DC Arc Resistance Rise by PMMA Cylinder Ablation with Arc Shrinking in Silica Sand Filling Space

Abstract

Concerning DC arc quenching phenomenon in silica sand filling space, we have proposed a new method for raising an arc column resistance (r col ) by use of polymer-material arrangement. This paper reveals physical factors for r col rise on the bases of experimental results using the following cylinders made of: (i) Quartz (SiO 2 ) and (ii) PMMA ((C 5 H 8 O 2 ) n ) with various inner diameters φ. For φ = 2 mm case, r col measured for a PMMA cylinder arrangement indicated higher r col at low current region, while almost same r col around current peak. For φ = 3 mm case, r col for the PMMA cylinder was lower than r col for the quartz case at high current region, while almost comparable between these conditions at low current region. For φ = 5 mm case, r col were almost same during the arc quenching process. To discuss the effect of the r col rise, the followings were also performed: (i) observation of cylinders after arc quenching and (ii) calculation of the electron density of SiO 2 /Cu or PMMA/SiO 2 mixture vapors. It is concluded that, at high current region, r col can increase due to the shrinking of the arc conductive diameter caused by the cylinder hole and the silica sand filled inside the cylinder hole. On the other hand, the admixing of the PMMA ablation vapor increases r col at low current region in the present experiment.

DC Arc Quenching Using Ablation of Polymer Narrow‐Section Arranged around Fuse Element

“…Therefore, it is necessary to develop new DC arc quenching medium for further rise in $$$ {r}_{\mathrm{arc}} $$$. In addition, we also found an arrangement of polymer material with the silica‐sand successfully increases $$$ {r}_{\mathrm{arc}} $$$ [9–11]. This rise in $$$ {r}_{\mathrm{arc}} $$$ can be interpreted based on improvement of $$$ \rho $$$ due to the polymer vapor admixing into the Cu/SiO 2 vapor mixture.…”

A mixture of Si3N4 powder and SiO2 sand as a novel DC arc quenching medium for improvement of the current-limiting performance of a model electric fuse

“…The formed vapor is admixed into the arc. The role of the arc quenching medium in the gas phase is to increase r arc to reduce the fault current, as [15,16,18,22,23] Ceramic 1973 (melting) 10 14 12.0-30.0 3.90 ZrO 2 [15,16,18,24] Ceramic 2954 (melting) 10 12 1.7-3.0 5.68 AlN [15,16,18,25,26] Ceramic 2500 (melting) 10 13 3.0-180 3.26 Si 3 N 4 [15,16,18,[26][27][28] Ceramic 2173 (melting) 10 12 10.0-100.0 3.11 depicted in figure 1. To increase r arc , an increase in the electrical resistivity ρ R of the arc, shrinkage of an arc diameter d arc , or arc length l arc elongation are necessary.…”

“…The authors group have studied a novel arc quenching medium which has higher arc quenching performance compared to flattery SiO 2 sand. For example, we successfully found that an additive of the polymer material with the SiO 2 sand increases r arc during the arc quenching process [11][12][13][14]. However, this method not only has advantages such as r arc increasing, but also the disadvantage of the decaying of R ins during the post-arc interruption process.…”

Direct current arc quenching performance of a model electric fuse equipped with SiO2 sand and additive silicone resin as an arc quenching medium: the effect of a vaporized silicone decomposition mixture on transient arc resistance

“…A re-solidified byproduct is known to form between electrodes during the arc quenching process in the filling SiO 2 sand. The formed byproduct is called 'fulgurite' [1,22,25]. In this experiment, the fulgurite produced between the electrodes in the model electric fuse was observed after the fuse operation to determine the fulgurite aspect for each condition.…”

“…The SiO 2 sand used as an arc quenching medium in the electric fuse has contributed to a rise in the transient arc column resistance r col to reduce the DC, and has eventually achieved a shorter arc quenching time for performing breaking of the DC. However, a further increase in the breaking ability of the electric fuse is expected in industrial fields, especially in DC distribution used in recent electric vehicles [22].…”