Luiz Cheim, Lan Lin - IEEE Fall Meeting - Milwaukee 10/23/2012

IEEE C57.104 Revision (Nov 2011)

TF Database Analysis Luiz Cheim and Lan LinABB Inc.

Building the Database

+ HQ= 521,700 records

Transformers Age Groups

Transformers Power Ratings

Transformers Voltage Classes

Transformers Oil Preservation Type

Reason for DGA

Percentiles of Hydrocarbons (all data)

%

ppm

Percentiles of CO,CO2 and TDCG (all data)

%

ppm

Percentiles of H2, C2H2 and CO vs. Age Groups

%

ppm

Percentiles of H2, C2H2 and CO vs. Voltage Class

%

ppm

Percentiles of H2, C2H2 and CO vs. Power Ratings

%

ppm

Percentiles of H2, C2H2 and CO vs. Source of Data

%

ppm

Percentiles of All Gases (Suspicious Units)

%

ppm

Percentiles of H2, C2H2 and CO vs. Power Ratings(Suspicious Units)

%

ppm

Percentiles of H2, C2H2 and CO vs. Voltage Class(Suspicious Units)

%

ppm

Percentiles of H2, C2H2 and CO vs. Oil Preservation

%

ppm

Annual Rate of Gas Formation (ppm/year)Percentiles of All Gases

%

ppm

After that…

1. HQ Data incorporated2. Discussed unknown oil preservation system3. Question of Rate of Gas Formation vs Levels

Montreal Meeting (May 2o12)

Revisited Percentiles with Following Condition:

O2/ (N2 + O2) < 5% and N2 > 70,000 => N2 Blanket5 – 15% Membrane/Rubber Bag> 15% Open Breather

Legend (next slides)

IEEE Condition 1 LimitCigre Typical Value (Brochure SCD1.32, 2010)AFMo Arc Furnace, 90th Percentile (mineral oil)AFSi Arc Furnace, 90th Percentile (Silicon oil)

H2 – All Data

IEEE

AFMo

AFSi

Cigre

CH4 – All Data

IEEE

AFMo

AFSi Cigre

C2H2 – All Data

IEEE

AFMo

AFSi

Cigre

C2H4 – All Data

IEEE

AFMo

AFSi

Cigre

C2H6 – All Data

IEEE

AFMo AFSi

Cigre

CO – All Data

IEEE

AFMo

AFSi = 1936

Cigre

CO2 – All Data

IEEE

AFMo

AFSi = 25,387

Cigre

TDCG – All Data

IEEE

AFMo

AFSi = 2,160

Cigre

Further Breakdown…

Given a type of oil preservation (say, N2 Blanket)

What happens to Gas Levels vs Voltage Class, MVA, Age?

H2, 90th Percentile – Per Voltage Class

IEEE

AFMo

AFSi

Cigre

H2, 90th Percentile – Per MVA Rating

IEEE

AFMo

AFSi

Cigre

H2, 90th Percentile – Per Age Group

IEEE

AFMo

AFSi

Cigre

C2H6, 90th Percentile – Per Voltage Class

Cigre

Revision C57.104 – TF on Data AnalysisGas Rate Subject

1. Should we calculate rates percentiles for all gases?

2. Should we associate rates to levels? How?3. Cigre recent experience

Revision C57.104 – TF on Data AnalysisCigre Levels vs Sampling Intervals

Cigre SCD1.32 Brochure, December 2010

Revision C57.104 – TF on Data AnalysisCigre Rates vs Sampling Intervals

Cigre SCD1.32 Brochure, December 2010

Revision C57.104 – TF on Data AnalysisCigre SCD1.32 Brochure December 2010

Revision C57.104 – TF on Data AnalysisProposal Under Discussion – Level vs Rate

Frequency of DGA

Revision C57.104 – TF on Data AnalysisProposal Under Discussion – Level vs Rate

Severity of Fault (?)

Revision C57.104 – TF on Data AnalysisGas Rates (IEEE Database)

t

ppm

Revision C57.104 – TF on Data AnalysisGas Rates (IEEE Database)

Revision C57.104 – TF on Data AnalysisGas Rate Issues

72

115

133 days

dayppmt

ppm/323.0

133

72115

Revision C57.104 – TF on Data AnalysisGas Rate Issues

72

115

133 days

yearppmt

ppm/118

133

72115

Revision C57.104 – TF on Data AnalysisGas Rate Issues ± 15% Cigre Typical Lab Accuracy

133 days

yearppmt

ppm/41

133

8398

Revision C57.104 – TF on Data AnalysisGas Rate Issues

72

115

343 days

yearppmt

ppm/50

343

11568

68

?

Revision C57.104 – TF on Data AnalysisGas Rate Issues

yearppmt

ppm/5.13

Revision C57.104 – TF on Data AnalysisAnother Example

Revision C57.104 – TF on Data AnalysisAnother Example

27 ppm/year

500 ppm/year

Revision C57.104 – TF on Data AnalysisInherent Uncertainty in Trend Calculation

1. Multiple Laboratories2. Lab Variations (repeatability, reproducibility, accuracy)

3. Seasonal variations (temperature, etc)

4. Sampling errors (humans, sample contamination, etc)

5. Type of Transformer (N2, etc…)

6. Sampling interval??

Revision C57.104 – TF on Data AnalysisDistribution of DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisDistribution of DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisDistribution of DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisGas Rates Distribution vs DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisGas Rates Distribution vs DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisGas Rates Distribution vs DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisGas Rates Distribution vs DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisGas Rates Distribution vs DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisGas Rates Distribution vs DGA Sampling Interval

Revision C57.104 – TF on Data AnalysisGas Rates Distribution vs DGA Sampling Interval

38%

Revision C57.104 – TF on Data AnalysisRates Distribution vs DGA Sampling Interval

Revision C57.104 – TF on Data Analysis

53

204

Revision C57.104 – TF on Data Analysis

Revision C57.104 – TF on Data Analysis

Revision C57.104 – TF on Data Analysis

Revision C57.104 – TF on Data Analysis

Revision C57.104 – TF on Data AnalysisFood for Thought!

Revision C57.104 – TF on Data AnalysisProposal for Discussion – Level vs Rate

Severity of Fault (N2 Blanket, etc)

90th | t 95th | t …

Table conditioned to t = Sampling Interval

Revision C57.104 – TF on Data AnalysisRate of Gas Increase vs Sampling Interval???

Revision C57.104 – TF on Data AnalysisRate of Gas Increase vs Sampling Interval???

Revision C57.104 – TF on Data AnalysisRate of Gas Increase vs Sampling Interval???

Food for Thought…