A Reconfigurable LCC-P/S Compensated Three-Phase Wireless Charging Topology with Constant Current and Constant Voltage Output

A practical wireless charging system should be capable of both constant current (CC) charging and constant voltage (CV) charging for batteries. As a solution, reconfigurable topologies have been widely studied for single-phase systems. This paper proposes a novel reconfigurable topology for three-phase wireless charging systems without extra capacitors or inductors that previous single-phase designs usually have. In the proposed topology, an LCC compensation network of the transmitter and the parallel (P) / series (S) capacitors of the reconfigurable receiver consist of the LCC-P/S topology for CC charging or CV charging respectively. The change of topology from LCC-P to LCC-S is realized by two 3-pole double-throw (3PDT) power relays. Relay operations have been optimized to minimize arc flashes to protect the relay contacts. A 1.8 kW three-phase unipolar-coil-based experimental prototype is built. The experimental results have verified CC and CV characteristics. Output current and voltage variances are less than 2% and 1.3% respectively. The maximum efficiency is 94.6% and 93.5% in CC mode and CV mode respectively.