In search of more effective ways of representing dielectric test data for condition assessment of transformer insulation

Condition monitoring of transformer insulation have gained immense importance in the recent past. Dielectric testing techniques are being assessed as supplement to traditional techniques by researchers and utilities. Dielectric tests on transformer insulation, though simple in implementation, is not so straight forward in interpretation. Analysis of dielectric response measurement results have so far been done on the basis of either time domain or frequency domain representation of test data. Inferences about condition of the insulation have been drawn from either Polarization & Depolarization Current (PDC), or Recover Voltage (RV) or Frequency Domain Spectroscopy (FDS) measurement plots. The huge volume of test data available needs proper processing and effective presentation so as to enable the viewer to be able to analyze further. The present article attempts to look for new ways of presenting the dielectric response test data with the aim of studying the effect of condition of insulation on the measurement results.