Power Electronics | Rajashekara K. Bhat . Bose . Power Electronics The Electrical Engineering Handbook Ed. Richard C. Dorf Boca Raton CRC Press LLC 2000 30 Power Electronics Kaushik Rajashekara Delphi Energy Engine Management Systems Ashoka K. S. Bhat University of Victoria Bimal K. Bose University of Tennessee Power Semiconductor Devices Thyristor and Triac Gate Turn-Off Thyristor GTO ReverseConducting Thyristor RCT and Asymmetrical Silicon- Controlled Rectifier ASCR Power Transistor Power MOSFET Insulated-Gate Bipolar Transistor IGBT MOS Controlled Thyristor MCT Power Conversion AC-DC Converters Cycloconverters DC-to-AC Converters DC-DC Converters Power Supplies DC Power Supplies AC Power Supplies Special Power Supplies Converter Control of Machines Converter Control of DC Machines Converter Control of AC Machines Power Semiconductor Devices Kaushik Rajashekara The modern age of power electronics began with the introduction of thyristors in the late 1950s. Now there are several types of power devices available for high-power and high-frequency applications. The most notable power devices are gate turn-off thyristors power Darlington transistors power MOSFETs and insulated-gate bipolar transistors IGBTs . Power semiconductor devices are the most important functional elements in all power conversion applications. The power devices are mainly used as switches to convert power from one form to another. They are used in motor control systems uninterrupted power supplies high-voltage dc transmission power supplies induction heating and in many other power conversion applications. A review of the basic characteristics of these power devices is presented in this section. Thyristor and Triac The thyristor also called a silicon-controlled rectifier SCR is basically a four-layer three-junction pnpn device. It has three terminals anode cathode and gate. The device is turned on by applying a short pulse across the gate and cathode. Once the device turns on the .
