A Novel Reconfigurable Wireless Charging System Achieving Constant Current and Constant Voltage Conversion by a Single Secondary-Side Switch

The wireless charging process for lithium batteries involves two key phases: constant current (CC) mode and constant voltage (CV) mode. This letter introduces a novel method for topology reconfiguration, simplifying the CC and CV conversion with the control of a single secondary-side switch. The system leverages a three-coil structure for CC output and employs a single switch to reconstruct the two secondary coils, achieving CV output. This approach stands out from previous solutions that required primary control and multiple switches. Using a single switch on the secondary side significantly simplifies the system control and eliminates the necessity for communication with the primary side. These improvements contribute to heightened system reliability. To validate this concept, a prototype with a maximum output of 1.2 kW was developed and tested.