Better, faster, and more economical integrated protective relaying and control using digital bits and logic

Improvements in protection and control via communications methods used to exchange digital bits among devices are common in progressive utilities in high-voltage substations. These improvements are now being incorporated into the process-sensitive electric power distribution systems of large industrial plants. Until now, new equipment purchases for new projects in industrial facilities using microprocessor (muP) multifunction protective relaying technology were typically done as a direct replacement of older technologies or as an updated equivalent. This paper describes a recently commissioned electrical substation design philosophy, including implementation, construction, maintenance, and performance with muP-based protective relaying, metering, and control schemes. These schemes extensively utilize the interdevice digital bits exchange and programmable logic capabilities of time-synchronized muP technology.