Consideration of the IEC 61850 protocol and implications for substation engineering.

Master of Science in Electrical Engineering. University of KwaZulu-Natal, Durban, 2018.This dissertation presented a study on the future-proof IEC 61850 communication protocol and its implications for substation engineering. The advent of contemporary technologies has resulted in the decentralization of substation architecture. Over the last 15 years the IEC 61850 protocol has been contributing to the refurbishment and upgrade of conventional substations. As the aging infrastructure of these centres has been slowly replaced, the hybrid substation has begun to emerge. These substations have been known to contain tedious combinations of different proprietary protocols all attempting to operate within the same substation network. Therefore, the introduction of IEC 61850 to old substations can have an effect on automation, protection and communication within the substations local environment. In this dissertation a multi-protocol substation communication network and SCADA was established using DNP3, Modbus RTU and IEC 61850. A communication network was developed between a physical nexus of connected IEDs and end equipment. It was from this model that the operation of a typical substation automation system was analysed. This critical assessment focussed on the workings of the remotecontrol points as well as the response of end equipment under fault conditions such as breaker fail, overcurrent and earth fault. In addition to the operation of the multi-protocol model, individual inferences could be drawn from the implementation of the aforementioned protocols themselves. These deductions related to the significance of time stamped data, the reduction of cross-wired copper cables within substations, the obvious limitations of serial RS 485 Modbus RTU and the convenient benefits of ‘virtual’ networks. It was during the main research phase of this study that the principal benefits of the IEC 61850 standard were readily enforced and interpreted. Furthermore, special consideration was given to the implications of the GOOSE message class on substation protection. It was here that GOOSEbased breaker fail protection, arc-flash protection and blocking response were investigated. As a result of the implementation of these protection schemes it was determined that GOOSE messaging and by extension the IEC 61850 standard provides optimisation, economic benefits as well as revolutionary advancements in protection and automation to substations. The IEC 61850 substation standard is current, universal, promotes the interoperability between devices and is a leading contributor in the development of smart grids. Therefore, IEC 61850 is a standard of the present and of the future