Enhanced Protection Security Using the System Integrity Protection Scheme (SIPS)

Events, such as faults, loss of load, or generation may cause unwanted relay operations which initiate cascade tripping leading to system collapse. Security of power system protection is a major concern for utilities. A system integrated protection scheme-based approach is proposed for improving the security of protection operations. Identification of vulnerable points, which may maloperate during a stressed condition and initiation of preventive strategy, is proposed in this paper. Synchronized measurements obtained from strategic locations in the system are used for this purpose. It includes two algorithms; the first of which changes the operating characteristic of relays in accordance with system condition. The second one identifies nodes in the system where load reduction can reduce the risk of maloperation. The proposed method is tested for the New England 39-bus system and is found to be accurate.