CN202796412U - Flexibility coil current transformer - Google Patents

Abstract

The utility model provides a flexibility coil current transformer which comprises that silicon rubber composite materials are machined to a flexibility skeleton. An enameled wire is wound on the flexibility skeleton. A compensation circle is wound on the flexibility skeleton. The enameled wire which is wound passes a test on rated current once. An insulating layer is arranged on the flexibility skeleton with the enameled wire, and the enameled wire passes the test. A shield layer is arranged outside the insulating layer. An output shielded wire is welded at one end of the shield layer. An output signal of the coils is tested again. A low-pressure injection molding insulation protecting layer is arranged outside the shield layer. The flexibility coil current transformer is flexible in flexibility, capable of being started and also randomly measured in a small space without closing a line, and simple, quick and convenient to install. Meanwhile, the output signal can be quickly connected to an oscilloscope, a data recorder or a multimeter by a connector.

Description

A kind of flexible coil current transformer

Technical field

The utility model relates to electrical equipment technical field, particularly a kind of flexible coil current transformer.

Background technology

Current transformer is the important component part of electric power system.The accuracy of its sensing measurement and reliability play a part basic in power system monitoring, analysis, control, particularly control gold, chemical industry, generating cause to improving constantly that large capacity, high voltage, miniaturization, the digital automation of electric power system requires, make the volume of traditional instrument transformer more and more large, insulation system is more and more complicated, and the difficulty of manufacturing is also more and more high.Simultaneously, magnetic hysteresis, magnetic saturation, the secondary that traditional instrument transformer exists can not be opened a way, the linearity is low, the accurate scope of Static and dynamic is little and the signal of output can not cooperate the problems such as digital intellectualization equipment, can not satisfy the demand of power system development.

Luo-coil is a kind of air core coil of special construction, it does not contain iron core,, bandwidth good without saturation problem, transient characterisitics, does not have short time thermal current and moving steady the influence of peak current, cooperate external shield technique to have good shielding character, be particularly useful for the measurement of pulse high current, D.C. high-current, high frequency occasion.All toward the intelligent digital development, Luo-coil only need provide the accurately demand of metrical information no-output power to the secondary device that is mated now, so the development trend of the fine adaptation electricity of Luo-coil system.

Present traditional electromagnetic current transducer also has a kind of method of opening air gap at iron circuit, by increasing magnetic resistance, reduce remanent magnetism to reach unsaturated when the large electric current of transient state, but owing to himself still be perception, can affect the waveform of tested electric current, truly reflected signal characteristic, and physical dimension bulky complex is not easy to install.

The utility model content

The utility model provides a kind of flexible coil current transformer, can measure arbitrarily in the small space of open-circuit line not, and simple installation is quick, and output signal can be connected to oscilloscope, data logger or universal instrument fast by connector.

To achieve these goals, the utility model provides following technical scheme:

A kind of flexible coil current transformer, it comprises:

Line body, output shielding conductor 106, plastic rubber lock catch 107 and integral amplifier 108, described line body comprises flexible back bone 101, enamelled wire 102, insulating barrier 103, screen 104, low-pressure injection molding insulating protective layer 105, wherein:

Be wound with enamelled wire on the described flexible back bone; described enamelled wire is wound with insulating barrier outward; described insulating barrier is outside equipped with screen; described screen is outside equipped with the low-pressure injection molding insulating protective layer; the link of described line body is provided with plastic rubber lock catch, and the screen of described line body connects integral amplifier by the output shielding conductor.

By implementing above technical scheme, have following technique effect: the flexible coil current transformer flexibility that the utility model provides can be opened flexibly, can also in the small space of open-circuit line not, measure arbitrarily, simple installation is quick, output signal can be passed through connector, be connected to fast oscilloscope, data logger or universal instrument.

Description of drawings

The structural representation of the flexible coil current transformer that Fig. 1 provides for the utility model.

Embodiment

In order better to understand the technical solution of the utility model, describe the embodiment that the utility model provides in detail below in conjunction with accompanying drawing.

The utility model embodiment provides a kind of flexible coil current transformer, and as shown in Figure 1, it comprises:

Line body, output shielding conductor 106, plastic rubber lock catch 107 and integral amplifier 108, described line body comprises flexible back bone 101, enamelled wire 102, insulating barrier 103, screen 104, low-pressure injection molding insulating protective layer 105, wherein:

Be wound with enamelled wire on the described flexible back bone; described enamelled wire is wound with insulating barrier outward; described insulating barrier is outside equipped with screen; described screen is outside equipped with the low-pressure injection molding insulating protective layer; the link of described line body is provided with plastic rubber lock catch, and the screen of described line body connects integral amplifier by the output shielding conductor.

The utility model also provides a kind of flexible coil current transformer manufacture method, and it comprises step:

A, silicon rubber composite material are processed into flexible back bone; Because the size of coil-induced electromotive force is directly proportional with the single-turn circular coil cross section, so bring impact on coil rack in order to reduce temperature, adopted low-expansion silicon rubber composite material, its coefficient of linear expansion is low to moderate: 1.2 * 10-5/ ℃, operating temperature range :-50～180 ℃, and silicon rubber has superior compression resistant deformation behavior, guarantee the consistency of coil section under varying environment, simultaneously for satisfying pliability and certain mechanical strength, hardness is controlled at 60 shore As, adopts silicon rubber formed one-tenth external diameter Ф 8.5mm flexible back bone.

B, on flexible back bone the coiling enamelled wire: flexible back bone one end is fixed on coil winding machine rotating shaft head, and the other end fixes on the concentric bearings frock, adjusts the dynamics at skeleton two ends, carries out the coiling of enamelled wire.

For coiling on flexible back bone, the parallel winding machine that prior art provides is difficult to satisfy the demand of coiling, need adopt spiral coil winding machine or existing parallel winding machine are transformed, to install parallel winding machine additional demand that a concentric bearings frock satisfies coiling at this, at first the end with flexible back bone is fixed on coil winding machine rotating shaft head, the other end of flexible back bone is fixed on the concentric bearings frock, adjust the dynamics at skeleton two ends, the beginning coiling, enamelled wire adopts Ф 0.10mm QZ-2/155 polyurethane enamel covered wire, wire turn winding displacement coefficient is controlled at 1.15, guarantee that turn-to-turn has certain interval, coil will evenly distribute, so that it is not follow-up can stacking formation between wire turn when coil is bent into annulus symmetrical, at this moment the induced potential equal and opposite in direction that in the little wire turn of two groups of symmetries, produces, opposite direction, the two is cancelled out each other, and disturbs but establishment is parallel to the interference of coil and current－carrying conductor is eccentric.

C, on described flexible back bone coiling compensation circle;

This compensation circle is loop line, and the enamelled wire of coiling is large wire turn among the step B.Because loop line is connected in the other direction with large wire turn, and loop line and large wire turn are positioned at same plane, therefore, for interference and the current－carrying conductor off-centre perpendicular to coil, the induced potential opposite direction that in large wire turn and loop line, produces, big or small approximately equal and cancel out each other, so the compensation circle structure of unrolling of coil, well disturb the compensating field.With the welding of starting of large wire turn pre-buried in the flexible back bone and loop line, the lead end of loop line is drawn from the ending end of the head end of loop line and large wire turn, like this loop line in coil section's circle that rewinds play the effect of compensation.

D, the primary side of the enamelled wire that turns to is tested by rated current; The primary side of the coil of the enamelled wire after the coiling by rated current, is tested secondary output end signal values with 6 half high-accuracy voltage tables and met design requirement.

E, at the flexible back bone with enamelled wire of test passes insulating barrier is set; Flexible coil after step D test passes, at coil periphery half-stack package (TP1) polytetrafluoroethylene (PTFE) insulating tape one deck, the teflin tape specification is: 180 ℃ of 15mmx0.1mm heatproofs.

F, outside described insulating barrier, screen is set; For the coupling capacitance of avoiding alternating electric field affects coil magnetic field, to to carry out shielding processing to flexible coil, screen is wanted reliable ground, the low-frequency alternating electric field is adopted metal screen layer, need adopt the material of high resistivity to the high-frequency alternating electric field, therefore, adopt the higher semiconductor extrusion coating paper of resistivity, with semiconductor extrusion coating paper coiling 1/3 stacked package one deck, 7 Ф 0.12 tinned wird W2 of bag connect semiconductor extrusion coating paper turn-to-turn in the bag screen, draw simultaneously ground connection after the screen welding of exporting shielding conductor.

G, at an end of described screen welding output shielding conductor;

H, the output signal of coil is carried out repetition measurement, test process is with step D;

I, set low the pressure injection insulating protective layer at described screen peripheral hardware.Satisfy the requirement of flexible coil external insulation and protection; need flexible coil is wrapped up with insulating barrier; adopt the mode of low-pressure injection molding; compare the sleeve pipe parcel; adopt the mode of low-pressure injection molding more firm to the protection of coil; flexible coil seals die casting fully in plastic cement, to its bending folding longer service life frequently.

The advantage of low-pressure injection molding: 1. injection pressure is extremely low, harmless Inside coil; 2. curing time fast (5～10S); 3. injection temperature low (180 ℃～200 ℃); 4. good airproof performance; 5. the low mould of pressure can adopt aluminum dipping form, and corresponding cost is also low; So select the mode of this kind low-pressure injection molding can effectively guarantee flexible coil electric property and structural requirement.

The technological process of flexible coil low-pressure injection molding: equipment adopts low-pressure injection molding machine, temperature parameter before the injection moulding: 190 ℃ of 185 ℃ of injection molding gun mouths of glue cylinder temperature temperature, 185 ℃ of sebific duct temperature; With coiling, the coil that bandages is put into and is adjusted the position in the injection mold, matched moulds, and injection time 12s guarantees that glue can be full of the injection moulding space.It is discontented punching not occur, the bad phenomenon such as bubble, pressurize 0.2Mpa, dwell time 8s, cooling time 30s, cooling is finished, mold open, the product that injection moulding is finished takes out.

More than a kind of flexible coil current transformer that the utility model embodiment is provided be described in detail, for one of ordinary skill in the art, thought according to the utility model embodiment, all will change in specific embodiments and applications, in sum, this description should not be construed as restriction of the present utility model.

Claims (1)

1. a flexible coil current transformer is characterized in that, comprising:

Line body, output shielding conductor (106), plastic rubber lock catch (107) and integral amplifier (108); described line body comprises flexible back bone (101), enamelled wire (102), insulating barrier (103), screen (104), low-pressure injection molding insulating protective layer (105), wherein:

Be wound with enamelled wire on the described flexible back bone; described enamelled wire is wound with insulating barrier outward; described insulating barrier is outside equipped with screen; described screen is outside equipped with the low-pressure injection molding insulating protective layer; the link of described line body is provided with plastic rubber lock catch, and the screen of described line body connects integral amplifier by the output shielding conductor.

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