Communications Project

Document Type:Master's Thesis
Name:Richard K. Hunt
Title:Hidden Failure in Protective Relays: Supervision and Control
Degree:Master of Science
Department:Electrical & Computer Engineering
Committee Chair: Dr. Arun G. Phadke
Committee Members:Dr. Robert P. Broadwater
Dr. Yili Liu
Keywords:Relay, Protection, Power Systems, Computer
Date of defense:February 26, 1998
Availability:Release the entire work immediately worldwide.


This thesis performs a simulation of a relay supervisory system (RSS) that works passively in conjunction with the existing protective relaying system at a substation. During normal system operating conditions, the RSS supervises the relay system to prevent trips due to hidden failures. During wide area network disturbances, it adapts the relay system to increase security of the power system. The RSS works passively in the sense that it waits for events to occur in the existing relay system before taking any action.

The simulation performed includes a model of the RSS, along with simplified models of existing relays, performed in Matlab. A power system model in EMTP provides inputs to the RSS model. Multiple faults are applied to the EMTP model, and the RSS is tested under each fault condition, and with a variety of relay hidden failures. For all tests performed, the simulation of the RSS successfully prevents relay hidden failures from removing circuit elements inadvertently, while allowing correct relay operations to remove circuit elements.

List of Attached Files

AppendixI.pdf AppendixII.pdf AppendixIII.pdf
AppendixIV.pdf AppendixV.pdf AppendixVI.pdf
AppendixVII.pdf Chapter1.pdf Chapter2.pdf
Chapter3.pdf Chapter4.pdf Chapter5A.pdf
Chapter5B.pdf Chapter6A.pdf Chapter6B.pdf
Chapter7.pdf Chapter8.pdf HUNTABSTRACT.PDF References.pdf
System.dat Title.PDF
toc.pdf vita.pdf

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