摘要:The objects of the research are: full and simplified dynamic models of surge arresters, as well as the model of surge arrester in the form of a nonlinear resistor. For the simulation of the voltage-current characteristics, in the latter case the approximation was used, describing by one expression both switching and lightning surge domain. At the present time, the traditional approach is applied for the study of surge arrester models. The surge arrester model is connected in series with a current source of a given waveform and amplitude. Then, the residual voltage is computed on the surge arrester model. The simulation results are compared with the corresponding passport values and a conclusion is made about the applicability of this model.In practice, as a result of lightning activity, surge arresters are exposed to impulse voltage waves. The use of voltage impulses in comparing the models of metal-oxide surge arresters has not been studied sufficiently yet.Analysis of different surge arrester models subjected to the lightning current impulses was carried out. The residual voltage, which arises in this case on the surge arresters, was computed. The results obtained with a nonlinear resistor do not differ from the results obtained with the full model by more than 5.74%, and from the results obtained with the simplified model by more than 5.67%. Analysis of the same surge arrester models subjected to the lightning voltage impulses was carried out. The residual voltage, which arises in this case on the surge arresters, was computed. The results obtained with a nonlinear resistor do not differ from the results obtained with the full model by more than 9.41%, and from the results obtained with the simplified model by more than 7.85%.When making final choice of a particular surge arrester model, it is preferable, because of the need for a certain safety factor, to choose model which gives largest residual voltage values when the voltage impulses are applied. It has also been established that even when modeling a surge arrester in the form of a nonlinear resistor, but taking into account the approximation of its voltage-current characteristic by one expression, the results do not exceed the limits of engineering accuracy.
关键词:model of surge arrester;current impulse;voltage impulse;voltage-current characteristic