Millisecond, microsecond, nanosecond: What can we do with more precise time?

Our industry moves energy at the speed of light, at the flick of a switch. A transmission line transporting 1500 megawatts delivers the equivalent of 250 pounds of coal per second, already converted into a convenient form of energy. For decades, we considered time in seconds or cycles: such as fuse curves and breaker clearing times. About three decades ago, our thinking moved into milliseconds because we needed to get better at quickly understanding wide-area events, protection was getting faster allowing for more power transfer, and the technology made it possible. Over the past decade, we have come to appreciate how synchrophasors can help us understand, control, and protect our power systems. One electrical degree at 60 hertz is about 46 microseconds, so measurements accurate to ten microseconds give us accurate synchrophasors. Traveling-wave technologies can put nanosecond resolution to good use. Achieving nanosecond absolute time is practical, affordable, and useful. In this paper, we explore how more-accurate time can improve the performance of electric power systems.