A Closely Coupled and Scalable High-Power Modular Inductive Charging System for Vehicles

For a high-power inductive charging solution that can be used on all types of vehicles, careful consideration must be made in all steps of the design process, including system architecture, coil geometry, and communications. Extensive studies on the effects of human exposure to electromagnetic fields (EMF) have identified recommended guidelines for electromagnetic limits in regions where humans or other living objects may frequent. Commercial wireless low power chargers today operating at 85 kHz and up to 11 kW are capable of meeting international EMF standards such as IEEE C95.1-2019. In this article, we address high-power wireless chargers designed for electrified light and heavy-duty vehicles such as buses and trucks that accept charging in hundreds of kilowatts. Laboratory studies of a modular 50-75-kW coupler confirm that leakage fields from one such module will meet U.S. and International EMF limits at the vehicle perimeter and beyond. In particular, a cluster of four such couplers operating at 65 kW each will not exceed 27~\mu \text{T} adjacent to the vehicle, decaying at 1/ \text{r}^{3} or faster. The experimental results confirm simulation and show that fringing fields meet published standards in the vehicle cabin and beyond its perimeter when operating at 260 kW.