Research on Power Converters for High-Efficient and Light-Weight Auxiliary Power Supplies (APS) in Railway System

철도차량 보조전원장치의 고효율-경량화를 위한 전력변환회로 연구

  • Lee, Jae-Bum (Propulsion System Research Team, Korea Railroad Research Institute) ;
  • Cho, In-Ho (Propulsion System Research Team, Korea Railroad Research Institute)
  • Received : 2017.03.03
  • Accepted : 2017.04.04
  • Published : 2017.06.30


A recent trend of technical development in auxiliary-power-supplies (APS) is to replace 60Hz low frequency transformers with isolated type dc/dc converters. This paper introduces the technical trend in APS structures and proposes a power converter circuit suitable for high-efficient and light-weight APS. By utilizing the resonant converter, which achieves ZCS, to reduce switching losses, various types of APS structures (1-stage and 2-stage) are reviewed, and they are verified by simulation. The full-bridge resonant LLC converter is designed with a 1-stage power converting structure; the resonant converter topology is designed with a 2-stage power converting structure that has a pre-regulator converter to compensate for the wide input voltage range. Both a step-down converter and a step-up converter are designed and compared for the pre-regulator in the 2-stage structure. Operational characteristics are compared with simulation results and loss analyses are presented to proposes appropriate system structure and topologies.


Supported by : 한국철도기술연구원


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