Power electronics technology is a technology that uses high-power semiconductor switching devices to accomplish energy conversion, transmission and control. All kinds of power supply devices based on such devices and this technology are far superior to traditional rotary conversion devices in terms of both technical and economic indicators, and thus have made amazing development since the 1970s, and have completely replaced rotary converters in various application fields. In recent ten years, with the development of new devices and the improvement of performance, more high-performance power converter devices have appeared. This not only promotes the development of power electronics itself, but also affects the progress of semiconductor material technology, large-scale integrated circuit technology, automatic control technology, information transmission and processing technology and circuit topology technology. In short, power electronics technology is a technology with broad application prospects and developing in the ascendant.