Control design and experimental investigation for a current sensorless STATCOM

The static synchronous compensator (STATCOM) is a voltage-sourced inverter (VSI) which can be used to regulate the load voltage through the reactive power compensation. This paper presents a novel control strategy for a current sensorless STATCOM. The system’s control, incorporating an AC and DC voltage regulator as well as an inverter output voltage calculator, are targeted to directly calculate the inverter output voltage to counteract the voltage drop across the inverter output filter based on the power balancing law. Experimental results are included to verify the proposed control scheme for both leading and lagging VAR compensation, along with changes between them.