**A Review of Dynamic Wireless Power Transfer for In‐ Motion Electric Vehicles**

Kai Song, Kim Ean Koh, Chunbo Zhu, Jinhai Jiang, Chao Wang and Xiaoliang Huang

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/64331

#### **Abstract**

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Dynamic wireless power transfer system (DWPT) in urban area ensures an uninterrupt‐ ed power supply for electric vehicles (EVs), extending or even providing an infinite driving range with significantly reduced battery capacity. The underground power supply network also saves more space and hence is important in urban areas. It must be noted that the railways have become an indispensable form of public transportation to reduce pollution and traffic congestion. In recent years, there has been a consistent increase in the number of high‐speed railways in major cities of China, thereby improving accessi‐ bility. Wireless power transfer for train is safer and more robust when compared with conductive power transfer through pantograph mounted on the trains. Direct contact is subject to wear and tear; in particular, the average speed of modern trains has been increasing. When the pressure of pantograph is not sufficient, arcs, variations of the current, and even interruption in power supply may occur. This chapter provides a review of the latest research and development of dynamic wireless power transfer for urban EV and electric train (ET). The following key technology issues have been discussed: (1) power rails and pickups, (2) segmentations and power supply schemes, (3) circuit topologies and dynamic impedance matching, (4) control strategies, and (5) electromagnetic interference.

**Keywords:** dynamic wireless power transfer, magnetic coupler, circuit topologies, control strategies, electromagnetic interference

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
