Two novel schemes suitable for static switching of three-phase delta-connected capacitor banks with minimum surge current

Delta-connected capacitor banks are used for power factor improvement of balanced three-phase loads (e.g., three-phase induction motors, etc.) and are normally switched in and out using antiparallel thyristors. This paper describes two new schemes for switching delta-connected capacitor banks. While the first scheme can be readily used for existing delta-connected capacitor banks, the second scheme can switch delta-connected capacitor banks in and out very quickly and, hence, is suitable for static VAr compensator (SVC) applications.