Vtb2005 Shin

Application of VTB for Localization of Capacitor Switching Events in Power Distribution Yong-June Shin, Assistant Professor Department of Electrical Engineering, The University of South Carolina 2005 VTB Users and Developers Meeting September 20-21, 2005

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Acknowledgement • ESRDC, University of Texas at Austin – Dr. E. J. Powers, Dr. W. Mack Grady – Mr. T. H. Kim

• ESRDC, University of South Carolina – Dr. Eugene Solodovnik, Dr. A. Monti – Mr. Philip Crapse

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Contents • • • • •

Introduction to Fault Localization Cross Time-Frequency Analysis MATLAB based Fault Localization Tool VTB Simulation Environment Conclusion and Future Work

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Transient Fault Localization • Purpose of localization  Identify the flow and location of transient disturbance  Management of power distribution system (e.g., capacitor bank switching)

• State-of-the-Art

• An example of power system

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Empirical approach Signature analysis Time domain analysis Frequency domain analysis

network with capacitor banks

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Directions of P and Q Under steady state, • If P>0, circuit absorbs real power • If P<0, circuit supplies real power • If Q>0, circuit absorbs reactive power (I lags V) • If Q<0, circuit supplies reactive power (I leads V) 5

Challenges for Transient • Time Localization • Frequency Localization • Phase Difference Estimation – Cross Time-Frequency Analysis! Observation point 1

Upstream capacitor A

Observation point 2

Middle capacitor B

Downstream capacitor C

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Time-Frequency Based Transient Fault Localization Algorithm • Transient fault localization is achieved by Step 1: Voltage and current measurement (V1 & I1, V2 & I2) Step 2: Cross time-frequency distribution Step 3: Time and frequency of interest selection Step 4: Localized phase difference evaluation Step 5: Disturbance energy flow direction decision (upstream, middle, downstream)

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VTB Simulation Environment Transient Power Quality Analysis Information of Simulation System

VTB Schematic Simulated System Information

Post Signal Processing

VTB Visualization Engine Real time update of data and visualization

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Conclusion and Future Work • VTB Simulation Environment • Post-Processing of Simulation • Cross Time-Frequency Analysis • Fault Localization and Monitoring – Electric Ship Integrated Power Systems – High Power Transmission Line Systems – Power Distribution Systems Management

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