Multi-resolution wavelet analysis for chopped impulse voltage measurements and feature extraction

In this study, an application of the wavelet transform based on the multi-resolution analysis (MRA) is aimed for evaluation of amplitude and time parameters of the chopped impulse voltage. In terms of getting data set, three types of the chopped lightning impulse voltages with different chopping times are considered and MRA is applied to these data as different case studies. Hence, some characteristic properties are extracted from the impulse waveforms at some special frequency values. In this sense, frequency component of 33 MHz is found with the maximum peak value for each case before the chopping time and their appearing times for three cases are determined using the time-frequency analysis. Hence the difference between the chopping time and occurring time of the maximum peak values at 33 MHz is calculated easily. Also, some physical interpretations of the frequency component of 33 MHz are defined through the circuit parameters of the measurement system. In usual application, the MRA can be presented as a powerful technique to extract the noise effects, which come from different sources, in the high voltage measurements.