Abstract:The traditional sensorless control detects the motor position by using the back electromotive force of the motor,which can effectively reduce the hardware cost and occupied area,but there are some problems such as start-up difficulty and start-up reverse rotation.Aiming at those problems,a method of applying pulse current and detecting the change of winding inductance was proposed to determine the initial rotor position,and cooperated with FOC algorithm to control the smooth and efficient operation of BLDC motor.In addition,the optimization of control advance angle and the anti-load disturbance performance of the motor were analyzed,which further improved the operation efficiency and anti-interference ability of the whole system.Finally,an experimental prototype was built to verify it.The experimental results show that the prototype can realize no reverse rotation,efficient and reliable start-up without position sensor,and realize efficient operation under FOC closed-loop control.