A Multi-Function Voltage Source Inverter With Power Quality Compensation

The system analysis and circuit implementation of single-phase series-shunt compensator for nonlinear and voltage sensitive load is presented. The series compensator used in the adopted system compensates the abnormal voltage disturbance including voltage sag and swell at the load side. The shunt compensator supplies the necessary active current to keep the constant dc-link voltage of the adopted circuit and improves the power quality of ac source including the reactive current and harmonic current. The adopted series and shunt compensators are based on the neutral point clamp topology with the common dc-link. First the system analysis and operational principle of the adopted series-shunt compensator is presented. Some simulations and experimental results of a scale-down prototype circuit are presented to verify the effectiveness and validity of the proposed control scheme