Abstract Capacitive power transfer is a rapidly developing technology. It is more economical, reliable, and safer than inductive power transfer, and can be widely used in environments that have many metal structures. Since capacitive power transfer uses high frequency electric field to transfer power, there are high frequency voltages stressed on coupled plates. Also, voltages will be induced on the surface of the applications such as electric vehicle, it is a serious problem for safety concern. To solve this problem, this paper proposes a static power transmission system optimization strategy based on capacitive power transfer system to reduce the voltage on the shell of a car. The CLL compensation structure is used and optimized to resonant system. A 1.3kW output power system with the optimization strategy is built to verify the analysis results. The efficiency of the prototype reaches 87.7%. With the optimization method, the effective voltage of the experiment shell is 3.88V which agrees with the calculation results.
Guo Limou,Luo Bo,Mai Ruikun. Voltage Optimization Method for Wireless Charging of Electric Vehicles Based on Capacitive Power Transfer[J]. Transactions of China Electrotechnical Society, 2020, 35(zk1): 19-27.
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2020, Vol. 35 
