Oak Ridge National Laboratory Wireless Power Transfer Development for Sustainable Campus Initiative

Wireless power transfer (WPT) is a convenient, safe, and autonomous means for electric and plug-in hybrid electric vehicle charging that has seen rapid growth in recent years for stationary applications. WPT does not require bulky contacts, plugs, and wires, is not affected by dirt or weather conditions, and is as efficient as conventional charging systems. This study summarizes some of the recent Sustainable Campus Initiative activities of Oak Ridge National Laboratory (ORNL) in WPT charging of an on-campus vehicle (a Toyota Prius plug-in hybrid electric vehicle). Laboratory development of the WPT coils, high-frequency power inverter, and overall systems integration are discussed. Results cover the coil performance testing at different operating frequencies, airgaps, and misalignments. Some of the experimental results of insertion loss due to roadway surfacing materials in the air-gap are presented. Experimental lessons learned are also covered in this study.