Feasibility of Partial Discharge Localization in Power Transformers based on a novel Curve Fitting Method

This contribution focuses on feasibility of partial discharge (PD) localization for power transformers based on a novel curve fitting coefficient method. The measured partial discharge waveforms by high frequency current transformer (HFCT) are processed using the sinusoidal curve fitting (CF) method with a high rated fitting quality. The extracted coefficients of the selected function terms are then evaluated in order to find the location of the PD. The proposed method is implemented on the high voltage winding of a lab-transformer to verify its applicability and accuracy. The experiment is comprised of injecting PD pulses into different points along the winding and applying the proposed localization algorithm. Afterwards, error ranges are provided to evaluate the accuracy of the method. The proposed method is based on analyzing the PD waveforms, which could be obtained from two sides of the high voltage winding of power transformers using high frequency current transformers. The curve fitting coefficient method and complementary measured results are presented and discussed comprehensively in this paper. In this study, a novel curve fitting coefficient method is proposed in order to localize PD in power transformers. Furthermore, the feasibility of applying this method is discussed in details, which show that this method could be used for PD localization in power transformers.