Trees, Power Lines and NERC An Interview With NERC CEO Gerry Cauley

摘要

Cauley: Poor vegetation management was a key contributor in the August 2003 blackout in the Northeast. Three high-voltage lines in Ohio relayed out in the span of approximately an hour, acting as the trigger for a wide-area cascade of the system and the largest blackout in North American history. Improperly maintained right-of-way clearances create a situation where power system failures are not random, but systemic, such as we saw in Ohio in August 2003. It is essential that transmission line owners maintain safe clearances on their energized equipment. Not only do we have the issue of lines relaying out in a nonrandom fashion, we also assume that line ratings are valid based on the amount of sag caused by line heating. If the clearances are not sufficient, then the line ratings can become compromised and the reliability analysis we use to ensure the power system is in a safe state can become invalid.