一、前言 近年来,美国、日本等工业发达国家对电力电子技术的发展和应用都相当重视,把它视为“第二次电子革命”。日本历来对电力电子器件的发展给予支持,GTO、功率MOSFET、IGBT等器件不断得到改进,水平提高很快,在SIT和SITH方面更是占据领先地位。东芝、三菱、日立、NEC等大公司也相当重视 I. Introduction In recent years, the developed countries such as the United States and Japan have attached great importance to the development and application of power electronic technology and regarded it as the “second electronic revolution.” Japan has always been to support the development of power electronics, GTO, power MOSFET, IGBT and other devices continue to be improved, the level of rapid increase in the SIT and SITH is a leading position. Toshiba, Mitsubishi, Hitachi, NEC and other large companies also attach great importance