Power Converion And Management For Space Station Power System

With the development of manned spacecraft technology, multi-module combined space station(MMCSS) will be greatly adopted in the large-scale space station. Compared with the early single-module space station, there are some characteristics in the MMCSS power supply system: independent power supply of each module, easy to be blocked of the solar panels, etc. Thus, a reliable and redundant power supply system is required to maintain the power generation normally.First of all, the schemes of the MMCSS redundant power supply system are researched in details. The grid-connected redundant power supply system is adopted for its high expansibility, which is composed of a common DC bus and many bidirectional power converter cells. The structure and design keys are analyzed.Then, in order to solve the problem of MOSFET's body diode reverse current and direct-through in the conventional bidirectional Buck-Boost converters, three novel bidirectional Buck-Boost converters with coupled inductor are researched. The operation principles of each converter are analyzed in details, the design methods of key elements are researched and the experimental results are given to verify the analysis. For the high power density and reliability, the bidirectional Buck-Boost converter with positive coupled inductor is adopted as the bidirectional power converter cell in the MMCSS redundant power supply system.Finaly, a 6kW protype of bidirectional Buck-Boost converter with positive coupled inductor is built up, and the design methods of key eliments are presented. The experimental results of power converion and management are given. The feasibility and validity of the bidirectional Buck-Boost converter applied for MMCSS redundant power supply system are proved.