Abstract: Introduction of more power electronic devices and non-linear loads pollutes the grid and create power quality problems. A unified power quality conditioner (UPQC) is Power electronic based device that mitigates simultaneously the voltage and current concerned Power Quality issues in the power distribution systems. In this paper presents a modified UPQC topology which consists of Series and shunt active filter is connected via common DC-link and a star connected transformer is added in the Shunt Active Power Filter for neutral current suppression and make the balanced system in compensation of three-phase system. In series controller Selective harmonic elimination based Series active filter is used for series compensation. And Id &IQ based control is used for shunt compensation. In the Dc link we add a solar based distribution to make utilize of renewable Energy for compensation and to meet energy Demand. The performance of modified UPQC topology using PI and fuzzy controller has been studied comparatively. Conventional PI controller can be compared with a fuzzy controller for better control, and thus improve the system performance. The effectiveness of the proposed system is verified using the MATLAB simulations.

Keywords: Distribution generation system, UPQC, Power quality issues. PI controller, Fuzzy logic controller, MATLAB.