Distributed protection, control and recording in IEC 61850 based substation automation systems

This paper describes GOOSE and GSSE messages as defined in IEC 61850 and how they can be used for different distributed applications. Merging units based on IEC 61850 9-2 send sampled values that can be used by communications based intelligent electronic devices (IED) to further reduce the hard wiring in a substation. Distributed protection applications example includes directional comparison bus protection. Distributed waveform recording of short circuit faults or other abnormal system conditions based on different types of IEDs is also discussed in the paper. Distributed fault and event recording based on the reporting features of IEC 61850 is presented as well. The primary and backup protection, control, monitoring and recording functions are distributed between different multifunctional IEDs and the substation client. The described distributed applications result in an integrated substation automation system that meets all functional requirements, while at the same time the overall cost is reduced due to the reduced wiring between the substation primary equipment and the IEDs.