Abstract
The occurrence of a partial arc can affect insulation properties of the insulator by different types of flashover. In order to investigate the influence of a partial arc on electric field distribution along the catenary insulator string, a three-dimensional model of the cap-pin insulator string with partial arc was established in this paper. The electric field distribution along the insulator string when the arc extended on the insulator surface and bridged sheds was investigated based on the electric field analysis using the finite element method. The results showed that the occurrence of a partial arc caused obvious distortion of the electric field, which was a two-dimensional axis symmetrical field before arcing to a three-dimensional field. In the case of arc extension, the sudden rise of field intensity was mostly at the rib and the shed edge, which had the local maximum field intensity. The rib and the shed edge played a certain hindrance role in the extension of the arc. The main reason for promoting the development of the arc can be attributed to thermal ionization. In the case of arc bridge sheds, the highest field intensity appeared at the edge of the last bridged shed. As the number of sheds arc-bridged increased, the maximum field intensity also increased. As the arc length increased, the electric field intensity of the arc head also increased, which resulted in an accelerated arc development. The main factor to promote the development of the arc can be attributed to electrical breakdown. The measures to hinder the rapid development of partial arcs were proposed.
Highlights
As a special high-voltage transmission line, the electrified railway catenary is installed above rails and transmits electric energy to electric locomotives or motor train units by making contact with pantographs [1]
The cap-pin insulator string of an electrified railway catenary is shown in Figure 2, and is
The main reason for promoting the development of the arc can be attributed to thermal ionization
Summary
As a special high-voltage transmission line, the electrified railway catenary is installed above rails and transmits electric energy to electric locomotives or motor train units by making contact with pantographs [1]. The influences of the operating environment on the electric field droppings [10], surface contamination layer dry zone [12], separated globules [13], and sosurface on It distribution of insulators were studied, such[11], as icing [8], sand dust [9], bird droppings [10], was further clarified thatdry the zone operating environment plays [13], an important role in the safe operation of contamination layer [11],. Sima Wenxia calculated the relationship between the between the development of partial arc and the electric field distribution of single cap-pin insulators. Development of partial arc and the electric field distribution of single cap-pin insulators. The finite element method was used to build a simulation model of the insulator string in the software
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have