Distributed Auxiliary Inverter of Urban Rail Train—The Voltage and Current Control Strategy Under Complicated Load Condition

With increasingly prominent role of rail transit in the entire urban transport system, an auxiliary inverter is used increasingly. The complicated and fluctuating load condition of the auxiliary inverter implies special designs about structure and control strategy are necessary. For this purpose, a comprehensive control strategy is proposed. First of all, this paper proposes a structure that is capable of suppressing unbalanced voltage. Second, the control strategy based on the resonant controller is proposed, which can balance split capacitors voltage, is capable of suppressing the effect of unbalanced load and nonlinear load. This paper introduces the design method of the control system in detail. Then, this paper simulates the proposed comprehensive control strategy in MATLAB. Finally, experimental results are presented, which fully demonstrate the excellent performance of the comprehensive control strategy.