无位置传感器无刷直流电动机转子位置检测新技术

针对反电势法在电动机转子位置检测时存在迭加干扰和需要误差补偿等缺点，提出了一种新的检测方法，即在PWM导通期间对电机不导通相绕组端电压进行采样，判断绕组反电势过零点时刻，并结合位置预测方法对过零点时刻进行校正，推算逆变器中功率器件的切换时间。反电势检测电路设计简单，容易实现。实验证明，本文方案检测精度高、抗干扰能力强、可靠性高。

New Technology of Rotor Position Detection for Sensorless Brushless DC Motor

This paper presents a new method of rotor position detection because the back-EMF method has some shortcomings such as strong interference, needing compensation, and so on. The original back-EMF method is improved. We obtain the right time when back-EMF reaches the zero point through sampling non-conducted phase voltage during PWM-on phrase. We conduct emendation on the detection data by means of state predict, and then conclude the switch-on time of power transistor. Also, it is simple for hardware and easy for realization. As the results show, the method proves to be high precision, strong anti-interference ability and high dependability.