Extension of two return stroke models to consider the influence of elevated strike objects on the lightning return stroke current and the radiated electromagnetic field: comparison with experimental results

The presence of an elevated strike object markedly affects both the measured lightning return stroke current and the radiated electromagnetic fields. The MTL and the TCS lightning return stroke models have been extended to take into account the presence of elevated strike objects. In this paper, we compare theoretical results obtained using these two models with a set of simultaneously recorded data consisting of the current measured at the top of the Peissenberg tower and the associated electric and magnetic fields at about 200 m. It is shown that both the extended MTL and TCS models are able to reproduce with a reasonably good accuracy the magnitude and waveshapes of the electric and magnetic fields. However, the computed field peak derivatives are found to be much higher than the measured values. Possible reasons for this discrepancy are discussed in the paper