摘要

Magnetic levitation train power supply systems, or Maglev, are most commonly powered by 330-V high-voltage direct current power systems. The power supply for maglev control system is used to provide a stable voltage to the suspension control circuit, which is the key part of Maglev trains. The suspension control power supply is typically a DC-DC converter with a high voltage input and multiple low voltage outputs. The traditional solutions typically lead to the following issues, such as uncontrolled duty ratio, poor cross-regulation capability, and low reliability. In order to solve these problems, a novel two-stage solution employing a double resonant tank LLC DC transformer (LLC-DCX) is proposed and developed in this paper. The proposed solution not only increases the overall conversion efficiency significantly because of the achieved soft-switching over the entire operation range, but also realizes the low input current ripple and high reliability owing to a uniform thermal distribution. A 210-W, 220-380-V input laboratory prototype with four outputs is fabricated and tested, and the experimental results are presented in this paper. The declared features of the proposed solution are well demonstrated by the experimental results.