Power electronics as key factor in generation, transmission, and usage of electric energy

Electrical energy exhibits highest flexibility in usage and controllability. However, electrical energy also raises high cost in generation and storage and is not sustainable in most cases for generation (burning coal or oil, or nuclear reactors). Advanced and sustainable generation employs power electronics in various circuits and power ranges. By today, large water power pump turbines with synchronous machines are speed controlled by converters even over 100 MW. State of the art is the modular multilevel conversion system with IGCTs or IGBTs along with antiparallel diodes. Wind power plants use permanent magnet synchronous machines again with full power converters. Photovoltaics become the field for application of SiC devices. HVDC transmission in classic style finds line commutated thyristors along with filter equipment that again uses power electronics for harmonics reduction. At less than about 1 GW we again see modular multilevel conversion circuits. Electric energy from Lithium-ion batteries as direct power source for individual mobility is used in zero-emission vehicles which rely on simple to complicated power electronics for realization of variable speed drives. Future applications can introduce Lithium-ion batteries not suited any more for mobile usage as local energy storage elements buffering power from renewable energy sources. Such applications require power electronics for energy conversion and easy control establishing an actually smart grid.