Implementation of a motor control system for electric bus based on DSP

Motor control system may be the most important part of electric vehicles. To implement the control strategies, a lot of practical problems need to be taken into account. In this paper, an induction motor control system for electric bus is developed based on digital signal processor (DSP). The control strategy is based on field-oriented control and space vector pulse width modulation. Over-modulation, field weakening control, PI controller and fault diagnosis are also applied in this DSP algorithm. As a practical product running on a real electric bus with an 100 kW induction motor, communication with vehicle control unit (VCU) by controller area network (CAN bus), control system safety and PC software designed for experiment at lab are also discussed. The transient and steady-state performances of this motor control system are analyzed by experiments. Its performance is satisfactory when applied to the real electric bus.