The use of real time digital simulation for performance analysis of distance protection and differential protection in short transmission lines

The purpose of this article is to present a performance analysis of distance protection and differential protection applied on 4 (four) short transmission lines of ISA CTEEP (Companhia de Transmisão de Energia Elétrica Paulista), a Brazilian power transmission utility. The performance analysis was based on the digital simulations results of distance and differential numeric protective relays on power transmission lines, realized between March and April of 2006 at SIEMENS AG's facilities (Erlangen - Germany), using Real Time Digital Simulator (RTDS™), Several types of faults simulations were accomplished, in several conditions of the electrical power transmission systems where the protective relays would be installed. The results are presented not only with the times of faults elimination, but also with all functionality and advantages that these modern devices make possible to the electrical power transmission systems.