Analysis of Metal Oxide Surge Arrester’s Dynamic Performance for Lightning Protection

Abstract

One of the key factors that hinder satisfactory performance of metal oxide surge arresters (MOSAs) against the damaging effects of overvoltage transients is accurate representation of their dynamic behaviour. Therefore, this study analysed dynamic characteristics of MOSA using IEEE and Fernández-Díaz equivalent circuits with ABB MWK surge arrester used as a test case. The impulse current input to the equivalent circuits was modelled using Gaussian equation. Simulations were done and residual voltage and quenching time of the models for impulse currents inputs of 1, 5, 10 and 20 kA respectively were determined. The obtained residual voltages were compared with the manufacturer’s standard in the test arrester datasheet. Residual voltages of 115, 128, 137 and 157 kV respectively were obtained for 1, 5, 10 and 20 kA impulse currents impressed on both IEEE and Fernández-Díaz models. While 115 and 128 kV residual voltages respectively tallied with the manufacturer’s standard for 1 and 5 kA impulse currents, 137 and 157 kV residual voltages were found to exceed the standard for 10 and 20 kA impulse currents respectively. The quenching time for the voltage surge resulting from 1, 5, 10 and 20 kA currents injection on both adopted models were 0.2, 0.22, 0.225 and 0.23 ms respectively with no damping observed in the voltage response of Fernández-Díaz model unlike in the IEEE model. The study indicated that Fernández-Díaz model produced a better MOSA dynamic response for the study.