Fast bus protection using IEC 61850

International Electrotechnical Commission (IEC) 61850 is the latest technology that allows electric power utilities to build low cost digital substations. Because limited objective information is available, electric power utilities desire independent evaluations of IEC 61850 from end users. The objective of this study is to compare the IEC 61850 method to the hardwired method using actual hardware to find an optimal solution for the fast bus protection scheme. System disturbance clearing time, maintenance and construction costs, and interoperability between multivendor microprocessor-based relays were used as the criteria for this evaluation. This research measured the protection speed of the hardwired method and the IEC 61850 method for the fast bus protection scheme, utilizing relays from the same and mixed manufacturers. The results of the study show that IEC 61850 method is simple, cost efficient, and offers speed of operation comparable to the hardwired method.