Identification of Power Transformer Insulation Condition Sensitive Parameters using Initial Slope of RVM

Power transformers are one of the critical components of the Power System. Insulation failure is the major cause of transformer breakdown. Hence, proper insulation diagnosis is important for the reliable operation of a power system. Most of the available methods for the assessment of transformer insulation condition involves the use of costly equipment. In this work, a technique for estimating power transformer insulation condition sensitive parameters has been proposed that utilizes the Return Voltage Measurement (RVM) data measured using low-cost equipment. RVM is a known technique for the condition assessment of power transformer insulation. Here, a method is proposed to estimate insulation resistance, paper moisture and zero of the transfer function using the initial slope of the RVM spectra.