Recent development and future potential of the power static induction (SI) devices

Power static induction (SI) devices, such as the power static induction transistors (SITs) and SI thyristors, have been developed since the 1970s in Japan. The power SI devices include the normally-on/off type power SITs and the normally-on/off type power SI thyristors. By utilizing the light triggered/quenched SI thyristors as a key switching valve for a long-distance DC power transmission line, a high-efficiency DC transmission system will be realized. 60 kHz, 100 kW high efficiency (η>90%) inverters, 20 kHz, 5 kW resonant DC/DC converters, 20 kHz, 100 kW PWM inverters and active filters etc. have been developed by utilizing the 1200 V-300 A class SI thyristors. A 1.5 MHz, 100 W class quasi-resonant DC/DC converter was also realized by utilizing the 1200 V-5 A class ultra-high frequency and very low-loss SI thyristors. The application fields of the SI thyristors are rapidly being developed. The development and the future potential of the power SITs and SI thyristors is described and the performance of the practically applied equipment is reviewed