Screening digital relay data to detect power network fault response anomalies

An important part of power line protection system maintenance is the retrospective analysis of fault data to verify that all elements of the protection system were set properly and operated as they should have. In this paper, we describe an automated approach to detecting anomalies using data from microprocessor-based digital protective relays. At present, the systems are specific to the ABB Relay Division MDAR relay family. However, the techniques used are generalizable to other types and brands of digital relay.