Comparative study of ZnO surge arrester models by means of lightning overvoltage simulation

This paper presents a comparative study of electric models for ZnO surge arresters. The Conventional model, the IEEE model and a novel wide-range model were compared. To that end, lightning impulses with 10 kA amplitudes were simulated using both a standard waveform (8/20 μs) and steep front (1/2 μs). The simulated system consisted of a 500-kV overhead line connected to a transformer, in the absence and then in the presence of a surge arrester. The ATP software was employed to perform simulations of electromagnetic transients in time domain. Differences greater than 10% were obtained for the overvoltages calculated using the three models. Thus, it is manifest the need for a progressive effort in the study and evaluation of different surge arrester models, in order to increase reliability of transient studies.