Effect of Lightning Impulse Polarity and Time Constants on Arc Electric Energy Density in Multi Chamber Arc‐Extinguishing Arrester

ABSTRACT

Lightning strikes on overhead lines cause transient over‐voltages, which can damage the insulation systems and provide the flashover and also service interruption. The protection systems are designed to safeguard electrical equipment from the destructive effects of lightning strikes. So, understanding the mechanism of lightning and its effects on transmission infrastructure is essential for utilising proper protection strategies. Multi chamber arc‐extinguishing arresters (MCAAs) are widely used to protect transmission lines from lightning due to their reliable arc‐quenching performance. In this paper an arc quenching process in this arrester after lightning breakdown is analysed. For this purpose, the arc behaviour of MCAA is investigated, considering the effect of lightning specification changes. So, the arc electric energy density (AEED) has been analysed by considering its decisive role in the process of electric arc discharge. In the present work, an MCAA was set up using COMSOL multiphysics software. The simulation results show that the arc discharge process is faster than other situations, when the lightning surge has shorter rise and fall times with positive polarity. Also, in this state, the arrester has a better performance due to faster arc extinction compared to the standard lightning current waveform (8/20 µs).