Performance of e Line Surge Arresters of e 110 kV Overhead...

Performance of the Line Surge Arresters

of the 110 kV Overhead Lines on the

Island Brač

Prof. Ivo Uglesic

Bozidar Filipovic-Grcic, PhD

Faculty of Electrical Engineering and Computing

University of Zagreb, Croatia

9th Annual Grounding & Lightning Conference, October 3 - 4, 2017 • San Antonio,Texas 1

2

Presentation outline

Lightning Locating System (LLS) & Lightning Data

LLS in Power System Control

Outages of Overhead Lines (OHL) due to the Lightning

Time and Spatial Correlation between LLS data and relay

protection system data

110 kV transmission network of the island Brač

LSAs installation

Conclusion

9th Annual Grounding & Lightning Conference, October 3 - 4, 2017 • San Antonio,Texas

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Lightning location system LINET – sensor positions


Lightning detection


VLF/LF frequency range for

detection of lightning strokes

TOA (Time-Of-Arrival) method

for locating lightning

Lightning sensor measures magnetic

flux in time in frequency range

(1 kHz – 200 kHz)

LINET 3D algorithm for

determination of lightning altitude

Lightning stroke(offshore Dubrovnik)

Data flow:

Sensors -> LINET center -> Users

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Isokeraunic map of Croatia

BOSNIA AND HERZEGOVINA

HUNGARYITALY

Isokeraunic map

annual thunder days expected

with 50 % probability


Thunderstorm movement monitoring

12.9.2017.00h – 24h

* 1h frames

347 533lightning strokesdetected

LLS measured lightning data


9 years of lightning data On-line sensor sensitivity and network quality monitoring

6.532.464 6.254.829

4.758.966 4.680.014

5.791.438

8.964.239

5.625.625

13.976.505

4.796.048 4.682.585

3.822.951 3.656.5554.430.847

7.400.058

4.655.689

10.722.880

1.736.416 1.572.244936.015 1.023.459

1.360.591 1.564.181969.936

3.253.625

0

2.000.000

4.000.000

6.000.000

8.000.000

10.000.000

12.000.000

14.000.000

16.000.000

2009 2010 2011 2012 2013 2014 2015 2016

Year

No. of Lightning Strokes by Year

Ukupno Oblak-Zemlja Oblak-oblakTotal CG IC

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LLS measured lightning data


Cumulative amplitude distribution Negative polarity

Cloud to ground strikes

2009 – 2016

Optimization of

Lightning detection algorithm

at end 2015

Better detection of

small current lightning

in 2016

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Measured Lightning Data


Cumulative frequency of lightning occurrence IEEE distribution

LLS measurements

I – peak current

IEEE:

M = 31

β = 2,6

LLS:

M = 8.8

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BF3

BF3 slide kao prethodni, samo ima animacijebfranc; 24.8.2017.

Lightning Correlator


Lightning activity close to 220 kV line Konjsko - Orlovac


X CG

X CC

4.5.2009. 15:20h – 17:20h* 10 min interval

LLS spatial correlation


GIS data on transmission network Spatial correlation with lightning data

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LLS time correlation


SCADA data Protection relay pickup, CB tripping, auto-reclosure, definite fault,

etc.

T2

T3 time

CB

tripping

Trip

command

Relay

pickup

Lightning

stroke

≈ 100 - 500 ms≈ 100µs ≈ 18 ms

T1

T0

Event

No.Event Action Time

1. Lightning strike T0

Disturbance propagation along line

from strike location to protection

relay in line bay

≈ 100 µs

2. Protection relay pickup T1

= T0

+ ≈ 100 µs

Execution of relay functions

(overcurrent, short-circuit, etc.

protection)

≈ 18 ms

3. Trip command T2

= T1

+ ≈ 18 ms

CB receives trip command, executes

tripping≈ 100 ms

4. CB trip, opened state T3

= T2

+ 100 ms

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Example correlated data


1 line fault

Multiple lightning flash (5 strokes) 2nd stroke – largest stroke amplitude

LineVoltage

[kV]CB trip time

Lightning stroke

timeTime diff [s]

Stroke amplitude

[kA]

OHL 110 kV 164-RI 11025.08.2013.

20:53:11.276

25.08.2013.

20:53:10.6550.621 -23,1

OHL 110 kV 164-RI 11025.08.2013.

20:53:11.276

25.08.2013.

20:53:10.6860.590 -31,9

OHL 110 kV 164-RI 11025.08.2013.

20:53:11.276

25.08.2013.

20:53:10.7030.573 -7,0

OHL 110 kV 164-RI 11025.08.2013.

20:53:11.276

25.08.2013.

20:53:10.7560.520 -23,6

OHL 110 kV 164-RI 11025.08.2013.

20:53:11.276

25.08.2013.

20:53:10.7770.499 -7,1

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Lightning statistics for Croatian TSO


400 kV 220 kV 110 kV Total

2016

No. of transmission

lines15 27 297 339

Transmission lines

length [km]1 676.225 1 468.082 5 313.616 8 457.923

Alarm zone surfaces

[km2]3 391.696 3 014.185 11 424.409 17 830.290

No. of strokes 91 908 84 993 290 267 467 168

No. strokes / 100 km of

transmission line5 483 5 789 5 463 5 523

Stroke density

[stroke / km2year]27.10 28.20 25.41 26.20

Transmission network 339 lines 110/220/400 kV AC

8 457 km

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400 kV 220 kV 110 kV Total

2016

No. of line bays 33 53 483 569

Total No. of CB

operations390 1 407 10 121 11 918

No. of operations /

No. of line bays20.9 26.5 11.8 20.946

No. of correlated CB

operations3 21 238 262

No. of correlations /

100 km line length0.179 1.430 4.479 3.098

No. of operations

CB due to close

strokes

1 2 54 57

SCADA registered CB operations

CB operations due to lightning

CB operations due to close strokes (near short circuit)

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Isokeraunic level of Croatia


Transmission

region

Number of

correlated CB

operations

Split 146

Rijeka 98

Osijek 12

Zagreb 6

Rijeka

Zagreb

Osijek

Split

17



CB operations due to lightning per voltage level

CB operations due to lightning per transmission region

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Voltage levelNumber of correlated CB

operations

400 kV 3

220 kV 21

110 kV 238

Total 262

Transmission regionNumber of correlated CB

operations

Split 146

Rijeka 98

Osijek 12

Zagreb 6

Total 262

LSAs operation on OHL 110 kV Ston - Komolac


Line lenght: 44 km

110 LSAs – zinc oxide surge aresster installed in July

2007

Configuration obtained by computer simulations Overhead line parameters, grounding tower resistance

Results not applied completely

Modified twice during the first six years of operation

6 LSAs dismantled due to mechanical damages

50 towers with 1 LSA, 24 towers with 2 LSAs and 2 towers with 3 LSAs

I3CM Software


Display of event registered by I3CM transient recorder and corresponding LLS data

Same event registered by several transient recorders

Corresponding LLS data

*type of fault: lightning

*location: near Tower 60

Transient voltages and

currents measurement shapes

Event automatic analysis

I3CM Software


I3CM Transient Recorder

I3CM wall-mounted

Characteristics:

• Installed in the substation secondary equipment cabinet

• Monitoring of 3 voltages and 3 currents for transmission line

• GPS accurate timestamp

• Automatic analysis of the transient event

No need for the line disconnection for the installation!

Indoor GPS

antenna connector

Power Supply

connector

6 BNC connectors

(3 for voltages, 3

for currents)

Network

connection

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110 kV transmission network of the island of Brač

OHL 1

OHL 2


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LSAs installation


OHL 1 – 110 kV OHL Nerežišća – Stari Grad

- Line section lenght: 8.228 km

- 25 LSAs installed

- 3 towers with 1 LSA, 8 towers with 2 LSAs, 2 towers with 3 LSAs

OHL 2 – 110 kV OHL Dugi Rat – Nerežišća 2

- Line section lenght: 5.929 km

- 20 LSAs installed

- 15 towers with 1 LSA, 1 tower with 2 LSAs, 1 tower with 3 LSAs

LSAs – zinc oxide surge aresster:

Uc = 78 kV, Ur = 108 kVeff , IEC Class: II, Nominal discharge current:

10 kA, Discharge current withstand strength (4/10 μs): 100 kApeak

Tower data


Line One-circuit

Tower Steel-frame

Conductors 240/40 - Al/Steel

Shielding wire ACS – OPGW

Rd1 [Ω/km] 0.118

Xd1 [Ω/km] 0.414

R01 [Ω/km] 0.349

X01 [Ω/km] 1.108

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Tower data


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Number of the lightning strokes within the

alarm zones (2016)


29

2 3 2

2840 34

76

25

45

100

101 2 6

8697

13

400

3

123

0 00

50

100

150

200

250

300

350

400

450

1.2016. 2.2016. 3.2016. 4.2016. 5.2016. 6.2016. 7.2016. 8.2016. 9.2016. 10.2016. 11.2016. 12.2016.

Lig

htn

ing s

tro

kes

Months

OHL 1 OHL 2OHL 2 OHL 1

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Total failures of the OHLs and failures caused

by the lightning (2009-2016)


OHL 2 total number of failures OHL 1 total number of failures

OHL 2 failures caused by lightning OHL 1 failures caused by lightning

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Stroke density map [stroke/km2/year] (2009-2016)


Tower

LSA

no LSA

BF1

BF1 nova mapa

- stupna mjesta

- Density CG, 1 decimala

- simboli za stupove s i bez LSA

- legendabfranc; 24.8.2017.

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Stroke density


Low resolution ground stroke density map [stroke/km2/year]

(2009-2016)

- 4.0 – 4.6 flashes/km2/year

- Average stroke multiplicity of 1.592 strokes per flash

- 6.36 – 7.31 strokes/km2/year

High resolution ground stroke density map [stroke/km2/year]

(2009-2016)

- Level of towers exposure to the lightning

- 3.6 flashes/km2/year

- 8.1 strokes/km2/year

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Time and spatial correlation – Case 1(1)


110 kV overhead line 2

Relay protection system data:

Tripping time 23.07.2015. 10:43:05.682

Fault type Definite disclosure

LLS data:

Lightning stroke time 23.07.2015. 10:43:05.553

Lightning current (kA) -34.0 Distance (km) 7.286

Distance 7.286 km - tower number 26

No LSA installed

8.945 flashes/km2/year ground flash

density

Critical current 13.5 kA

Lightning strike to the shielding wire

110 kV OHL 1

OHL 1

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The number of outages due to the lightning has decreased

significantly for the OHL 1 (only one fault in 2015)

No outages occurred on the towers with the LSA installed

Line section without LSAs exposed to the lightning

influence due to its specific location and difficult access to

the towers

Possible installation of additional LSAs to the OHL 1 in next

phase of the project

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Distance 2.194 km - tower number 15

No LSA installed

3.049 flashes/km2/year ground flash

density

Critical current 11.6 kA

OHL 2

110 kV overhead line 1

Relay protection system data:

Tripping time 4.09.2015. 19:59

Fault type Definite disclosure

LLS data:

Lightning stroke time 4.09.2015. 19:59:56.908

Lightning current (kA) -9.7 Distance (km) 2.194

110 kV OHL 2

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For the increased lightning activities the number of outages

of the OHL 2 remained the same

Two of the outages occurred on the towers with the LSA

installed to the bottom phase

Line section without LSAs exposed to the lightning

influence due to its specific location

Possible reconfiguration of LSAs installed on the OHL 2 in

the next phase of the project

Future projects for LSAs implementation

Overhead line sections of transmission lines:

1 - 110 kV Ston-Ponikve equipped with LSAs in

2015

2 - 110 kV Ponikve –Blato on the peninsula

Pelješac and island Korčula

3 - 110 kV Blato – Stari Grad on the island

Korčula and island Hvar

4 - 110 kV Nerežišća – Stari Grad on the island

Hvar

1

2

3

4

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Conclusion


LSA performance during two and a half years after the

installation

Time and spatial correlation of the relay protection system

data and LLS data

Number of outages of OHLs in relation to the lightning

activities decreased

Possible improvements and further analyses needed

Future application to OHLs in the Southern part of Croatian

transmission network

This work has been supported in part by the Croatian Science

Foundation under the project “Development of advanced high

voltage systems by application of new information and

communication technologies” (DAHVAT).

Prof. Ivo Uglešić

Božidar Filipović-Grčić, PhD

Faculty of Electrical Engineering and Computing

University of Zagreb, Croatia


THANK YOU FOR YOUR ATTENTION

Performance of e Line Surge Arresters of e 110 kV Overhead...

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