CIGRE-Over Head Line Fault Locator

8/17/2019 CIGRE-Over Head Line Fault Locator

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Prashant Das Tauruspowertronics Pvt. Ltd

[email protected] www.tauruspowertronics.com

CIGREINDIA

mailto:[email protected]://www.tauruspowertronics.com/http://www.tauruspowertronics.com/mailto:[email protected]


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Transmission lines



• Transmission lines constitute more than 60%

transmission.

• They traverse an incredible range of kilomet

environments, climates and terrains.

• In India man

y of the Transmission lines curr

were built in the 1960s and 70s and are sub

problems including ageing.

• With growing demands, there is huge expec

transmission companies to keep the transmnear to 100%.

• Hence accurate fault location, health check

same is very much essential.



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Type of

commonfaults inoverheadTransmissionlines



All T

ypes of Open & Short Categ



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Overhead

Transmissionline faultlocator &

Analyzer



• Pre-Commissioning Check of EHV Li

Phase Sequence, line length verifica

• Ascert

aining line healthiness befor

• For Preventive & Predictive Mainte

existing EHV Lines.

• Restore the EHV lines ASAP to main



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FaultLocator andtypes offault locator



OVER HEADTRANSMISSIONLIN

LOCATOR (OHFL)

• Online

• Offline



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OHFLBasicPrincipals ofworking



• ONLINE-Systems works on the prin

system Parameters & Data is taken

breakdown condition and this dataaccuracy depending on the residua

the line.

• OFFLINE-Systems works on the prin

pulse Eco Co-relation technique &any input parameters for accurate fa



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Onlinemethodsome of it’s

limitations



• Each Line require one dedica

equipment.

• It is not helpful for spur lines

• Open Circuit faults can’t loc

online systems.

• Fault locating accuracy may v

percentage. (+/_ 10% or mor

• Pre-Commissioning tests are



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Offlinemethod



• Advanced high frequency multip

co-relation technique

• How it works:

- High frequency Coded pulse sethe powerline

- picks up different types of distu

and location

- Information Decoded

- Generates User Friendly Report

complete vision of the line end



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Offlinemethodsand it’sadvantages



• It’ is accurate up to +/- 100Mtr.

• One equipment is enough for whole

• It can be used for Spur line fault locat

• Pre –Commissioning tests are possible

• Offline system can identify the second

before re charging the line.

• It can find out Open Circuit faults.

• Does not require any complimentary

end of the sub station.

• It can Locate faults up to 2500KM.



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OfflineOHFLDiagnosticoutputs



•

Fault Locator(Breakdown): For findingaccurate distance.

• Line Signature Analysis: for understan

healthiness of the line.



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Overhead

transmissionline faultlocator

benefits



• Apart from finding dead faults , use

predictive and preventive mainteni) It can detect developing faults .

ii) It can detect nature of the fault(O

iii) It can indicate severity of the fault

Faults).

• Less time to find faults and its loca

• Healthiness check up for the entire



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CaseStudies



• Short circuit Fault

• De-capping• All jumpers not through in Quad

• Leaky Insulators

• Clearance related problems

•

High frequency effects on transm

CASE STUDIES SHORT CIRCUIT FAULT t 112 KM



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CASE STUDIES

Short circuit FaultDe-capping

All jumpers not through inQuad lineLeaky Insulators

Clearance related problemsHigh frequency effects ontransmission lines



SHORT CIRCUIT FAULT at 112 KM



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STUDIES

Short circuit FaultDe-capping All jumpers not through inQuad lineLeaky InsulatorsClearance relatedproblemsHigh frequency effects ontransmission linesPrashant Das Tauruspowertronics Pvt. Ltd


Decapping Fault at 69 Km in B

Decapping

Fault

STUDIES ALL JUMPERS NOT THROUGH AT



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STUDIES

Short circuit FaultDe-cappingAll jumpers not throughin Quad lineLeaky InsulatorsClearance relatedproblemsHigh frequency effects ontransmission linesPrashant Das Tauruspowertronics Pvt. Ltd


ALL JUMPERS NOT THROUGH AT

STUDIES Corona due to loose jumper



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STUDIES



Corona due to loose jumper

STUDIESSIGNATURE AFTER THROUGH JUMPER



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STUDIES



SIGNATURE AFTER THROUGH JUMPER

STUDIES Flashover insulator at 5 8 and 5 3 KM



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STUDIES



Flashover insulator at 5.8 and 5.3 KM

STUDIES



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STUDIES



STUDIES Trees very close to Transmission Line in



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STUDIES



Trees very close to Transmission Line in

STUDIES After Removal of trees



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STUDIES



After Removal of trees

STUDIES



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STUDIES



• Line Signature Analyser could identify the

caused by high frequency noise flowing o

insulators and flashover.

• Line Signature Analyser printout with an

reveal the presence of several kV’s of high

and really a cause for flash over of insulators

• The noise was later found due to paralle

thyristor switching action

STUDIESAnnexure

–A without filter



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STUDIES

Short circuit FaultDe-capping All jumpers not through in

Quad lineLeaky InsulatorsClearance relatedproblemsHigh frequency effects ontransmission linesPrashant Das Tauruspowertronics Pvt. Ltd


Padghe – BBLR – gain 1 without filter-Lots of n

STUDIESAnnexure

–B with HVDC filter



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STUDIES

Short circuit FaultDe-capping All jumpers not through in

Quad lineLeaky InsulatorsClearance relatedproblemsHigh frequency effects ontransmission linesPrashant Das Tauruspowertronics Pvt. Ltd


Padghe – BBLR – Gain1 No noise observed

CASE

Case Studies of 25 lines taken in a Transmission ZONE during 2011-2012 . Statistics arrecord maintained for 365 days



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CASESTUDIES

OFFLINEOVERHEADLINE FAULTLOCATOR



record maintained for 365 days

Line

Lengths in

KMs

Without

OHFL time

taken to

rectify the

fault in a

line (Hrs)

With

OHFL

time

taken to

rectify

fault in a

line

(Hrs)

No. Of

Lines in

the Zone

(Total

Sample 25

lines)

Average

No. of

Tripping

in a

Year/Line

Total

Trippi

ngs in

a Year

Ideally

with

OHFL

time

would

have

taken

OHFL

used

at

Time

taken to

find

fault

with

OHFL in

( Hrs)

O

u

0 to 150

KMs15 3 19 3 57

171

hrs

30

places

90

hrs p

150 to

250 Kms19 4 4 2 8

32

hrs

5

Places

20

hrs P

250 to

350 Kms23 4 2 2 4

16

hrs

1

places

4

hrs p

Case

C St di f 73 li i Utilit T i i



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CaseStudies

OFFLINE OHFL

Line

Signature



Case Studies of 73 new lines in a Utility Transmission

KV of the line No.of Lines

No of Tripping

Without Line

Signature test

No.of Lines signatu

test was done

132KV 5 3 3

220KV 20 11 9

400KV 40 16 14

765KV 8 3 3



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Importantparameters-

whilechoosing anoverheadtransmis

sion line faultlocator



• Equipment should be Portable & Ba

•Induction Voltage Suppression capa

• Auto Impedance matching facility f

used in any EHV Lines.

• Instrument should be EMI/EMC Co

PAPER



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PAPER

Presented by

POWERGRID IN CBIP– INTERNATIONALCONFERENCE

Using Offline FaultLocator

TO DIAGNOSE THETRANSMISSION LINE





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Thank

you foryour

attendan

ce



For more information Write to :

PRASHANT DAS

prashant.das@tauruspowertronic

+91 9766355355
mailto:[email protected]://www.tauruspowertronics.com/mailto:[email protected]:[email protected]://www.tauruspowertronics.com/mailto:[email protected]

Documents

CIGRE-Over Head Line Fault Locator