Transformers Magazine, Vol. 4 No. 3, 2017.
Original scientific paper
Transformer lifecycle: Short-circuit withstand capability of power transformers – Part II
René Smeets
Abstract
This article discusses verification of the ability of a transformer to survive short circuit. Fault current leads to large axial and radial forces on windings, which have to be managed by proper structural design. Test experience, showing a failure rate of 20-25 % of well-prepared transformers, suggests that the highest degree of reliability with respect to short-circuit withstand verification is ensured through full-scale testing in accordance with the international standards. The prime failure mode is winding deformation, but many other deficiencies, which would not be discovered in a design review, have also been observed.
Keywords
transformer; short circuit; testing; certification; reliability
Hrčak ID:
202460
URI
Publication date:
8.7.2017.
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