LC-CLC compensation topology for capacitive power transfer system to improve misalignment performance

To improve the coupler misalignment performance, this study proposes an LC-CLC compensation topology for high-power and long-distance capacitive power transfer system. The LC circuit in the transmitter and the CLC circuit in the receiver are adopted as the resonant tank for the capacitive coupler. The fundamental harmonics approximation method is employed to analyse the system working principle. Considering the misalignment of coupler, the characteristic of output power is provided against the variation of coupler capacitance. A 1 kW CPT system with 150 mm transfer distance is set up to validate the proposed compensation circuit under various misalignment conditions. The experiment results show that the system can transfer 1009 W output power with 90.56% DC-DC efficiency at 150 mm transfer distance when the coupler is well aligned. When the misalignment is 325 mm, the variation of the output power is only 10.6% in X-direction and 15.2% in Y-direction. The proposed system can achieve high anti-misalignment performance.