Application of Equal Area Criterion Conditions in the Time Domain for Out-of-Step Protection

• Published in: IEEE transactions on power delivery Vol. 25; no. 2; pp. 600 - 609
• Main Authors: Paudyal, S., Ramakrishna, G., Sachdev, M.S.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2010; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acceleration; Algorithms; Applied sciences; Buses (vehicles); Computer simulation; Connection and protection apparatus; Digital; Digital relays; Disturbances. Regulation. Protection; Electrical engineering. Electrical power engineering; Electrical power engineering; Equal area criterion; Exact sciences and technology; Hardware; out-of-step; Power networks and lines; power swings; Power system relaying; Protection; Real time; Relay; relays; Software algorithms; Software prototyping; Software systems; Software testing; System testing; Time domain; Performance evaluation; out-of-step; Closed loop; Relay; Prototype; Power oscillation; Power system stability; relays; Infinite system; Algorithm; Implementation; Bus system; Computer hardware; Time domain method; Classification; Time curve; System simulation; Software; Simulator; Single machine; Equal area criterion; power swings
• ISSN: 0885-8977; 1937-4208
• DOI: 10.1109/TPWRD.2009.2032326

A new procedure for out-of-step protection by mapping the equal area criterion conditions to the time domain is proposed in this paper. The classification between stable and out-of-step swings is done using the accelerating and decelerating energies, which represents the area under the power-time curve. The proposed methodology is simple and overcomes some of the difficulties associated with the previous techniques. The proposed approach is based only on the local electrical quantities available at the relay location, and does not depend on the network configuration and parameters. The proposed algorithm has been tested on a single-machine infinite bus and a three-machine infinite bus system using software simulations. A digital prototype of the relay has also been implemented on the hardware and its performance has been assessed in a closed-loop mode using a real-time digital simulator. The simulation results and the hardware testing results confirm the validity of the approach presented.