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Mathieu Guertin Director – Europe, Russia and Africa Morgan Schaffer Inc. Canada A cost effective strategy for smart grid technology adoption
Mathieu Guertin Director – Europe, Russia and Africa
Morgan Schaffer Inc. Canada
A cost effective strategy for smart grid technology adoption
Why protecting assets?
Cost of fault: $52 MILLIONS!!!
http://www.cbc.ca/money/story/2010/07/07/alcan-explosion.html http://ca.news.finance.yahoo.com/s/14102010/2/biz-finance-quebec-aluminum-smelter-explosion-cost-rio-tinto-alcan.html
…Easy ROI calculations for
transformer dissolved gas monitoring…
Accuracy
Combustible Gas Generation rates
3 key learnings…
Accuracy
DGA Understanding process and operations
Sampling techniques & location
jar
syringe
Multiple and varied steps
Hard to control variables
Multiples operators along the complet analysis process
Sampling point
Packaging & handling
Transportation Sample preparation
Gas extraction
Gas separation and
measurement
Accuracy
Your DGA results: Accurate or not?
Every Laboratory should be able to demonstrate their precision and accuracy, if this is not possible or by any reason unknown, the below chart is recommended to use as a guide
Accuracy of IEC/CIGRE laboratories, from round-robin tests using DGA standards.
Medium gas concentrations
Low gas concentrations
Best lab ±3% ±22%
Average ±15% ±30%
Worst Lab ±65% ±64% IEEE August 2005, M. Duval, J. Dukarm, Improving the reliability of transformer in gas-in-oil diagnosis
Accuracy
Your DGA results: Accurate or not?
IEEE August 2005, M. Duval, J. Dukarm, Improving the reliability of transformer in gas-in-oil diagnosis
Diagnostic reliability is affected by the accuracy of the DGA measurement results
CIGRE result for Round Robin Test (RRT) at low concentration levels.
. Results of individual laboratories
x prepared DGA standard value ()
+/- 15% variation limit of absolute values
Accuracy
DGA as a tool
From Information…
…to Action
Accuracy
Diagnosing transformer condition
A good rule is: Never make a decision based only on a ratio if either of the two gases used in a ratio is less than 10 times the amount the gas chromatograph can detect FIST 03-30, USA Bureau of reclamation
Accuracy
Diagnosing transformer condition
TDG (Total Dissolved Gases) expressed in % to 1.000.000ppm, i.e. in the picture TRN1 we see 7%, meaning there is a total of 70.000 ppm of gases (all the gases) TDCG (Total Dissolved Combustible Gases) all the gases except N2, O2 and CO2, also in % to 1.000.000ppm, that’s why we see 0% (less than 1ppm, as almost all the gases are N2, O2 and CO2) THCG (Total Headspace Combustible Gases) are the gases on the headspace at the transformers (especially in sealed transformers with N2 blanket) as the gases dissolved in the oil are in equilibrium with the headspace, we calculate, based on the Ostwald coefficient, each gas at the headspace level.
Accuracy
Diagnosing transformer condition
The Duval Triangle method, like any other DGA diagnostic method, should be applied only when there is some suspicion of a fault, based on an increase in combustible gas or some other suspicious symptom. The diagnostic method itself is not a means of fault detection. Because of the relative inaccuracy of gas-in-oil concentration measurements at low concentrations, DGA diagnostic methods, including the Duval Triangle, should not be applied unless the gas concentrations are well above the detection limit. If reasonably stable concentrations of the gases were present before the onset of the suspected fault, it is advisable to subtract out the background concentrations, provided that the differences are large enough for interpretation. The diagnosis should be based on recently-formed gas if possible, and including pre-fault gas in the diagnostic calculations can lead to misleading results2.
1 PPMreport, Morgan Schaffer Myrkos’s operating system 2 http://www.deltaxresearch.com/triangle.htm
1
Accuracy
Diagnosing transformer condition
Rogers used these relationships and determined that if a certain ratio existed, then a specific temperature had been reached. By comparing a large number of transformers with similar gas ratios and data found when the transformers were examined, Rogers could then say that certain faults were present. Like the Key Gas Analysis above, this method is not a “sure thing” and is only an additional tool to use in analyzing
transformer problems. FIST 03-30, USA Bureau of reclamation
Accuracy
Summary of gases used by the diagnostics tools
Accuracy
IEEE test: H2 CH4 C2H2 C2H4 C2H6 CO CO2
Duval test: CH4 C2H2 C2H4
Rogers test: H2 CH4 C2H2 C2H4 C2H6
Doerneburg H2 CH4 C2H2 C2H4 C2H6
CO2/CO CO CO2
Standards tests support the decision making process
1) What is the current situation of the transformer?
2) What is the nature and severity of the fault?
Operationalizing
and integrating
Accuracy
And being SMART about it
Ability to Monitor the Evolution of the Condition = Monitoring Value.
Transformers monitoring: 3 key values
Ability to Detect a change in condition In ALL cases = Protection Value.
Ability to Diagnose the nature of the “bad” condition = Diagnostic Value.
Value no.1
Value no.2
Value no.3
Accuracy
Defining the needs…
# of Gases analyzed
Dia
gn
ost
ic v
alu
e
2) Defining Asset Criticality
Accuracy
1) Review current resources & operations
4) Plan & budget
5) Implement, deploy, and integrate
3) Review needs
Detect
Monitor
Diagnostic
Transformer Condition evolution – economical costs
$ Best Case
Worst Case $$$$
Time
Accuracy
Transformer: Electrical network
$
Time
Significant savings occur when a large number of transformers are being monitored
The Global Picture
Failures will happen… it’s a matter of probability!!
Accuracy
Monetizing Online monitoring
Monitoring Value : Approx. 10 000 €
Diagnostic Value : Approx. 30 000 €
Monitoring Value : 0 €
Diagnostic Value : 0 €
Detection Value : Approx. 10 000 €
Monitoring Value : 0$
What you actually pay for
10 Years
If no problem arises during the life of the transformer, only the Detection value of
the instrument is of benefit.
Accuracy
Monetizing Online monitoring
10 000 € 0€
Condition change
10 Years Detection Value
Monitoring Value
Diagnostic Value
When a condition change occurs, Diagnostics capabilities are important, but otherwise only
Detection and/or Monitoring
30 000 €
10 000 €
Diagnostic Value
0€
Monitoring Value
Condition change : better allocation of budget
Accuracy
Deploying online monitors Maximizing coverage of electrical assets
Critical 2
Critical 1
Sub-station
So when a transformer’s condition
changes abnormally…
Detect
Monitor
Diagnose
New
Deploying online monitors Alarm
Critical 2
Critical 1
Sub-station
1
Evolving fault triggers a signal to substation for action
Detect
Monitor
Diagnose
New
Accuracy
Deploying online monitors Alarm triggers on-site inspection and Myrkos DGA
Critical 2
Critical 1
Sub-station
1
2
Field team quickly addresses the alert On-site AND channels the DGA results.
Communicate with Asset Manager for DGA-based action plan
<<<< 1 day to provide results for
diagnostics by Asset manager
Detect
Monitor
Diagnose
New
or Lab DGA
Accuracy
Deploying online monitors
Critical 2
Critical 1
Sub-station
After condition assessment and decision taken on “faulty” transformer
On-site Condition assessment
When needed : on-line multigas monitor for problematic/concerning fault gases evolution (temp/perm)
1
2
3
ASTM D3612 IEC 60567
Detect
Monitor
Diagnose
New
Multigas can be used effectively to closely monitor transformer
Accuracy
Deploying online monitors
Critical 2
Critical 1
Sub-station
Detect
Monitor
Diagnose
New
Budget allocation efficiency
Critical 2
Critical 1
Detect
Monitor
Diagnose
New
A B
1x 3-4X
Accuracy
Deploying online monitors
Critical 2
Critical 1
Sub-station
Detect
Monitor
Diagnose
New
@ equal budget
Critical 2
Critical 1
Detect
Monitor
Diagnose
New
A B
Equal budget
Sub-station
- Extended coverage - Diagnostics - Easier data management
A B
Accuracy
Interchangeability concept: key pointers Maximizing coverage of electrical assets
Critical 2
Critical 1
Detect
Monitor
Diagnose
Aiming for minimal downtime Leveraging the current infrastructure Maximizing monitoring value while maintaining Accuracy
Accuracy
Balancing values: interchangeability concept in action
Accuracy
Interchangeability concept in action: from a detection monitor alarm, to multigas diagnostics
Details : This case study is about 18.4/23 MVA power transformer, 19/6.3 kV, Dyn1, manufactured in 2010. Early in 2013, the Calisto 2 monitor installed on the transformer detected an increase on the H2 values. The Calisto 2 was replaced with a Calisto 9 for further investigation (interchangeable units)
Interchangeability concept From Detection
To Diagnostics
Normal operation
**Change in condition
Accuracy
Interchangeability concept in action: from a detection monitor alarm, to multigas diagnostics
Accuracy
Details : The Calisto 9 measured high values were recorded for H2, C2H4, C2H6 and most importantly for C2H2. The measurements were double checked by the customer: Samples were sent to ABB Sweden for DGA and all measurements were confirmed. Electrical measurements were performed locally and the winding resistance measurements (static and dynamic) showed a loose contact of one winding with the OLTC selector.
Interchangeability concept in action: from a detection monitor alarm, to multigas diagnostics
Accuracy
Interchangeability concept in action: from a detection monitor alarm, to multigas diagnostics
Accuracy
Duval Triangle
1) Adjusted for the actual oil type used in the transformer
2) 2nd level analysis with Triangle no.4 and no.5
3) Only triggered when proper gas alarm limits have been reached, reducing false positive
Interchangeability concept in action: from a detection monitor alarm, to multigas diagnostics
Accuracy
Additional diagnostics
1) Rate of change (Day, Week, Month, Year)
2) Rogers ratios 3) IEC 60599 4) Doernenburg 5) Key gas method 6) IEEE
Interchangeability concept in action: from a detection monitor alarm, to multigas diagnostics
Accuracy
Details : The transformer was opened, the oil was removed and the loose contacts were indeed found and fixed. Measurements from the Calisto 9 shown on the previous slide demonstrate the situation has stabilized after the problem had been fixed. The customers expressed their satisfaction regarding the early warning they received from the Calisto 2 that allowed them to fix the problem at no practical cost.
The loose contacts were one of the connecting points of the transformer windings with the OLTC tap positions. These contacts are located inside the transformer tank, not the OLTC tank
Process excellence: empowering the field On-site Dissolved Gas Analysis
Un
stab
le H
2 co
nd
itio
n
?
Alert
On-site visit / visual inspection
Ton-site/sampling Tpacking/shipping/customs Tlab analysis
1-10 Hours 1-10 Hours 1-5 days 1-5 days
Tresults/condition assessment/decision
Critical early detection in H2 change
X X X
Elimination of time consuming and wasteful steps
Speed of reaction to particular event: field DGA
Un
stab
le H
2 co
nd
itio
n
?
Critical early detection in H2 change
Alert
On-site visit / visual inspection
Ton-site/sampling Ton-site DGA/ immediate result
Tlab analysis
1-10 Hours 0.1 Hours 1-5 days
Diagnose
PLUS… with MYRKOS you
tremendously increase your
Process excellence: empowering the field On-site Dissolved Gas Analysis
Up to 98%* reduction in Cycle time = faster results = more up time
* When normal cycle takes 2.5 months
