Modelling and Application of Secondary Circuit Signals for Power Grid Intelligent Alarm

Power grid intelligent alarm and fault diagnosis program mainly use breaker and relay action alarms. However, there may be misoperations existed in relays, which could leads to incorrect diagnosis results. With the development of digital substation and application of IEC61850, the secondary circuit signals are available from integrated automation system in substation. These signals may imply control or interlock relationship between relay alarms, which can be used to get rid of misoperation alarms in intelligent alarm functions. This paper mainly concerns about how to integrate these signals into power grid diagnosis procedure. Firstly, we survey the available secondary circuit signals for diagnosis purpose. Secondly, a model of secondary circuit signals is proposed which is an extension of IEC61850. Then, the diagnosis methods considering secondary circuit signals are presented. Lastly, an example is presented to illustrate the proposed methods practical.