Electric-Field Coupled Power Transfer System Based on Single Switch DC-DC Converter

In order to solve the problem of high frequency inversion and rectification in Electric-filed Coupled Power Transfer (ECPT), this paper studies a electric-field coupled power transfer system based on single switch DC-DC converter at MHz. This system has only four working modes under high-frequency working conditions. The circuit design of this system is based on the Buck-Boost circuit. A pair of coupling capacitors are added to the original circuit, and the original single inductor is transformed into the inductor L
_in
on the energy transmitting side and the inductor L
_out
on the energy receiving side. The application of a single switching transistor simplifies the circuit control and reduces the switching loss of the circuit, thereby achieving an efficient ECPT system. This paper analyzes the working process of the system at high frequency, and gives the design method of the system parameters in detail. Finally, a prototype with pF coupling capacitor at 1.5MHz is built to verify the effectiveness of the system.