Medium Voltage DC System Architectures

Direct Current (DC) transmission and distribution technologies have evolved in recent years. They offer superior efficiency, current carrying capacity, and response times as compared to conventional AC systems. Further, substantial advantages are their natural interface with many types of renewable energy resources, such as photovoltaic systems and battery energy storage systems at relatively high voltage, and compliance with consumer electronics at lower voltages, say, within a household environment. One of the core building blocks of DC-based technologies, especially at medium voltage levels, is power electronic systems technology. This cannot be emphasized enough as these units process, convert, and regulate all DC power and provide intelligence and sensing as electric power grids evolve.

These advantages have led to a rise in the utilization and applications of DC in modern power systems. This includes high voltage DC transmission systems, DC distribution grids, DC microgrids, electric vehicle charging infrastructure, and the maritime industry. However, there are still substantial challenges to the operation of these systems. Examples include a lack of standards for DC based power infrastructure and DC system protection.

This book presents the state of the art in medium voltage DC systems research and development, covering grid architecture, power converter design, transformers, control and protection for both traditional and mobile DC applications such as all-electric ships. This text, the first of its kind, provides essential information for researchers and research-oriented engineers working for academia, a manufacturer or utility, who wish to broaden or update their knowledge of medium voltage DC systems and associated equipment.

Brandon Grainger is an assistant professor and Eaton faculty fellow at the University of Pittsburgh, Swanson School of Engineering, USA. He is also associate director of the Energy GRID Institute and co-director of the Advanced Magnetics for Power and Energy Development (AMPED) consortium. His research interests include medium to high voltage power electronics, general power electronic converter design, wide bandgap semiconductor device utilization, solid-state transformers, and electric vehicle motor drives. He has worked for ABB, ANSYS Inc., Mitsubishi, and Siemens. He is a member of the IEEE Power Electronics Society and Industrial Electronics Society.

Rik W. De Doncker is a full professor at RWTH Aachen University, Germany. He is the director of the Institute for Power Electronics and Electrical Drives (ISEA). He also serves as director of the E.ON Energy Research Center of RWTH Aachen University and the BMBF German Federal Government Research Campus Flexible Electrical Networks. He is co-director of the RWTH Center for Wind Drives (CWD), the Center for Mobile Propulsion (CMP), and the Research Center Railways (RCR). Before joining RWTH he worked as Senior Scientist at General Electric CRD, Schenectady, NY and was CTO of Silicon Power Corporation, Malvern, PA. He is an IEEE fellow and member of several IEEE societies, and recipient of the 2013 IEEE Newell Power Electronics Technical Field Award, and the 2020 IEEE Medal in Power Engineering. His current research topics include electric vehicle propulsion systems, DC-to-DC converters, high power semiconductor devices, energy storage systems, and hybrid medium voltage switches and circuit breakers.