Starting methods for hall-less single phase BLDC motor

This paper is mainly about the starting methods for single phase brushless DC motor (BLDCM) under Hall-less driving. Because the rotor initial position is unknown when without Hall sensor, it is difficult for the controller to control the motor to rotate in the predefined direction in start-up. Here, the paper develops two different starting methods to realize right start-up under Hall-less driving. In one of the methods, by pulling the rotor to a known position with a special current pulse, the controller can control the direction easily. While in the other method, the controller can make the rotor rotate in the predefined direction just by applying a current pulse to the winding. Both of the methods are simple and feasible.