基于PLL技术的BLDCM转子位置检测

Method of detecting rotor position of sensorless brushless DC motor based on the PLL technology

为了准确检测无位置传感器无刷直流电机(BLDCM)转子位置信号,通过分析无刷直流电机的PWM-ON-PWM调制方式,结合锁相环(PLL)技术,提出一种新型转子位置检测方法,首先对绕组的端电压和线电压差进行求和运算,然后再与3/2倍的电源电压作比较,得到悬空相的反电动势过零点,最后通过锁相环倍频技术锁定最佳换相时刻。从仿真结果来看,通过此方法能够检测到转子位置信号,从而实现电机绕组的准确换相,因此表明此方法可行有效。

In order to detect accurately the rotor position signal of sensorless brushless DC motor（ BLDCM）,through the analysis of PWM-ON-PWM modulation of brushless DC motor,combined with the phase-locked loop technology,this paper puts forward a novel rotor position detection method.Firstly,it adds winding terminal voltage and line voltage difference,then compares to 3 /2 times the power supply voltage, obtains the floating phase back-EMF zero crossing, finally by frequency multiplication phase-locked loop technology lock best commutation time. The simulation results show this method can detect the rotor position signal,so as to realize the accuracy of motor winding commutation.It shows that this method is feasible and effective.