The Wavelet-Based Filtering Method as an Alternative to k-Factor Filtering for High-Voltage Impulse Signals

This paper deals with a new method of evaluating lightning impulse voltage parameters. For this purpose, three different types of impulse signals were used for analysis. The main point of the study focuses on the k-factor and wavelet transform methods to attenuate oscillations and overshoots that occur in impulse voltages. In this manner, as an alternative method to the k-factor approach, which is proposed in the IEC Standard 60060-1, the wavelet-based filtering approach is presented and its last approximation sub-band is described as de-noised data. Under the comparisons of the calculated signal parameters, the wavelet application was found to be a powerful method as much as the k-factor filtering in terms of a mathematical solution to the related problem.