Silicon Carbide Varistor Competitiveness in EHV Sfries Capacitor Reinsertion

Developments attained during the last decade in the field of non-linear resistor technolong Save introduced EHV series capacitor fast reinsertion as an attractive application area. The recently evolved Zinc Oxide (ZNO) scheme challenges, in a 500 KV expansion project in Argentina, the older Silicon Carbide (SIC) dual-gap arrangement applied to the current series compensation. A comparative parametric study drawing the relative merits of both concepts is presented for single- and three-phase fault criteria. The economic outlook, derived from the application of proposed reinsertion branch cost functions to the respective varistor energy absorptions, is complemented by the calculation of the associated rotor accelerating power as a measure of system stability. The conclusions drawn are broadened by including the consideration of a hypothetic (closer to the generation) alternative capacitor location.