In order to solve the problem of the electric vehicle (EV) charging amount fluctuation caused by the variation of driving speed during dynamic wireless charging, this paper proposes an EV dynamic wireless charging control method adapting to speed change. Firstly, a dynamic wireless charging model based on a long-track transmitting coil is established, and the expression of the charging power of each load under multi-load situation is obtained. Secondly, the influence of the EV charging number and maximum driving speed on the range of system parameters is studied. Subsequently, the method for determining the load resistance value according to the driving speed under a multi-EV charging condition is further discussed. Afterwards, a charging power control method adapting to the speed variation by load adjustment is proposed. By adjusting the equivalent load of the variable-speed charging EV, its speed variation range can reach 20~60 km/h, while the remaining EVs’ charging power fluctuation range can be kept within 10%~15%. Finally, the experimental prototype is built to verify the above-mentioned control method.

Wireless power transfer (WPT) systems for charging Electric Vehicles (EVs) have gained extensive attention due to their many advantages. However, human exposure to electromagnetic fields (EMFs) has become a serious concern in high-power cases. In this paper, shielding techniques, including magnetic, metallic, and resonant reactive current shields, are investigated. Finite element method software is used to evaluate and compare the shielding effectiveness, charger weight, and system performance. The results show that the resonant reactive current shielding has a low EMF level with reasonable system efficiency and acceptable charger weight. In addition, 5 kW with 15 cm air gap WPT chargers were built to validate the simulation results.

No abstract