Post on 17-Jul-2016
description
During a transformer short circuit, the TRANSFORMER PROTECTOR is activated within milliseconds by the first
dynamic pressure of the shock wave, avoiding transformer explosions before static pressure increase
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
www.sergi-france.com
TRANSFORMER PROTECTOR Presentation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 2
NFPA
The TRANSFORMER PROTECTOR is now recommended for all Power Plants and Substations in the National Fire Protection Association 2010 edition of:
• NFPA 850 (Recommended Practice for Fire Protection for Electric Generating Plants and High Voltage Direct Current Converter Stations),
• NFPA 851 (Recommended Practice for Fire Protection for Hydroelectric Generating Plants).
The introduction of the 2010 edition of NFPA 850 & NFPA 851 stands :“Fast depressurisation systems have been recognized, and
recommendations for the use of these systems are now included”
“Fast depressurisation system: a passive mechanical system designed to depressurizethe transformer a few milliseconds after the occurrence of an electrical fault”
More details later in the presentation or
Just click here
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
• Why do transformers explode ? • TP strategy
• Examples of explosions • Conventional protections • The answer
• Experimental tests• Physical phenomena
• Standard configuration• The TP components
• NFPA, FM Global, IEEE…• World references
3
Overview of the presentation
2. The TP principle to prevent transformer explosion
3. Physical explanations
4. TP technical description
5. References
• Retrofitting• TP order process
• Successful activations• Examples of installations
• Simulations (model, application 200 MVA)• Real case study (400 MVA)
• Other configurations• TP options
• Detailed TP operation
1. Transformers are very dangerous
Conclusion
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
• Why do transformers explode ? • TP strategy
• Examples of explosions • Conventional protections • The answer
• Experimental tests• Physical phenomena
• Standard configuration• The TP components
• NFPA, FM Global, IEEE…• World references
4
Overview of the presentation
2. The TP principle to prevent transformer explosion
3. Physical explanations
4. TP technical description
5. References
• Retrofitting• TP order process
• Successful activations• Examples of installations
• Simulations (model, application 200 MVA)• Real case study (400 MVA)
• Other configurations• TP options
• Detailed TP operation
1. Transformers are very dangerous
Conclusion
From this “overview” page, you can navigate through the complete presentation by clicking
on the item you want to see
Click here if you want to see the “detailed TP operation”
Just click on the SERGI logo to go back to the “overview page”
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
• Why do transformers explode ? • TP strategy
• Examples of explosions • Conventional protections • The answer
• Experimental tests• Physical phenomena
• Standard configuration• The TP components
• NFPA, FM Global, IEEE…• World references
5
Overview of the presentation
2. The TP principle to prevent transformer explosion
3. Physical explanations
4. TP technical description
5. References
• Retrofitting• TP order process
• Successful activations• Examples of installations
• Simulations (model, application 200 MVA)• Real case study (400 MVA)
• Other configurations• TP options
• Detailed TP operation
1. Transformers are very dangerous
Conclusion
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 6
1. Transformers are very dangerous
• Examples of explosions
• Conventional protections
• The answer
1. Transformers are very dangerous
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 7
Danger :
• The whole power plant (1,350MW)was out of service for 4 months.
• The damaged section (450 MW)was out of service for 13 months.
• 2 people were badly burned.
• Fire extinguishing systems did not work.
• Security fire doors were too slow.
Power transformers are very dangerous
Transformer explosion in a power plant
• Large quantity of oil in contact with high voltage elements
• No international security norm for transformers
1. Transformers are very dangerousExamples of explosions
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 8
Ottawa Hydro, Canada, March 2009
transformer burned during hours
Other explosion examplesTransformer explosions lead to: 2
• Huge fire
• Plant outage
• Huge costs :
hundreds millions Euros
• Ruin company reputation
• Environmental pollution
• Human life risks
1. Transformers are very dangerous Examples of explosions
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 9
Other explosion examples
Krümmel Nuclear Power Plant, Germany
June 2007, still not restarted !
Cost: 1 Million Euros / day !
3Transformer explosions lead to:
• Huge fire
• Plant outage
• Huge costs :
hundreds millions Euros
• Ruin company reputation
• Environmental pollution
• Human life risks
1. Transformers are very dangerous Examples of explosions
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 10
Blénod Coal Power Plant, EDF, France
May 2009
Other explosion examples 4
1. Transformers are very dangerous Examples of explosions
Transformer explosions lead to:
• Huge fire
• Plant outage
• Huge costs :
hundreds millions Euros
• Ruin company reputation
• Environmental pollution
• Human life risks
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 11
1. Transformers are very dangerous Conventional protections
a) South Band, Illinois , USA, 1999
Efficiency ?Corrective Means
• Firewalls • Fire extinguishing systems
Limit fire propagation
induced by the explosion Fire propagated from one transformer to the other
1
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 12
1. Transformers are very dangerous Conventional protections
b) Venice Plant, Illinois , USA, 2000
Efficiency ?Corrective Means
Solution : Preventing transformer explosion to avoid fire
• Firewalls • Fire extinguishing systems
Limit fire propagation
induced by the explosion
Fire propagated to the whole plant: All 9 transformers caught fire despite
fire walls and fire extinguishing systems (cost: USD 230 millions)
1
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 13
1. Transformers are very dangerous Conventional protections
All explodedtransformers
were equippedwith these
devices
Efficiency ?Preventive Means
• Circuit breakers
• Buchholz Relay
• Sudden Pressure Relay
• Gas Monitoring
• Pressure Relieve Valve
Solution : The protection must act faster !
2
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 14
1. Transformers are very dangerous The answer
During a short circuit, the TP isactivated within milliseconds bythe first dynamic pressure peak ofthe shock wave, avoidingexplosions by preventing staticpressure increase.
The TP key of success
The TRANSFORMER PROTECTOR (TP)
The TP depressurizes transformers within milliseconds avoiding explosion and subsequent fire.
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 15
2. Preventing transformer explosion: the TP Principle
• Transformer explosion process
• TP strategy to prevent explosion
• TP operation
• TP standard configuration
• TP operation movie
2. Preventing Transformer Explosion:
The TP Principle
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 16
Why do transformers explode ?
Dielectric oil insulation rupture
Electrical arc
Oil vaporization
Local dynamic pressure increase
First dynamic pressure peak propagates
Dynamic pressure peak reflects off walls
Static pressure increases
Tank rupture & Fire
2. Preventing transformer explosion: the TP principle Transformer explosion process
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 17
How to break that sequence?
Dielectric oil insulation rupture
Electrical arc
Oil vaporization
Local dynamic pressure increase
First dynamic pressure peak propagates
Dynamic pressure peak reflects off walls
Static pressure increases
Tank rupture & Fire
2. Preventing transformer explosion: the TP principle Prevention strategy
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 18
Activation within milliseconds by the first dynamic pressure peak
Quick Oil Evacuation
Tank depressurization
Prevents the explosion
How to break that sequence?
Dielectric oil insulation rupture
Electrical arc
Oil vaporization
Local dynamic pressure increase
First dynamic pressure peak propagates
Dynamic pressure peak reflects off walls
2. Preventing transformer explosion: the TP principle Prevention strategy
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 19
2. Preventing transformer explosion: the TP principle TP operation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 20
2. Preventing transformer explosion: the TP principle TP operation
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 21
2. Preventing transformer explosion: the TP principle TP operation
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 22
2. Preventing transformer explosion: the TP principle TP operation
• Explosive gases remain
• Melting parts of the windings arestill emitting gases
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 23
2. Preventing transformer explosion: the TP principle TP operation
Evacuation of the explosive gases until the melted parts are cooled down (~ 45 mn)
Injection of Inert Gas2
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
• Explosive gases remain
• Melting parts of the windings arestill emitting gases
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 24
2. Preventing transformer explosion: the TP principle TP operation
Transformer safe and ready for repair
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
Evacuation of the explosive gases until the melted parts are cooled down (~ 45 mn)
Injection of Inert Gas2
• Explosive gases remain
• Melting parts of the windings arestill emitting gases
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 25
2. Preventing transformer explosion: the TP principle TP standard configuration
Standard TRANSFORMER PROTECTOR (TP)
6
2
14
1. Vertical Depressurization Set (VDS)
2. OLTC Depressurization Set (OLTC DS)
3. Slice Oil-Gas Separation Tank (SOGST)
4. Explosive Gases Evacuation Pipe (EGEP)
5. Air Isolation Shutter
6. TP Cabinet
7. Inert Gas Injection Pipe (IGIP)
The ComponentsTP Components
7
3
5
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 26
• General overview of the experimental tests
• Exhibited physical phenomena:
Oil vaporization
Dynamic pressure peak propagation
Tank can withstand high dynamic pressure peak
Tank rupture because of static pressure increase
TP reaction to the phenomena
• Simulations:
Quick presentation of the simulation tool
Comparison with / without TP
Real case study – 400 MVA explosion prevention
• Tank design using ASME standards
3. Physical Explanations
3. Physical Explanations
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 27
3. Physical Explanations Experimental tests: general overview
• 2002: 28 tests by EDF (Electricitéde France) on small transformers
Two main test campaigns
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 28
Two main test campaigns
• 2002: 28 tests by EDF (Electricitéde France) on small transformers
• 2004: 34 tests by CEPEL (HVindependent lab.) on largetransformers (8.4m – 26ft)
3. Physical Explanations Experimental tests: general overview
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 29
3. Physical Explanations Experimental tests: general overview
Two main test campaigns
Conclusion
During the 62 tests, the TP always saved transformers from explosion without permanent tank deformation
• 2002: 28 tests by EDF (Electricitéde France) on small transformers
• 2004: 34 tests by CEPEL (HVindependent lab.) on largetransformers (8.4m – 26ft)
• Principle: electrical arcs wereignited inside transformers tanksequipped with a TP
Click on pictures to watch videos
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 30
• General overview of the experimental tests
• Exhibited physical phenomena:
Oil vaporization & gas creation
Dynamic pressure peak propagation
Tank can withstand high dynamic pressure peak
Tank rupture because of static pressure increase
TP reaction to the physical phenomena
• Simulations:
Quick presentation of the simulation tool
Comparison with / without TP
Real case study – 400 MVA explosion prevention
• Tank reinforcements influence using ASME standards
3. Physical Explanations
3. Physical Explanations
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 31
3. Physical Explanations Vaporization saturation process
SKIP
1st key phenomena: oil vaporization & arc creation – video1
Arc movie during the EDF testsHigh speed camera 3000 fps
Chronology
0 ms : Start of applied current
3.66 ms : Bubble generation
4 ms : Bubble volume = 9 cm3, 0.5 in.3
4.33 ms : Bubble volume = 60 cm3, 3.7 in.3
4.66 ms : Bubble volume = 97 cm3, 5.9 in.3
5 ms : Bubble volume = 190 cm3, 11.6 in.3
5.33 ms : Bubble volume = 299 cm3, 18.2 in.3
5.66 ms : Bubble volume = 399 cm3, 24.3 in.3
6 ms : Bubble volume = 568 cm3, 34.7 in.3
6.33 ms : Electrical arc fully developed - plasma
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 32
3. Physical Explanations and Testing of the TP Vaporization saturation process
SKIP
1st key phenomena: oil vaporization & arc creation – video1
Electrical Arc Produced Gas
Plasma Mineral Oil
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 33
3. Physical Explanations Vaporization saturation process
1
VaporizationHeat transfer to the oil
(Joule effect)
Gas bubble – oil vapor
Cracking oil vapor into smaller molecules
Electrical arc fully developed – Plasma
Gas bubble gases with low resistivity
Short circuit Electrical current between 2 points
of the transformer
Less resistivity = more current
Transformer Oil
1st key phenomena: oil vaporization & arc creation – description
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 34
3. Physical Explanations Vaporization saturation process
SKIP
1
a) Flammable and explosive gases are created:
• Acetylene (C2H2), Ethylene (C2H4), Methane (CH4), Hydrogen….
• These gases ignite when exposed to Oxygen
• Example:
• An 0.8 Mega Joule electrical arc occurred in one transformer.
• 1.8 m3 (62.4ft 3) of gas was created, exploded the tank, escaped & ignited
• The fire ball propagates in the whole section looking for oxygen and destroys everything on its path.
• The section (450 MVA) was out of service for 13 months!
1st key phenomena: oil vaporization & arc creation – analyse
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
1st step:
Arc in contact with oil
Enormous Vaporization
b) Measurements
Transformer Oil
• When the arc occurs, direct contact between arc and liquid oil
• High energy exchange to liquid oil
Fast & huge vaporization
35
HEAT EXCHANGEARC TO OIL
HEAT EXCHANGEARC TO OIL
HEAT EXCHANGEARC TO OIL
3. Physical Explanations Vaporization saturation process
1
c) Physical explanation: 1st step
Arc Energy (in MJ)
1st step: the 1st Mega Joule produces 2.3 m3 – 81 ft3 of explosive gas
Gen
erat
ed G
as V
olu
me
(in
m3)
Gas
1st key phenomena: oil vaporization & arc creation – analyse
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
b) Measurements
• Arc surrounded by gas
• Gas heated by the arc (~2000 C) and then ionized, creating plasma
• Less energy transfer to liquid oil
Much slower vaporization
36
3. Physical Explanations Vaporization saturation process
1
c) Physical explanation: 2nd step
1st step: the 1st Mega Joule produces 2.3 m3 – 81 ft3 of explosive gas
Arc Energy (in MJ)
2nd step: the following 19 MJ produce only 1.2 m3 – 42 ft3 of gas
3) CREATION OF PLASMA
1) HEATING THE
GAS
Transformer OilGen
erat
ed G
as V
olu
me
(in
m3)
Gas
2) IONISATION
1st key phenomena: oil vaporization & arc creation – analyse
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
b) Measurements
37
3. Physical Explanations Vaporization saturation process
1
Arc Energy (in MJ)Gen
erat
ed G
as V
olu
me
(in
m3)
The oil vaporization occurs in the first milliseconds and stabilizes when the electrical arc is surrounded by gas
Vaporisation Saturation
Transformer Oil
Gas
c) Physical explanation: 2nd step
3) CREATION OF PLASMA
1) HEATING THE
GAS
2) IONISATION
1st key phenomena: oil vaporization & arc creation – analyse
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 38
3. Physical Explanations Pressure increase in the gas bubble
2nd key phenomena: quick pressure increase in gas bubble
1
2
Transformer Oil
Gas density is ~1000 times less than liquid density
The gas bubble wants to expend
But liquid oil inertia avoids the bubble expansion
Fast pressure increase in the gas bubble
(up to 5000 bar/s – 75000 psi/s)
1st key phenomena: oil vaporization & arc creation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Maximum pressure peak amplitude recorded for each test (gauge pressure):
Only a moderate influence of the arc energy to the bubble pressure
39
2nd key phenomena: quick pressure increase in gas bubble
1st key phenomena: oil vaporization & arc creation1
2
+9 bar (130 psi)
1 MJ
+3 bar (40 psi)
1 MJ
+13 bar (190 psi)
2.5 MJ
+10.5 bar (150 psi)
125 kJ
3. Physical Explanations Pressure increase in the gas bubble
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 40
2nd key phenomena: quick pressure increase in gas bubble
1st key phenomena: oil vaporization & arc creation1
2
• Vaporization saturation process
• Only a moderate influence of the arc energy to the pressure peak amplitude
Arc energy and transformer power rating are not the critical factors for transformer explosion!
3. Physical Explanations Pressure increase in the gas bubble
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 41
2nd key phenomena: quick pressure increase in the gas bubble
1st key phenomena: oil vaporization & arc creation1
3rd key phenomena: the dynamic pressure peak propagates3
2
Transformer
Oil
3. Physical Explanations Dynamic pressure propagation
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 42
3. Physical Explanations Dynamic pressure propagation
Gauge pressure evolution measured at different locations
• Overpressure generated by the arc is not uniform in the tank• The pressure peak propagates at the speed of sound in the oil
1200 m/s ie 4000 ft/s• Secondary peaks are due to reflections of the first peak off the walls
Dynamic
Pressure
Close to the arc (C)
At the tank cover (B)
Close to the TP (A)
A
B
C
TP
3rd key phenomena: the dynamic pressure peak propagates3
arc
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 43
3. Physical Explanations Tank withstand to dynamic pressure
2nd key phenomena: quick pressure increase in the gas bubble
1st key phenomena: oil vaporization & arc creation1
3rd key phenomena: the dynamic pressure peak propagates3
2
4th key phenomena: tank can withstand high dynamic pressure peaks4
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 44
3. Physical Explanations Tank withstand to dynamic pressure
Maximum dynamic pressure peak amplitude recorded for each test (gauge pressure):
Tank can withstand dynamic pressure peaks up to +13 bar – 190 psi (gauge)
4th key phenomena: tank can withstand high dynamic pressure peaks4
+13 bar (190 psi)
+10.5 bar (150 psi)
+11 bar (160 psi)
No Rupture !
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Dynamic Pressure
• Very localized and moving in the tank
• Propagates very quickly within the tank (1200 m/s – 4000 ft/s)
45
3. Physical Explanations Tank withstand to dynamic pressure
4th key phenomena: tank can withstand high dynamic pressure peaks4
Physical explanation:
No rupture induced by dynamic pressure!
Tank withstand capabilities
• Tank welding and bolts have a longinertia to break
• Dynamic pressure peak is travelingvery fast: welding and bolts haveno time to integrate the pressure.
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 46
3. Physical Explanations Tank ruptures due to static pressure
2nd key phenomena: quick pressure increase in the gas bubble
1st key phenomena: oil vaporization & arc creation1
3rd key phenomena: the dynamic pressure peak propagates3
2
4th key phenomena: tank can withstand high dynamic pressure peaks4
5th key phenomena: tanks rupture because of static pressure5
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 47
3. Physical Explanations Tank ruptures due to static pressure
Tanks rupture because of static pressure
5th key phenomena: tanks rupture because of static pressure5
• Static Pressure: uniform and progressive pressure increase all over the tank
• Slow phenomena for which oil reacts like incompressible media
• Tank maximum static withstand limit: between 0.7 and 1.2 bar (gauge).
pressure gradients less than 25 bar/s – 350 psi/s
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 48
3. Physical ExplanationsDynamic / static pressure
• Spatially uniform all over the tank
• Progressive, slow increase
• Oil behaves as an incompressible media
• Max withstand ~1 bar – 15 psi (gauge)
• Very localized and moving in the tank
• Propagates quickly within the tank
• Oil behaves as a compressible media
• Tank can resist 13 bar – 190 psi (gauge)
The tank does not explode The tank explodes
Dynamic PressurePressure gradients over 25 bar/s – 360 psi/s
Static PressurePressure gradients under 25 bar/s – 360 psi/s
Pressure gradients up to 5000 bar/s – 72000 psi/s
Propagation speed: 1200 m/s – 4000 ft/s
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 49
3. Physical Explanations Dynamic / static pressure
How does Dynamic Pressure become Static Pressure ?
The dynamic pressure peak travels and reflects off
the walls, creates secondary peaks building slowly
static pressure.
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 50
3. Physical Explanations Dynamic / static pressure
How does Dynamic Pressure become Static Pressure ?
Evolution of the pressure at different sensors in the tank:
Simulation parameters
• No TP installed on the transformer
• Supposing the tank does not
explode
• 5.6 m – 19 ft long transformer
• 0.5 MJ fault generating 1.5 m3 –
50 ft 3 of gas.
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 51
3. Physical Explanations Dynamic / static pressure
How does Dynamic Pressure become Static Pressure ?
Evolution of the pressure at different sensors in the tank:
TP Strategy
To prevent Dynamic Pressure from becoming Static Pressure
1. The arc generates one high
pressure peak
2. This dynamic pressure peak
propagates in the tank
3. Reflects off the wall and
creates secondary peaks
4. Static pressure is built up
after only 100 ms
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 52
3. Physical Explanations Influence of the TP
2nd key phenomena: quick pressure increase in the gas bubble
1st key phenomena: oil vaporization & arc creation1
3rd key phenomena: the dynamic pressure peak propagates3
2
4th key phenomena: tank can withstand high dynamic pressure peaks4
5th key phenomena: tank ruptures because of static pressure5
6th key phenomena: the TP depressurizes tanks preventing explosion6
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 53
3. Physical Explanations Influence of the TP
6th key phenomena: the TP depressurizes tanks preventing explosion6
Depressurization SetTraveling distance : 8,5 m – 26 ft
Electrical Arc at the opposite side of the TP
Windings
Dynamic pressure sensor located close to the TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 54
3. Physical Explanations Influence of the TP
The TP is activated in 8 ms,
time for the dynamic
pressure peak generated by
the arc to reach the sensor:
8.5 m at 1200 m/s
(26 ft at 4000 ft/s)
Dynamic pressure recorded close to the depressurization set
8 ms
The TP depressurizes the tank in milliseconds, even if the arc is
fed for a longer period
6th key phenomena: the TP depressurizes tanks preventing explosion6
58000 psi/s
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 55
The TP depressurizes the tank in milliseconds, even if the arc is
fed for a longer period
3. Physical Explanations Influence of the TP
No static pressure
No tank rupture
Dynamic pressure recorded close to the depressurization set
6th key phenomena: the TP depressurizes tanks preventing explosion6
58000 psi/s
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 56
3. Physical Explanations Influence of the TP
a) No static pressure
The quick oil evacuation generates
rarefaction waves that
depressurizes the tank
before static pressure builds up. 0 ~10 ms
Arc occurrence
TP is activated
Tank is depressurized
~80 ms
Dyn. pressure travelling
Oil evacuation
6th key phenomena: the TP depressurizes tanks preventing explosion6
b) No explosive gases ignition
The gases created by the arc are:
• cooled down
• diluted with inert gases
• evacuated to a remote area
The TP prevents transformer
explosions & fires
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 57
Recapitulation of the main physical phenomena
1. The vaporization saturation
2. The dynamic pressure propagates
3. Tank can withstand high dynamic pressure peaks
4. Tanks rupture because of static pressure
5. The TP induces a fast depressurization preventing the tank explosion
Dynamic pressure peakpropagation
(up to 13 bar – 190 psi)
3. Physical Explanations TP key of success
Recapitulation of the main physical phenomena
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 58
3. Physical Explanations TP key of success
During a short circuit, the TP is activated withinmilliseconds by the first dynamic pressure peakof the shock wave, avoiding explosions bypreventing static pressure increase.
TRANSFORMER PROTECTOR key of success
Recapitulation of the main physical phenomena
1. The vaporization saturation
2. The dynamic pressure propagates
3. Tank can withstand high dynamic pressure peaks
4. Tanks rupture because of static pressure
5. The TP induces a fast depressurization preventing the tank explosion
Recapitulation of the main physical phenomena
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 59
• General overview of the experimental tests
• Exhibited physical phenomena:
Oil vaporization
Dynamic pressure peak propagation
Tank can withstand high dynamic pressure peak
Tank rupture because of static pressure increase
TP reaction to the physical phenomena
• Simulations:
Quick presentation of the simulation tool
Comparison with / without TP
Real case study – 400 MVA explosion prevention
• Tank reinforcements influence using ASME standards
3. Physical Explanations
3. Physical Explanations
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 60
3. Physical Explanations Simulation tool – Presentation
During the 62 tests, electrical arcs were always ignited inside closed
transformers tanks equipped with TP
The TP always saved transformers without permanent tank deformation
What would happen without TP ? Explosion: too dangerous to test
What would happen in other configurations ? Too costly to test
Using computer simulations is an alternative
SERGI has developed its own simulation tool:
Simulate gas and liquid
Pressure propagation
Complex 3D geometries
Leads to various scientific publications (2008 PowerGen Conference Best
Paper Award, IEEE, Cigre and ASME Conferences…)
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 61
0 mst =
11 MJ electrical arc
3. Physical Explanations Simulation tool – 200 MVA transformer – no protection
SKIP
Application 1: 200 MVA Transformer
(5.75m x 3.25m x 2.5m) – (19ft x 11ft x 8ft)
Pressure (gauge)
(psi) (bar)
without TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
1 ms
62
1 mst =Gas bubble under pressure
3. Physical Explanations Simulation tool – 200 MVA transformer – no protection
11 MJ electrical arc
Pressure (gauge)
(psi) (bar)
without TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
4 ms
1 ms
63
3 ms2 ms4 mst =Gas bubble under pressure
The first dynamic pressure peak
propagates
3. Physical ExplanationsSimulation tool – 200 MVA transformer – no protection
11 MJ electrical arc
Pressure (gauge)
(psi) (bar)
without TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
10 ms
4 ms
1 ms
64
5 ms6 ms7 ms8 ms9 mst =
Reflects off the walls and creates
complex pressure waves
Gas bubble under pressure
The first dynamic pressure peak
propagates
10 ms
3. Physical Explanations Simulation tool – 200 MVA transformer – no protection
11 MJ electrical arc
Pressure (gauge)
(psi) (bar)
without TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
30 ms
10 ms
4 ms
1 ms
65
11 ms12 ms13 ms15 ms14 ms16 ms17 ms19 ms18 ms22 ms24 ms20 ms25 mst =
Dynamic pressure reach more than
9 bar – 130 psi (gauge) in a bushing
Reflects off the walls and creates
complex pressure waves
Gas bubble under pressure
The first dynamic pressure peak
propagates
30 ms
3. Physical Explanations Simulation tool – 200 MVA transformer – no protection
11 MJ electrical arc
Pressure (gauge)
(psi) (bar)
without TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
50 ms
30 ms
10 ms
4 ms
1 ms
66
38 ms35 ms40 ms45 mst =
Static pressure builds up
Dynamic pressure reach more than
9 bar – 130 psi (gauge) in a bushing
Reflects off the walls and creates
complex pressure waves
11 MJ electrical arc
Gas bubble under pressure
The first dynamic pressure peak
propagates
50 ms
3. Physical Explanations Simulation tool – 200 MVA transformer – no protection
without TP
Pressure (gauge)
(psi) (bar)
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
50 ms
30 ms
10 ms
4 ms
1 ms
100 ms
67
50 ms60 ms70 ms80 mst =
Static pressure builds up
Dynamic pressure reach more than
9 bar – 130 psi (gauge) in a bushing
Reflects off the walls and creates
complex pressure waves
Gas bubble under pressure
The first dynamic pressure peak
propagates
Static pressure stabilizes at
5.5 bar – 80 psi (gauge)
100 ms
Transformer explodes
3. Physical Explanations Simulation tool – 200 MVA transformer – no protection
11 MJ electrical arc
Max. static withstand limit pressure of
transformer tanks :
1.2 bar – 17 psi (gauge)
Pressure (gauge)
(psi) (bar)
without TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Pressure (gauge)
(psi) (bar)
68
0 mst =
without TP
SKIP
3. Physical Explanations Simulation tool – 200 MVA transformer – with TP
with TP
without TP
with TP
11 MJ electrical arc
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Pressure (gauge)
(psi) (bar)
69
1 mst =
3. Physical Explanations Simulation tool – 200 MVA transformer – with TP
11 MJ electrical arc
1 ms Gas bubble under pressure
without TP
with TP
without TP
with TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Pressure (gauge)
(psi) (bar)
70
3 ms2 mst = 4 ms
3. Physical Explanations Simulation tool – 200 MVA transformer – with TP
11 MJ electrical arc
1 ms
4 ms The first dynamic pressure peak propagates
Gas bubble under pressure
without TP
with TP
without TP
with TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Pressure (gauge)
(psi) (bar)
71
5 ms6 ms7 ms8 ms9 mst =10 ms
3. Physical Explanations Simulation tool – 200 MVA transformer – with TP
11 MJ electrical arc
1 ms
4 ms
10 ms The dynamic pressure peak activates the TP
Gas bubble under pressure
The first dynamic pressure peak propagates
without TP
with TP
without TP
with TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Pressure (gauge)
(psi) (bar)
72
14 ms11 ms12 ms13 mst =15 ms
3. Physical Explanations Simulation tool – 200 MVA transformer – with TP
11 MJ electrical arc
1 ms
4 ms
10 ms
15 ms Rarefaction waves are spread in the tank
The dynamic pressure peak activates the TP
Gas bubble under pressure
The first dynamic pressure peak propagates
without TP
with TP
without TP
with TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Pressure (gauge)
(psi) (bar)
73
16 ms17 ms19 ms18 ms22 ms24 mst =20 ms25 ms30 ms
3. Physical Explanations Simulation tool – 200 MVA transformer – with TP
11 MJ electrical arc
1 ms
4 ms
10 ms
15 ms
30 ms The tank depressurizes
Rarefaction waves are spread in the tank
The dynamic pressure peak activates the TP
Gas bubble under pressure
The first dynamic pressure peak propagates
without TP
with TP
without TP
with TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Pressure (gauge)
(psi) (bar)
74
35 ms40 ms45 ms50 mst =60 ms
3. Physical ExplanationsSimulation tool – 200 MVA transformer – with TP
11 MJ electrical arc
1 ms
4 ms
10 ms
15 ms
30 ms
60 ms The tank is fully depressurized
The tank depressurizes
Rarefaction waves are spread in the tank
The dynamic pressure peak activates the TP
Gas bubble under pressure
The first dynamic pressure peak propagates
without TP
with TP
without TP
with TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
1 ms
75
70 ms80 ms100 mst =
After 60 ms
11 MJ electrical arc
Gas bubble under pressure
150 ms
3. Physical ExplanationsSimulation tool – 200 MVA transformer – with TP
4 ms
10 ms The dynamic pressure peak activates the TP
The first dynamic pressure peak propagates
15 ms
30 ms
60 ms
The tank depressurizes
Rarefaction waves are spread in the tank
The tank is fully depressurized
without TP
with TP
• without TP, static press. = 5.5 bar – 80 psi
Pressure (gauge)
(psi) (bar)
• with TP, static pressure = atm. pressure
without TP
with TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 76
Application 2: Real case study – 400 MVA Transformer Explosion
Electrical Fault :
80kA, 110ms, 11 MJ
Two plates on bushing
turrets exploded
The first one was ejected
30 meters – 100 feet away !
What is the result of the simulations ?
Dimensions: 7.8 m x 3.2 m x 4 m
26 ft x 10 ft x 13 ft
SKIP
3. Physical Explanations Simulation tool – Real case study – 400 MVA transformer
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
after 120 ms
77
3. Physical Explanations Simulation tool – Real case study – 400 MVA transformer
• Without TP, the max. pressure is 14 bar – 200 psi and the static pressure builds up at around 7 bar – 100 psi.
the tank explodes
• With TP, the first dynamic pressure peak activated the TP within milliseconds before static pressure is built up.
the tank is safe
with TPwithout TP
Pressure (gauge)(psi) (bar)
after 120 ms after 120 ms
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 78
3. Physical Explanations Tank reinforcement
• ASME (American Society of Mechanical Engineers) establishes tank design rules.
• On the previous examples, simulations show static overpressure stabilizes around 7 bar – 100 psi gauge (10 times more than usual static overpressure limit).
• ASME Standard gives the minimum thickness of a tank t to withstand an internal overpressure Pi :
ij
i
PSE
RPt
2.02
S : Maximum allowable stress value
R : radius of the shell
Ej : Efficiency of the jointsNegligible for transformer structures
Linear relation between the min. thickness and the internal overpressure
= k Pi
Computation of the tank thickness using ASME standards
(Extract from “Prevention of transformer tank explosion, Part 3: Design of efficient protections using simulations”, ASME PVP Conference Proceedings, 2009, available on request)
To withstand overpressures generated by an electrical arc, tanks should be 10 times thicker than usual !
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 79
3. Physical Explanations Tank reinforcement
• ASME (American Society of Mechanical Engineers) establishes tank design rules.
• On the previous examples, simulations show static overpressure stabilizes around 7 bar – 100 psi gauge (10 times more than usual static overpressure limit).
• ASME Standard gives the minimum thickness of a tank t to withstand an internal overpressure Pi :
ij
i
PSE
RPt
2.02
S : Maximum allowable stress value
R : radius of the shell
Ej : Efficiency of the jointsNegligible for transformer structures
Linear relation between the min. thickness and the internal overpressure
= k Pi
Computation of the tank thickness using ASME standards
(Extract from “Prevention of transformer tank explosion, Part 3: Design of efficient protections using simulations”, ASME PVP Conference Proceedings, 2009, available on request)
Trying to reinforce the tank structure is therefore irrelevant
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 80
• TP standard configuration
• Detailed TP components description
• Other TP configurations
• Retrofitting
• TP options
• TP order process
4. TP Technical Description
4. TP Technical Description
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 81
4. TP Technical Description TP standard configuration
Standard TRANSFORMER PROTECTOR (TP)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 82
Reminder of the TP Principle
4. TP Technical Description TP Principle
SKIP
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 83
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
4. TP Technical Description TP Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 84
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
4. TP Technical Description TP Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 85
• Explosive gases remain
• Melting parts of the windings arestill emitting gases
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
4. TP Technical Description TP Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 86
Evacuation of the explosive gases until the melted parts are cooled down (~ 45 mn)
Injection of Inert Gas2
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
• Explosive gases remain
• Melting parts of the windings arestill emitting gases
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
4. TP Technical Description TP Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 87
Transformer safe and ready for repair
Quick oil evacuation generating fast depressurization of the tank (within milliseconds)
TP Activation1
Evacuation of the explosive gases until the melted parts are cooled down (~ 45 mn)
Injection of Inert Gas2
• Explosive gases remain
• Melting parts of the windings arestill emitting gases
• Electrical arc
• Pressurized gas bubble
• Dynamic pressure peak propagation
4. TP Technical Description TP Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 88
4. TP Technical Description TP standard configuration
Standard TRANSFORMER PROTECTOR (TP)
6
2
14
1. Vertical Depressurization Set (VDS)
2. OLTC Depressurization Set (OLTC DS)
3. Slice Oil-Gas Separation Tank (SOGST)
4. Explosive Gases Evacuation Pipe (EGEP)
5. Air Isolation Shutter
6. TP Cabinet
7. Inert Gas Injection Pipe (IGIP)
The ComponentsTP Components
7
3
5
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
TP Components
89
4. TP Technical Description Standard TP components: Vertical Depressurization Set (VDS)
SKIP
Standard TRANSFORMER PROTECTOR (TP)
1. Vertical Depressurization Set (VDS)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 90
4. TP Technical Description Standard TP components: Vertical Depressurization Set (VDS)
Vertical Depressurization Set (VDS)
Principle
• to relieve overpressure and to favor
high-speed depressurization
• diameter is calculated individually
for each transformer types
• includes an Isolation Valve (IV), a
Shock Absorber (SA) and a Vibration
Absorber (VA)
Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 91
4. TP Technical Description Standard TP components: Vertical Depressurization Set (VDS)
Vertical Depressurization Set (VDS)
Elements
1. Transformer Interface (TI)
2. Isolation Valve (IV)
3. Shock Absorber (SA)
4. Rupture Disk (RD)
5. Vibration Absorber (VA)
6. Decompression Chamber (DC)
7. Oil Outlet
8. Gases Outlet
Elements
1
2
3
4
5
6
7
8
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 92
4. TP Technical Description Standard TP components: OLTC Depressurization Set (OLTC DS)
Standard TRANSFORMER PROTECTOR (TP)
The ComponentsTP Components
1. Vertical Depressurization Set (VDS)
2. OLTC Depressurization Set (OLTC DS)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 93
4. TP Technical Description Standard TP components: OLTC Depressurization Set (OLTC DS)
OLTC Depressurization Set (OLTC DS)
1
23
1. Rupture Disk with integrated Burst Indicator (RD BI)
2. Decompression Chamber (DC)
3. Explosive Gas Elimination Pipe (EGEP)
Elements
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 94
4. TP Technical Description Standard TP components: Slice Oil-Gas Separation Tank (SOGST)
Standard TRANSFORMER PROTECTOR (TP)
The ComponentsTP Components
1. Vertical Depressurization Set (VDS)
2. OLTC Depressurization Set (OLTC DS)
3. Slice Oil-Gas Separation Tank (SOGST)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 95
4. TP Technical Description Standard TP components: Slice Oil-Gas Separation Tank (SOGST)
Slice Oil-Gas Separation Tank (SOGST)
Principle
• The OGST collects the depressurized oil and flammable gas mixture
• Then, the OGST separates gases from oil and the gases are channeled away to a remote area
Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 96
Slice Oil-Gas Separation Tank (SOGST)
14
6
253
4. TP Technical Description Standard TP components: Slice Oil-Gas Separation Tank (SOGST)
Elements
1. Main Conservator Compartment connected to Transformer Tank
2. Conservator Pipe to BuchholtzRelay and Transformer Tank
3. Partition Barrier
4. Slice OGST (SOGST)5. Oil Drain Pipe (ODP) connection
flange from 6 inch to 12 inch6. Explosive Gas Evacuation Pipe
(EGEP) connections 2 inch
Elements
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 97
4. TP Technical Description Standard TP components: Explosive Gas Elimination Set (EGES)
Standard TRANSFORMER PROTECTOR (TP)
The ComponentsTP Components
1. Vertical Depressurization Set
2. OLTC Depressurization Set
3. Slice Oil - Gas Separation Tank
4. Explosive Gases Evacuation Pipe (EGEP)
5. TP Cabinet
6. Inert Gas Injection Pipes (IGIP)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Explosive Gas Elimination Set: the TP Cabinet
98
Elements
1. Inert Gas Cylinder (IGC)2. Manometer3. Pressure Reducer (PR)4. Pipe to transformer main
tank5. Pipe to OLTC6. Cabinet Heater (CH)7. In / out of service and
maintenance lights
2
4. TP Technical Description Standard TP components: Explosive Gas Elimination Set (EGES)
SERGI
1
3
7
Elements
4 5
6
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 99
Conventional Control Box (CCB)
4. TP Technical Description Standard TP components: Control Box (CB)
• located in the Control Room
• ensures the logic of the system
• connected to Linear Heat Detectors (LHD), Isolation Valve (IV), Rupture Disk Burst Indicators (RD BI) and to TP Cabinet
• other Control Box (CB) designs are available on request
Principle
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 100
• TP standard configuration
• Detailed TP components description
• Other TP configurations
• Retrofitting
• TP options
• TP chain value
4. TP Technical Description
4. TP Technical Description
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 101
4. TP Technical Description Other TP configurations: Horizontal Depressurization Set (HDS)
When the Vertical Depressurization Set (VDS) can not beinstalled, for example because of electrical HV clearances, theHorizontal Depressurization Set (HDS) is proposed
1
HDS Elements
1. Isolation Valve Flange (IVF)
2. Isolation Valve (IV)
3. Shock Absorber (SA)
4. Rupture Disk (RD)
5. Decompression Chamber (DC)
6. Support Plate (SP)
7. Vibration Absorber (VA)
1
2
43
76
5
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 102
4. TP Technical Description Other TP configurations: Wall & Elevated OGST
2When the conservator cannot be shared, the followingOGST configurations are proposed
Elevated Oil Gas Separation Tank – EOGSTWall Oil Gas Separation Tank – WOGST
a) with Vertical Depressurization Set (VDS)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 103
4. TP Technical Description Other TP configurations: Wall & Elevated OGST
2When the conservator cannot be shared, the followingOGST configurations are proposed
Elevated Oil Gas Separation Tank – EOGSTWall Oil Gas Separation Tank – WOGST
b) with Horizontal Depressurization Set (HDS)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 104
4. TP Technical Description Standard Configuration
3Reminder: Standard Configuration
when no specific constraints
Vertical Depressurization Set (VDS) & Slice OGST (SOGST)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 105
• TP standard configuration
• Detailed TP components description
• Other TP configurations
• Retrofitting
• TP options
• TP chain value
4. TP Technical Description
4. TP Technical Description
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 106
4. TP Technical Description Retrofitting on existing transformers
The TRANSFORMER PROTECTOR is easily retrofitted without tank machining by using the existing interfaces
1. Depressurization Set: Cover and Side Manholes, Pressure Relief Valves and Existing Valves can be used for the adaptation
SKIP
Retrofitting on existing transformers
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 107
4. TP Technical Description Retrofitting on existing transformers
The TRANSFORMER PROTECTOR is easily retrofitted without tank machining by using the existing interfaces
1. Depressurization Set: Cover and Side Manholes, Pressure Relief Valves and Existing Valves can be used for the adaptation
SKIP
Retrofitting on existing transformers
Examples:
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Retrofitting on existing transformers
108
4. TP Technical Description Retrofitting on existing transformers
The TRANSFORMER PROTECTOR is easily retrofitted without tank machining by using the existing interfaces
1. Depressurization Set: Cover and Side Manholes, Pressure Relief Valves and Existing Valves can be used for the adaptation
2. Inert Gas Injection: Existing Valves for oil sampling and draining can be used to retrofit the inert gas injection
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Retrofitting on existing transformers
109
4. TP Technical Description Retrofitting on existing transformers
The TRANSFORMER PROTECTOR is easily retrofitted without tank machining by using the existing interfaces
1. Depressurization Set: Cover and Side Manholes, Pressure Relief Valves and Existing Valves can be used for the adaptation
2. Inert Gas Injection: Existing Valves for oil sampling and draining can be used to retrofit the inert gas injection
Example:
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 110
• TP standard configuration
• Detailed TP components description
• Other TP configuration
• Retrofitting
• TP options
• TP chain value
4. TP Technical Description
4. TP Technical Description
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 111
• Option A: OLTC protection
• Option B: OCB protection
TP Options
4. TP Technical Description
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Option A : On Load Tap Changers Protection
112
4. TP Technical Description TP Options: OLTC protection
1. Rupture Disk with integrated Burst Indicator (RDBI)
2. Decompression Chamber (DC)
3. Explosive Gas Elimination Pipe (EGEP)
Elements
1
23
Example
SKIP
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Option A : On Load Tap Changers Protection
113
4. TP Technical Description TP Options: OLTC protection SKIP
The OLTC protection can be proposed with an Isolation Valve (IV) as well:
Rupture Disk with integrated Burst Indicator (RDBI)
Isolation Valve (IV)
IV Limit Switches
Decompression Chamber (DC)
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Option B : Oil Cable Boxes Protection
114
4. TP Technical Description TP Options: OCB protection
Rupture Disk with integrated Burst Indicator (RDBI)
Isolation Valve (IV)
Inert Gas Injection Pipe (IGIP)
Oil Collecting Pipe
Example :
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 115
• TP standard configuration
• Detailed TP components description
• Other TP configuration
• Retrofitting
• TP options
• TP order process
4. TP Technical Description
4. TP Technical Description
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 116
4. TP Technical Description TP order process
TP Project
TP Installation
TP Guarantee and Maintenance
TP Project
TP Installation
TP Guarantee and
Maintenance Guarantee Maintenance
Supervised
Erection
Supervised
TestsCommissioning
Research &
Development
Project
DefinitionProduction Tests
Packaging
Transport
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 117
4. TP Technical Description TP Project
Research &
Development
Project
DefinitionProduction Tests
Packaging
Transport
TP Components Selection
Engineering Drawings
Quantity Certificates
Customization
Numerical Simulation
Validation
Manufacturing
Assemblies
Methods
Factory Tests
Components Preliminary Tests
TP Logic
TP Project
Specific Packaging
Site Delivery
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 118
4. TP Technical Description TP Installation
Supervised
Installation
& Tests
Accredited Supervisor
or
SERGI Project Engineer
TP Installation
SERGI Project Engineer
included in the TP price
On-Site Test Certificate (OTC) signed by SERGI
Installation
AcceptationCommissioning
End of Installation Certificate (EIC) signed by SERGI
TRANSFORMER PROTECTORThe Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 119
4. TP Technical Description Guarantee & Maintenance
When the End of Installation Certificates and the On Site Test Certificate are signed by the SERGI Project Engineer:
12 months guarantee Liability insurance for TP life up to 3 Millions Euros per event
TP Guarantee and Maintenance
Guarantee Maintenance
The TP is a passive mechanical system
(no electric actuator)
Limited and low cost maintenance
SERGI has dedicated team for maintenance follow up
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 120
• Financial benefit
• World reference / sold TP
• Valorization & certification organisms
• Successful activations
• Installation examples
5. References
5. References
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 121
5. References Financial benefit
The TP Financial Benefit is very high
The Protection Financial Benefit (PFB) is calculated as :
PFB = CTC / (MLEB – LEA)
For corporate risk managers and insurance, if:
• PFB < 1 %, the protective technology is highly recommended
• 1% < PFB < 4%, insurance companies adjust their rates and premiums
Analyses showed that the TP Financial Benefit varies from 0.015 % to 0.06 % !
When an incident occurs, the TP compensates several thousand times the investment
• CTC (Cost To Complete) : complete price of the protection (including erection and tests)
• MLEB (Maximum Loss Expectancy Before): cost of the worst recorded incident before installing a protection
• LEA (Loss Expectancy After): evaluation of the damage cost of the worst recorded incident with the chose protection after installation
Extract from “Transformer Explosion and Fire Incidents, Guideline for
Damage Cost Evaluation, Transformer Protector Financial Benefit”
Available on request
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Generation Transmission Distribution
122
5. References Sold TP
More than 1.400 TP sold since 2000
Every kind of oil-filled transformers (above 1 MVA)
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 123
5. References End users
More than 106 companies in 53 countries:
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 124
5. References NFPA
• Standard NFPA 850 (Recommended Practice for Fire Protection for Electric Generating Plants and High Voltage Direct Current Converter Stations)
• Standard NFPA 851 (Recommended Practice for Fire Protection for Hydroelectric Generating Plants)
The NFPA recommends the TP
In the introduction of NFPA 850 and 851:
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 125
5. References NFPA
Definition of “fast depressurization system” by the NFPA:
• Standard NFPA 850 (Recommended Practice for Fire Protection for Electric Generating Plants and High Voltage Direct Current Converter Stations)
• Standard NFPA 851 (Recommended Practice for Fire Protection for Hydroelectric Generating Plants)
The NFPA recommends the TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 126
5. References NFPA
Explanation of the operation by the NFPA:
• Standard NFPA 850 (Recommended Practice for Fire Protection for Electric Generating Plants and High Voltage Direct Current Converter Stations)
• Standard NFPA 851 (Recommended Practice for Fire Protection for Hydroelectric Generating Plants)
The NFPA recommends the TP
Documents available on
request
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 127
5. References NFPA
• The TP is also mentioned in the NFPA Fire Handbook 2002 & 2008
The NFPA recommends the TP
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 128
FM Global : Certification under progress
EDF (Electricité de France) and CEPEL (Brazil) laboratories TP tests validation
Active participation in the Power Transformer Subcommittee (tank rupture mitigation taskforce)
Various IEEE Conferences
Active participation in the A2 Study Committee –Transformers (transformer fire safety practices WG)
Various Cigré Conferences
5. References Valorization or certification organisms
ISO 9001 Certification
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 129
5. References Successful activations
• Romania (TransElectrica),
• Philippines (Transco),
• Botswana (Botswana Power Corporation),
• Activation in Pakistan, Mexico (3) and Romania under process
The TP saved transformers, successful activation certificates from:
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
France, Randens Hydro Power Plant, Electricité de France
Namibia, Van Eck Substation, NamPower
130
5. References Installation examples
Qatar, Al Jumaliah, Al Waab, Alkor Jonction…, transmission substations
Brazil, Assis Substation, São Paulo
Australia, Mount Piper, Coal Power Plant, Delta Electricity
SKIP
Installation on new transformers
Retrofitting on existing transformers
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 131
Installation:
5. References Installation examples
Qatar, transmission substation, ~ 80 transformers (20 to 315 MVA)
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Qatar, transmission substation, ~ 80 transformers (20 to 315 MVA)
132
Main tank Depressurization Set:
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Qatar, transmission substation, ~ 80 transformers (20 to 315 MVA)
133
On Load Tap Changers Protection:
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Qatar, transmission substation, ~ 80 transformers (20 to 315 MVA)
134
Oil Cable Boxes Protection:
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Qatar, transmission substation, ~ 80 transformers (20 to 315 MVA)
135
Inert gas injection:
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Qatar, transmission substation, ~ 80 transformers (20 to 315 MVA)
136
TP Cabinet:
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Qatar, transmission substation, ~ 80 transformers (20 to 315 MVA)
137
Control Boxes in the control room (for 11 transformers)
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Brazil – Assis Substation – São Paulo
138
Overview
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Brazil – Assis Substation – São Paulo
139
DS for the main tank OLTC Protection TP Cabinet
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Australia – New South Wales Coal Power Plant – Delta Electricity
140
Overview of the power plant
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Australia – New South Wales Coal Power Plant – Delta Electricity
141
Installation of the TRANSFORMER PROTECTOR
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
France – Randens Hydro Power Plant – Electricité de France
142
Complex situation in a tiny cave
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
France – Randens Hydro Power Plant – Electricité de France
143
Technical proposal
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
France – Randens Hydro Power Plant – Electricité de France
144
Installation
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Namibia – Van Eck Substation – NamPower
145
Vertical DS for the main tank and 3 OLTC protection
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e
Namibia – Van Eck Substation – NamPower
146
Vertical DS for the main tank 3 OLTC protections
5. References Installation examples
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
1/ Transformers explosions
2/ TP principle
3/ Physical explanations
4/ Technical description
5/ TP References
Ref: FtTPgaac31e 147
Conclusion
• The NFPA recommends the TP• Several successful activations• More than thousand TP sold all over the world (USA, Europe, Middle East…)
3. The TP is a recommended solution
• Principle: No Actuator !The TP is activated by the first dynamic pressure peak generated by the arc, avoiding the explosion by preventing static pressure increase
• Efficiency demonstrated by experimental tests & numerical simulations
2. The TRANSFORMER PROTECTOR prevents the explosion
• Explosions are more and more frequent• Dangerous, expensive, polluting, hurt reputation…• Conventional corrective means do not prevent explosion (fire extinguishing
systems, firewalls)• Conventional preventive means are not efficient (circuit breakers, buchholz, PRV...)
1. Power transformers are very dangerous
During a transformer short circuit, the TRANSFORMER PROTECTOR is activated within milliseconds by the first
dynamic pressure of the shock wave, avoiding transformer explosions before static pressure increase
TRANSFORMER PROTECTOR
The Only Solution Against Transformer Explosion
www.sergi-france.com
SERGI186 av. du Général de Gaulle – PO Box 90
78260 Achères – France
: 33 1 39 22 48 00
: 33 1 39 22 11 11
@ : sergi@sergi-france.com
web site : www.sergi-france.com