Physics of Winding Deformation in Power Transformer

Abstract

Power transformers are the most expensive and critical component of our power system. Its failure would
be a costly event. Winding deformation is caused mainly due to short circuit events, other reasons may be ageing of
insulation, and mechanical stresses developed due to transportation. Although, deformation may not result in
immediate failure, however the dielectric strength of the winding is greatly reduced. And a further untoward short
circuit faults may result in complete rupture of insulation which will result in complete damage of the winding. To
prevent permanent damage of the transformers, a routine diagnosis is necessary for detection of winding deformation.