A New Design for Tapped-Inductor Transmitter With Multiple Concurrent Resonant Frequency Outputs for Wireless Power Transfer

This article proposes a wireless power transfer (WPT) system that can deliver power to multiple receivers with additional resonant frequencies and concurrent frequencies. It employs a multiple frequencies H-bridge inverter, which can control the frequencies and the output powers of the receivers independently. Compared with the typical multiple-frequency and multiple-receiver WPT system, the proposed WPT system can power a considerable number of receivers simultaneously or independently. Additional resonant frequencies and concurrent frequencies can be obtained by the original transmitter without any physical changes. The resonant frequencies transmission, additional resonant frequencies transmission, and concurrent frequencies transmission are investigated analytically in detail. To validate the proposed design performance, a tapped-inductor transmitter, along with three receivers designed at a frequency range from 50 to 200 kHz have been fabricated. At 30-mm separation, the system is able to deliver a maximum power of 240.8 W and a maximum efficiency of 92.36% at 50 kHz and 200 kHz, respectively.