A new power converter topology for PM brushless DC motor drives

A new converter topology for permanent magnet brushless DC (PMBDC) motors is proposed in this paper. It has the advantages of minimum number of power switching devices, equal voltage rating for all the switching devices and variable DC link voltage for application to the motor. The operational characteristics of this converter-driven PMBDC drive are derived for four-quadrant performance. The feasibility of the proposed converter topology for the four-quadrant PMBDC motor drive system is validated by extensive dynamic simulation of the motor drive system. The simulations verify the advantages of the drive in low speed operation with lower switching ripple and hence lower torque ripple. The merits and demerits of the converter are derived. A comparison of the proposed converter with the 3 phase full-wave converter is given