A new starting method for 12/8-pole doubly salient permanent-magnet motors without position sensor

This paper presents a new sensorless starting method for 12/8-pole doubly salient permanent-magnet (DSPM) motors. The method can detect the rotor position at standstill, and then a specific start-up method is used to accelerate the motor up to a middle-speed where conventional sensorless control algorithms based on the back-EMF can work properly. The proposed scheme employs only one current sensor at DC-link side of the inverter, and can be applied to a motor without knowing its parameters and additional position sensors. The proposed initial rotor position detection technique has a resolution of 30 electrical degrees. The simulated results of the starting procedure based on MATLAB/Simulink reveal the effectiveness of the proposed method.