Control of Novel Active Capacitor System for Wireless Power Transmission

In recent years, with the spread of electric vehicle equipped with a large battery, the development of charging systems is also progressing. One of them is wireless power transmission (WPT). Generally, efficiency of WPT can be improved by incorporating a capacitor in the circuit to form a resonant circuit. However, the optimum capacitance varies when parameters of transformer vary. In this research, a novel active capacitor (AC) system is proposed. It consists of single phase inverter and can operates as a virtual capacitor with variable capacitance. The configuration and control method are explained and experimental result by a basic WPT testing system is presented.