Harmonic Distortion Influence on Grounded Wye Shunt Capacitor Banks Protection: Experimental Results

The increase of harmonic current circulation in electric system affects the shunt capacitor banks protection arrangement, causing false alarms and trips and leading to a reduction of the relay sensitivity. This paper analyzes the behavior of the protection system on a reduced-scale model, which reproduces the main features of grounded wye shunt capacitor banks. In such experiments, high levels of current harmonic distortion, voltage unbalance, and bank inherent unbalance were considered. This paper brings experimental analyses for protection arrangements considering robustness and sensitivity.