Torque ripple minimization via PWM control technique with GaN-based motor drive for high speed single phase brushless DC motor

This paper proposes a novel reference voltage controlled pulse width modulation technique to minimize the excitation torque ripple of a single-phase brushless DC motor for high-speed applications. The proposed control technique reduces output current ripple by modifying PWM reference voltage rather than shifting input voltage phase. The comparison results of output torque indicate that the proposed control technique has 91.82% lower torque ripple than that of the conventional control technique. The overall efficiency of the motor is estimated taking account of the motor and the motor drive related losses. The proposed control achieves 1.5% higher efficiency due to the utilization of gallium nitride (GaN) switching devices and the lower rms phase current in high switching frequency operation.