Accurate Fault Location Using Detailed Transmission Line Models

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Accurate Fault Location Using Detailed
Transmission Line Models

• NSF/EPRI Workshop
• M. Kezunovic
• Texas AM University
• March 29, 2002

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ACCURATE FAULT LOCATION

• ACCURACY OF 1
• NOT AFFECTED BY Rf
• NO IMPACT OF MUTUAL COUPLING
• WORKS WITH HIGH SPEED AUTOREC.
• TRANSPARENT TO FAULT TYPE
• WORKS FOR TRANSP. AND UNTRANSP. TRANSMISSION
  LINES
• BASED ON ACCURATE EMTP MODEL

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NEW FAULT ANALYSYS CONCEPT
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ACCURATE FAULT LOCATION
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THE BASIC PRINCIPLE
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S AND R EQUATIONS
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EQUATION FOR PHASE a
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FAULT LOCATION EQUATION
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WAPA TEST SYSTEM
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WAPA TEST SYSTEM

• FAULT LOCATIONS
• FAULT TYPES
• FAULT INCIDENCE ANGLE
• FAULT IMPEDANCE
• SERIES CAPACITORS
• INSTRUMENT TRANSFORMERS

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TEST RESULTS
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TEST RESULTS
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FACTORS AFFECTING ACCURACY

• SAMPLING FREQUENCY
• EMTP MODEL ACCURACY
• USE OF SHORT ANDLONG TRANSMISSION LINE MODELS
• TRANSPOSITION POINTS
• COUPLING WITH THE LINES THAT END AT OTHER BUSES
• SAMPLING SYNCHRONIZATION

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CONCLUSIONS

• USING MODEL-BASED TECHNIQUES
• ACCURATE FAULT LOCATION USING SYNCHRONIZED DATA
• THE NEED FOR ON-LINE PARAMETER ESTIMATION AND
  MODEL IDENTIFICATION
• AN ULTIMATE RELAYING SCHEME, BUT SLIGHTLY DELAYED
  ACTION DUE TO EXTENSIVE COMMUNICATION NEEDS