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12/2/2011
1
TRANSFORMER CONDITION MONITORING
BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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TYPES OF TRANSFORMER FAULT
• Phase-ground faults - from winding to core or winding totank
• Phase-phase faults - between windings• Interturn faults - between single turns or adjacent layers
of the same winding• Arcing contacts• Local hotspots caused by shorted laminations• External faults causing thermal or mechanical damage• Overloads
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TYPES OF TRANSFORMER FAULT
• Low level internal partial discharges (moisture ingress or design problems)
• Bushing faults (internal to the tank)• Tapchanger faults (often housed in a separate
tank)• Terminal faults (external to the tank, but inside
the transformer zone)
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Role of the Transformer
No Transformer No Power Delivery
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Impact of Transformer Failure
No Power Delivery = Loss of Revenue $$$Power may have to be purchased to meet
contractual obligations $$$Direct Replacement Cost $$$
Bad Publicity & Environmental Damage
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Typical Utility Transformer Fleet
Approx 60% are >35yo(End of Life region)
Approx 8% are <10yo
(Design Flaw Region)
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Transformer Failure
There are 3 types of Transformer Failure: 1. Sudden/unexpected due to outside
influences 2. Design flaw3. End of Life
Failure risk can be reduced by monitoring the Transformer Condition
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Predicted End of Life Failure Rate
Failure distribution for a fleet of Transformers installed between 1964 and 1992
Significant Rise in
# of Failures
Source: William H Bartley & Rowland I James Jr.
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Transformer Users’ Pain{ evaluation from beg of 2000’s }
There were typically 730 transformer fire and explosions per year in the USA.
Many experts anticipate that this number to go up from 1% at beginning of 2000’s to 2% after 2010.
The emphasis on renewable will put more burden on the existing Transformers
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Why do Transformers Explode?A growing concern for Corporate Risk Managers and Insurance Companies
Transformers are considered by Corporate Risk Managers and Insurers as the most critical equipment inside plants because of • the large quantity of oil • in contact with high voltage elements.
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Why do Transformers Explode?Loose international transformer norms and lack of regulation
The Norm IEC 76 only includes basic electrical measurements and does not cover mechanical design or protection. By comparison, pressure vessels have to comply with adequate rules and controls. Such directives do not exist for transformers that have proven to be more dangerous
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Why do Transformers Explode?Transformer electrical and mechanical protection limits
• Pressure Relief Valve inadequacy: pressure gradients developed during low impedance faults are too fast for mechanical devices. All transformers that have exploded have been protected with Pressure Relief Valves.
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Why do Transformers Explode?Transformer electrical and mechanical protection limits
• Buchholz and Rapid Pressure Relay inefficiency:• Transformer electrical protections are not
designed to react to sharp pressure gradients. • During the 62 Transformer Protector tests, the
Buchholz always failed to detect any gas and oil movement or pressure variation.
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Why do Transformers Explode?Transformer electrical and mechanical protection limits
Electrical Breaker opening time:• the best breaker technology trips in 50 ms• far too late to prevent the explosion, • which occurs 10 to 50 ms after the low
impedance fault.
Additionally, the tank pressure
keeps increasing after breaker opening
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Transformer Monitoring can Mitigate……
1 Transformer / FAILURE
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BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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Varioussystems
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Temperature Monitor• Every 6° to 8° C rise in operating temperatures,
the expected life of the transformer will go down by half
• These temperature build-ups cause localized area of high heat and paper damage, followed by events of partial discharge .
• One needs to have a long term trending of the operating temperature inside the transformer.
• Should be performed distributed temperature sensing of all the windings
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Overtemperature Monitoring
Two temperatures must be monitored:
> Winding temperature (‘WT’) - this can rise rapidly, without much of an increase in oil temperature
> Oil temperature (‘OT’) - this can rise slowly to a critical point without an unacceptable windingtemperature increase
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Typical alarm and trip levels(dependent on asset management policy)
• winding alarm - 90ºC to 110º C• winding trip - 110ºC to 135ºC• oil alarm - 80ºC to 95ºC• oil trip - 95ºC to 115ºC• Oil trip may be disabled if transformer is
readily accessible by maintenance crews – on the grounds they can visit sub and may beable to remedy problem this is a controversial practice.
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Temperature vs life
• Economic gains are possible from short time overloads - “life used” calculations may permithigher temperatures for short periods, but WTtrip needs to be more complex or monitored
• 110 ºC winding hot spot temperature gives‘standard’ 20-25 year life of insulation
• Roughly every 7 ºC increase in temperaturedoubles the rate of loss of life for paper in oilinsulation
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END WINDING TEMPERATURE SENSING
By incorporating fiber-optic sensors into transformer windings temperature data can be used to monitor for hot spots within the transformer and to provide ratings based on safe operating temperatures. Alternatively, a fiber-optic cable can be installed after the windings have been wound on the core, or fiber-optic point sensors can be placed at strategic locations.
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FO Cable part of Distributed Temperature Monitoring
BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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Varioussystems
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How about Vibration monitoring
There are significant differences in the low frequency vibration signal amplitudes and frequency content, dependent on the degree of winding looseness.
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Low frequency vibration measurement..... symptoms:
I. Detection of significant difference in low frequency response,
II. Shift of existing resonance, III. Creation of new resonance, IV. Change in shape of various plots would potentially
indicate mechanical or electrical problem with I. the winding and II. transformer core
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Vibration Severity Criteria for Transformers{velocity sensor data - Eng units: ips }
Started with the following overall levels.0.25-.50 ips-…Minor
0.50-.75 ips-… Intermediate Watch list (further investigate)
0.75-1.0 ips-… Serious Look for oil leaks, hot metal gasses and increasing sound levels.
1.00 ips or greater-…Critical Oil leaks, gas generation rates and hot spots.
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Vibration Severity Criteria for Transformers {velocity sensor data - metric units: mm/s }
Started with the following overall levels:
4,5 – 9,0 mm/s-…Minor
9,0-13,5 mm/s -… Intermediate Watch list (further investigate)
13,5-18,0 mm/s -… Serious Look for oil leaks, hot metal gasses and increasing sound levels.
> 18,00 mm/s -…Critical Oil leaks, gas generation rates and hot spots.
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Vibration Severity CriteriaAlarm Parameters for Transformers [ips]
Nominal Freq / Hz Frequency / Hz Label Name Warning Alert Danger
5 to 115 Sub-sync 0.05 0.1 0.25
120 115 to 125 One Times 0.25 0.5 1.0
125 to 235 1st Odd 0.1 0.2 0.3
240 235 to 245 Two Times 0.15 0.25 0.5
245 to 355 2nd Odd 0.1 0.2 0.3
360 355 to 365 Three Times 0.15 0.25 0.5
365 to 375 3rd Odd 0.1 0.2 0.3
480 375 to 485 Four Times 0.1 0.2 0.3
485 to 1000 Hi End 0.1 0.2 0.3
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Vibration Severity CriteriaAlarm Parameters for Transformers [mm/s]
Nominal Freq / Hz Frequency / Hz Label Name Warning Alert Danger
5 to (2*fLINE – 5) Sub-sync 0.9 1,8 4,5
2*fLINE(2*fLINE – 5) to (2*fLINE + 5) One Times 4,5 9,0 18
(2*fLINE + 5) to (4*fLINE – 5) 1st Odd 1,8 3,6 5,4
4*fLINE(4*fLINE – 5)
to (4*fLINE + 5) Two Times 2,7 4,5 9,0
(4*fLINE + 5)to (6*fLINE – 5) 2nd Odd 1,8 3,6 5,4
6*fLINE(6*fLINE – 5)
to (6*fLINE + 5) Three Times 2,7 4,5 9,0
(6*fLINE + 5) to (8*fLINE – 5) 3rd Odd 1,8 3,6 5,4
8*fLINE(8*fLINE – 5)
to (8*fLINE + 5) Four Times 1,8 3,6 5,4
(8*fLINE + 5) to 1000Hi End 1,8 3,6 5,4
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Where to measure the vibrationsHIG H SIDE
SIDE #2
SIDE #4
H ILO
25C
X X
X
X
SIDE #3
LTC
X XX
X
Eight readings ~ Approx 1,6 m from “bottom of core”, and 45 cm from corner
Shell Form
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Where to measure the vibrations
High Voltage Side
Side 1L Side1R
Side 2L
Side 2R
Side 3R
Side 4R
Side 3L
Side 4L
0.15@240
0.09@360 0.22ips
0.9ips
0.05ips
Overhead View of Transformer
Snd=80db
AE=35Cts
Snd=78db
AE=30Cts
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BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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Major Failure Mechanisms
Aging of paper
Moisture in oil
Looseness –movement of the windings
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For the Aging of PaperThe occurrence of PD reveals the existence of dielectric insulation problems within the circuit breaker and the windings. Typically the higher the emitted power and frequency of occurrence, the higher the chance of failure by dielectric breakdown. PD can be measured:
- On-Line or - Off-Line.
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Electrical PD diagnostic techniquesPD measuring circuits according to IEC 60270
a) coupling device in series with the coupling capacitor b) measurement at a bushing tap
Components:AC voltage source U, optional blocking impedance Z, coupling capacitor CK, measuring impedance Zm, a measuring instrument M and generalized test object Ca.
[König, 1993]
frequently used circuit in test laboratories
often applied in on-site/on-line PD investigations
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Electrical PD diagnostic techniquesPD Measuring Impedance for Bushing Tap Installation
500 kV Transformer Bushing
Decoupling of PD signals from the bushing tap
in a wide frequency range up to 30 MHz
Lower cut-off frequency < 60 kHz
Additional voltage signal for phase-resolved
measurements
Superimposed PD and test voltage signal
Very fast and safe over-voltage protection
TNC-socket for signal output
Special feature for continuous PD monitoring
(IP 68)
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Electrical PD diagnostic techniquesAdvanced solution: ACOUSTIC EMISSION added
Acoustic methodElectromagnetic (UHF) method
measuring system
Sound field (acoustic wave)
Piezo-Sensor
PD (partial discharge)
)))))) ))))))
)) ) )) )
) ))) ))
measuring system
))) Electromagnetic wave
example sensor „monopole“
Key characteristics:
non-destructive on-line application of the sensors (no bushing tap necessary)immunity against a wide range of disturbing signals on-site (e.g. corona)
no apparent charge information is delivered so far PRPD patterns possible short arrival timesgeometric PD location possible
very low attenuation in oil and solid insulationsignal attenuation depends on PD site
very low noise level („faraday´s cage“)in principle immun against electric noises
non-destructive on-line application of the sensors (no bushing tap necessary)immunity against a wide range of disturbing signals on-site (e.g. corona)
no apparent charge information is delivered so far PRPD patterns possible short arrival timesgeometric PD location possible
very low attenuation in oil and solid insulationsignal attenuation depends on PD site
very low noise level („faraday´s cage“)in principle immun against electric noises
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IEC 62478 - IEC Proposal, now already Draft level"Non-conventional PD-measurements"
In the past few years, there has been the development of many so-called non-conventional PD measurement methods. Partial discharges (PD’s) generate pressurewaves, sound, light and electromagnetic waves. These physical effects can be detectedby different sensors and so there is the possibility to detect PD’s with non-conventionalmethods besides the conventional electrical measurement. The main method for PDmeasurement is electromagnetic (HF/VHF/UHF) and acoustic measurements. Also,there have been a lot of papers published using these methods. Therefore, IEC TC42 hasin the meeting of September 1st, 2005 in Beijing, decided to proceed with this new workitem called “Measurement of PD’s by electromagnetic (e.g. UHF) and acoustic methods”and to form a new working group for this task. (......)
The task of this new WG is to collect all the used applications of these methods tocompare them with each other and to look at their frequency range. Anotherdifferentiation of the measuring technique is if it is a narrow bandwidth or a wide bandfrequency measurement technique. This work will also include the use and thetechniques of the different sensors, their frequency range and their sensitivity. Also, itwill investigate the issue of the methods, the possibility of PD location and if acalibration or in minimum a sensitivity check is possible. The WG will start with theelectromagnetic methods and after finishing will move forward to the acousticmethods.
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System Check for UHF (on transformers)
Performance Check • Functional check of the whole measuring path including sensors and partial discharge (PD)
acquisition system• not necessarily transmission of electromagnetic waves through the test object , „one-port“
solutions are possible
Sensitivity Check • Emission of electromagnetic waves into the test object necessary and known distance between
sensors and injection location • Pulse Generator injection necessary to determine relation between the apparent charge (pC)
and measured quantities (e.g. V,W,J) through simultaneous measurement • „one-port“ solutions might be possible in relation to the wave length (for compact objects, not
for extended objects)
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Instruments classification based on Bandwidth
Frequency Domain Measurement Time Domain Measurem.Class
Mode Zero Span Full Spectra Ultra Wide Band
FrequencyBand
PDPattern
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Advanced tools for PD monitoring – Electromagn. PD TestsCone-shaped active drain valve UHF-sensors
for the decoupling of electromagnetic PD signals
from the inner of an oil-paper-insulated
transformerPD-signals in the UHF frequency range
(mainly 300 MHz – 1 GHz)
sensors support „Performance/Sensitivity Check“ (high-frequency test impulses can be injected
with additionally integrated electrode)
sensor head is grounded (for lower frequencies)sensor application at oil valves, which are
available e.g. for oil filling or draining (liquid
tightness is tested for 120°C warm oil with 5 bar compression)
View from inside the transformer
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Type-Test Cone-shaped active drain valve UHF-sensors
Oil pressure estimation Combined temperature/pressure test
BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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Alternatives of arrival time based positioning
electro-acoustic
(test laboratory or on-site/off-line)
electromagnetic- acoustic
(test laboratory or on-site, off-line or on-line)
1. Mixed-acoustic methods:
all-acoustic
(test laboratory or onsite, off-line or on-line
with reduced sensitivity)
2. All-acoustic methods:
electrical PD
sensor 1sensor 2sensor 3
t
electrical PD
sensor 1sensor 2sensor 3
tt
)z ,y ,(x s1s1s11S
2S
)z ,y ,(x s3s3s33S
)z ,y ,(x s4s4s4
iS
4S
)z ,y ,(x s2s2s2
1D
2D3D
4D
iD)z ,y ,(x sisisiPD
(x, y, z)
)z ,y ,(x s1s1s11S
2S
)z ,y ,(x s3s3s33S
)z ,y ,(x s4s4s4
iS
4S
)z ,y ,(x s2s2s2
1D
2D3D
4D
iD)z ,y ,(x sisisiPD
(x, y, z)
)z ,y ,(x s1s1s11S
2S
)z ,y ,(x s3s3s33S
)z ,y ,(x s4s4s4
iS
4S
)z ,y ,(x s2s2s2
1D
2D3D
4D
iD)z ,y ,(x sisisiPD
(x, y, z)
schematic view of a transformer tank with acoustic sensors
( ) ( ) ( ) ( )212
12
12
1 Sssss Tvzzyyxx ⋅=−+−+−
( ) ( ) ( ) ( )222
22
22
2 Sssss Tvzzyyxx ⋅=−+−+−
( ) ( ) ( ) ( )23
23
23
23 Sssss Tvzzyyxx ⋅=−+−+−
( ) ( ) ( ) ( )212
12
12
1 Sssss Tvzzyyxx ⋅=−+−+−
( ) ( ) ( ) ( )222
22
22
2 Sssss Tvzzyyxx ⋅=−+−+−
( ) ( ) ( ) ( )23
23
23
23 Sssss Tvzzyyxx ⋅=−+−+−
Observation equations:
unknowns x, y, z Input parameters:sensor coordinates, sound
velocity, meas. time difference
sensor 1
sensor 2
sensor 3PD
sensor 1
sensor 2
sensor 3PD
triangulation
Advanced tools for PD monitoring Acoustic PD location
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Vibration measurements extended with:sound & AE
High Voltage Side
Side 1L Side1R
Side 2L
Side 2R
Side 3R
Side 4R
Side 3L
Side 4L
0.15@240
0.09@360 0.22ips
0.9ips
0.05ips
Overhead View of Transformer
Snd=80db
AE=35Cts
Snd=78db
AE=30Cts
BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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Major Failure Mechanisms
Aging of paper
Moisture in oil
Looseness –movement of the windings
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Moisture In Oil
Moisture in oil is destructiveto cellulose, especially in thepresence of oxygen.
Presence of moisture willfacilitate partial discharge.
Fiberoptics moisture sensorcan be a part of a CMsolution
BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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Varioussystems
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Dissolved Gas Analysis (DGA)
Power Transformers contain insulating oilWhen a fault occurs, the oil breaks down generating gasThese gases dissolve into the oil Fault type/severity are indicated by gases present
Traditional Methods of DGA1. Samples collected manually from Transformers 2. Analysis performed by specialist oil laboratories3. Sample collection to analysis ranges from days -> weeks 4. Performed on an regular (6 – 12 month) basis
Commonly accepted as the most effective method of Transformer Assessment
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The most important aspects of DGA
• The type of gas created indicates the nature of the fault.
• The rate of increase in these gases indicate the severity of the fault.
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Oil pyrolysis (Thermal Heating)
R eferences:M . Duval, Elect ra,133, 40 (1990 ).T. V. Oommen, Ga s Generat ion in Power T ra nsformers
HYDROGEN H2
METHANE CH4
ETHANE C2 H6
ETHYLENE C2 H4
ACETYLENE C2 H2
GA
S C
ON
STIT
UE
NTS
250 750 1000 1250 1500 1750500Fault Temperature ( °C )
2000
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Cellulose pyrolysis (Thermal Heating)Life of paper ~ Life of transformer
R eferences:M. Duva l, Ele ct ra ,133,40 (1990 ).T. V. Oomm en, Gas Ge ne ra tion in Power Transforme rs
GA
S C
ON
STIT
UEN
TS
200 250 300100 500400
CARBON MONOXIDE CO
CARBON DIOXIDE CO2
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The problem with manual sampling...
A fault can develop and cause failure between samples. A single sample cannot provide rate of change or fault
severity. Human error – sampling & analysis.
These weaknesses are relatively insignificant given:
Transformer catastrophic failure can occur in hours, days or weeks
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Online DGA for a Transformer
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Benefits
Online MonitoringMonitoring unit is connected to TransformerUnit automatically samples oil from TransformerGas extracted from oil, concentration measured Oil sample returned to TransformerProcess repeated
Early fault detection
Defer Capital ExpenditureCondition Based Maintenance
Extend Transformer life
Avoid catastrophic failures
Save Money $$$$
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Examples of Discrete Monitoring Products
TRANSPORT X*• Portable DGA
• 7 fault gases + moisture• Simple & reliable
TRANSFIX*• Full 8 gas +
moisture on-line DGA
MINITRANS*• Cost-Effective on-line DGA• Discrete gas measurement
(H2, CO, C2H2 + H2O)
MULTITRANS*• Full 8 gas multi tank DGA
TAPTRANS*• Full 8 gas on-line DGA for
main tank & LTC in one unit
HYDRAN M2• On-line Integrated Monitor
• Gas & Moisture in oil• On-line Models/Data storage
Intellix MO150 • Low Cost Transformer
Monitoring System
SIGMA TX* (TBC)Comprehensive
transformer monitoring & modelling
• Full 8 Gas DGA • Bushing/PD/Cooling System/FO hot spot*Kelman Products
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Online DGA for a Transformer
an EXAMPLE.....
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Transformer Failure Case StudyNormal DGA
gas levels
Sample Date/Time
Gas
ppm
val
ue
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Transformer Failure Case Study
Sample Date/Time
Gas
ppm
val
ue Gases rise over 3 days as fault occurs – sampling frequency automatically
increases
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Transformer Failure Case Study
Sample Date/Time
Gas
ppm
val
ue
Fault severity high -Transformer removed
from service
Fault occurs rapidly over 8 days –manual sampling would not have
been sufficient to detect
BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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A COMPLEX MONITORING
SYSTEM
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A 300MVA transformer with a DGA systemand a PD On-Line monitoring installed
FARADAY tMEDIC
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Product: System 1 Integrated Substation Purpose: Transformer Monitoring and Diagnostics
Chosen KELMAN products
WAN / LAN
Payoff: Typically 5 to 8 years added life expectancy
HYDRAN FARADAY®, tMEDIC or TMCS™ Units
Process:Monitoring
Modbus Ethernet Scanning Display
Exception Alarm Decision SupportSM
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TRANSFIX• Full 8 gas (+ moisture)
On-Line DGA
SIGMA TX (TBC)Comprehensive transformer
monitoring & modelling• Full 8 Gas (+ moisture)
On-Line DGA • Bushing/PD/Cooling System/FO hot spot
Recommended products for Power Generation Area
At less than 1% of the initial Transformer cost:both solutions provide the vital information
to protect & maximise Power Station critical assets
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Ethernet
System 1
Perception Express
Minitrans DGA Monitor Minitrans DGA Monitor
PT2PT1
Parámetro Rango
Hidrógeno (H2) 5 – 5,000 ppm
Acetileno (C2H2) 0.5 – 50,000 ppm
Monóxido de Carbono (CO) 2 – 50,000 ppm
Agua (H2O) 1-100% de Humedad Relativa
DGA en Transformadores de Poder
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TP1 – 3 x HFCTs ( High Frequency Current Transformers
PDCheck - Techimp
TP2 – 3 x HFCTs ( High Frequency Current Transformers
PDCheck - Techimp
Ethernet
System 1
Descargas Parciales en Transformadores de Poder
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UNIT #3PROTECTION SYSTEM / ESD
{ from BINARY OUTPUTS of the M&PS SYSTEM }
Unit 1
UNIT #1PROTECTION SYSTEM / ESD
{ from BINARY OUTPUTS of the M&PS SYSTEM }
UNIT #2PROTECTION SYSTEM / ESD
{ from BINARY OUTPUTS of the M&PS SYSTEM }
A SERVER OFA HS DIAGNOSTIC SYSTEM:
Unit 2 Unit N...
An example with
TRANSFIX from KELMAN
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BASICS of TRANSFORMER CM
1. Introduction to TRANSFORMER MAINTENANCE
2. TEMPERATURE SENSING
3. VIBRATION MONITORING
4. PARTIAL DISCHARGES (ACOUSTIC EMISSION)
5. MOISTURE MONITORING
6. GAS MONITORING DGA
7. Examples of SYSTEM SOLUTIONS
8. ENDING
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The Cost of Transformer Failure
A study by The Hartford Steam Boiler Inspection and Insurance Company (HSB)
estimates the cost of Transformer failure at approx
$10,000 per MVA
HSB has been founded in 1866
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The Cost of Transformer Failure
A study by The Hartford Steam Boiler Inspection and Insurance Company (HSB)
estimates the cost of Transformer failure at approx
$10,000 per MVA
HSB has been founded in 1866
COST OF PREVENTIONOnline DGA monitoring can cost less
than 1% of the initial Transformer Cost
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Transformer Life Management
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Questions