Design and Fabrication of a Unified Power Quality Conditioner (UPQC)

The two major power quality problems in the distribution system are sagging and swelling of line voltage and harmonic currents. The communication, microcontroller and microprocessor based industry is much more affected by power quality (PQ) problems as their requirement for working and stability is compromised without high quality of power. By mitigation of current and voltage at point of common coupling such power quality problems can be decreased. The Unified Power Quality Conditioner (UPQC) is the most versatile and complex power electronic equipment that has ever emerged for the control and optimization of power quality in electrical power distribution system. This research presents improvement of power quality through a UPQC placed at load side. The proposed UPQC is integration of series and shunt converters. The series converter can compensate voltage fluctuation in the ac source due fault. Also, it can be used to regulate voltage sag and the under voltage situations. On the other hand, the shunt converter can compensate the current harmonic and improve the power factor. UPQC was simulated and demonstrated at 220V distribution level.