The oil - paper insulation reliability estimation of 420 kV transformer concerning thermal stresses during exploitation conditions
The calculating of reached ageing based on the history of loading according of International Electrotechnical Commission standard algorithm is the first task. In order to verify the obtained results, measurements of polymerization index were made on 28 paper samples taken directly from low...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
VINCA Institute of Nuclear Sciences
2016-01-01
|
| Series: | Thermal Science |
| Subjects: | |
| Online Access: | http://www.doiserbia.nb.rs/img/doi/0354-9836/2016/0354-98361600003A.pdf |
| Summary: | The calculating of reached ageing based on the history of loading according
of International Electrotechnical Commission standard algorithm is the first
task. In order to verify the obtained results, measurements of
polymerization index were made on 28 paper samples taken directly from low
voltage terminals (winding ends) and bus connections of the transformer
under test rated 380 MVA, 2´15,75 kV/420 kV. The complete procedure of paper
sample locations and taking off is described, thereby providing a manner of
how this should be done, determined by specific conditions of the
transformer under test. Furthermore, the determination of limit viscosity
and using its relationship function with polymerization index are explained
together. Comparison is made with those of liquid chromatography of oil. The
results of particle sort and size analysis are shown. Finally, an estimation
of the transformer life remainder is made, which is of paramount importance
when defining the steps that have to be made either in revitalization
process or in transformer replacement planning. |
|---|---|
| ISSN: | 0354-9836 2334-7163 |