A Novel Sensorless Commutation Technique for BLDC Motors Phase‐Delay Elimination and Enhanced Error Compensation

ABSTRACT Interference pulses from commutation freewheeling impact the detection accuracy of brushless direct current (BLDC) motors. Interference pulses are commonly filtered using a low‐pass filter (LPF) with a low cutoff frequency. However, this approach introduces phase delay, which can adversely affect motor performance. This paper proposes a novel sensorless commutation method based on terminal voltages. The method employs a hysteresis transition between zero‐crossing point sequence recognition (ZSR) and a fixed delay digital filter (FDF) to address these interference pulses. To address residual commutation errors due to non‐ideal current, software delays, and circuit imperfections, an improved compensation algorithm incorporating virtual neutral voltage is introduced. This approach achieves double the convergence rate and higher accuracy compared to conventional methods, without additional hardware. Experimental results validate the effectiveness of the proposed method.