A large-capacity capacitor simulator using a bi-directional chopper and PWM rectifier

This paper proposes a large-capacity capacitor simulator consisting of a chemical capacitor and three-leg converter. One of three legs performs a bi-directional chopper. The others are used for a PWM rectifier. In the charging mode the most of the power stored in the chemical capacitor is injected to the utility through the PWM rectifier. In the discharging mode the power is supplied to the chemical capacitor side from the utility through the PWM rectifier. Thus the proposed simulator performs a large-capacity capacitor. The basic principle of the proposed simulator is discussed in detail. A prototype experimental model is constructed and tested. Experimental results demonstrate the validity and excellent practicability of the proposed simulator.