Characterization of Cable Effects on a Reference Lightning Impulse Voltage Divider

Effect of measurement cables on impulse voltage measurements has been widely ignored by the high voltage community. During the last years the cable length effects have been reported but the results have not been fully consistent. This paper will characterize cable effects on a resistive impulse voltage divider using three different test methods. Used methods are step response analysis using convolution, low-voltage analysis with an impulse calibrator, and high-voltage impulse analysis with an impulse generator. Results show that with reasonable cable lengths less than 25 meters, the time parameter errors increase almost linearly with the cable length. In addition, the results show that the applied methods are comparable ways to determine the overall performance of an impulse voltage measuring system, including the cable effect.