Operation of unified power quality conditioner under different situations

Power Quality is an issue that is becoming increasingly important to electricity consumers at all levels of usage. The nonlinear characteristics of power electronic devices give rise to two important limitations; they generate harmonics and draw lagging current from the utility. In recent years unified power quality conditioner (UPQC) is being used as a universal active power conditioning device to compensate both harmonics as well as reactive power. In this work, UPQC has been modeled for both active and reactive power compensation using different control strategies. The behavior of UPQC has been analyzed with sudden switching of R-L loads, and R-C loads as well as occurrences of different shunt faults. The system has been modeled using MATLAB/SIMULINK 7.5. The control scheme has been devised using PI controller in UPQC for real and reactive power control, and operation in case of switching and faults in transmission systems.