Criteria and methodologies established in the ambit of GTAD/SCEL/GCOI Voltage Collapse Task Force for studies on voltage stability in the Brazilian North/Northeast, South/Southeast and North/South interconnected systems

The Voltage Collapse Task Force was created at a plenary meeting of GTAD (working group on performance analysis)/SCEL (electrical studies committee)/GCOI (coordination group on interconnected operation) in March of 1998, with the aim of establishing methodologies and defining criteria for studies on voltage stability as well as reevaluating both manual and automatic load shedding schemes by undervoltage in the Brazilian South/Southeast and North/Northeast Interconnected Systems. Several areas of the South/Southeast, North/Northeast and North/South Interconnected Systems have been studied in order to define their peculiarities. The first outlines of methodologies for studies on voltage stability started to be designed and afterwards were improved step by step. The following stage contemplated the definition of criteria for studies on voltage stability