Low-voltage lightning arrester with built-in disconnector

Abstract

The invention discloses a low-voltage lightning arrester with a built-in disconnector, and belongs to the field of lightning arresters. A built-in hot melting separation component is arranged in the low-voltage lightning arrester, a low-temperature hot melting mode and a quick separation structure are adopted, heat generated by a valve plate / a resistance plate when the low-voltage lightning arrester fails is fully utilized to melt a hot melting medium in a working rated voltage range lower than 1kV, initiating an action of a pressure storage spring, and further achieving a function of an automatic hot melting type separation of a fault lightning arrester from the system on the low-voltage lightning arrester so as to prevent a further expansion of accidents. On the other hand, an obvious visibility mark can be given to the low-voltage lightning arrester which exits from the fault so that maintenance personnel can find fault points in time for maintenance and replacement. When the resistance plate in the low-voltage lightning arrester is about to thermally collapse, and short-circuit current is about to generate a front action, a damaged lightning arrester exits the system, and accidents caused by the short-circuit current are avoided. The low-voltage lightning arrester with the built-in disconnector can be widely applied to the fields of design, manufacture, operation, maintenance and the like of the low-voltage lightning arrester with a working voltage from 1kV to below 0.5kV.

Description

technical field [0001] The invention belongs to the field of lightning arresters, in particular to a lightning arrester used for overvoltage protection of a low-voltage power system. Background technique [0002] Surge arrester is an electrical device used to protect electrical equipment from transient overvoltage (lightning strike, operation, steep wave) and quickly cut off power frequency continuous current. It is usually connected in parallel with the protected line or equipment. [0003] Its internal main components are non-linear resistors (such as zinc oxide resistors), which are in a high-resistance state under normal power frequency voltage due to their good non-linearity, and the arrester will not operate. When the overvoltage occurs, the action resistance sheet of the arrester is turned on, and the overvoltage shock current absorbs part of the energy through the resistance sheet and then leaks into the ground, thereby reducing the amplitude of the overvoltage, redu...

AI Technical Summary

Problems solved by technology

[0014] Existing external hot-melt disconnectors or thermal-explosive disconnectors are only suitable for high and medium voltage systems, and cannot be applied to low voltage systems below 1kV and 0.5kV

The reason is that the rated voltage / operating voltage of the arrester in the low-voltage system is low, the air gap between the two electrodes cannot be broken down, and the arc cannot be generated in the thermal explosion disconnector, resulting in the thermal explosion disconnector being unable to pass through the detonation heat. Explosive components to achieve the purpose of "disconnecting" the ground lead

However, because the heat-melt disconnector is used externally, the heat generated by the fault current cannot be transmitted to the disconnector, so the disconnector cannot operate

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