Power electronics

Abstract

Power electronics is the key technology when it comes to accurately controlling the flow of electrical energy to match a source with the requirements of a load. It is only when an electrical load is supplied with the precise amount of electrical energy needed to meet the current requirement - e. g. in brightness control of lighting, rotation control of an electric motor, acceleration/braking control of trains - that minimum energy consumption and optimum performance of the load can be achieved. In order to minimise power loss when controlling the flow of electrical energy, it is crucial to select the appropriate power semiconductor devices to give the proper frequency and switching performance. At high switching frequencies, like those applied in power supplies for PCs (typically higher than 100 kHz), fast electronicallytriggered switches such as power MOSFETs (metal-oxide- semiconductor field-effect transistor) are required. By contrast, electronically-controlled switches that have low conduction losses, such as IGBTs (insulated-gate bipolar transistor), are needed to control the rotation speed of electric motors (which have typical switching frequencies lower than 10 kHz). © 2009 Springer Berlin Heidelberg.