Sensorless Vector Control of PMSM in Wide Speed Range

Abstract

In order to achieve the sensorless vector control of PMSM in wide speed range, a hybrid control mode strategy is presented, which included sliding mode observer (SMO) and high frequency injection (HFI). At medium or high speed, sliding mode observer method that was based on fundamental wave model is applied to estimate of speed and position of PMSM. While at low speed, for avoiding the shortcomings of SMO, it had to switch to the HFI method. Firstly, the application of SMO method was achieved and the speed limit of SMO method is calculated, and it is as basis for switching region of the speed of the hybrid mode. The simulation results show that the hybrid mode can reduce the buffet in the procedure of switching of algorithm effectively. And it achieves the control of PMSM in wide speed range.