ASSESSMENT OF TRANSMISSION RISKS AND RESILIENCE OF THE NORTH AMERICAN BULK POWER SYSTEM

摘要

The North American Electric Reliability Corporation (NERC) uses transmission equipment inventory and outage data collected in its Transmission Availability Data System (TADS) to identify significant reliability risks to the bulk power system (BPS). The paper presents results of the analysis that quantifies and ranks impact of different causes initiating transmission outage events in North America. The impact is measured by transmission outage severity of an event determined by the number of affected ac circuits and transformers as well as their voltages. An important measure of the transmission system resilience, the event duration (a recovery time), is also analyzed and taken into account in the evaluation of transmission risks to the BPS. For example, Weather, excluding lightning and Failed AC Circuit equipment are two most frequent causes of sustained automatic outage events but impact of an individual event they initiate is relatively small. In contrast, Power system condition, Fire, Misoperations, Failed ac substation equipment cause fewer transmission events; however, these events have significant impact to the BPS since they tend to involve more circuits and transformers. Additionally, Failed ac substation equipment initiates, on average, longest events than other causes. The study is based on the 2015-2018 TADS data.