Analysis of voltage vectors and realization method of torque ripple reduction for BLDCM

Abstract BLDCMs are widely used in automotive, industrial and intelligent equipment fields due to their high power density, simple control, and good dynamic performance. However, its non‐sinusoidal characteristics have brought problems such as turn‐off phase freewheeling to the research and application of BLDCM DTC. This paper proposes the definition, particular characteristic analysis, selection scheme and realization method of the voltage vector, especially the novel zero‐voltage vector. Based on the novel zero‐voltage and twelve‐sector vector selection switch table, an improved PWM modulation strategy in a single cycle is proposed to cooperate with them to achieve the reduction of torque ripple. Finally, the correctness and feasibility of the proposed voltage vector and control strategy theory are verified by a series of experiments.