High Voltage Electrical Equipment Failure Diagnosis · High Voltage Electrical Equipment Failure Diagnosis ... High Voltage Electrical Equipment Failure Diagnosis ... E.P.D. at 132kV

High Voltage High Voltage Electrical Equipment Electrical Equipment

Failure DiagnosisFailure Diagnosis

Presented by:Spencer Tang & Terence Ng

T&T Inspection & Engineering Sdn Bhd

Ultrasound World VII 2011Ultrasound World VII 2011 22

High Voltage Electrical Equipment Failure Diagnosis

Definition of High Voltage (H.V. / H.T.)Definition of High Voltage (H.V. / H.T.)–– According to IEC standard, According to IEC standard,

High voltageHigh voltage is defined as those with more than is defined as those with more than 1000V (>1000V AC) for 1000V (>1000V AC) for alternating current alternating current low voltagelow voltage (50~1000V AC) and (50~1000V AC) and extraextra--low voltagelow voltage(<50V AC) circuits, in the context of building wiring (<50V AC) circuits, in the context of building wiring and the safety of electrical apparatus.and the safety of electrical apparatus.

–– In South East Asia, HV is ranging from In South East Asia, HV is ranging from 1kV (1000V), 3.3kV, 6.6kV, 11kV, 22kV, 1kV (1000V), 3.3kV, 6.6kV, 11kV, 22kV, 33kV, 132kV, 230kV, 275kV, 400kV & 500kV. 33kV, 132kV, 230kV, 275kV, 400kV & 500kV.


Map of the Map of the AseanAsean



Characteristic of High VoltageCharacteristic of High Voltage–– Higher voltage required higher insulation level Higher voltage required higher insulation level –– Ability to penetrate insulation material (air, Ability to penetrate insulation material (air,

vacuum, gas, oil, XLPE, PILC, porcelain, etc) vacuum, gas, oil, XLPE, PILC, porcelain, etc) due to deterioration / aging / interruption / due to deterioration / aging / interruption / human error, etc and create short circuit / human error, etc and create short circuit / discharge between phase to phase / phase to discharge between phase to phase / phase to groundground

–– resulting severe facility damage / loss, injury / resulting severe facility damage / loss, injury / deathdeath



NDT Technology of UltrasoundNDT Technology of Ultrasound–– a method to detect HV fault symptom a method to detect HV fault symptom

(electrical partial discharge (electrical partial discharge –– E.P.D.) from a E.P.D.) from a safesafe distancedistance

–– Provide safeProvide safe accessaccess via structure borne and via structure borne and airborne method without direct expose to the airborne method without direct expose to the live part / component.live part / component.

–– HighlyHighly sensitivesensitive ultrasound instrument ultrasound instrument coupled with coupled with qualifiedqualified inspector will able to inspector will able to detect HV fault symptom (detect HV fault symptom (egeg: corona, : corona, tracking, arcing, mechanical looseness and tracking, arcing, mechanical looseness and etc)etc)


E.P.D. at 33kV VCB E.P.D. at 33kV VCB –– Cable VOIDCable VOID

Cable insulation void at cable compartment Cable insulation void at cable compartment


E.P.D. at 33kV VCB E.P.D. at 33kV VCB –– Cable VOIDCable VOID

Cable insulation void at cable compartmentCable insulation void at cable compartment

2007

Jul 2008

Oct 2008


E.P.D. at 33kV VCB E.P.D. at 33kV VCB –– BusbarBusbar

BusbarBusbar insulation deterioration insulation deterioration –– corona corona partial dischargepartial discharge


E.P.D. at 33kV VCB E.P.D. at 33kV VCB –– Breaker ContactBreaker Contact

Chemical reaction on conductor Chemical reaction on conductor


E.P.D. at 132kV Lightning ArresterE.P.D. at 132kV Lightning Arrester

Internal partial discharge at porcelainInternal partial discharge at porcelain


E.P.D. at 33kV Overhead Disc IsolatorE.P.D. at 33kV Overhead Disc Isolator

Airborne detected PD at disc isolator Airborne detected PD at disc isolator suspension clamp suspension clamp –– sharp edges/ sharp edges/ oxidization / deterioration oxidization / deterioration



mechanical vibration / looseness in HV mechanical vibration / looseness in HV breaker causes bybreaker causes by–– the resonance of electrical frequency (50Hz / the resonance of electrical frequency (50Hz /

60Hz) or electrical harmonics60Hz) or electrical harmonics–– workmanship issue during on site installation workmanship issue during on site installation

((egeg: tightening / torque, panel and floor : tightening / torque, panel and floor leveling, greasing, etc)leveling, greasing, etc)

–– Operator ignorant or mechanism error (Operator ignorant or mechanism error (egeg: : breaker misalignment, breaker arm bent, breaker misalignment, breaker arm bent, shutter jammed, etc shutter jammed, etc


Mechanical vibration / looseness in HV breakerMechanical vibration / looseness in HV breaker

Looseness detected at breaker & Looseness detected at breaker & busbarbusbar



Repair urgency on partial discharge Repair urgency on partial discharge detected:detected:–– Rate of deteriorationRate of deterioration–– Location of the PD detectedLocation of the PD detected–– Loading fluctuation Loading fluctuation -- on/off, surge start, peak on/off, surge start, peak

loadload–– Surrounding environment condition Surrounding environment condition –– seaside, seaside,

chemical industry, dusty areachemical industry, dusty area……–– External factors External factors –– animal, human erroranimal, human error……


Repair urgency on PD detected

11kV CT flashover during breaker surge 11kV CT flashover during breaker surge start after maintenance due to ignorantstart after maintenance due to ignorant



Dusty and salty environment induced Dusty and salty environment induced speedy deterioration at 33kV VCBspeedy deterioration at 33kV VCB



High moisture environment induced High moisture environment induced oxidization & chemical reaction oxidization & chemical reaction



PD chemical effect on metal panel PD chemical effect on metal panel

Before After



Close PD location increase rate of Close PD location increase rate of deteriorationdeterioration



External factorExternal factor–– Minor corona partial discharge give way in 7 days due Minor corona partial discharge give way in 7 days due

to road constructionto road construction



Client common question to inspector:Client common question to inspector:How long does the PD symptom can last before it How long does the PD symptom can last before it flashover??flashover??

Can we arrange shut down after our production Can we arrange shut down after our production peak time, may be about 6 months later??peak time, may be about 6 months later??

Should we shut down by tonight?? Should we shut down by tonight??


Perfect match of Ultrasound and Thermography

Ultrasound (US) Ultrasound (US) –– hear what we cannot hear what we cannot hear; hear; ThermographyThermography (IR) (IR) –– see what we see what we cannot see.cannot see.–– Technology limitation but not weakness.Technology limitation but not weakness.

Integration of US & IR will supplement the Integration of US & IR will supplement the survey findings and produce a better survey findings and produce a better diagnosis result diagnosis result



11kV RMU required immediate attention11kV RMU required immediate attention

Sp1:temp 32.0

26.0

39.0 °C

30

35

y

Ar1:max 34.5

26.0

39.0 °C

30

35

y



Localizing the fault areaLocalizing the fault area

29.0

40.0 °C

30

32

34

36

38

F LI R Sys tem s

Ar1:max 67.6

Sp1:temp 44.6

25.0

70.0 °C

30

40

50

60

FLIR Systems



Localizing the fault areaLocalizing the fault area

27.0

31.9 °C

28

30

Ar1:max 36.1

24.0

39.0 °C

25

30

35

y



NDT technology ease the inspector / owner to NDT technology ease the inspector / owner to visualize & localize the faultsvisualize & localize the faults

How is the HV partial discharge look like in our How is the HV partial discharge look like in our visual view???visual view???–– TxTx HV corona ring; HV corona ring;

Ar3:max 30.5

Ar1 :max 40.1

Ar2:max 40.2

19.0

43.0 °C

20

30

40


TxTx HV Cable HV Cable -- corona ring partial dischargecorona ring partial discharge


TxTx HV bushing partial discharge HV bushing partial discharge


TxTx HV bushing partial discharge HV bushing partial discharge

Ar1:max 46.1

Ar3:max 44.3

Ar2:max 49.1

38.0

50.0 °C

40

45


Electrical partial discharge effect to plant/climberElectrical partial discharge effect to plant/climber


HV flashover



To conduct a safe and effective inspection To conduct a safe and effective inspection on high voltage electrical equipment, we on high voltage electrical equipment, we should well understand and aware on:should well understand and aware on:–– The safety measure of the HV equipment to The safety measure of the HV equipment to

be inspected;be inspected;–– Our NDT instrumentsOur NDT instruments’’ strength and limitation;strength and limitation;–– Be observant and sensitive to the onBe observant and sensitive to the on--site site

condition of the HV equipment;condition of the HV equipment;–– ““a careful inspector will live longer than a hero a careful inspector will live longer than a hero

(fool) in HV electrical system(fool) in HV electrical system””


230kV GIS230kV GIS

:max 30.8

:max 32.8 :max 30.7

25.0

46.0 °C

30

35

40

45

FLIR Systems

25.0

46.0 °C

30

35

40

45

FLIR Systems


230KV GIS 230KV GIS

:max 30.9 :max 32.8

25.5

46.0 °C

30

35

40

45

FLIR Systems


3MVA 3MVA PauwelsPauwels TrafoTrafo




Glad to share with you,Glad to share with you,

Thank youThank you

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High Voltage Electrical Equipment Failure Diagnosis · High Voltage Electrical Equipment Failure Diagnosis ... High Voltage Electrical Equipment Failure Diagnosis ... E.P.D. at 132kV