Overview of External Insulation Monitoring in Combined Harsh Desert, - - PowerPoint PPT Presentation

Overview of External Insulation Monitoring in Combined Harsh Desert, Marine & Industrial Environments

RAOUF ZNAIDI

“OVE VERV RVIE IEW W O Of f EXTERNAL TERNAL IN INSU SULA LATI TION ON MONIT NITORING ORING IN COMB OMBINED NED Har arsh sh DESE SERT RT , M , MARINE NE & INDUST STRIAL RIAL ENVIRONMENTS VIRONMENTS“

By By Raouf uf ZNAIDI AIDI Consult ltant ant, , TUN UNISI ISIA. A.

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I./ Desert & SEA-Coast : With Particular Reference to Their Proportion & Impact on HV Systems in Northern Africa & Middle- East, II ./ External Insulation In Northern Africa & Middle East, Case Studies : STEG –Tunisia Case, GRTE- SONELGAZ Algeria Case, ONEE - MOROCCO Case , KAHRAMAA- Qatar, GCCIA – KSA Case, III ./ Pertinent FIELD OBSERVATIONS & COMBINED PREVENTIVE & PREDICTIVE Measures…

PL PLAN AN OF OF THE HE PR PRESE ESENTATION: NTATION:

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THE SAHARA: The World's Largest Hot Desert Stretching From The Atlantic Ocean to The Red Sea. Called “ Dry Lands“

that Receive < 25 cm of Rain/ Year..

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KNOWN AS “MENA” REGION

(MIDDLE EAST & NORTH AFRICA):

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MOROCCO ALGERIA TUNISIA K S A QATAR ca case e studies udies

External Insulation & Insulation Coordination : Varied Number of Insulators /String/Syst. Voltage

Number Of Insulator Discs/string/Volt Tunisia Algeria Morocco KSA1&2 Qatar 220 400 220 400 220 400 380 400 220 400 Tension Tower 18 A-f 24 A 20 AF 37 A 18 AF, Sir Sir Sir 37 A-F 24A Sir 45A Sir Suspension Towers 16 A-f 23 A

18 AF

Sir. 35 A 18 AF, Sir 24 A Sir Sir 43 Std 21A Sir 45A Sir Unif.Spec.leak.Dist mm/KV.ØØ 58 60 62 68 70

• St. Standard

A:aero Anti-Fog (AF) Sir5

Coastal lines Length & Sahara Desert Proportion In Northern Africa ...

90%

40%

92% 94% 1 622 km

1 298 km

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1 835 km

TUNISIA

MOROCCO

ALGERIA

Ext xternal ernal Insu nsulati lation

• n In

n No Norther thern n Afric rica a : :

ST STEG EG -TUN UNISIA ISIA CASE ASE

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ENERGIZED TEST STATIONS “ETS” LOCATION IN TUNISIA : 18 “E.T.S” Representing Combined

Marine -Industrial/ Desert- Desert/ Desert-Marine- -Industrial Pollution…

3 TEST STATIONS With MONITORING SYSTEM (Ih & METEO. PARAMETERS ): I Goulette: Marine Industrial Pollution II Zarzis: Marine Desert Pollution, III Douz: Desert Pollution

I Goulette: II Zarzis: III Douz:

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Goulette Test station Used as An Optimizing Tool for insulators Selection & Maintenance & for Training Courses...

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Leakage akage Cu Curr rrent ent & Weath ther er Paramet ameters ers Monitoring

• nitoring syst

ystem em.

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Capteurs Météo: Vents, Pluies, UV, H, T° Base de données

Alarme lumineuse

Alarme sonore fusibles capteurs courants

Monitoring system for Leakage Current & Meteo. Parameters Measurements:

• ptimization of

washing & maintenance program.

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OTHER STATIONS: ZARZIS Test Station Marine Pollution ‘Salt Spray…’

Typical Local Test Station: Site Pollution Severity Assessment , “In Contact” Measurements Leads to Accurate ESDD/NSDD ( Avoiding any risk of Pollution losses ).

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Severe Surface Erosion Of Glass Discs & Severe Corrosion of Both cap & Pin Insulators… Due to Severe Combined Sand Blasting & Salt Spray

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Mechanical Deformation & Severe Corrosion Problem experienced on The first 120KN Aerodynamic insulator pin...On 220KV Systems.

GABES- Tunisia.

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13 mm 15,5 mm 16 mm

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THE ADDITION OF AN SACRIFICIAL SLEEVE OR RING BECOME NECESSITY.

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Non Uniform Pollution Distribution On Standard Cap &pin Glass Insulators In Desert Area Is Now Validated By Both Cigré & IEC . (Douz-Tunisia)

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• Ins. Shape

Site Ca Mg Na K Si P Fe zn Stabdard Marine 875 100 800 52,5 16,4 0,6 <1 2,5 Desert 616 33 516 18,5 25 <4 <2 <1

• pen

Marine 550 50 650 35 19,7 <1 <1 <1 Desert 464 16 364 10,9 19,6 <4 <1 <1 Sir Marine 32,5 7,5 100 2,5 17,2 <1 <1 <1 Desert 28 0.8 26,3 1,1 18,6 <1 <1 <1

Chemical Analysis of insulator Contaminants in Desert & Marine environment ( in ppm).

NOTE: Chemical analysis Results have confirmed that local Desert sand contains up to 18% of salt…

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DISTRIBUTION POLLUTION “RATIOS” :

* ESDD/ NSDD = 1/2 to 1/3 . On reference glass insulator * WIND SIDE / LEE SIDE = 1/2 . * TOP SIDE / BOTTOM SIDE = 1/2 to 1/3 . * ESDD TOP SIDE RANGE = 0.1 to 0.4 mg/ cm² . * ESDD BOTTOM SIDE RANGE = 0.2 to 0.7 mg/cm² * ESDD BOTTOM “HV end” SIDE = up to 20% more pollution than other Discs. * ESDD VERTICAL / HORIZENTAL = + 20%

• ESDD REFERENCE / AERODYNAMIC = 2.

Chemical Element Natural Pollution (in %) Tonoko in % According to IEC Kaolin in % According to IEC

Si

25 61 73

Fe

<2 17 1.5

Al

• 14

23

Ca

616

• K

18.5 6.5 _

Mg

33 0.6 _

Na

516 _ _

Ti

• 0.6

1.6

Chemical Analysis of Combined Marine & Desert Natural Pollution Compared to IEC Artificial pollution.! In spite of the last revision Something Should be updated …

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ESDD< 0.30 ( LEVEL I ) ESDD DD 0.30 ( LEVEL II ) ESDD ( mg Nacl /cm2)

KELIBIA MAHDIA EL KEF

TUNISIA

GAFSA SFAX GABES JERBA ZARZIS KEBILI

ALGERIA LYBIA

MONITORING TEST STATION

BIZERTE

POLLUTION MAP Of TUNISIAN NETWORK

ESDD, NSDD , I.higest &

• METEO. PARAMETERS…

UV, Wind, T°, Humidity, Rain

DOUZ

Last Update: 2010.

Goulette

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Ranking By Order of Merit

• f Suitable

insulators For each Area .

KELIBIA MAHDIA EL KEF GAFSA SFAX GABES DJERBA ZARZIS KEBILI

ALGERIA LYBIA

BIZERTE

Insulators Profile Suitability VS Environment

Sir Reg. Sheds Sir Alt. Sheds Anti-fog

Open

Standard

Desert Marine Desert Marine Tension Suspension PROFILE/SHAPE Legend:

Acceptable Unsuitable Suitable

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Ext xternal ernal Insu nsulati lation

• n In

n No Norther thern n Afric rica a : :

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GRTE TE -ALGE ALGERIA RIA CA CASE SE

OVERVIEW of The MOST POLLUTED AREA In ALGERIA… Combined Petrochemical & Industrial & Marine Pollution « Marsat.ORAN ».

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Petroch

• chemi

emica cal plant chimney ney relea easi sing g a perma manent ent 24 24/24 24 H H p per Day ay dark thick sm smoke e

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External Insulation Of 400KV Systems GRTE-ALGERIA case:

37 Aerodynamic Type Tension Glass Discs 34 Aerodynamic Suspension Glass Discs

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Original rTV COaTing in grTE’s subsTaTiOn : On Only y 2/3 of

• f E

Ext xter ernal al Insu sula lation

• n ha

have ve been en COaTEd…

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Pe Pertinent tinent St Study dy : Loc

• cali

alizat zation ion of

• f

ST STOR ORK K Em Emigr gration ation Roa

• ads

ds & Po Popu pulation ation…

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Or Orig igin inal al An Anti-Sto Stork rk Tech chnique ique Adding Ad Additi tion

• nal

al Aerody dynamic ic Insu sulat ator

• r

Cal alled ed « Umb mbrell rella Tech chnique» ique»

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Live ve Line ne Washing shing By y Helic licop

• pte

ter r Is Widely idely Proved ved on n GRET’s HV HV Systems ystems

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Co Costly tly Mounte nted d Live ve Line ne Washin hing g By y grTE’s CrEw in EmErgEnCy CasEs…

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Insulator Test station in ORAN- Western Algeria leading to Validation of Previous Tunisian Field Results. ( Including training of GRTE & CREDEG Working Group )!

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GRTE-SONELGAZ-Algeria Test Station Installed in the most polluted area in Oran (North-Western Algeria) within Periodic In Contact Pollution Measurements & Analysis :ESDD/NSDD. (2006-2008).

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Ranking & selection of Suitable Insulators Profile & Material …ALGERIA Case….

PERTINENT CONCLUSION: Insulators Ranking Results in Oran (Algeria) Confirm & Validate Similar Previous Works Performed in The Same Environmental Conditions in South-Eastern Tunisia Gabès…

AL ALGERIA GERIA

Tunisi sia

Same Ranking Ranking

MOROCCO

Ranking

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Optimum Profile Characteristics

• f Insulators for Severe Dry Pollution.
• Open Profile : Most suitable for pollution type A.
• Standard Insulators: acceptable
• spacing : 146 mm *
• Slope angle : 8° < α <

< 12°,* ,*

• S/P

P Ra Ratio: io: (self lf-cleaning cleaning) ) S/P > 0 > 0.8* 8*

• Cr

Creepag epage dist stance ance fact ctor:

• r: (Lt

Lt/S /St) t) CF CF < < 4** **

• Alternat

ternating ing sheds eds for Si compos mposite ite insulat sulators

• rs,
• E- CR

CR core re ,

• Protec
• tected

ted Interf terface aces, s,

• * Rec

ecomm

• mmend

ended ed for r Heavy avy & & very ry H. Po Pollut ution. ion.

• **

**Lt Lt: total cre reepa epage ge dist stan ance, ce, St: Ar Arc c distanc tance e .

Ext xternal ernal Insu nsulati lation

• n In

n No Norther thern n Afric rica a : :

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ONEE NEE -MO MOROCCO ROCCO CA CASE SE

Early 1990’s Epidemic of Vandalism …leading to

• Stone-throwing

vandalism affecting glass strings in Several regions in Morocco Including Severe Hardware corrosion due to aggressive service environment…

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Ne New Ex Exter ernal nal Ins nsulatio lation n St Strate rategy gy:

Since 2008, ONEE’s external insulation strategy has been that new

• verhead lines at all voltage levels –

including 400 kV – will be insulated mainly with composite insulators, especially in polluted & vandalized* areas. (*) : 1990s were epidemic years of vandalism leading to up to 24 glass discs

• n a single 400 kV string shattered by

rock-throwing…

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 80 percent of outages around Tangiers were due to large Storks population , since 2008 more than 536 special arrangements of composite and glass insulators strings have been installed specifically to protect ONEE systems & Storks against accidental short circuit, According to their progressive use , Morocco has become a leader in North Africa in terms of service experience with composite line insulators,

Ma Main in Oper erat ating ing Proble blems ms & & Fi Field eld Exp xperien eriences: ces:

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Monthly Inspection By Special Electric Field Diagnostic Devices Designed for Polymer Insulators..

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Live Line Washing Still A Basic Option In Polluted areas…

• Live washing of

existing Glass Insulators at ONEE relies more & more

• n Helicopters .

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Pertinent Protection of Both Stork & ONEE’s 60 KV Systems…

• Examples of Special

Stand off insulator string configurations at 60 kV intended to Both Protect Birds & limit accidental short circuit by storks…

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The Need to Find Palliative technique for Both Storks & line Outages …

• Outage triggered by

electrocution of stork in spite of the additional anti-stork composite insulator in Diagonal position.

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Ext xternal ernal Insula nsulatio tion n In In MID MIDDLE DLE EAST T : :

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Qatar tar -Kahr ahramaa amaa CA CASE SE

Extern ternal al Insu sula lation

• n In Qa

Qatar ar Reli lies es On On Bot

• th

h NCI & R RTV V Coa

• atED

ED Glas ass s Insu sulat ators

• rs

Up to 45 aerodynamic RTV coated Glass discs for 400KV Systems…

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• Ov

Over insu sula lation

• n an

and

• v
• ver-desi

design gn of

• f

220 220KV KV tow

• wer

Ha Has r s resul sulted ed in up to

• 542 Coa
• ated

ed ae aerod

• dyn

ynam amic ic- glas ass s insu sula lators

• rs

wit ith h a T a Tot

• tal

al com

• mbined

ned weight ht of

• f

4320 4320 kg.

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• the whole

process of application of the RTV silicone to insulators is completely Achieved & Monitored in a local paint workshop in Qatar!

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Ext xternal ernal Insula nsulatio tion n In In MID MIDDLE DLE EAST T : :

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GCC CCIA IA –KSA SA CA CASE SE

Exter ternal nal Insulation nsulation GCC CCIA IA-KSA KSA ca case se:

Up to 43 anti-fog Glass discs for 400KV Suspension Towers

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“ExpEctEd” BuriEd towEr FEEt…

Frequent Sand Storms leading to Undesirable Sand Dunes Which Follow Dynamic Wind Turbulence Effect…& Accumulation Mechanism…

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JUBAIL In EASTERNAL KSA: : …All mixed Pollution sources, Petrochemical, Industrial, Steel Plant, salt plant…

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Immersed Tower Feet Around Salt Lakes..

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Salt lakES along thE SEa coaSt…

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Integrity of Ground footing Structure & Foundation..close to salty Soil & Lake… Should be periodically Inspected.

Diagnostic of Tower & Foundation & Permeability due to Salt Water Absorption by capillarity phenomenon,

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Not to be Missed Galvanization Measurements…

Regular Galvanization thickness Measurements of cap & pin Insulators & tower Hardware as Preventive Measures for preventing early corrosion…

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Zinc & RTV. Coating Thickness Measurements.

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Cap & Pin Galvanization Measurements ...

Insulator Type Cap Pin* ( with Zinc sleeve)

G 1.e

189/220µ 106µ

G5.e

180 113

G2.e

104 125

G3 Int.

186/79 81/ 155

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Heavy Logistics Dedicated to The First “In Contact” ESDD Measurements On 400KV System

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First In-Contact “ESDD” Measurement

• n GCCIA

400KV System In Eastern KSA..

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In n Co Cont ntact act ESDD/NSDD SDD/NSDD Measurement easurements: s: Rapidity pidity & Preci cisi sion

• n.

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Site Pollution Severity Estimation Method:

1/ ESDD Equivalent Salt Deposit Density &

2/ NSDD Non-Soluble Deposit Density

Top Bottom

Salt Deposit Density ESDD Non-Soluble Deposit Density NSDD

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200 CC Demineralized Water.

Site Pollution Severity Estimation: Ground ESDD/NSDD Measurements.

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No Transfert of Hydrophobicity to Pollution Contaminants!

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Pollution Contaminant was for this case carefully wiped from total Down surface.

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ESDD, NSDD, Galvanization & RTV Coating Thichness & Wettability Measurments Results

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SITE POLLUTION CLASSES “ Type A”:

All These measurements are leading to a Site Pollution Severity (SPS)

• class. NSDD= 1.665 mg/cm² (e).

ESDD=0.348 mg/cm² (d)

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TYPE A

Chemical Analysis Of Pollution Contaminants (Residue)

Cations

mg/l Al Ca Fe K Mg Na S.

sulfu

Si Sr Zn Ti

titan

342 1000 193 64 387 19 930 3.4 3.8 17.5 6.3

Anions

mg/l

SO4² Sulfate Cl- Chlorid NO3 nitra 1249 356 749

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Chemical Analysis Of Soil Samples ( Sand) & Salt Water.

Cations

g/Kg Al Ca Fe K Mg Na S.

sulfu

Si Sr Zn Ti

titan

Sand

2.9 53.3 3.7 0.5 9.8 46.3 18.1 0.09 3.8 0.11 0.18 Anions

SO4² Sulfat Cl- Chlorid NO3 nitrat

Salt Water

3386 6329 <<

Sr: Strontium S: Sulfure Ti: Titanium

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AC ACTIVE IVE & I & INE NERT RT POLL LLUTIO UTION

 Active Pollution ( conductive layer)

Conductive pollution



Gasses in solution: SO2, H2S, NH3..

 High solubility salts

– Salt Spray,

 NaCl, MgCl, NaSO4,  Bird Streamer (10-30 mS/cm)

– Low solubility salts : CaSO4, Mg SO4,

 Gypsum, Cement…

 Inert Pollution

(Influence conductive layer)

– Hydrophilic pollution

 Kaolin, clay

– Hydrophobic Pollution

 Silicone grease

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HIGH & LOW SOLUBILITY POLLUTION PROPERTIES:

LOW SOLUBILITY SALTS HIGH SOLUBILITY SALTS FAST DISSOLVING SALTS MgCl2 , NaCl SLOW DISSOLVING SALTS MgSO4, Na2SO4, CaSO4 NaNO3, Ca(NO3)2, ZnCl2

1

Conductive & Active Pollution Types :

CONDUCTIVE POLLUTION CONDUCTIVE After DISSOLVING

Metallic deposits such as Magnitite, Pyrite; Gasses in solution: SO2, H2S, NH3 Salt Spray Bird Streamer  Ionic Salts: NaCl, Na2CO3 MgCl2, gypsum CaSO4 Others, Fly ash, cement

2

SITE POLLUTION SEVERITY & POLLUTION CLASSIFICATION “ Type A”:

• I/ Pollution Classification:
• Pollution can generally be classified as one of two types A or B:

Type A (Solid) pollution and

• Type B (fog, rapid) pollution.
• According to all achieved ESDD and NSDD measurements

Completed with Chemical Analysis of Pollution Contaminants The Deposited Pollution Generally Consists Of soluble and non- soluble components.

• This Confirm Pollution classification as “Type A”.

3

WETTABILITY CLASSES. IEC. 62073.TS 1 2 3 4 5 6

4

WETTABILITY TESTS.

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RTV Coating Ageing? Hydrophobicity Class HC:4 & 5… After just 5 Years In service…

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Wettability Class of a New Coated Glass Insulators as Reference!

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Wet ettab tabilit ility Test Test Resul esultS tS

Insulator Type

Wettability Classes Up/Down

Observation G 1.e

4/4

RTV Coating damage

G2.e

5/4

Apparent peeling On upper surfaces

G5.e

5/4

G3 Int.

6/7

G2.int

5/6

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Light to Severe Damage of RTV Coating Including frequent Peeling….

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Adhesion Test 2: 100 Hours Boiling water According to IEEE Standard 1523

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Apparent light growing Bulbs Observed After 100 Hours…

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RTV Silicone Coating Adherence Tests: I/ Cross Cut Of Adhesion Tests On Both New & Naturally aged Insulators According to ASTM D. 3359-2002.

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& On RTV Coated cap & pin Glass Insulator …After 6 years in Service! Al-Fadhili

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& On Naturally Aged RTV Coated cap & pin Glass Insulator after 5 years in Service in Other Location.

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Self-Shattering Of Glass Insulators

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Pin Bending…due to imProPer mechanical dimensioning …

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St Star art of

• f C

Cor

• rrosi

rosion

• n Me

Mecha hanism nism In sp spite e of

• f

AD ADDIT ITION IONAL AL Sa Sacri crifi fici cial al Zi Zinc Sl Sleeve! eeve!

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Pil ilot

• t

Te Test t Sta tation tion in in Dam amma mam

• KS

KSA

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Wind Rose: To Provide Scientifically Prevailing Wind Direction for Test Station Orientation …

Confirmed by the Natural Leaning of the Wild Plant Under Prevailing Wind Effect. Just Beside Fadhili Test Station…

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For Our Case studies, It was proved that All built Tests stations in Northern Africa have notably proven to be a good investment for Both Tunisian utility STEG ( 18 + 3 Energized & Monitoring Test Stations) & Algerian- GRTE and lastly GCCIA-KSA since they have allowed:

• A Good field training of all Engineers & technicians involved in

the Design & Operating of Both MV & HV Systems,

• A Good understanding of external insulation & service

experiences of Different Types of Insulators in different polluted conditions,

• To Establish and/or to update the pollution -Map of the Electrical

Network,

CONCLUSIONS:

• To select suitable insulator design &

material for each type of environment,

• To detect poor design weakness in a

relatively short testing period,

• To determine how often and when line

insulators would have to be washed,

• To save at least 30% of the total washing

cost/ year routinely programmed …,

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….2/3

IV/ ARTICLES & INTERNATIONAL PUBLICATIONS & REFERENCES Of The Consultant:

2015: “Expanded Test Station helps Greek Power System Operator Assess Insulator Design & performance”. INMR

• journal. Issue 107.Q.1.2015.

2014: “400 KV Super-grid with Modular HVDC System Interconnects Countries of Arabian Gulf. INMR Journal. Issue 103.2014. 2013: “Artificial Pollution Test for Polymer Insulators”. Cigré Working Group C4.303. Co-author. 2013: “Outdoor Insulation in polluted Conditions: Guidelines for selection & dimensioning. Part.2: The DC Case. ” Cigré Working group C4.303. Co-author. 2013: ”Moroccan Power Utility adjusts Priorities to new Network Challenges” INMR Journal.Issue 98.Q4.2012. 2012: ” Algerian Grid focuses on challenges of Harsh Service Environment” INMR journal. Issues 96 & 97 Part 1 .Q2.2012 & Part II. Q3. 2012. 2012:”Turkish Transmission Utility Looks to silicone Insulators to Reduce Construction & Maintenance Costs”.

• INMR. Journal.Q.1.2012.

2011: “Qatar Power Grid faces Combined Challenges of Pollution & Rapid Expansion”. INMR journal.Q.2-2011. 2011:”Impact of desert Marine Pollution on External Insulation” 2011 INMR World Congress. Seoul. Korea. 2011: “Outdoor Test Station: Optimizing tool for Insulator selection & Maintenance”. 2011 INMR World Congress. Seoul. Korea. 2010: “Selection of optimum Profile in Polluted Environment”. Cigré Regional Meeting. 9 & 10 February. Tunis.

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2009: “Performance of HV ceramic & non ceramic insulators under combined Marine & Petrochemical Pollution in North –West Algeria” .2009 INMR World Congress. Crete. Greece. 2008: « Outdoor Insulation in Polluted Conditions: Guidelines for selection & dimensioning » Cigré technical Review. N° 361. "Co-author". 2005: « Service experience & maintenance requirements for different types of insulators in Tunisia ». R.

• ZNAIDI. 2005 INMR World Congress. Hong Kong. China.

2005: “Optimization of washing insulators program in polluted areas in Tunisia”. R. ZNAIDI. Arab Cigré symposium.. Cairo. Egypt. 2001: “ Recherche de corrélation entre la pollution artificielle et la Pollution naturelle dans un milieu marin & désertique en Tunisie ». R. ZNAIDI. Cigré Symposium. Cairns. AUSTRALIA. 2001:” Assessment of composite insulators behavior in marine & desert Environment” R. ZNAIDI.

• CIHVI. International symposium. Heraklion. Crete. GREECE.

2000: “Field & laboratory testing for the choice of optimum composite Insulator design for a Marine– Desert environment” R. ZNAIDI & Al. Cigré General Session. Paris. France. 2000: “POLLUTED INSULATORS: A REVIEW OF CURRENT KNOWLEDGE” R. ZNAIDI. Cigré Technical

• review. N° 158. "Co-author".

1999: “Research & Assessment of insulators performance in marine & desert Environment”. R. ZNAIDI. World Congress on insulator technologies for The year 2000 & beyond” INMR. Barcelona. Spain. …

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REFERENCES: CIGRÉ Guidelines

• Polluted insulators: A review of current knowledge

Technical brochure 158, June 2000. Co-Author.

• Polluted insulators: Guidelines for selection and

dimensioning

– Part 1: General principles and the a.c. case Technical brochure 361. June. 2008. Co-Author. – Part 2: The DC. Case: Technical Brochure N°518. December 2012 . Co-Author.

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Thank you … Merci... Спасибо 及物动词 Tack Vielen Dank 감사합니다 Grazie …لي زجلا ركشلا عم

Raouf ZNAIDI.

• October. 2015.

raouf_z@yahoo.com

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