Method for endowing low-voltage arrester with automatic separation function

Abstract

The invention relates to a method for endowing a low-voltage arrester with an automatic separation function and belongs to the field of arresters. A built-in hot melting separation component is arranged on a lower end face of a lower polar plate of a low-voltage arrester main body; the built-in hot melting separation component comprises a ground lead metal core wire and a low-temperature hot melting medium layer arranged between the front end of the metal core wire and the lower end face of the lower polar plate; a first spring is sleeved between the front end of the metal core wire of the ground lead and the lower end face of the lower polar plate; when the low-voltage arrester is in internal fault, the temperatures of upper and lower polar plates rise; after the temperature of the lowerpolar plate exceeds the hot melting temperature point of the low-temperature hot melting medium layer, the metal core wire of the ground lead falls off from the lower end face of the lower polar plateunder the action of prestored elasticity of the first spring and is disconnected from the lower polar plate of the low-voltage arrester, and the low-voltage arrester in fault can stop running, so that the automatic separation function can be realized. The method can be widely applied to the fields of design, manufacturing or operation maintenance of the low-voltage arrester under the working voltage below 1kV-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

Images