Optimum load of WPT system analyzed by S-parameters

In this paper, the transfer efficiency of WPT system is calculated by using S-parameters if a WPT system is equivalent to a 2-ports lossy network. The optimum source and load impedances are deduced from the conjugated matching conditions for the maximum transfer efficiency of WPT system. The approach is applied to analyze the effects of different transmitting/receiving elements, different load on the transfer efficiency of WPT system. It is found that the method is very general and practical to deal with different WPT systems because the S-parameter can be obtained easily by the measurement or by the numerical simulation.