Soft-switching in aircraft power conversion systems

Two of the absolutely fundamental questions in current research and development of suitable power electronic inverters are the choice of circuit topology and the choice of power semiconductor devices. In particular, the circuit can be either “hard-switched” or “soft-switched”, and there are innumerable variants of both types: hence, the variant best suited to the associated application is to be determined. At present, the preferred semiconductor devices are likely to be either IGBTs or MCTs. This paper overviews the areas of aircraft power conversion application, giving emphasis to variable speed constant frequency power convertors. This is followed by a brief review of the present state-of-the-art inverter and power semiconductor device technology