A moving wireless power transfer system applicable to a stationary system

Solving a short mileage and a long charging time is indispensable to putting electrical vehicles (EVs) on the full-scale market. A moving wireless power transfer (WPT) system is one of the effective solutions, because it can feed electric power to moving EVs. This paper proposes a moving WPT system consisting of several stationary ground-side (primary) coils and a moving vehicle-side (secondary) coil. This system is characterized by the use of the common vehicle-side coil to both moving and stationary WPT situations. Theoretical analysis concludes that the moving WPT system resulting from a stationary WPT system is the same in equivalent circuit as the stationary system. The moving WPT system employs solenoid coils that are superior to circular coils in terms of misalignment and flux-distribution performance. A downscaled moving WPT system rated at 3 kW is designed, constructed, and tested to verify the principles of operation, and the capability of continuous power transfer.