Novel Design Approach of Wireless Chargers for Electric Vehicles

Wireless charging of electric vehicle batteries is a modern technology of real interest to replace the classical solutions with plugged-in chargers with their mechanical and electrical hazards related to cables and power connectors. Although the technical solution of near-field contactless power transfer is well known, and several achievements are described in the technical literature, the issues of charging time, power transfer efficiency, system stability in real-world conditions and EMC-related problems remain of wider interest. In such a context, this paper presents a novel design approach of wireless power transfer systems with tight coupling for electric vehicles to get a reasonable transferred power with high efficiency and with less sensibility to parameter deviations as in real practice. It also does not require a supplying inverter with variable output frequency. The study is focused on design optimization of magnetically coupled resonators in series-derivation topology. Our theoretical analysis is proven by relevant experimental results.