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Dr. Aaron Scher, Oregon Institute of Technology, Gives Special Seminar on February 7

Dr. Aaron Scher, Oregon Institute of Technology, will give a special seminar for CURENT students and faculty on Friday, February 7 from 10:00 am to 11:00 am in MHK 124.

Presenters: Dr. Aaron Scher, Oregon Institute of Technology

Time: Friday, February 7, 10:00 AM - 11:00 AM EST

Location: Min H. Kao Building, Room 124

Title: Design method for resonant inductive power transfer systems using a resistor ladder prototype

Abstract: Wireless power transfer offers compelling advantages over ordinary power cables in terms of convenience, safety, and function. Tuned-resonant inductive power transfer (IPT) systems contain loosely coupled resonant coils to transfer power across air gaps via magnetic induction. The topic is well established, as resonant inductive coupling is rooted in classical electromagnetics and was developed for wireless power transfer by Nikola Tesla over a century ago. However, for many decades this technology lay dormant and was not widely adopted. More recently – thanks in part to advancements in wide bandgap power semiconductor devices – resonant inductive coupling has gained popularity as a practical solution for wireless charging for a range of applications like biomedical devices, consumer electronics, and electric vehicles (EVs).

This presentation discusses a design-friendly method for finding the optimum load resistance that maximizes the power efficiency of a tuned-resonant IPT system. Power efficiency is a standard figure of merit, as achieving higher efficiency generally leads to smaller and lighter systems, lower component stresses, and lower wasted energy. In the presented method, the equivalent AC circuit of the IPT system is transformed to match the topology of a reference ladder prototype. This simplifies the design problem, because the ladder prototype offers intuitive and accurate closed-form approximations for the optimum load resistance and maximum power efficiency. The process is graphical in the sense that manipulations and transformations are made directly on the circuit diagram. Compared to traditional circuit analysis, the ladder prototype approach does not entail complicated systems of equations or matrix manipulations. This talk is based on a recent conference paper presented at the 2019 IEEE PELS Workshop on Emerging Technologies: Wireless Power (WoW) in London, England. 

Bio: Dr. Aaron Scher holds a B.S. (2003) and M.S. (2005) in Electrical Engineering from Texas A&M University and a Ph.D. (2008) in Electrical Engineering from the University of Colorado at Boulder. His background is in RF/wireless systems and applied electromagnetics. As a graduate student he worked at Lockheed Martin Missiles and Fire Control in Dallas, TX and Southwest Research Institute in San Antonio, TX. After earning his Ph.D. he joined Space Systems/Loral in Palo Alto, CA and designed microwave waveguide filters and multiplexers for communication satellites. In 2012, he joined the Electrical Engineering and Renewable Energy (EERE) Department at The Oregon Institute of Technology’s Portland-Metro campus. Dr. Scher is focused on engineering education and engages undergraduate students in his current research on wireless power transfer. He is currently participating in the Higher Education Research Experience (HERE) program at Oak Ridge National Laboratory as a visiting faculty member in the Power Electronics and Electric Machinery Group. Dr. Scher is an amateur radio enthusiast, avid hiker, design thinker, and a member of IEEE and ASEE.