A novel control scheme of propulsion motor for integrated powertrain of electric bus

An integrated powertrain with electric motor and multi-gearbox is a suitable choice for the propulsion of electric bus due to its low cost and improved performance. But it also causes some problems in motor control without damping components. This paper presents a motor control scheme for shifting. Based on detailed analysis of shifting process, requirements on the motor are provided and the whole shifting control process is divided into four phases. Then the motor control scheme is developed, sliding mode-based direct torque control with space vector modulation (DTC-SVM) is adopted to ensure fast response and good system robustness. Moreover, the switch between torque loop and speed loop is added to the algorithm for good shift quality. Simulation models are developed to verify the effectiveness of the proposed control scheme. The results show that the control system enjoys a short shift time and negligible shock with small speed error. Therefore, the proposed control scheme is suitable for the direct coupled integrated powertrain applied to electric bus.