Electric-Field Coupled Power Transfer System with Constant Current and Constant Voltage Output Based on Switchable Secondary Side of LCL-LLC/S Structure

In the practical application of electric-field coupled power transfer (EC-WPT) technology, the battery type load requires the power supply system to provide constant current or constant voltage output under load changes and the function of instant switching between the two output modes. This paper proposes an electric field-coupled power transfer system with constant current/constant voltage output based on LCL-LLC/S topology with switchable secondary side, and the system automatically enters the low power state when the battery is charged and removed. Firstly, the basic structure and switching strategy of the system are introduced, and the equivalent model of the system is set up. Then the principle of constant current/constant voltage and load adaptive is analyzed, and the parameter conditions and optimal switching point of the system are derived, and the parameter design method of the system is given. Finally, a simulation model is built to verify the feasibility and reliability of the proposed EC-WPT system's constant current/constant voltage output characteristics and its parameter design method.