@conference{10902/27938,
year = {2022},
url = {https://hdl.handle.net/10902/27938},
abstract = {The deterioration of the insulation in the windings of power transformers affects their lifespan. A commercial insulated Continuously Transposed Conductor (CTC) was studied experimentally, numerically and analytically. The purpose was to understand the mechanisms governing the mechanical failure of the insulating paper, and to achieve a criterion for predicting failure under different conditions. Samples of that insulated CTC were extracted from a coil and aged at 150∘C for different durations inside vessels filled with naphthenic oil. Then the degree of polymerisation and tensile, compressive and shear mechanical properties of the insulation were measured/estimated. Aged insulated CTC samples were subjected to three-point bending tests, producing deformations compatible with a short circuit, and the fractures in the insulation were analysed. The bending test over a CTC sample was simulated by means of a FEM Program. The Norris failure model, applicable to a lamina, was adapted to the studied insulation materials. The predictions of that failure criterion agreed with experimental observations.},
publisher = {Institute of Electrical and Electronics Engineers, Inc.},
publisher = {IEEE 4th International Conference on Dielectrics (ICD): procceedings, Palermo, Italy, 2022, 813-816},
title = {A modification of the Norris failure criterion for the prediction of the mechanical failure of the aged paper insulation in the windings of a power transformer},
author = {Oria Alonso, Carmela and Ferreño Blanco, Diego and Carrascal Vaquero, Isidro Alfonso and Ortiz Fernández, Alfredo and Fernández Diego, Inmaculada},
}