Automated Post-Event Analysis of the Protection System in Distribution Substations

It is important that electrical networks have high levels of reliability in order to maintain the ideal agility and maintenance for better functioning. This fact combined with the increasing amount of information available in modern digital relays advances the idea of implementing systems that assist achieve fast and correct decisions on the protection system functioning. The purpose of this project was to implement a system that responds in an automated manner to protection-related events in distribution substations, providing a quick and complete diagnosis. The work has two foci. The first is the communication system based on an IEC61850/OPC server and the process automation through a client program. The second is an expert system that analyzes protection-related events based on data collected from the relays. An important result was the possibility of generating a correct diagnosis based on different data sets. This is extremely important, since one cannot expect exactly the same set of information for analysis, which should not prevent the delivery of a diagnosis. This system was installed in a substation of Companhia Paulista de Força e Luz, a Brazilian power distribution utility.