A power electronic transformer based on a 4-plate compact capacitive coupler

This paper proposes a power electronic transformer based on a capacitive coupler. The coupler consists of four plates which are parallel-placed very closely. And there is a dielectric layer between each two plates to increase the capacitance value. The two plates on the same side are placed close to each other to maintain a large capacitance. The system topology is symmetrical to achieve bi-directional power transfer as both sides are composed of a full bridge inverter and a LCL circuit. The LCL circuit is used for filtering waves and forming resonance with the coupler. The coupler is modeled to simplify the analysis of the circuit. The whole system is verified by theory and simulation.