Luiz Cheim, Lan Lin - IEEE Fall Meeting - Milwaukee 10/23/2012 IEEE C Revision (Nov 2011) TF Database Analysis TF Database Analysis Luiz Cheim and Lan Lin ABB 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 incorporated 2. Discussed unknown oil preservation system 3. Question of Rate of Gas Formation vs Levels

Montreal Meeting (May 2o12) Revisited Percentiles with Following Condition: O2/ (N2 + O2) 70,000 => N2 Blanket 5 – 15% Membrane/Rubber Bag > 15% Open Breather

Legend (next slides) IEEECondition 1 Limit CigreTypical Value (Brochure SCD1.32, 2010) AFMoArc Furnace, 90th Percentile (mineral oil) AFSiArc 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, 90 th Percentile – Per MVA Rating IEEE AFMo AFSi Cigre

H2, 90 th Percentile – Per Age Group IEEE AFMo AFSi Cigre

C2H6, 90th Percentile – Per Voltage Class Cigre

Revision C – TF on Data Analysis Gas Rate Subject 1. Should we calculate rates percentiles for all gases? 2. Should we associate rates to levels? How? 3. Cigre recent experience

Revision C – TF on Data Analysis Cigre Levels vs Sampling Intervals Cigre SCD1.32 Brochure, December 2010

Revision C – TF on Data Analysis Cigre Rates vs Sampling Intervals Cigre SCD1.32 Brochure, December 2010

Revision C – TF on Data Analysis Cigre SCD1.32 Brochure December 2010

Revision C – TF on Data Analysis Proposal Under Discussion – Level vs Rate Frequency of DGA

Revision C – TF on Data Analysis Proposal Under Discussion – Level vs Rate Severity of Fault (?)

Revision C – TF on Data Analysis Gas Rates (IEEE Database)

Revision C – TF on Data Analysis Gas Rates (IEEE Database)

Revision C – TF on Data Analysis Gas Rate Issues days

Revision C – TF on Data Analysis Gas Rate Issues days

Revision C – TF on Data Analysis Gas Rate Issues  ± 15% Cigre Typical Lab Accuracy 133 days

Revision C – TF on Data Analysis Gas Rate Issues days 68 ?

Revision C – TF on Data Analysis Gas Rate Issues

Revision C – TF on Data Analysis Another Example

Revision C – TF on Data Analysis Another Example 27 ppm/year 500 ppm/year

Revision C – TF on Data Analysis Inherent Uncertainty in Trend Calculation 1. Multiple Laboratories 2. 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 C – TF on Data Analysis Distribution of DGA Sampling Interval

Revision C – TF on Data Analysis Distribution of DGA Sampling Interval

Revision C – TF on Data Analysis Distribution of DGA Sampling Interval

Revision C – TF on Data Analysis Gas Rates Distribution vs DGA Sampling Interval

Revision C – TF on Data Analysis Gas Rates Distribution vs DGA Sampling Interval

Revision C – TF on Data Analysis Gas Rates Distribution vs DGA Sampling Interval

Revision C – TF on Data Analysis Gas Rates Distribution vs DGA Sampling Interval

Revision C – TF on Data Analysis Gas Rates Distribution vs DGA Sampling Interval

Revision C – TF on Data Analysis Gas Rates Distribution vs DGA Sampling Interval

Revision C – TF on Data Analysis Gas Rates Distribution vs DGA Sampling Interval 38%

Revision C – TF on Data Analysis Rates Distribution vs DGA Sampling Interval

Revision C – TF on Data Analysis

Revision C – TF on Data Analysis

Food for Thought!

Revision C – TF on Data Analysis Proposal for Discussion – Level vs Rate Severity of Fault (N2 Blanket, etc) 90 th |  t 95 th |  t … Table conditioned to  t = Sampling Interval

Revision C – TF on Data Analysis Rate of Gas Increase vs Sampling Interval???

Revision C – TF on Data Analysis Rate of Gas Increase vs Sampling Interval???

Revision C – TF on Data Analysis Rate of Gas Increase vs Sampling Interval??? Food for Thought…