Analysis of Transformer Insulation by Tan Delta Testing Method


Dipak Mehta
Hitesh R. Jariwala


This paper presents analysis of power transformer insulation by one fundamental insulation power factor test, also known as Tan Delta. It is a routine test conducted at site to know the healthiness of insulation in transformers. Out of 108 transformers tested for research work, case studies were chosen for analysis purpose. Experimental data shows our experience on the measurement of Tan Delta techniques of earthing systems and dryness of insulation in transformers. Result shows that the Tan Delta testing method is very effi cient method.


How to Cite
Mehta, D., & Jariwala, H. R. (2012). Analysis of Transformer Insulation by Tan Delta Testing Method. Power Research - A Journal of CPRI, 31–40. Retrieved from


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