Application and Operation of a Static Var System on a Power System-American Electric Power Experience Part I: System Studies

American Electric Power´s (AEP) Static Var System (SVS) was placed in service at the Beaver Creek Station in eastern Kentucky in November 1980 and has since maintained an excellent record of operation. The purpose of this SVS installation was to provide both steady-state and dynamic voltage control on the 138 kV transmission system. This paper describes the application and operating experience of this unique installation, which is comprised of two thyristor controlled reactors (TCR) and two thyristor switched capacitors (TSC) with an overall dynamic range of ±125 MVAR. These components are connected to the 138 kV transmission system via a 125 MVA, 138/ 8.3 kV transformer. The +125 MVAR upper limit has been extended to +325 MVAR by installing four 50 MVAR, 138 kV capacitor banks which, in effect, function as a steady-state voltage control to optimize the SVS dynamic range.