Research And Development On Control System Of The Switched Reluctance Motor Applied In Electric Vehicle

Motor drive is the key technology of new energy vehicles, especially electric vehicles, and in the current research field, it is one of two main directions of the EV industry. In this dissertation, the applied technology of motor drive technology is studied and the object is an 8/6 structure Switched Reluctance Motor (SRM). A new control system for this kind of motor is devised in order to make the motor work in time sharing mode as a generator and electric motor. The main contents of this thesis are summarized as follows:First, according to the structural characteristics and principles of SRM, the mathematical model of SRM is build and the work principle of SRM is classified as a generator and electric motor. On this basis, a bidirectional control system for SRM is presented used in EVs and then the control strategy is determined. Consequently, for EVs, both the states of normal driving requirements and the energy feedback of braking or sliding are achieved.Then, on the basis of the control strategy and the the control methods, the overall scheme of the control system for SRM is devised, including the design of hardware and the compiling and debugging of software . H-bridge converter for SRM is built,using chopped current control and voltage chopping control as the major control chip,and then the drive circuit,the signal acquisition circuit and the protection circuit are devised. Corresponding to the different energy flow processes under the state of generating and motor-operated, the same set of hardware peripherals circuits are used, but in software part different methods are chosen to realize the time sharing control.Finally, experiments have been done on this SRM bidirectional control prototype system, and based on the experiments under the state of generating and electric motor, in order to validate the drive system in this article. The result shows that the prototype system has stable operation and good properties, and the practical exploration is provided for braking energy recovery of electric vehicles both in theory and practice.