CN201349094Y

CN201349094Y - Open-close current induction device for grounding switch

Info

Publication number: CN201349094Y
Application number: CNU2009200667397U
Authority: CN
Inventors: 夏志峰; 施文耀
Original assignee: SHANGHAI HUA TONG SWITCHGEAR CO Ltd
Current assignee: SHANGHAI HUA TONG SWITCHGEAR CO Ltd
Priority date: 2009-01-12
Filing date: 2009-01-12
Publication date: 2009-11-18
Anticipated expiration: 2019-01-12

Abstract

The utility model relates to the technical field of grounding switches, in particular to an open-close current induction device for a grounding switch. The open-close current induction device is characterized in that a copper-tungsten alloy is welded as an arc contact terminal in the middle of the top part of a movable contact; two legs of a n-shaped bracket are fixed on the outer side of the upper part of a front baffle plate and a rear baffle plate respectively; an insulation hole sleeve of an arc striking rod is arranged in the middle of the top part of the bracket; the middle position of the arc striking rod is welded with a wiring board into a whole; the top end of the arc striking rod is positioned in the insulation hole sleeve in the middle of the top part of the bracket; the bottom end of the arc striking rod penetrates an insulation guiding sleeve arranged between an conductive board and the arc striking rod, and positioned in the middle of static contacts on the left side and on the right side; a spring is sleeved outside the arc striking rod between the wiring board and the bracket; and two ends in flexible connection are connected on the wiring board and the conductive board respectively. Compared with the prior art, the open-close current induction device is additionally provided with an arc striking device formed by the arc striking rod and arc contact terminals made of copper-tungsten alloy, avoids the loss by burning during the divide-shut brake operation of the movable contact and the static contact, and prolongs the service life of the grounding switch.

Description

Earthed switch folding current sensing means

[technical field]

The utility model relates to the earthed switch technical field, is a kind of earthed switch folding current sensing means specifically.

[technical background]

Development along with power construction, electrical network is constantly enlarging, capacity is also in continuous increase, in order to take up an area of in the corridor of reducing transmission line, the parallel aerial high-voltage power transmission line in common-tower double-return road day by day increases, transformer station at this transmission line two ends, the high voltage ground switch that its inlet wire side and outlet side are used should have the ability of opening and closing induction current.And according to stipulating in GB1985-2004 " high-voltage alternating current isolating switch and the earthed switch " appendix C: its specified induced current effective value 80A of folding electromagnetic coupled, specified induced voltage effective value 2kV; Its specified induced current effective value 3A of folding Electrostatic Coupling, specified induced voltage effective value 12kV.So high voltage ground switch must have the reliable protection device to guarantee safe operation.

In with pylon double loop overhead transmission line, after a certain line outage and since it with adjacent alive circuit between produce electromagnetic induction and electrostatic induction, on the loop of power failure, will produce induced voltage and induced current, therefore belong to the earthed switch of these circuits, should be able to satisfy following service conditions:

One, when an end of dead line open circuit, when the earthed switch branch of the circuit other end, closing operation, earthed switch can cut-off and capacity current is closed in the pass, referring to static induced current schematic diagram in the accompanying drawing 3;

Two, when an end ground connection of dead line, when the earthed switch of the circuit other end divided closing operation, earthed switch can cut-off and inductance current is closed in the pass, referring to the em induced current schematic diagram of accompanying drawing 4.

And existing earthed switch, moving contact and fixed contact are closed or separate when divide-shut brake, and the electric arc that causes is easy to dynamic and static contact burning, and had a greatly reduced quality the useful life of earthed switch.

[summary of the invention]

The purpose of this utility model is in order to overcome the deficiencies in the prior art, set up the arc-initiating device of being made up of arc ignition bar, arcing contact etc. in earthed switch, having avoided the scaling loss of moving contact and fixed contact.

For achieving the above object, a kind of earthed switch folding current sensing means is provided, mainly comprise conductive plate, front apron, backboard, moving contact, fixed contact, after fixing respectively about described conductive plate, front apron, fixing fixed contact respectively before and after the conductive plate, moving contact contacts for closing a floodgate with fixed contact, it is characterized in that: the weldering of moving contact crown center is established a copper-tungsten layer as arcing contact, before two pin of " n " shape support of a metal are separately fixed at, the backboard upper outside, the support crown center is established the insulation borehole jack of an arc ignition bar, arc ignition bar medium position and terminal block are welded as a whole, the top of arc ignition bar places in the insulation borehole jack of support crown center, the bottom of arc ignition bar is passed insulation fairlead set between conductive plate and the arc ignition bar and is placed in the middle of the fixed contact of the right and left, the outer sheathed spring of arc ignition bar between terminal block and the support, arc ignition bar can be moved both vertically up and down, arc ignition bar is owing to limited by terminal block, lower limit rests on the fairlead, guarantee the distance between its bottom and moving arcing contact, the two ends that are flexible coupling are connected on terminal block and the conductive plate.

One side of the corresponding backboard of described moving contact is provided with the guide pad of insulation, and guide pad mainly has been two effects, and the one, play the contacting ignition arc that insulating effect has been avoided moving contact and backboard; The 2nd, play the striking that cushioning effect avoids the moving contact spring to be produced.

The zinc-plated copper litz wire braiding of the described employing conduction that is flexible coupling forms, and the main effect that is flexible coupling is that the electric current on the arc ignition bar is flowed to conductive plate by being flexible coupling of conduction.

Compared with prior art, the utility model has been set up the formed arc-initiating device of mainly being made by arc ignition bar and copper-tungsten of arcing contact, and scaling loss when having avoided moving contact and fixed contact divide-shut brake has prolonged useful life of earthed switch.

[description of drawings]

Fig. 1 is a structural representation of the present utility model.

Fig. 2 be the A at the following position of front apron shown in Figure 1 to partial schematic diagram, wherein a represents the distance between moving contact and the fixed contact, b represents the distance between arcing contact and the arc ignition bar.

Fig. 3 is about the static induced current schematic diagram with pylon double loop trolley wire in the utility model.

Fig. 4 is about the em induced current schematic diagram with pylon double loop trolley wire in the utility model.

Referring to Fig. 1 and Fig. 2,1 is support; 2 is spring; 3 is fairlead, adopts insulating material, guarantees the arc ignition bar lengthwise movement; 4 is backboard; 5 is arc ignition bar; 51 is terminal block; 6 is arcing contact; 7 is fixed contact, and three of bamboo raft shapes are on one side, and each fixes a row before and after the conductive plate; 8 is guide pad, adopts the insulation material; 9 is moving contact; 10 for being flexible coupling; 11 is conductive plate; 12 is front apron;

Referring to Fig. 3 and Fig. 4,13 is alive circuit; 14 are alive circuit not.

Appointment Fig. 1 is a Figure of abstract.

[embodiment]

Below the utility model is described in further detail, the utility model is still more clearly for the people of this professional skill field.

When earthed switch closes a floodgate, under the effect of motor drive mechanism, moving contact 9 rotates up 90 ° from horizontal direction, when making the guide pad 8 contact backboards 4 of the insulation on the moving contact 9, moving contact 9 changes ascending motion into from previous rotatablely moving, at this moment, since between the fixed contact 7 of moving contact 9 and both sides bamboo raft shape apart from a greater than the distance b between arcing contact 6 and the arc ignition bar 5, at first burning between arcing contact 6 and arc ignition bar 5 of the electric arc that induced current produced, along with the continuation of moving contact 9 is risen, arcing contact 6 contacts with arc ignition bar 5 earlier, and induced current just by being flexible coupling 10 on the arc ignition bar 5, flows to conductive plate 11, this moment arc extinction, because it is moving, the contact of the combined floodgate of fixed contact lags behind contacting of arcing contact 6 and arc ignition bar 5, has avoided moving, the scaling loss of fixed contact.

Similarly, during the earthed switch separating brake since dynamic and static contact separately prior to the separating of arc ignition bar 5 and arcing contact 6, and make the dynamic and static contact can be by scaling loss.

In addition, set fairlead 3 between conductive plate 11 and the arc ignition bar 5 in the device, not only played insulation guide effect to arc ignition bar 5, guaranteed that arc ignition bar 5 bottoms contact with the accurate of arcing contact 6, and the terminal block of establishing 51 is welded in arc ignition bar 5 middle parts, controlled the extreme lower position that arc ignition bar 5 falls, thereby guaranteed that arc ignition bar 5 tops are positioned at the borehole jack of the insulation of the set arc ignition bar of support 1 all the time, prevented the skew that arc ignition bar 5 rises, the spring 2 on terminal block 51 tops has then been controlled the resetting of decline of arc ignition bar 5.

This covering device is folding earthed switch induced current effectively, has avoided earthed switch dynamic/static contact scaling loss in closing branch, has guaranteed the safe operation of earthed switch when operating mode, has prolonged earthed switch useful life simultaneously.

Need to prove that earthed switch is when opening and closing induction current, because the operating voltage grade is higher, the electromagnetic coupled induced voltage is 2kV, the Electrostatic Coupling induced voltage is 12kV, so consider from the angle of safety operation, earthed switch links three and closes branch and operate appropriate to the occasion employing electric operating mechanism and carry out remote operation, and the electric operating mechanism case must have reliably, effective ground connection.

Claims

1, a kind of earthed switch folding current sensing means, mainly comprise conductive plate (11), front apron (12), backboard (4), moving contact (9), fixed contact (7), after fixing respectively about described conductive plate, front apron, fixing fixed contact (7) respectively before and after the conductive plate, moving contact contacts for closing a floodgate with fixed contact, it is characterized in that: the weldering of moving contact (9) crown center is established a copper-tungsten layer as arcing contact (6), before (1) two pin of " n " shape support is separately fixed at, the backboard upper outside, support (1) crown center is established the borehole jack of the insulation of an arc ignition bar, arc ignition bar (5) medium position and terminal block (51) are welded as a whole, the top of arc ignition bar (5) places in the borehole jack of insulation of support (1) crown center, fixed contact (7) centre that insulation fairlead (3) set between conductive plate (11) and the arc ignition bar (5) is placed on the right and left is passed in the bottom of arc ignition bar (5), the outer sheathed spring (2) of arc ignition bar between terminal block (51) and the support (1), make the arc ignition bar lengthwise movement, the two ends of be flexible coupling (10) are connected on terminal block (51) and the conductive plate (11).

2, a kind of earthed switch folding current sensing means as claimed in claim 1, it is characterized in that: a side of the corresponding backboard of described moving contact (9) (4) is provided with the guide pad (8) of insulation.

3, a kind of earthed switch folding current sensing means as claimed in claim 1 is characterized in that: described be flexible coupling (10) adopt zinc-plated copper litz wire braiding to form.