Development of an innovative repetitive impulse voltage generator [News from Japan]

It is well recognized that our modern world would not be so developed without the advancement of power electronics. Almost all electrical and electronic machines use various power electronic technologies. Among many power electronic devices or systems, the contribution of a converter-inverter system is most significant. Here, converters are the devices that convert AC voltages to DC voltages, and inverters convert them in the opposite way. Electric power conversion devices that use both converters and inverters are often called converters, although they are usually called inverters in Japan. We can say that all electronic devices require converters. In addition, converters can significantly increase the efficiency of a driving system using electric motors. A typical example, Tokyo Metro Co. Ltd. and Mitsubishi Electric Corporation, both in Tokyo, announced that they achieved the reduction of electric power consumption of commuter subway trains by 38.6% by introducing SiC-based pulse-wave-modulation converters in 2012 [1].