Implementation of a Shunt-Series Compensator for Nonlinear and Voltage Sensitive Load

This paper presents the system analysis and circuit implementation of single-phase shunt-series compensator to improve voltage and current quality at the load side. The series compensator is adopted to compensate the voltage disturbance including voltage sag, swell, flicker and harmonics. The shunt compensator is used to supply the necessary active current to main the constant dc-link voltage of the inverter and to improve the power quality of utility source including the reactive current and harmonic current. The full-bridge inverters are used in the series and shunt compensator with the common dc-link. The full-bridge inverter has less voltage stress of power semiconductor compared with the voltage stress of switching devices in the half-bridge inverter. There is an active power flow between the series and shunt compensators to main the dc-link voltage constant when voltage disturbance is detected at the point of common coupling. The system analysis and operational principle of the adopted system is presented. Some experimental results of a scale-down prototype circuit are presented to verify the effectiveness and validity of the proposed control scheme