A Novel Technique for Partial Discharge Localization in Transformer Winding Based on Archimedean Copula

Summary

Partial discharge (PD) is the primary source of insulation degradation in power transformer and accurate determination of the PD location in transformer winding is important for maintenance and preventing catastrophic failure at an early point. The precise position of PD in transformer winding is quite hard due to extremely complex and non-uniform structure of the transformer winding. A copula-based technique is proposed to find the exact location of PD in transformer winding. The winding response for voltage pulse of known pulse width is applied across various sections in lumped transformer winding model which is taken as reference data. Likewise, the winding response obtained from voltage pulse with different pulse width applied across various winding sections is taken as test data. The different Archimedean copulas are studied and the parameters of the copula are obtained. Then the best fit copula to the PD data is obtained. With the help of best-fit copula, the log-likelihood is determined between the reference data and the test data. The maximum log-likelihood gives the location of PD. The results of proposed method are then compared with time-domain correlation techniques. The simulation results demonstrate that the proposed approach is capable of achieving accurate prediction of location of PD source. The copula method is advantageous in examining the scale-free dependence while saving the dependence during simulation.

Additional informations

Authors

He Wenlin, Dong Xuesong