Effect of Step Response Measurement Arrangement on the Correction of Ultrahigh-Voltage Lightning Impulse Dividers

Ultrahigh-voltage (UHV) lightning impulse voltage dividers normally have limited bandwidth, which leads to deformation of the measured impulse waveform. The step response of the dividers can be used to correct the measured waveforms by deconvolution, reducing errors in the impulse parameters. The circuit arrangement for measuring the step response, however, may influence the measured step response. In this paper, two circuit arrangements for step response measurement were used to investigate the effect of different step responses on the corrected impulses. The lightning impulses, measured using two UHV dividers, were corrected and the errors in the impulse parameters before and after correction were determined. The results show that, although external circuit arrangements may cause significant differences in the measured step response parameters, accurate correction can still be made for the impulse voltage parameters measured with the dividers. The results also show the partial response time and experimental response time of a UHV divider's step response may not necessarily be related to the errors of parameter of the measured impulses.