On the analysis and control of a three-switch three-phase inverter-fed brushless DC motor drive

Purpose - This study seeks to examine the analysis and control of a three-switch three-phase inverter (TSTPI)-fed brushless DC motor (BDCM) as well as the comparison of its performance with those yielded by six-switch three-phase inverter (SSTPI)-fed BDCM drives. Design/methodology/approach - The analysis of the six operating sequences of the TSTPI-fed BDCM drive followed by the implementation of a dedicated self-control strategy in such a drive and the comparison of its performance with those given by an SSTPI-fed BDCM drive. Findings - The dedicated self-control strategy required the integration of a torque loop in the implementation scheme in order to reduce torque ripple amplitude during sequence-to-sequence commutations. It has been shown that the TSTPI-fed BDCM offers high performances which are almost the same as those of the SSTPI-fed BDCM. Research limitations/implications - This work should be extended by building a test bench made up of a TSTPI-fed BDCM and the comparison between simulation results and experimental ones. Practical implications - A 50 per cent reduction in cost and compactness, and a 50 per cent increase in reliability make the TSTPI an interesting candidate especially in large-scale production applications such as the automotive industries. Originality/value - The paper proposes an approach to improve the cost-effectiveness and the volume-compactness of BDCM drives which represents a crucial challenge in electric and hybrid propulsion systems. It is the best solution compared with the conventional SSTPI and the four-switch three-phase inverter.