Abstract:
In the practical application of electric-field coupled wireless power transfer (EC-WPT) technology, some electrical equipment requires the system to have different constant output characteristics (constant current/constant voltage), that is, the system output voltage or output current is decoupled from the load. In addition, the system also needs to have the function of switching between constant current and constant voltage modes on demand. To meet this requirement, this paper proposes an EC-WPT system with constant current / constant voltage output characteristics based on LC-CLC resonant network, analyzes the characteristics of LC-CLC resonant network, deduces the realization conditions of constant current /constant voltage output characteristics and the calculation methods of constant current frequency and constant voltage frequency, gives the design method of system parameters, and analyzes the sensitivity of the system to the working frequency. Finally, the correctness and effectiveness of the constant current/constant voltage output characteristics and parameter design method of the EC-WPT system proposed in this paper are verified by simulation and experiments. The experimental results show that the proposed system achieves constant voltage output of 96 V and constant current output of 2 A under different load conditions with constant input voltage, and the maximum transmission efficiency is 87.83% and 88.17%, respectively.