TRANSFORMER WINDING FAULTS - A NOVEL APPROACH OF RECOGNITION

The purpose of lighting impulse test is to ascertain whether the transformer insulation can withstand the non-linear electric stresses without damage and test the dielectric integrity provided. A standard lightning impulse of standard wave shape 1.2/50μs is applied to the test transformer to check its dielectric integrity. This proposed method elucidates a novel approach of identifying the healthiness of insulation. The objective of this research is to provide information about the healthiness of the insulation to the test engineer during the process of LI test against faults such as inter turn and inter disc faults. The researchers have used the original version of Probabilistic Neural Network for obviating the need of experts for recognition of faults that has taken place. For this experimental test were carried out on a 315kVA, 11kV/433 V star /delta transformer. Tapping were provided on one HV winding for simulating various inter turn and inter disc faults. Several approaches were attempted and results observed were encouraging. It is argued by the authors in this paper that this approach can be effectively used for diagnosis against winding faults [08].