A study of optimization for efficiency and power control in an electromagnetic WPT system

In this study, the power efficiency in a WPT system is measured under the condition of various transmission distances and the optimum control of the parameters is considered in the system from the results. The change of the resonance frequencies according to the change of coupling coefficients improve the power transmission efficiencies of the system compared to the case of the fixed resonance frequency. In addition, we reveal the trade-off between the magnitude of the output power and the power efficiency in terms of the resonance frequency. From our analysis, the trade-off resonance frequency is derived at various transmission distances by numerical simulation.