Three-position switch for transferring current by quickly disconnecting bus

Abstract

The invention discloses a three-position switch for transferring current by quickly disconnecting a bus, and the three-position switch is used for solving the problems in the prior art that a conducting rod in an inner cavity of a movable conductor can impact the bottom of the inner cavity of the movable conductor, thereby shortening the service life of a disconnecting conductor and the movable conductor and influencing the disconnecting speed, and a circular ring-shaped gap is formed between the solid conducting rod and a disconnecting spring seat, instantly ejected gas is in the shape of a circular ring and is easy to diverge, the ejected gas flow is weak, the speed of the gas is slow, and thus the disconnecting speed is influenced. The three-position switch is characterized in that a helical conductor with a simple structure and good rigidity is further arranged in the inner cavity of an isolation conductor, a buffer is arranged in the cavity of a movable conductor, a front exhaust hole is formed in an internal hollow channel of a hollow conducting rod, and an arched exhaust channel is formed by a gap between the side plane of a shock adsorbing seat of the buffer and the movable conductor. The three-position switch has the beneficial effects that the gas flow formed by compressed gas ejected from the inner cavity of the movable conductor is strong, the speed of the gas is high, the ejected gas flow is in favor of arc failure, and the mechanical life of the disconnecting conductor and the movable conductor are improved.

Description

technical field [0001] The invention belongs to the technical field of high-voltage power transmission and distribution, and in particular relates to a three-position switch for quickly breaking busbar transfer current in switch combination electrical equipment using clean and dry compressed air or nitrogen as an insulating medium. Background technique [0002] The three-position switch is an important electrical component on the switchgear, and the three-position switch capable of transferring the bus current is the core component of the double-bus switchgear. A three-position switch with the ability to break the transfer current of the busbar. It drives the insulating connecting rod to rotate through the three-position switching mechanism, and the insulating connecting rod drives the rack fixed on the moving conductor through the gear to perform linear reciprocating motion. When the moving conductor moves to different positions, the three states of circuit conduction, iso...

AI Technical Summary

Problems solved by technology

During the type test of the sample of this invention, it was found that when the conductive rod in the inner cavity of the movable conductor breaks the busbar to transfer the current, the energy released instantly by the compressed breaking spring will drive the conductive rod to hit the movable conductor. The bottom of the cavity, because the type test requires 100 times of opening and closing, in fact, after dozens of times of the type test, the bottom of the inner cavity of the movable conductor and the impact part of the conductive rod are deformed, this is because a high speed is required for breaking, and the opening The speed does not need to be too high at the end of the breaking stage. The existing technology only considers the high speed in the early stage, without a good deceleration device in the later stage, and only relies on mechanical impact to stop, which greatly reduces its service life and affects the breaking speed. In addition , because the conductive rod is solid, the gas in the inner cavity of the movable conductive rod is instantly ejected to form a compressed air blow, which plays the role of rapidly extinguishing the arc between the isolation fractures to break the transfer current of the bus bar. The gap between the rod and the breaking spring seat is ejected. The problem is that, first, because the gap between the solid conductive rod and the breaking spring seat is in the shape of a ring, the instantaneously ejected gas is in the form of a circle. Ring shape, easy to diverge; second, because the ring-shaped gap between the solid conductive rod and the breaking spring seat is small, the ejected airflow is weak and slow, which affects the breaking speed

Due to the existence of the above two problems, the arc extinguishment between the isolation fracture composed of the moving conductor and the isolation conductor is still relatively slow. The head, the contact finger spring inside the isolation conductor and the isolation and breaking conductor are seriously ablated, so there is a problem of poor safety; third, the frictional contact between the conductive rod and the isolation conductor contact spring, repeated use will cause Reduce the elasticity of the isolated conductor finger spring; it has a greater impact on the friction between the conductive rod and the isolated conductor finger spring, which in turn affects the synchronization of the three-phase three-position switch breaking the bus transfer current

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