Design of New Synchrophasor-Based Functions for Protection of Electric Power Systems

Settings of protection relays compromise between two contradictory aspects, dependability and security, to achieve a high reliability and minimize the occurrence of blackouts. New technologies like Wide Area Monitoring, Protection and Control (WAMPAC) can open new horizons to enhance the system performance.

This dissertation proposes two new protection functions as possible applications of WAMPAC. The first function proposes to base the setting of the relay on a probabilistic approach instead of the conventional deterministic approach. This way a new measure is included in the relay settings to indicate how sensitive to the measurement errors the tripping criterion is. Based on that, the protection reliability is highly enhanced. Other important advantages are illustrated throughout the thesis.

The second proposed function is of the preventive control type to control, using FACTS, highly loaded parallel transmission lines. Excess loading is cyclically shared between the lines such that the transmission corridor remains intact for as much time as possible to suppress cascade tripping.