Numerical distance protection performance analysis in short and long transmission lines using real time digital simulation

The main purpose of this work is to present a performance analysis of numerical distance protection applied in high voltage transmission lines, more specifically in the 500 kV transmission lines of CEMIG (Energy Company of Minas Gerais - Brazilian Energy Utility) between the Vespasiano 2 - Neves 1 (short line - 23.9 km) and Vespasiano 2 - Mesquita (long line - 148.6 km) substation. The need for energy reliability and quality in power transmission resulted in the choice for multifunction numeric protective relays in transmission lines that could assure the equipments and transmission lines security with the continuity and stability warranty for CEMIGpsilas transmission system. Simulations and test were requested to analyze the numeric distance relays behavior that would be installed in the Vespasiano 2, Neves 1 and Mesuita 500 kV Substations. The paper will realize the performance analysis and evaluation of the same numerical distance protection applied in both transmission lines using real time digital simulation.