This document introduces an algorithm for sensorless control of brushless direct current (BLDC) motors using dsPIC digital signal controllers (DSCs). The algorithm utilizes a multi-function digital filter for back-electromotive force (BEMF) to determine the timing of motor drive voltage commutation by filtering the BEMF signals of each motor phase. This control technology eliminates the need for discrete low-pass filtering hardware and external comparators. It is suitable for three-phase motors and offers advantages such as low cost and high efficiency.
This application note introduces an algorithm for implementing sensorless control of Brushless Direct Current (BLDC) motors using dsPIC digital signal controllers. The algorithm utilizes a majority function filter applied to digitally filtered Back-Electromotive Force (BEMF) signals to determine commutation timing. This approach eliminates the need for discrete low-pass filter hardware and external comparators, requiring only a few external resistors to scale the BEMF signal for the ADC. This manual is written in Chinese.