3E12 Series-Parallel Continuously Regulated Chopper for Auxiliary Power Supply of Electric Railway Vehicles(Electrical-Vehicle)

Abstract

The conventional Auxiliary Power Supply (APS) for railway vehicles has been directly connected to catenary through the LC filter. Hence, the switching devices of APS must have high breakdown voltage considering catenary voltage fluctuation. On the other hand, low voltage switching devices which have better characteristics are desirable from the point of view of low loss and capability of high frequency operation. Therefore, step-down converter is incorporated between the LC filter and the inverter to adopt catenary voltage fluctuation using low voltage switching devices. This paper proposes the series-parallel continuously regulated chopper which is a novel step-down converter. First, fundamental operation characteristics and output voltage control method of the proposed converter are introduced. After that, experimental results of fundamental characteristics are described and it shows that the experimental values are almost the same as theoretical values. The proposed chopper keeps controlling output voltage on the expected value without dramatically fluctuation in spite of input voltage fluctuation.