Transmission system parameters optimization-sensitivity analysis of secondary arc current and recovery voltage

This paper shows the importance of optimizing the transmission system parameters from its conception, considering the relevant options and possibilities, in order to have a better cost-performance result. The presented results were obtained in the study of a real transmission system expansion, based on a 865-km long line. The single-phase auto-reclosing (SPAR) procedure was one of the aspects carefully studied, in order to assure adequate transmission reliability. The secondary arc current was mitigated through the traditional solution of using the neutral reactor on the existing shunt reactor banks, which permitted the reduction of the secondary arc current to acceptable values, assuring natural arc extinction and successful SPAR. The method of obtaining the optimized value for the neutral reactor and its implications on the system performance are important aspects, and are discussed in this paper.