Experimental validation of MOA simulation models for energy absorption estimation under different impulse currents

Excess energy absorption is an important reason of metal oxide arresters (MOA) failure. Theoretical prediction of MOA failure probability requires the accurate computation of energy absorption in MOA. Several models with good properties in predicting the peak residual voltage have been proposed for the simulation of the dynamic frequency-dependent behavior of MOA, but the performance of these models in estimating the energy absorption is not thoroughly investigated. In this paper, the accuracy of the non-linear resistance model and frequency-dependent models, including the IEEE model, Pinceti-Gianettoni model and Fernandez-Diaz model, in estimating the residual voltage and energy absorption under different impulse currents is investigated experimentally. The energy absorption of MOA under lightning current of 8/20 μs, switching surge current of 30/60 μs, and 1 μs steep current were simulated with different models and compared with the experimentally measured values under corresponding waveform currents. The results show that the frequency-dependent models are accurate in the evaluation of peak residual voltage, but not suitable for the simulation of energy absorption, with a relative error up to 60%, under steep impulse current. The non-linear resistance model shows its poor performance both on peak residual voltage and energy absorption estimation under steep impulse currents. The work of this paper shows that an improved model is necessary for simultaneous accurate prediction of peak residual voltage and energy absorption of MOA under steep impulse currents.