2 - Power electronic devices

Abstract

The key component of power converters is the power semiconductor device, also called power electronic device. Different from the semiconductors used in the electronic field, power electronic devices generally have larger rated values of current and voltage. The power rating of the power electronic devices also covers a wide range, from several watts to several megawatts, targeting different applications. The power electronic devices can be classified into three types according to the controlling features, that is, uncontrolled devices, half-controlled devices, and fully controlled devices. The uncontrolled devices mainly refer to different types of power diodes. The half-controlled devices mainly refer to thyristors, in which the turn-on event is controllable while the turn-off is not. The fully controlled devices refer to the three-terminal semiconductors in which the control terminal can determine both the turn-on and turn-off states. The power MOSFET (metal-oxide-semiconductor field-effect transistor), IGBT (insulated gate bipolar transistor), GTO (gate-turn-off thyristor), and Power BJT (bipolar junction transistor) are all fully controlled devices. The power electronic devices are also key components in power electronic modeling and simulation, and they are exactly where the differences are from and where the challenges are raised compared the other electrical circuit simulations. In this chapter the commonly used power electronic devices including power diodes, thyristors, power BJT, power MOSFET, and IGBT are introduced. The physics structures and operating principle are described to help the readers to be familiar with those devices. Then the static characteristics and dynamic characteristics of these devices are presented to better understand the working mechanism of power electronics and their behaviors in the circuit and prepare the fundamentals to model these devices in real-time simulations.