Reliability improvement of the 500 kV and 230 kV substations on the North/Northeast Brazilian transmission system using PLC network and substation main bus sectionalizing

The main purpose of this article is to inform about the studies being performed covering the 500 kV and 230 kV major substations of the North/Northeast (N/NE) Brazilian transmission system with respect to its intrinsic security, which includes the aspects of physical configuration of the buses, as well as the main and backup protection system philosophy used. Also, included as part of this article, are the solutions that are being proposed to improve the system general reliability, as well as the sectionalization of the main bus on substations with only one operating bus. The use of a PLC network to provide reconfiguration actions based on a multiple contingency criteria for situations, which may lead to system instability, or important loss of load is mentioned briefly. Finally, a few recommendations are presented for new substations, in order to improve their performance.