Integration of a static VAr system into Fargo substation

The replacement of two synchronous condensers with a static VAr system (SVS) consisting of 64 MVAr thyristor controlled reactors (TCR), conventional breaker switched reactors (BSR) and breaker switches capacitors (BSC), at the existing Fargo substation located near Fargo, North Dakota (USA) was successfully implemented in March 1988. The SVS was integrated into the existing Fargo substation facilities in two stages: stage 1 involved removing two synchronous condensers and installation of a network of 13.2 kV BSRs and 115 kV BSCs; Stage 2 incorporated the installation of a 13.2 kV static VAR compensator (SVC) comprised of the TCR, harmonic filters and associated controls. The combined features of the stage work resulted in an SVS with a range of 135 MVAr inductive to 101 MVAr capacitive. The authors present the main features of the Fargo substation SVS including design criteria, control characteristics, operational benefits, circuit diagram, equipment ratings/layout, system implementation, commissioning, and operating experiences