Heat explosion type releasing device for lightning arrester

Abstract

The invention discloses a thermal explosion type disconnector of an arrester, which comprises an upper electrode and a lower electrode arranged opposite to each other, a resistor and a thermal explosion tube; a discharge gap is formed between the upper electrode and the lower electrode; the discharge gap is firstly connected in parallel with the resistor, and then connected in series with the thermal explosion tube; the resistor comprises an insulation core with thickness, and a layer of resistor enamel membrane attached to the surface of the insulation core; the resistor enamel membrane extends in the thickness direction of the insulation core, and the two end parts of the resistor enamel membrane are electrically connected with the upper electrode and the lower electrode respectively; the resistor enamel membrane consists of countless series branches connected in parallel with each other; the removal of any series branch only can increase the resistance and reduce the power; local arc discharge every time cauterizes one of the series branches, thereby causing the pressure drop at the two ends of the resistor to be further increased, and helping the gap to discharge and the disconnector to move; and the insulation core is resistant to arc incandescence, thereby ensuring that the resistor R is not short-circuited. Therefore, when the arrester fails, that is, passes through an I drag, no miss trip occurs to the disconnector.

Description

technical field [0001] The invention relates to a disconnector of a lightning arrester, which is usually used in series with the lightning arrester. When the lightning arrester breaks down, it can act quickly to make the lightning arrester quit running. Background technique [0002] When the arrester fails, it is thermally destroyed, and it operates by using the heat energy of the power frequency current that increases when the arrester is destroyed. [0003] The general structure of the thermal explosion disconnector is: a discharge gap, an element R connected in parallel with the gap, and a thermal explosion tube is placed on the upper or lower end surface of the gap. When the arrester is running, the continuous power frequency current I C All pass through parallel element R. And when the current passing through the parallel resistor R increases, or the resistance value of R becomes larger, causing the voltage drop at both ends of the parallel resistor R to exceed the ga...

AI Technical Summary

Problems solved by technology

However, PTC is a volume resistance, and it is easy to produce a large resistance value deviation during manufacture.

Moreover, although volume resistance generally does not cause open circuit, under the high field strength of gap discharge, once it is broken down, an irrecoverable short circuit will be formed.

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