POWER QUALITY IMPROVEMENT USING UPQC

Abstract

Shunt Active Power Filters Technology has developed hugely in the last 25 years. Now these are used for harmonic current compensation, supply reactive power to the AC distribution side and it is also required for Neutral Current Compensation. So many varied configurations, control strategies have come to the fore. It has also been aided by the development in the high power switches. They have been satisfactorily used for Terminal Voltage regulation and repression of voltage flicker for three phase systems. Depending on the requirements appropriate configuration and control strategy needs to be used. Since the incoming of the electronics age and use of solid state electronics devices power quality issues have come up as most of these electronics devices have diode bridge rectifier and other electronics configuration which contributes significantly to the power quality problems. Large number of researchers have worked on this power quality measurement, analysis and have given ingenious ways to tackle it. It is the consensus of the wider research community and the people in the industry that Shunt active power filter is the best device for tackling power quality problems. In this report at first an overview has been given for shunt active power filters first. Then idea has been given regarding the reference current generation technique used. Then it has been described in detail how to implement this current control technique in DSP. All the problems and various aspects have been highlighted which arise while implementing in DSPs. Then the Current control techniques which has been used has been discussed and then a comparative analysis has been done. The superiority of Space Phasor Based Hysteresis Current Control has been proved over normal hysteresis current control. Then the hardware results have been highlighted and properly shown