Frequency analysis of the typical impulse voltage and current waveshapes of test generators

Abstract

Frequency analysis of the impulse waveshapes of generators which are commonly used for testing of the equipment in high-voltage engineering is presented in this paper. Some of the typical impulse waveshapes, such as 1.2/50 ?s/?s, 10/350 ?s/?s, 10/700 ?s/?s, 10/1000 ?s/?s, and 250/2500 ?s/?s, are approximated by the Double-exponential function (DEXP) and by the terms of Multi-peaked analytically extended function (MP-AEF). Experimental set ups for impulse signal generation are based on the desired outputs as given in the IEC 60060-1 Standard. Dumped oscillations are characteristic of the standardized 8/20 ?s/?s waveshape. The positive part of the normalized Sinc function with dumped oscillations is also approximated by MP-AEF terms. The corresponding frequency spectra of these aperiodic signals are obtained analytically by using Piecewise Fourier transform (PWFT). This paper presents the procedure to obtain Fourier transforms of the functions with multiple and sharp peaks typical for the impulse current and voltage test generators? waveshapes.