Mitigation of Temporary and Sustained Power Quality Disturbances by UPQC

The unified power quality conditioner (UPQC) consists of s series active power filter (for conditioning voltage quality) and a shunt active power filter (for compensating current disturbances).This paper presents an improved scheme for controlling UPQC based on the instantaneous power theory. A model distribution network is simulated and analyzped that includes the different sources of temporary and sustained power quality disturbances. The main contribution of the paper are modeling of electric arc furnaces (as flicker producing loads) and simulation of single-phase short circuit faults (as source of voltage sags and swells), as well as the investigation of UPQC impact on damping of harmonic resonance. Based on the simulated results, the advantages and limitations of the proposed control scheme for UPQC are presented.

Keywords:

Harmonic , Imbalance , Sag , Swell , Flicker , Are Furnace and UPQC