A Dual-Frequency Compatible Wireless Power Transfer System With a Single Transmitter and Multiple Receivers

In many applications of wireless power transfer (WPT) systems, there are situations where the transmitter needs to supply power to receivers of different frequencies or powers. Therefore, it is very important to improve its compatibility and adaptability. In this paper, a dual-frequency compatible WPT system with a single transmitter and multiple receivers is proposed. The transmitter current contains two main frequency components obtained by current modulation and resonance compensation. The receivers of different frequencies pick up the corresponding components by frequency selective resonance. Therefore, decoupled transfer and independent control can be achieved. In this paper, a dual-frequency compensation topology is constructed and an adjustment method for receiver power decoupling control is proposed. Through theoretical and experimental analysis, the efficacy characteristics of the system have been evaluated, and its dual-frequency compatibility and power decoupling control capability have been verified. Compared with the single-frequency multiple-receiver system, this system can avoid the problems of mutual coupling: induced output power and system efficiency reduction, transmitter detuning, reactive power increase and inverter output capacity reduction.