The area angle is a scalar measure of power system area stress that responds
to line outages within the area and is a combination of synchrophasor
measurements of voltage angles around the border of the area. Both idealized
and practical examples are given to show that the variation of the area angle
for single line outages can be approximately related to changes in the overall
susceptance of the area and the line outage severity.Comment: adjusted version accepted at North American Power Symposium (NAPS),
Pullman WA USA, September 201
