Torque ripple and switching frequency reduction of interior permanent magnet brushless direct current motors using a novel control technique

Abstract

Although interior permanent magnet brushless direct current (IPMBLDC) motors have higher torque and power density compared to surface-mounted PMBLDC motors, the reluctance torque of IPMBLDC motors generates higher torque ripples. This study introduces a new current waveform as a reference to control the IPM motors while keeping the total developed torque constant. It also helps to considerably reduce the torque ripple of the motors. The experimental results show that this method significantly reduces the damaging impact of the reluctance torque ripple without complicating computations or changing the stator and rotor structures of the motor. Additionally, the switching frequency and consequently switching losses are reduced using the proposed technique.