Validation of ZnO surge arresters model for overvoltage studies

This paper presents an improvement of the procedure to determine the parameters of the simplified model for metal-oxide surge arresters, derived from the IEEE standard model. The main innovation introduced by the paper lays in the possibility to define an approximate dynamic model even if data about residual voltages for steep current pulse are not defined in the manufacturer´s data sheets. This model has a wide rangeability and its effectiveness is good for both medium- and high-voltage arresters. The effectiveness of the model was tested for several arresters of different manufacturers. The residual voltages reported in the datasheets and obtained by the manufacturers through a discharge test are compared with the simulations performed with Matlab. The possibility of defining a dynamic model for surge arresters even with missing data makes the proposed model a useful tool for insulation coordination studies involving steep front transients.