with rotor rotating, so the position and speed of PMSM is estimated in real time and the estimated position is modified continuously. The simulation results indicate that the proposed observer has high precision in estimation of PMSM position and speed, and is more robust to the parametric variation and load torque disturbance.