T-30 2008 TAMU, GaTech and WSU. 1

Transient Testing of Protective Relays: Study of Benefits and Methodology

(T-30)Mladen Kezunovic, Texas A&M University

Sakis Meliopoulos, Georgia Institute of TechnologyWard Jewell, Wichita State University

PSerc IAB Meeting Ames, IA - May 14-16, 2008

T-30 2008 TAMU, GaTech and WSU. 2

Industry Advisors

z Bajarang Agrawal (APS)z Ali A. Chowdhury (Mid American) z John Horwath (Exelon) z Joseph Hughes (EPRI)z Richard Hunt (NxtPhase)z Bill Middaugh (Tri-State) z Don Sevcik (CenterPoint Energy)

T-30 2008 TAMU, GaTech and WSU. 3

Overview

Part I: Distance Relay TestPart II: Generator Relay TestPart III: Load Shedding Relay TestConclusion

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Part I: Distance Relay Test

Test MethodologyTest ScenariosLaboratory SetupSummary

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Test Methodology

Power System Modeling: Select standard power system models suitable for creating various disturbance scenarios.

Test Scenarios: Generate a set of test scenarios through simulation, and/or collect records from disturbances of interest

Test Implementation: Automate the simulation to minimize the test time; Implement comparative tests for a set of different relays with similar functions.

Analysis and Report: Collect relay responses, analyze the results and summarize them in a test report with comparative results analysis

Library of Test Cases: Form a library of test cases for easy reuse and utilization as a future reference.

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Test Classification

Conformance Test: To test the basic functionality of the relays,verify the operating characteristics, calibrate relay settings andimplement periodic maintenance test.

Compliance Test: To verify whether a relay can operate correctly under peculiar circumstances in power systemparticularly during abnormal operating conditions.

9 Transient signals9 Statistical performance9 The trip/no trip response 9 Tripping/operating time 9 Faults and non-faults scenarios

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Test System Model

IEEE PSRC system for the Conformance Test

nZL2 (1-n)ZL2

FaultLocation

mZL1 (1-m)ZL1ZM

ZL4

TR2

S2S1

RELAY

Alternate PotentialLocation

RELAY

Alternate PotentialLocation

BUS 1 BUS 2 BUS 4

BUS 3

RELAY

Alternate PotentialLocation

SW

ZL3S3

PTCT

L5

G

G

G

G

G

1

6

7

11 10 9

8

5 4

32

13

12

14

IEEE 14-bus system forthe Compliance Test

Two power system models are used to simulate disturbance for the conformance test and compliance test

Both automatic and manual simulation were implemented in ATP

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Test Scenarios

Conformance Test Fault Scenarios (Dependability) Internal Fault External Fault Switch onto Fault Fault during Power Swing One-End-Open Internal Fault Internal Fault during Frequency Fluctuation Non-fault Scenarios (Security) Line Closing Loss of Potential Loss of Load Power Swing Restoring the Potential Load Encroachment

Compliance Test Vulnerable Lines (Overload) Dynamic Conditions (Impedance Trajectory)

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Test Scenarios

Automate simulation with various disturbances with different fault types, locations, inception angles and resistances

Batch simulation program block diagram

Output COMTRADE file for waveform playback and post-event analysis

ATPdraw model for manual simulation

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Laboratory Setup

9 PC based platform9 Digital simulator9 Relay Assistant Laboratory setup for protective relay test

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Summary

Test Methodology Test Classification Power System Modeling Test Procedure

Test Scenarios Transient-based Steady State Dynamic State

Test Laboratory Setup Test on three distance relays

SEL-321 SEL-421 GE D60

The library of test cases

Test results in the Final Report

Transient Testing of Protective Relays: Study of Benefits and Methodology(T-30)Industry AdvisorsOverviewPart I: Distance Relay TestTest MethodologyTest ClassificationTest System ModelTest ScenariosTest ScenariosLaboratory SetupSummary