Global Sensitivity Analysis of Wireless Power Transfer System in Domino Structure

This paper proposes a global sensitivity analysis method of a wireless power transfer (WPT) system in domino structure. The sensitivity of system characteristics to capacitor deviations is studied to identify sensitive parameters that cause significant uncertainty in the output. The effect of capacitor deviations on output current, power transfer efficiency, and power factor is comprehensively investigated. Interactions between capacitors are considered, and the main effect index S and the total effect index ST are calculated by Sobol' method. Its results indicate that the output current, power factor, and efficiency are slightly affected by the deviation of the capacitor in series with the receiving coil. Interaction between capacitors has a significant effect on the output current and power factor. Finally, the experimental setups of the 3-coil and 4-coil WPT systems are built. The experimental results show that when the resonant capacitor on the receiving side is varied within ±10%, the fluctuation of the output current is less than 1.5%, the maximum variation in efficiency is less than 2%, and the power factor remains almost above 0.9. The validity of the proposed global sensitivity analysis method is verified.