Operation of the Large Interconnected Power System by Decision and Control

A comprehensive approach to the control of the large interconnected power system in conditions ranging from normal to disintegrated is outlined. The basic decision is between normal and abnormal conditions or, more precisely, on the degree of abnormality with normality rating as zero degree abnormality. The applicable control algorithms would then be aimed at maintaining normalcy when it is present or leading the system back to normalcy with the least disruption when the condition is abnormal. In a sense one could say that in Decision and Control operation a system is always in a restoratory state seeking the best way back to normalcy-when it finds nothing to restore the system is in a normal condition. To lead the system back to normalcy five Regimes of Control are defined and the measures and means used in each are defined and developed. New ancillary algorithms to use as tools in these operations have been developed. An illustration of a sequence of emergency events under Decision and . Control Operation is also included. A measure of the effectiveness of the new techniques is a consistent tenfold increase of critical clearing times. This indicates a large potential saving in new transmission equipment.