Prof Chris Mi, Fellow IEEE and Chair of Department of Electrical and Computer Engineering from San Diego State University, presented to EE students this Friday on Feb 24, 2017, a talk with the topic of High Efficiency Wireless EV Charging Using Wireless Power Transfer.
Prof Chris Mi, IEEE Fellow from San Diego State University was delivering a talk to EE students on Feb 24,2017.
He focused on wireless power transfer technology that offered significant improvement in convenience and electric safety for EV and PHEVcharging in the first part of the presentation. His research group aims at novel designs that considerably reduces size and cost while increase coupling coefficient and system efficiency. Distributed capacitors instead of lumped components were proposed. A double sided LCC resonant converter topology for the resonant stage was adopted to further enhance system efficiency. Laboratory prototypes had been built and 22kW power transfer had achieved over 200mm distance,93.5% system efficiency (97% DC-DC efficiency), and alignment tolerance of up to 300mm.
In the second part of the presentation, Prof Mi discussed capacitive power transfer (CPT) for EV charging applications. It had been an established myth that good efficiency and stability of control was only possible in capacitive power transfer (CPT) at low power levels (in the tens of watts) and with low transfer distances (in the millimeter range).
Prof Mi and his team had shown it was possible to achieve excellent efficiencies at the power level and distance applicable to EV charging, breaking the established myth, enabling a paradigm change on EV charging, and making low cost wireless power transfer from science fiction to reality. A double-sided LCLC-compensated topology and its design process were then proposed. According to Dr Mi, A 2.4kW CPT system was designed with four 610mm × 610mm copper plates and an air gap distance of 150mm. The experimental prototype reaches a dc-dc efficiency of 90.8% at 2.4kW output power. At 300mm misalignment case, the output power drops to 2.1kW with 90.7% efficiency. With a 300mm air gap distance, the output power drops to 1.6kW with 89.1% efficiency.
Prof Mi is a fellow of IEEE, Professor and Chair of the Department of Electrical and Computer Engineering, and the Director of the US DOE funded GATE Center for Electric Drive Transportation at San Diego State University, San Diego, California, USA. He was previously a professor at the University of Michigan, Dearborn from 2001 to 2015. He received the B.S. and M.S. degrees from Northwestern Polytechnical University, Xi’an, China, and the Ph.D. degree from the University of Toronto, Toronto, Canada, all in electrical engineering. Previously he was an Electrical Engineer with General Electric Canada Inc. He was the President and the Chief Technical Officer of 1Power Solutions, Inc. from 2008 to 2011. He is the Co-Founder of Gannon Motors and Controls LLC and Mia Motors, Inc. His research interests are in electric and hybrid vehicles. He has taught tutorials and seminars on the subject of HEVs/PHEVs for the Society of Automotive Engineers (SAE), the IEEE, workshops sponsored by the National Science Foundation (NSF), and the National Society of Professional Engineers. He has delivered courses to major automotive OEMs and suppliers, including GM, Ford, Chrysler, Honda, Hyundai, Tyco Electronics, A&D Technology, Johnson Controls, Quantum Technology, Delphi, and the European Ph.D School.
