ABSTRACT
Modern electric power systems have been dubbed “the largest machine made by mankind” because they are both physically large-literally thousands of miles in dimension-and operate in precise synchronism. In North America, for example, the entire West Coast, everything east of the Rocky Mountains, and the state of Texas operate as three autonomous interconnected “machines.” e task of keeping such a large machine functioning without breaking itself apart is not trivial. e fact that power systems work as reliably as they do is a tribute to the level of sophistication that is built into them. Substation communication plays a vital role in power system operation. is chapter provides a brief historical overview of substation communication, followed by sections that
• Review functional and communication requirements • Examine the components of both traditional and emerging supervisory control and data acquisi-
tion (SCADA) systems • Review the characteristics of past, present, and future substation communication protocols • Review the role of standards for substation communication • Discuss the electromagnetic environment which substation communication devices must
withstand • Discuss security aspects of substation communications • Discuss communication media options for substation communications
Electric power systems as we know them began developing in the early twentieth century. Initially, generating plants were associated only with local loads that typically consisted of lighting and electric transportation. If anything in the system failed-generating plant, power lines, or connections-the lights would quite literally be “out.” Customers had not yet learned to depend on electricity being nearly 100% reliable, so outages, whether routine or emergency, were taken as a matter of course.
