Sensorless BLDC Control with Back-EMF Filtering Using a Majority Function
Adrian Lita and Mihai Cheles
This application note describes a sensorless Brushless Direct Current (BLDC) motor control algorithm, implemented using the dsPIC® Digital Signal Controller (DSC). The algorithm works by the use of a majority function for digitally filtering the back-Electromotive Force (BEMF). Each phase of the motor is filtered to determine when to commutate the motor drive voltages. This control technique excludes the need for discrete, low-pass filtering hardware and off-chip comparators.
dsPIC, dsPIC30F, dsPIC33F, DSC, Digital Signal Control, DSP, 16-bit, Sensorless, BLDC, PMSM, Brushless