Modeling and simulation of the current quenching behavior of a line lightning protection device

Abstract

We develop a consistent model for a line lightning protection device (LLPD) and demonstrate that it can explain the two modes of current quenching-impulse quenching and current zero quenching-observed in such devices. A dimensional analysis shows that impulse quenching can always be obtained if the power loss from the electric arcs is large enough as compared to U I f 0 , where U 0 is the grid voltage and I f is the maximum follow current after a lightning strike. We further show that the two modes of quenching can be reproduced in a full 3D arc simulation coupled to the appropriate circuit model, which allows us to analyze the power loss from the arc in greater detail. Because of the high temperature, the main mechanism of power loss is radiation which has to be correctly modeled in order to obtain physically meaningful results. The results will allow us to use numerical simulations to optimize the quenching ability to LLPDs in the future.

From the molten bridge rupture to the local thermal equilibrium arc: optical emission spectroscopy of electric arcs during contacts opening

“…The simulation of arc dynamics in switching devices usually assume LTE conditions [1][2][3]. Since switching events in arc-based devices usually take at least a few ms, the fact that LTE is reached in the bulk of the plasma already 0.04 ms after molten bridge rupture confirms that this assumption is reasonable.…”

“…The local thermal equilibrium (LTE) approximation is a common assumption made when modeling electric arcs in low-voltage switching devices using magnetohydrodynamics methods [1][2][3]. While this approximation is usually verified in the bulk of the plasma, it is known to fail at providing a correct description of near-electrodes phenomena [4].…”

A Review of Progress Towards Simulation of Arc Quenching in Lightning Protection Devices Based on Multi Chamber Systems

“…It is possible then to precompute all thermodynamic properties and store in the form of lookup tables as described in ( [5][6][7]). For simplicity, electrode erosion and ablation of wall material were neglected, making it possible to consider pure air arc discharge.…”

“…The most important effect is that high frequencies are strongly absorbed, whereas low frequencies are not so it was decided to use a simple two-band model. The first frequency band has a wavelength starting from zero up to λ = 120 nm and an absorption coefficient of α = 2000 m −1 , the second band starts from λ = 120 nm up to λ = 1 mm with α = 50 m −1 [7].…”

“…In order to simulate arc quenching (1)-(3) were coupled with circuit equations [7]. The circuit is depicted in Fig.…”