High-speed video observations on fork lightning events in Malaysia

Abstract

Malaysia is one of the countries with the highest lightning strikes incidence in the world. Yet, Malaysians are still taking a proper lightning protection indifferent manner. This might be due to lack of knowledge on lightning characteristics in Malaysia. Therefore, this study presents an unusual lightning phenomenon with multiple grounding points that might cause a disastrous event, called fork lightning. Between November and December 2018, there were three different patterns of fork lightning mechanism successfully recorded by using high speed camera with 2800 frame per second. Temporal analysis of the lightning progress had been done on the samples based only on the camera records which then played back by using Wondershare Filmora video editor. These three samples of fork lightning images were acquired among 37 lightning events recorded in this study. The first sample of fork lightning fully established the forked branch 0.35 ms before the return stroke occurred. On the contrary, second fork lightning established its forked branch 0.35 ms after the return stroke. Both forked branches for third sample simultaneously fully established with the return stroke event. Obviously, these events had striking the ground in up to ten milliseconds of time duration. Thus, there is always a possibility that they might cause serious damage and should not be neglected in designing a lightning protection system.

Analysis of the performance of grounding grids buried in heterogeneous soil under impulse current

“…The act of this system is changed under impulse current [2]. This makes the behaviour of grounding systems an objective for different investigations, and which have been improved by several simulations and practical tests cited as follow: Ramlee et al [3] have studied the use of multiple grounding points on the lightning phenomenon. Azmi et al [4] have improved the grounding system impedance by adding enhancement materials in the surrounding of the studied electrode.…”