EXPERIMENTAL AND SIMULATION STUDIES ON THE VOLTAGE DROP OF ARC IN LOW-VOLTAGE CIRCUIT BREAKER

International audienceIn low voltage circuit breaker (LVCB) apparatus, a current limitation is performed by increasing the arc voltage. This increase is mainly realized in the splitters plates of the arc chamber by additional drop voltages due to anode and cathode sheaths regions. The consideration of the voltage drops near-electrodes regions is so one of the most important mechanism to improve the description of the arc behavior in LVCB. In this paper, the arc voltage evolution has been studied by experimental and simulation by considering a simple geometry constituted by two rails runner with one or two splitters plates. One magneto hydrodynamic model in three dimensions (3D) was developed to simulate the arc motion and the arc splitting process. In order to compare with the model results, experimental tests have been carried out

Numerical analysis of switching performance evaluators in low-voltage switching devices

An arc modelling is a valuable and useful tool to evaluate the switching performance of low-voltage switching devices (LVSDs) during breaking operation before testing real products. Moreover, it helps improve interruption capability of LVSDs and optimize them. This paper focuses on the numerical simulation of the arc behavior in AC devices before zero current and prediction of the re-ignition after current zero based on the simulated arc voltage. The 3-D arc modelling is based on the conventional magnetohydrodynamics theory and it considers the motion of a contact, arc root, radiation and air properties which vary with the temperature and pressure

Numerical Analysis of low voltage Arc Motion Process at Various Frequencies

A three-dimensional (3D) magneto-hydro-dynamic (MHD) model of air arc plasma is built to investigate the frequency effects on the arc motion process with different number of splitter plates. Based on this model, the arc voltage and current density are obtained. The arc motion time is normalized with the frequency and compared at different numbers of splitter plate. The result shows that the normalized time and the arc voltage peak increase with increases of the number of splitter plate

3D Analysis of Low-Voltage Gas-Filled DC Switch Using Simplified Arc Model

Electro-magnetic simulations have been used for the visualization of distribution of Lorentz force acting on a DC switching arc in low-voltage contactor. A simplified plasma model (black-box model) was applied for the description of arc conductivity. Arc geometry was gained from the high-speed camera images. Influence of arc position, arc current and of external magnetic field has been studied. Results have been compared with optical observations of the arc dynamics

Inverse Problem Solution and Regularization Parameter Selection for Current Distribution Reconstruction in Switching Arcs by Inverting Magnetic Fields

Current density distribution in electric arcs inside low voltage circuit breakers is a crucial parameter for us to understand the complex physical behavior during the arcing process. In this paper, we investigate the inverse problem of reconstructing the current density distribution in arcs by inverting the magnetic fields. A simplified 2D arc chamber is considered. The aim of this paper is the computational side of the regularization method, regularization parameter selection strategies, and the estimation of systematic error. To address the ill-posedness of the inverse problem, Tikhonov regularization is analyzed, with the regularization parameter chosen by Morozov’s discrepancy principle, the L-curve, the generalized cross-validation, and the quasi-optimality criteria. The provided range of regularization parameter selection strategies is much wider than in the previous works. Effects of several features on the performance of these criteria have been investigated, including the signal-to-noise ratio, dimension of measurement space, and the measurement distance. The numerical simulations show that the generalized cross-validation and quasi-optimality criteria provide a more satisfactory performance on the robustness and accuracy. Moreover, an optimal measurement distance can be expected when using a planner sensor array to perform magnetic measurements