A Novel Dual-Receivers/Rectifier Reconstructed WPT System With Inherent CC to CV Transmission Characteristics and Reactive Power Minimization

In this article, an original dual-receivers/rectifier reconstructed three-coil wireless power transfer (WPT) topology for battery charging application is proposed. Proposed topology consists of a transmitting coil with inductor-capacitor-capacitor (LCC) compensation network, and two receiving coils utilizing series (S) compensation network connected with the rectifier part in parallel way. Only one receiving coil is coupled with primary transmitting coil and the other tries to avoid coupling with primary transmitting coil. Then the proposed topology has the ability of load-independent constant current output under a small equivalent load value and specific parameters resonant conditions. Simultaneously, with the increasing of equivalent load value, proposed topology can realize the automatic transmission of constant current to constant voltage charging mode. No wireless communication, relays and any closed-loop strategies are needed during the conversion process. In addition, zero reactive power input can also be achieved owing to the purely resistive input impedance and system transmission efficiency get benefit from the automatic power distribution of receiver segment. Finally, an experimental platform with 2A charging current and 72V charging voltage is built to verify the theoretical analysis for proposed WPT system.