Research on a New Motor Drive Control System for Electric Transit Bus

To eliminate the deficiencies in the conventional drive control system of direct current (DC) motor for electric vehicle, we design a new permanent magnetic direct current (PMDC) motor with the enhanced exciting windings, namely, enhanced magnetism motor and develop its drive control system for electric transit bus. It can obtain enhanced torque with enhancing magnetism in low speed and enhanced speed with weakening magnetism in high speed automatically. On the basis of data and graph of experiments, we analyze its control theory and characteristics. Contrasting the enhanced magnetism motor to conventional DC motor with exciting windings in series, the enhanced magnetism motor as great advantages on characteristics of control way, configuration of controller and regenerative braking. Heat assessing experiment shows that switched loss is main part of power loss when IGBT switched in high frequency and it will affect the controller characteristics. Experiments of vehicle running show that the drive control system´s anti-jamming ability is strong and the regulated performance is fast and smooth, and it´s characteristic of enhanced torque with enhancing magnetism in low speed and enhanced speed with weakening magnetism in high speed can meet the electric transit bus´s demand of power characteristics very well