Analysis of Wireless Power Transfer for Adjustable Power Distribution among Multiple Receivers

In a multiple-receiver wireless power transfer system, most of the power tends to be transferred to a receiver close to a transmitter. Therefore, it is highly desirable to find a way of providing the required amount of power to each receiver, as well as to improve the overall power transfer efficiency. In this letter, we investigate an impedance matching method of providing adjustable power distribution among receivers while preserving a high overall power transfer efficiency using coupled mode theory and circuit model. We also derive an optimal matching condition and the upper bound of the overall power transfer efficiency, in order to assess the performance of the proposed method. Finally, we perform circuit-level simulations to validate the accuracy of our analysis and the effectiveness of the proposed method.