Slides - 120 kW High-Power Wireless Charging System Development

Abstract- Electric vehicles have the potential to significantly reduce the dependency on imported oil, enhance national energy security, and reduce the greenhouse gas emissions. However, there are two major drawbacks against the widespread commercialization. Limited range and long battery charging times remain to be the critical challenges to mass electrification of our transportation sector. While the vehicles with higher energy battery packs can mitigate the range anxiety problem, it would take very long to recharge these vehicles; namely 83, 30, or 15 hours with the conventional 1.2, 3.3, or 6.6 kW chargers, respectively. While DC fast charging can enable charging power levels for less than 100 kW and reduces the charge times to less than an hour, the connectors, plugs, and cables would be difficult to handle, and conductive charging would be cumbersome with all the heavy and bulkier cables. Therefore, inductive wireless charging systems can be a viable option for the high-power and fast charging systems for EVs. Wireless power transfer is a safe, flexible, and a convenient form of EV battery charging without requiring manual connection of charge cables, it has inherent isolation from the grid to the vehicle, it can run in all-weather conditions, and can also automate the charging process of the EVs without user involvement. This webinar focuses on a 120 kW wireless power transfer system developed at the Oak Ridge National Laboratory. This system can charge a 100 kWh battery pack from 20 to 80 percent state-of-charge in 30 minutes, which can bring the EV charging process closer to the fuel pumps at the gas stations. The webinar introduces the state-of-the art literature review on high-power wireless charging systems and details the design and development of the power electronics and electromagnetic coupling coils with their finite element analysis based models. Design details and parameters of the system will be covered along with the experimental performance analysis of the system including the stage-by-stage power flow and efficiency of the system.