Development of low-cost drive system of a small-size electric vehicles

This paper develops the low-cost drive system of the small-size electric vehicles (EVs) driven by the brushed dc motor. The power circuit for driving the dc motor is designed by considering both the cost and efficiency. Some MOSFET and diodes at the power converter are connected in parallel for reducing the conduction loss. In order to change smoothly the rotating direction of dc motor, an operating sequence for both the field current and the armature voltage according to the accelerator pedal angle is suggested. Through the simulation studies and experimental results with the low-cost 8-bit AVR, the performances of the proposed methods are verified.