WANG Feiming, ZHAO Yisong, ZHANG Bo, et al. Numerical Calculation and Analysis of the Breaking Process of 10 kV Jet Fuse[J]. High voltage apparatus, 2024, 60(11): 191-200.
DOI:
WANG Feiming, ZHAO Yisong, ZHANG Bo, et al. Numerical Calculation and Analysis of the Breaking Process of 10 kV Jet Fuse[J]. High voltage apparatus, 2024, 60(11): 191-200. DOI: 10.13296/j.1001-1609.hva.2024.11.023.
Numerical Calculation and Analysis of the Breaking Process of 10 kV Jet Fuse
High-voltage jet fuse is a kind of protection device which is used widely in distribution network of power system
and the study of its arcing characteristics is of great significance for the reliable operation of the fuse. In this paper
the 10 kV jet fuse is taken as the research object. First
the electric field intensity in the fuse is calculated by the three-dimensional finite element simulation
and the curve of the maximum electric field
E
max
with the clearance is obtained. A two-dimensional dynamic arc mathematical model considering ablation is set up and calculated. The arc characteristics of the fuse at
the breaking currents of 12.5 kA
2.5 kA are calculated
the influence of two types of currents and arc shortening rods with different lengths on the ablation quality
gas pressure distribution and velocity distribution of the inner wall of the arc extinguishing tube of the fuse is compared and analyzed. The medium recovery curve of the gas after breaking the short circuit current by the fuse is obtained on the basis of the streamer theory and in combination with the calculation results of the electric field and the gas flow field. The calculation results show that in the electric field calculation
the maximum electric field
E
max
is at the top of the flexible copper stranded wire
which decreases with the increase of the clearance
and the influence of the arc shortening rod on the electric field is small. The ablation quality
overall gas pressure
axial velocity and temperature in the fuse at the breaking condition at 12.5 kA are higher than those at 2.5 kA. In case of same length of the arc shortening rod
the higher the breaking current is
the stronger the medium recovery ability is. When the arc shortening rod is within the range of 105~155 mm
the increase of the length of the arc shortening rod can enhance the breaking capacity of high current
but can reduce the breaking capacity of small current. The research results can provide a theoretical basis for the arc extinguishing characteristics analysis of the fuse.