Critical Outage Determination via a Sensitivity Study of the Portuguese Electric Transmission Network

Abstract
Since the entry into service of the so-called Primary Network in 1951 until the 1960s, when the first electrical power interconnection between Portugal and Spain was created, that the Portuguese National Transmission Network could be considered a closed system, however, since the year 1961, that was no longer true. Taking these facts into account, the need to think and draw up new standards and regulations, with the widest possible coverage, has arisen in order to oblige European operators to maintain a level of control, security and knowledge of their transmission networks, which ensure that these do not influence each other negatively and that there is a coordinated response to incidents that may occur.