Correlation analysis of partial discharge measurement results

In the paper correlation analysis of partial discharge (PD) measurement results achieved using conventional electrical method and ultra-high frequency (UHF) method is presented. All measurements are proceeded under laboratory conditions on various PD model sources immersed in an insulation oil. Typical measuring system commonly used for electrical power transformers PD diagnostics is applied in the research. Supply voltage level as well as PD generating spark gap configuration and UHF measurement frequency band influence on correlation coefficients between registered physical quantities are investigated in the paper. Furthermore an aggregate comparative analysis of achieved results is presented which points out that correlation coefficients between registered apparent charge and UHF voltage results are in most cases higher than 0.8. Finally announced research results further practical application possibilities in fields of real life insulation systems PD diagnostics are proposed in the paper.