Review of Important Diagnostics Parameters for Power Transformer

Transformer is one of the most important and costly apparatus in a power system. The reliable and efficient fault free operation of transformer has a decisive role in the availability of electricity supply. In recent years, there has been growing interest in the condition assessment of transformer insulation. In this paper we concerned about the condition monitoring of transformer, benefit of condition monitoring. Many diagnostics methods are available in literature such as Dissolved gas analysis (DGA), tan delta (tan δ), resistivity, furan analysis, breakdown voltage (BDV), partial discharge (PD), frequency response analysis (FRA), moisture (oil & paper) etc. In this paper some of the diagnostic technique and analysis techniques have been reviewed. The dielectric diagnostic methods are required to understand the effect of various stresses such as thermal, electrical etc. on the transformer insulating oil.