Parallel Control Technology Research Of 300km/h EMU Auxiliary Inverter

With the rapid development of high-speed railway, the EMU becomes more and more important in track transport vehicle. As an important part of EMU, the liability of the auxiliary inverter is essential to the operation of the whole vehicle. In order to increase the liability of vehicle auxiliary power system, an auxiliary inverter parallel scheme is proposed in the paper to increase the whole capacity and stability of EMU power system.Firstly, according to the EMU auxiliary inverter technology indicators, a single auxiliary inverter has been designed, including the main circuit design and control circuit design.Secondly, on basis of parallel equivalent circuit of inverter, the paper analyzes the principle of parallel inverter system and develops mathematical models about it. Circulating current characteristics of parallel system, distribution control of distortion power, and characteristics about closed loop regulation of voltage are also proposed, which has laid a theoretical basis for the system design and control strategy of follow-up sections.Thirdly, according to the characters of vehicle auxiliary power system, several popular inverter parallel control strategies are analyzed, advantages and disadvantages of every strategy for vehicle are get in the paper. Then an advanced strategy from master-slave strategy is proposed in the paper. The strategy has a spare main inverter. When the main inverter is abnormal, the spare main inverter undertakes the main inverter's work. The strategy carries out every inverter model's output phase synchronous with one synchronous pulse and achieves output voltage stable, output current-sharing of every inverter model by output voltage instantaneous feedback dual-loop control and current -sharing control.Finally, simulation research of a single auxiliary inverter as well as parallel systems have been carried out by using MATLAB7.0 simulation software to verify the rationality of a single auxiliary inverter design as well as the feasibility of this article proposes parallel control strategy, which is a reference to the EMU auxiliary inverter.