CN2313290Y - High-voltage current-limited thermal element for protecting transformer - Google Patents

Abstract

The utility model relates to a high-voltage current-limited thermal element for protecting a transformer, which comprises a fusion tube which is filled with quartzite, both ends of the fusion tube are provided with inner caps; a larger and a smaller pillars are arranged between two inner caps, and variable load fuse elements are uniformly wound around pillars in equal intervals; a striker which is arranged between the inner cap and an outer cap can be powder type or spring type, and the rated breaking capacity is 50 kA. The utility model has the advantages of time-current stability (error only + /-10 %), obvious current limiting, low temperature rise, low power consumption, etc.

Description

The tranformer protection high-voltage and current-limitation fuse

The utility model belongs to high voltage protection electrical equipment, can be widely used in power transmission and transformation, box-type substation, fields such as city ring network power supply.

The indoor tranformer protection of 12KV that China produces is at present only accomplished 125A with the current limiting fuse maximum rated current.Along with China's development of electric power industry, the capacity of power equipment is increasing, presses for jumbo high-voltage and current-limitation fuse (10KV/160A～200A) protect.At present can only be from foreign procurement.But external product not only price is expensive, and some technical indicator has surpassed IEC282-1 and GB763 standard-required.Big as: temperature rise, power loss.

The purpose of this utility model is to overcome the shortcoming of above-mentioned prior art; develop a kind of 10KV/125A～200A tranformer protection high-voltage and current-limitation fuse; its specified breaking capacity is 50KA, has characteristics such as time one current characteristics is stablized (error only ± 10%), current limiting characteristic are remarkable, temperature rise is low (meeting IEC282-1 and GB763 standard), power loss is little.

The utility model is applicable to indoor interchange 50HZ, rated voltage 10KV, the electric power system of maximum operating voltage 12KV, rated current is from three kinds of specifications of 125A～200A, and high-voltage and current-limitation fuse production line and advanced person's the technology assembling means and the detection means of precision that can utilize my company to introduce, can guarantee that constant product quality refers to produce, satisfy domesticly that international two big markets are to the demand of this product.

Fig. 1 is a structure principle chart of the present utility model.

Fig. 2 is a melt structure schematic diagram of the present utility model.

Fig. 3 is the structure principle chart of gunpowder formula striker.

Fig. 4 is the structure principle chart of spring striker.

Referring to Fig. 1, the utility model is by 1 fusion tube, 2 big pillars, 3 little pillars, 4 melts, 5 quartz Sand, 6 interior caps, 7 liners, 8 rams (gunpowder formula or spring), 9 outer caps, the compositions such as 10 tungsten filaments, Its assembly relation is: the melt 4 that the pure silver belt punching out is become variable cross-section respectively equidistantly equably around On on the big or small porcelain pillar 2,3, and at melt 4 with low-melting alloy, be used for producing " M " effect, to improve the interrupting performance of low overload fault electric current, reduce fuse temperature rise and Power attenuation. The big pillar 1 that point welds is put in the fusion tube 1 into the ramuscule post 3 that again point is welded Put in the big pillar 2. Large and small pillar 2,3 two ends with the interior cap pricker at fusion tube 1 two ends Welded together. The ram 8 that will install again is installed between the inside and outside cap 6,9, ram 8 Lead-in wire be connected on the connector of cap 6 in the other end. Outer cap 9 depressed with interior cap 6 formed Be full of cooperation, at last highly purified quartz sand 5 put in the fusion tube by certain grain mixture ratio, enrich After, the outer cap 9 of the other end is depressed. All parts are by welding, compression, filling, mistake Be full of to cooperate and form integral body.

Referring to Fig. 2, the length L of melt 4=610 millimeter, width b=2.54 millimeter, narrow neck The b1=0.762 millimeter, radius r=0.25 millimeter, angle [alpha]=60 °, step pitch L1=9 millimeter.

Referring to Fig. 3, gunpowder formula striker is by 11 tungsten filaments, 12 epoxy resin, 13 stoppers, 14 gunpowder, 15 small caps, 16 guides, 17 strikers, compositions such as 18 limited parts.Its assembly relation is: gunpowder 14 is put into striker 17, tungsten filament 11 passes stopper 13 and is connected as lead-in wire with small cap 15 on the striker 17 by gunpowder 14, with stopper 13 gunpowder of striker 17 is clogged and to put into guide 16, with stopper 13 and 12 encapsulation of guide 16 usefulness epoxy resin, just consist of gunpowder formula striker again.

Referring to Fig. 4, the spring striker is by 19 braces, and 20 go between, 21 pads, 22 guides, 23 indication caps, 24 springs, 25 hooks, 26 linings, 27 packing rings, compositions such as 28 lock washers, its assembly relation is: hook 25 is placed on the spring 24, and lead-in wire 20 is from hook 25, spring 24, and pad 21 centers are passed.One of lead-in wire 20 is stuck between pad 21, the guide 22.When spring 24 compressions are put in place, take out tight other end lead-in wire, it is wrapped on the brace 19, will indicate cap 23 and lining 26 to put into guide 22 at last, guide 22 is clamped, make lining 26 fixing, just consist of the spring striker with anchor clamps.

Operation principle of the present utility model seals in fuse in the circuit of protected electrical equipment; when overload or short trouble take place in circuit; because the thermal effect of electric current; make the melt of fuse melt rapidly; vaporization; gap breakdown takes place subsequently; arcing and by the quartz sand extinguish arcs; divide deenergizing; simultaneously arc voltage be added in striker and the lead-in wire that is attached thereto between; enough big electric current is passed through, and gunpowder is lighted in the tungsten filament heating, produces blast; promote the striker tip and pass (or the lead-in wire fusing of the outer cap of fuse rapidly; the spring energy stored is vowed rapidly puts) provide indication, and, realize that three link with the trip gear of 2～4 joules the direct pull switch of energy; thereby can prevent the phase-deficient operation of circuit, reach the purpose of protection electrical equipment.

Because this high-voltage and current-limitation fuse has the breaking capacity height, operate time is fast, current limiting characteristic good, can before short circuit current no show peak value, just circuit be cut off rapidly, thereby the numerical value of limiting short-circuit current, reduction will be shown moving, the thermal stability of electric equipment in the electrical network, economical with materials and investment greatly has good social benefit and economic benefit.Western developed country mainly adopts the combined electrical apparatus of this high-voltage and current-limitation fuse+on-load switch to substitute and costs an arm and a leg, keeps in repair complicated circuit breaker abroad.In China; development along with urban network restructuring and power construction; to need increasing ring network power supply unit (ring main unit) and box-type substation; and a large amount of costs just that adopt of ring main unit and box-type substation are low, the good high-voltage and current-limitation fuse of protection transformer characteristic; the combined electrical apparatus of forming by this high-voltage and current-limitation fuse+on-load switch; have protection level height, dependable performance, price is low, maintenance is simple, easy to use, become common recognition.Therefore, the utility model has vast potential for future development.

Claims (4)

1. tranformer protection high-voltage and current-limitation fuse; comprise a fusion tube 1; be filled with quartz sand 5 in the fusion tube; the two ends of fusion tube 1 dispose interior cap 6; feature of the present utility model is; dispose big pillar 2 and the ramuscule post 3 that size is nested between the cap 6 in two, large and small pillar 2,3 equal intervals evenly are wound with variable load face melt 4, dispose striker 8 between interior cap 6 and the outer cap 9.

2. fuse according to claim 1 is characterized in that, the length L of melt 4=610 millimeter, width b=2.54 millimeter, narrow neck b1=0.762 millimeter, radius r=0.25 millimeter, angle [alpha]=60 °, step pitch L1=9 millimeter.

3. fuse according to claim 1 is characterized in that, said striker 8 comprises a guide 16, is placed with gunpowder 14, one tungsten filaments 11 in the striker 17 and passes stopper 13 and be connected with small cap 15 on the striker 17 by gunpowder 14.

4. fuse according to claim 1, it is characterized in that, said striker 8 comprises a guide 22, dispose indication cap 23 by lining 26 in the guide 22, an end disposes hook 25 in the indication cap 23, the other end disposes brace 19, disposes spring 24 and lead-in wire 20 between hook 25 and the brace 19.

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