Reasearch On Starting Control For Doubly Salient Electro-magnetic Starter/Generator

The doubly salient electro-magnetic motor (DSEM) is widely used in aerospace, automotive and wind power generation area for its adjustable excitation, simple structure and high-speed operation as switched reluctance motor. It is also capable of carrying on two reverse operations ? starting and generating. Therefore, the research on DSEM starter/generator is of great significance. Firstly, this dissertation reviews the development of brushless starter/generator system and DESM. The background and the significance of the research project as well as the main contents of this dissertation are presented. Then, the characteristics of the DESM, such as the structure, magnetic properties, mathematical model, working principle over the operating range and the methods of excitation current control are described in detail.Secondly, in order to establish the nonlinear inductance model, an experimental test approach based on DESM back EMF is demonstrated. Based on the nonlinear inductance model, a doubly salient motor starting model is obtained, and the current chopping of different methods are simulated and compared. Different starting processes are also simulated including constant torque operation, constant power operation and their combination.Thirdly, the DSEM starter/generator starting torque ripple generation mechanism is analyzed. Then, the operation principle and the steady state of the split-capacitor in DC-link of the half-bridge converter are discussed comprehensively. Moreover, an optimized control strategy of the half-bridge converter is proposed for the DSEM drives, and some simulations verify the analysis.Finally, A digital experimental test platform for DSEM starter/generator is built and an real-time monitoring software is developed based on LabVIEW to control of the operational status of the crew. The experiment results validate the theory and simulation analysis.