Using IEC 61850 data transfer beyond the substation for enhanced protection for distribution networks

Protecting electricity distribution networks is becoming increasingly challenging and improved performance is continually being demanded. The growth in distributed generation, the opportunities offered by meshed networks and the service demands of consumers require smarter protection. Invariably, the solution will involve capitalizing on the developments in digital relaying and communications. This paper describes the findings of an investigation into extending the concepts of communications within the substation contained in IEC61850 beyond the substation in order to provide substation to substation communications. It introduces the basis for Fault Passage Relaying and current differential relaying for protecting distribution feeders and an associated internet communications scheme. This internet based communications scheme builds on the concepts behind IEC61850 and provides a substation to substation process bus.