基于硬件滤波电路的无刷直流电机转子位置辨识

反电动势过零检测是无刷直流电机无位置传感器控制中转子位置检测的主要方法之一，为消除PWM因素的影响，需要对转子位置检测电路进行滤波处理。本文采用硬件滤波器对反电动势过零检测电路进行滤波，既要考虑深度滤波带来的相移问题又要兼顾消除噪声的影响，分析滤波器的幅频特性和相频特性，根据反电动势过零检测指标要求设计滤波器参数，并用于无刷直流电机转子位置辨识和无位置传感器控制中。仿真结果和实验结果表明，所采用的滤波器及其参数能较好地检测出转子位置，可以明显提高无位置传感器无刷直流电机驱动系统的控制性能。

Identification of Rotor Position for Brushless DC Motor Drives Based on Hardware Filter Circuit

Zero-crossing detection of back electromotive force (EMF) is one of the main methods for the rotor position detection in sensorless control of brushless DC (BLDC) motor drives. To reduce the influence of pulse width modulation (PWM), the hardnare filter circuit for rotor position detection is dispensable. This paper proposes a hardware filter for the zero crossing detection of back EMF, and filtering is necessary to consider between the depth of the phase shift and the elimination of noise. The amplitude-frequency and phase-frequency characteristics of the filter are analyzed in detail. According to the requirement for the zero crossing detection of back EMF, The filter and its parameters are designed for the rotor position identification which is used to sensorless BDLC motor drives. The simulation and experimental results show that the proposed filters can detect the rotor position accurately and improve the control performance of sensorless BLDC motor drives.