Sensorless Control of PMSM in Low Speed Region Using HF Pulse Signal Injection Method

The sensorless control of the permanent magnet synchronous motor (PMSM) has attracted wide attention due to its economic and safety benefits. A fast and high-precision rotor-position estimation is necessary for the implementation of sensorless control. In low-speed region, high frequency (HF) signal injection methods are mostly adopted. They suffer to bandwidth deterioration as some digital filters must be included in the current feedback loop or the speed observation signal processing. The HF signal injection method based on the injection of voltage pulses is presented in this paper together with its implementation in MATLAB/Simulink. The method is based on the injection of voltage pulses where injection itself is separated from the motor control algorithm. The simulation results show that the proposed method has good dynamic performance for the sensorless control of PMSM.