CN207264893U - A kind of single-phase earthing voltage transformer - Google Patents

Abstract

The utility model discloses a kind of single-phase earthing voltage transformer, it is related to voltage sensor field, including iron core, secondary coil, primary winding and insulating layer, it is characterized in that, the first insulating layer is equipped between iron core and secondary coil, the second insulating layer is equipped between secondary coil and primary winding, first screen layer is equipped between second insulating layer and primary winding, the primary winding is externally provided with secondary shielding layer, and the width in the first screen layer and secondary shielding layer mandrel direction in the core is more than the width in primary winding mandrel direction in the core；Two end faces of the secondary shielding layer are equipped with ring shaped conductive pipe.The length that the utility model solves the primary shield of existing single-phase earthing voltage transformer is slightly narrower or wide than the width of primary winding conducting wire, after so setting, the electric field intensity of coil end face edge dielectric is high, the problem of causing shelf depreciation qualification rate relatively low.

Description

A kind of single-phase earthing voltage transformer

Technical field

It the utility model is related to voltage sensor field, more particularly to a kind of single-phase earthing voltage transformer.

Background technology

Voltage transformer and transformer's type are the instruments of the voltage on conversion line seemingly.Voltage transformer mainly wraps Primary winding, secondary coil, iron core and insulator are included, when in use, when applying a voltage U1 on primary winding, in iron A magnetic flux φ is just produced in the heart, according to the law of electromagnetic induction, then a secondary voltage U2 is just produced in secondary coil.Pass through Change once or secondary winding the number of turn, it is possible to produce different primary voltages and secondary voltage ratio, you can form it is not year-on-year Voltage transformer.High voltage is mainly converted into low-voltage by voltage transformer in proportion, and voltage transformer primary side is connected on Primary system, secondary side joint measuring instrumentss, relay protection etc., is mainly used in measuring voltage, electric energy in power system switch cabinet Or the important part of relay protection.The primary winding outer layer of middle pressure single-phase earthing voltage transformer coil can all set primary shielding Layer, it is therefore intended that shielding external electrical field, balanced coil electric field.Insulate the length of primary shield that most of producers set at present It is slightly narrower or wide than the width of primary winding conducting wire, after so setting, the electric field intensity of coil end face edge dielectric Height, causes shelf depreciation qualification rate relatively low.

Utility model content

The purpose of this utility model is that：To solve the primary winding end surface side edge of existing single-phase earthing voltage transformer The electric field intensity of dielectric is high, the problem of causing shelf depreciation qualification rate relatively low, and the utility model provides single in technique Phase earthed voltage transformer.

The technical solution of the utility model is as follows：

A kind of single-phase earthing voltage transformer, including iron core, secondary coil, primary winding and insulating layer, it is characterised in that The first insulating layer is equipped between iron core and secondary coil, is equipped with the second insulating layer between secondary coil and primary winding, described First screen layer is equipped between two insulating layers and primary winding, the primary winding is externally provided with secondary shielding layer, first screen The width for covering layer and secondary shielding layer mandrel direction in the core is more than the width in primary winding mandrel direction in the core；It is described Two end faces of secondary shielding layer are equipped with ring shaped conductive pipe.

Further, the first screen layer and the secondary shielding layer are of same size in mandrel direction in the core, and institute The width for stating first screen layer and secondary shielding layer mandrel direction in the core is more than primary winding mandrel direction in the core The part of width is the 1/3 of primary winding axial width.

Preferably, the material of the ring shaped conductive pipe is the one or more in aluminium, copper, tungsten, nickel or iron.

After using the above scheme, the beneficial effects of the utility model are：

(1) first screen layer and secondary shielding layer stretch out make in coil end face outside primary winding end face with primary winding body In same capacitance, very little is differed with coil body in primary winding end regions electric field, reduces generation shelf depreciation Possibility, so as to improve the qualification rate of shelf depreciation.

(2) since first screen layer and secondary shielding layer itself are relatively thin, its both ends is outside primary winding, in secondary shielding Two end faces increase ring shaped conductive pipe of layer, when voltage transformer works, improves first screen layer and secondary shielding layer is held in itself The electric field in face is concentrated, and weakens the electric field strength for leading secondary shielding layer edge, further reduces the probability for producing shelf depreciation.

Brief description of the drawings

Fig. 1 is the lateral partial structurtes sectional view of the utility model；

Front views of the Fig. 2 for the coil winding of the utility model after good；

Side views of the Fig. 3 for the coil winding of the utility model after good；

Fig. 4 is the voltage transformer external structure front view of the utility model；

Fig. 5 is the voltage transformer external structure side view of the utility model；

Marked in figure：1- iron cores, 2- secondary coils, 3- primary windings, the first insulating layers of 4-, the second insulating layers of 5-, 6- One shielded layer, 7- secondary shielding layers, 8- ring shaped conductive pipes, 9- interlayer insulating films, the connection of 10- welding plates.

Embodiment

The following is a combination of the drawings in the embodiments of the present utility model, the technical solution in the present embodiment is carried out clear, complete Site preparation describes, it is clear that described embodiment is only the part of the embodiment of the utility model, rather than whole implementation Example.Based on the embodiment in the utility model, those of ordinary skill in the art are obtained without making creative work The every other embodiment obtained, shall fall within the protection scope of the present invention.

Figure be the utility model voltage transformer in the part that makes improvements, if shown, the utility model Single-phase earthing voltage transformer, including iron core 1, secondary coil 2, primary winding 3 and insulating layer, between iron core 1 and secondary coil 2 Equipped with the first insulating layer 4, be equipped with the second insulating layer 5 between secondary coil 2 and primary winding 3, second insulating layer 5 with once First screen layer 6 is equipped between coil 3, the primary winding 3 is externally provided with secondary shielding layer 7, the first screen layer 6 and second The width in the mandrel direction in the core 1 of shielded layer 7 is more than the width in the mandrel direction in the core 1 of primary winding 3；First screen Two end faces for covering layer 6 and secondary shielding layer 7 are equipped with ring shaped conductive pipe 8.First screen layer 6 and secondary shielding layer 7 are partly to lead Electric paper, first screen layer 6 are conducting papers, are directly grounded after connecting together with ground terminal N once；Secondary shielding layer 7 is outer The metal layer of conducting paper is surrounded by, is connected together with a high-pressure side A.Fig. 2 and Fig. 3 is inside complete voltage transformer Structure chart.

Primary winding 3 and secondary coil 2 use common enameled wire, the insulation of the first insulating layer 4, second in the utility model Layer 5 and interlayer insulating film 9 are using PMP materials, and for primary winding 3, primary winding 3 is obtained by conducting wire sandwich wound Arrive, be designed with interlayer insulating film 9 between each layer line circle of primary winding 3, A, N in figure are the leading-out terminal of primary winding 3； For secondary coil 2, secondary coil 2 is only containing the leading-out terminal that a, n in one layer of electric wire figure are secondary coil 2.After for convenience Continuous mutual induction of voltage answers device to prepare, and welding connecting plate 9 is equipped with the lower section of secondary coil 2, after the completion of coil winding, passes through welding Connecting plate 9 is fixed in mould, the region with gap between primary winding and secondary coil, and primary winding and secondary coil Outside, be intended to fill insulant, these all be those skilled in the art notification technique, do not did explanation herein.Voltage As shown in Figure 4 and Figure 5, n ends and N-terminal ground connection, a sections are connected to external meters, high-pressure side A to external structure after mutual inductor encapsulation It is connected in three phase network.Stretched out in first screen layer 6 and secondary shielding layer 7 makes primary winding 3 in 3 end face of primary winding It is in outside end face with 3 body of primary winding in same capacitance, in electric field and the primary winding 3 of 3 end regions of primary winding The electric field difference very little of body, reduces the possibility for producing shelf depreciation, so as to improve the qualification rate of shelf depreciation.

Since first screen layer and secondary shielding layer itself are relatively thin, its both ends is outside primary winding, in secondary shielding layer Two end faces increase ring shaped conductive pipe, when voltage transformer works, improve first screen layer and secondary shielding layer end face itself Electric field concentrate, weaken and lead the electric field strength at secondary shielding layer edge, further reduce the probability for producing shelf depreciation.

On the contrary, still from the angle analysis of a capacitance, as using common first screen layer 6 and secondary shielding layer 7 Set-up mode, first screen layer 6 and secondary shielding layer 7 are big unlike the shared width of primary winding 3,3 end regions of primary winding Dielectric constant of the electric field of certain point corresponding thereto in the position of electrode and medium is related.Because the number of turn base of 3 every layer of primary winding This is consistent, and voltage between layers is also just essentially identical, and interfloor distance is also identical, then a conducting wire end face interlayer electric field with regard to basic Unanimously；For layer insulation end face, due to the difference of dielectric and the dielectric constant of layer insulation, electric-force gradient is uneven in addition It is even, cause electric field to be concentrated more obvious.

The first screen layer 6 and the secondary shielding layer 7 are of same size in mandrel direction in the core 1, and described first The width in shielded layer 6 and secondary shielding layer 7 mandrel direction in the core 1 is more than the width in the mandrel direction in the core 1 of primary winding 3 The part of degree is the 1/3 of 3 axial width of primary winding.For existing single-phase earthing voltage transformer, the width of its primary shielding Degree generally adds the width of first screen layer 6 and secondary shielding layer 7 without departing from the width of a conducting wire coiling, the utility model Greatly, it is specific that the width of increasing must be set as to the 1/3 of 3 axial width of primary winding, if width is excessive, can influence whole single-phase The overall volume of earthed voltage transformer, if width is too small, conducting loop-shaped pipe is inconvenient to be installed on end face, does not just reach above The beneficial effect, therefore, after test of many times, finds first screen layer 6 and secondary shielding layer 7 mandrel in the core 1 The width in direction be more than primary winding 3 in the core 1 the width in mandrel direction part be 3 axial width of primary winding 1/3 It is best distance.

As shown in Fig. 2, ring shaped conductive pipe 8 is one kind in solid torus or netted ring, the material of ring shaped conductive pipe 8 is aluminium, One or more in copper, tungsten, nickel or iron, these metals are all common metals, convenient to obtain, and processing is simple.

It is obvious to a person skilled in the art that the utility model is not limited to the details of above-mentioned one exemplary embodiment, and And in the case of the spirit or essential attributes without departing substantially from the utility model, it can realize that this practicality is new in other specific forms Type.Therefore, in all respects, the present embodiments are to be considered as illustrative and not restrictive, this practicality is new The scope of type is indicated by the appended claims rather than the foregoing description, it is intended that the equivalency fallen in claim is contained All changes in justice and scope are embraced therein.Any reference numeral in claim should not be considered as limitation Involved claim.

Moreover, it will be appreciated that although the present specification is described in terms of embodiments, not each embodiment is only wrapped Containing an independent technical solution, this narrating mode of specification is only that those skilled in the art should for clarity Using specification as an entirety, the technical solutions in the various embodiments may also be suitably combined, forms those skilled in the art It is appreciated that other embodiment.

Claims (4)

1. a kind of single-phase earthing voltage transformer, including iron core (1), secondary coil (2), primary winding (3) and insulating layer, iron core (1) the first insulating layer (4) is equipped between secondary coil (2), it is exhausted that second is equipped between secondary coil (2) and primary winding (3) Edge layer (5), it is characterised in that it is equipped with first screen layer (6) between second insulating layer (5) and primary winding (3), described one Secondary coil (3) is externally provided with secondary shielding layer (7), and the first screen layer (6) and secondary shielding layer (7) are in iron core (1) central shaft The width in direction is more than width of the primary winding (3) in iron core (1) central axis direction；Two ends of the secondary shielding layer (7) Face is equipped with ring shaped conductive pipe (8).

A kind of 2. single-phase earthing voltage transformer according to claim 1, it is characterised in that the first screen layer (6) It is of same size with the secondary shielding layer (7) in iron core (1) central axis direction, and the first screen layer (6) and secondary shielding Layer (7) is more than primary winding (3) in the part of the width of iron core (1) central axis direction in the width of iron core (1) central axis direction For the 1/3 of primary winding (3) axial width.

A kind of 3. single-phase earthing voltage transformer according to claim 1, it is characterised in that the ring shaped conductive pipe (8) For one kind in solid torus or netted ring.

4. a kind of single-phase earthing voltage transformer according to claim 1 or 3, it is characterised in that ring shaped conductive pipe (8) Material is the one or more in aluminium, copper, tungsten, nickel or iron.