A Transistorized DC Commutatorless Series Motor Drive with Reduced Torque Ripple for Electrified Vehicle Applications

This paper presents a Transistorized DC Commutatorless Series Motor Drive (CLSM) which will find applications for electrified vehicles (EV) for its natural inverse torque-speed characteristics with low torque ripples. The basic configuration of the solid-state power electronic converter and the machine is presented first with its operation explained. Mathematical model of the drive is presented next, followed by the developed phasor diagram. The results of the numerical simulation are presented later. The conclusions are presented at the end. The simulation results prove that the proposed drive will be a strong contender for traction applications because of its natural ‘series’ type of torque-speed, current-speed and torque-current characteristics, lower low-frequency component of torque ripples, lower ‘dv/dt’ stress to machine armature windings, simplicity of drive control and operability from a low-voltage DC battery pack.