On the front-end converter and its control for a battery powered switched-reluctance motor drive

This paper presents the development of a front-end converter and its control for a battery powered switched-reluctance motor (SRM) drive. In motoring mode, the converter is operated as a dc-dc boost converter to establish dynamically boostable and well-regulated dc-link voltage from battery. The digital control schemes of boost converter and motor drive are implemented using a common digital signal processor. A proper voltage boosting feedback controller is designed to effectively enhance the SRM winding current and speed dynamic responses. Then the robust speed control performance is achieved by the proposed control scheme consisting of robust disturbance feedforward control and variable-structure system control. In addition, an effective regenerative braking control scheme for SRM is developed. In idle charging mode, the proposed front-end converter is arranged to act as a buck-type switch-mode rectifier (SMR) for charging the battery with good line power quality. Four diodes embedded in the SRM converter and the two motor phase winding inductances are employed to form the necessary constituted components of the SMR. The circuit and controller designs are presented, and good charging power conditioning performance is demonstrated experimentally.