A study of correlation between protection trips and geomagnetically induced currents in a power transmission line in Brazil

This paper presents analyses of data in view of obtaining a possible correlation between geomagnetic activity and protection trips in a 138 kV-197.12 km power transmission line in southern Brazil. Most of these outages are caused by faults randomly located along the line. In consequence, many studies have been done to identify the main reason for these events, now including the investigation of the phenomenon of Geomagnetically Induced Currents (GIC) as being the cause of the problems that affect the reliability of the protection system of that and other power transmission lines. Preliminary results shown in this work allow identifying the degree of dependence between geomagnetic activity and occurrence of protection trips for the studied line.