CN215183468U

CN215183468U - Low partial discharge medium voltage sleeve

Info

Publication number: CN215183468U
Application number: CN202121370351.3U
Authority: CN
Inventors: 何林; 程福
Original assignee: Mianyang Fulin Electrical Insulation Material Technology Co ltd
Current assignee: Mianyang Fulin Electrical Insulation Material Technology Co ltd
Priority date: 2021-06-18
Filing date: 2021-06-18
Publication date: 2021-12-14
Anticipated expiration: 2031-06-18

Abstract

The utility model discloses a low partial discharge medium voltage sleeve, which is configured to comprise a sleeve for 15kV and below voltage grade, and a high voltage electrode which is connected with high voltage leading-out ends of different insulating media at intervals is arranged on the central axis of the sleeve; the low-voltage electrode and the high-voltage electrode are arranged concentrically, and the low-voltage electrode is provided with an extraction connecting piece in an embedded manner, wherein the extraction connecting piece is connected with low-voltage extraction ends of different insulating media. The utility model provides a medium voltage sleeve pipe is put in low office carries out reasonable design through the structure to medium voltage sleeve pipe for it can be applied to and correspond between different insulating medium and the different voltage demands and be connected, makes the field intensity between the high low voltage electrode the two more even, and the partial discharge volume is littleer under the rated voltage, has promoted the durability of product, has improved the stability of medium and low voltage electrical apparatus conductive terminal performance.

Description

Low partial discharge medium voltage sleeve

Technical Field

The utility model relates to a conductive connector between equipment structure, more specifically relate to one kind and be used for all kinds of well low voltage electrical apparatus, need electrically conduct between different insulating medium, and the unexpected great partial discharge's that appears medium voltage bushing.

Background

A Capacitor Voltage Transformer (CVT) is a voltage transformer which is divided by a series capacitor, then is subjected to voltage reduction and isolation by an electromagnetic transformer and is used as a meter, relay protection and the like, and the capacitor voltage transformer can also couple carrier frequency to a power transmission line for long-distance communication, remote measurement, selective high-frequency protection of the line, remote control, teletype and the like. Therefore, compared with the conventional electromagnetic voltage transformer, the capacitive voltage transformer has many advantages in terms of economy and safety, in addition to preventing ferromagnetic resonance caused by saturation of the iron core of the voltage transformer. The capacitor voltage transformer mainly comprises a capacitor voltage divider and a medium voltage transformer. The capacitive voltage divider consists of a porcelain bushing and a plurality of series capacitors arranged in the porcelain bushing, wherein the porcelain bushing is filled with insulating oil which keeps positive pressure of 0.1MPa, and steel corrugated pipes are used for balancing different environments to keep oil pressure, and the capacitive voltage divider can be used as a coupling capacitor to be connected with a carrier device. The medium voltage transformer consists of transformer, compensating reactor, lightning arrester and damping device inside sealed oil tank, and the space in the top of the oil tank is filled with nitrogen.

In practical operation, the capacitive voltage divider and the medium voltage transformer need to have low partial discharge, and the capacitive voltage divider and the medium voltage transformer are connected and need to be electrically isolated, so that the use requirement of the capacitive voltage divider in a specific occasion is ensured, and the accuracy of voltage measurement of a back-end device is ensured.

SUMMERY OF THE UTILITY MODEL

An object of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages which will be described later.

To achieve these objects and other advantages in accordance with the present invention, there is provided a low partial discharge medium voltage bushing, the low partial discharge medium voltage bushing configured to include:

the high-voltage bushing is used for a bushing with a voltage grade of 15kV or below, and a high-voltage electrode which is connected with high-voltage leading-out ends of different insulating media in an interval manner is arranged on the central axis of the bushing;

the low-voltage electrode and the high-voltage electrode are configured to be concentrically arranged, and the low-voltage electrode is provided with an extraction connecting piece in an embedded manner, wherein the extraction connecting piece is connected with low-voltage extraction ends of different insulating media;

wherein the high-voltage electrode is configured to be made of cylindrical copper material, the low-voltage electrode is configured to be made of copper net structure, and the low-voltage electrode is configured to be wrapped outside the sleeve at equal intervals;

and the low-voltage electrode, the high-voltage electrode and the low-voltage electrode and the outer side of the low-voltage electrode are respectively provided with a matched insulating layer, the insulating layers are obtained by adopting an unsaturated polyester glass fiber reinforced molding material SMC, and the end part of the leading-out connecting piece is configured to protrude 1-2mm out of the insulating layers.

Preferably, the low-voltage electrode is provided with an installation groove for limiting the leading-out connecting piece;

wherein, the low-voltage electrode is provided with a convex conical part at the position matched with the leading-out connecting piece.

Preferably, an electrostatic shielding layer is constructed between the low-voltage electrode and the high voltage;

wherein, a metal copper ring for supporting is arranged on the electrostatic shielding layer.

Preferably, the two ends of the low-voltage electrode are respectively provided with a connection threaded hole matched with the high-voltage leading-out ends of different insulating media.

Preferably, the low voltage electrode is externally provided with at least one boss coaxial therewith.

The utility model discloses at least, include following beneficial effect: one of which, the utility model discloses a structure to medium voltage bushing designs, make it can be used to in 15kV and following voltage class, all need play the electrically conductive effect between the different insulating medium of centre and expect its various middling pressure electric conduction places that have low partial discharge performance still simultaneously, make the field intensity between the high-low voltage electrode the two more even, the partial discharge volume is littleer under the rated voltage, the electric resistance of product has been promoted, the stability of well low voltage electrical apparatus conductive terminal performance has been improved, keep apart with unsaturated polyester glass fiber reinforcement molding material (SMC) material between high voltage electrode and the low voltage electrode simultaneously, guarantee the stability of equipment.

Secondly, this is novel through setting up copper network structure's low voltage electrode to the sleeve pipe outside for netted electrostatic shield has between low voltage electrode and the high voltage electrode, guarantees medium voltage sheathed tube job stabilization nature.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

Fig. 1 is a schematic structural view of a low partial discharge medium voltage bushing according to an embodiment of the present invention;

fig. 2 is a schematic cross-sectional structure of fig. 1.

Detailed Description

The present invention is further described in detail below with reference to the drawings so that those skilled in the art can implement the invention with reference to the description.

It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.

It should be noted that in the description of the present invention, the terms indicating the orientation or the positional relationship are based on the orientation or the positional relationship shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the indicated device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention.

In the description of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "sleeved/connected," "connected," and the like are to be construed broadly, such as "connected," which may be a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection via an intermediate medium, or a connection between two elements, and those skilled in the art will understand the specific meaning of the terms in the present invention in a specific context.

Furthermore, in the present disclosure, unless explicitly stated or limited otherwise, a first feature may be "on" or "under" a second feature in direct contact with the first and second features, or in indirect contact with the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Fig. 1 shows according to the utility model discloses a low office puts medium voltage bushing implementation form, medium voltage bushing is used in this voltage class, and all need play electrically conductive effect between middle different insulating medium and still expect its various middling pressure that have low office and put the performance simultaneously electrically conductive place, as the capacitive voltage transformer, all kinds of voltage dividers, oily medium voltage transformer, medium voltage switch etc. carry out the electrically conductive parts that insulate and keep apart, medium voltage bushing is configured to include:

the high-voltage connection structure comprises a sleeve 1 used for 15kV and below voltage classes, wherein a central axis of the sleeve is provided with high-voltage electrodes 2 which are in interval interconnection with high-voltage leading-out ends of different insulating media;

the low-voltage electrode 3 keeping a preset distance with the periphery of the high-voltage electrode is configured to be concentric with the high-voltage electrode, and the low-voltage electrode is provided with an embedded leading-out connecting piece 4 connected with low-voltage leading-out ends of different insulating media in an embedded mode, namely in actual operation, the low-voltage electrode is designed on a concentric circle keeping a certain distance with the high-voltage electrode, the low-voltage electrode of the concentric circle structure adopts a copper net-shaped design and is provided with the leading-out connecting piece of an embedded structure, the whole net-shaped length is coaxial with the high-voltage electrode, the low-voltage electrode has an electric field shielding function, so that an electric field is more uniform under the working voltage of the low-voltage electrode, in the structure, in order to facilitate installation, two ends outside the sleeve are led out of the high-voltage electrode, the low-voltage shielding electrode is led out by the leading-out connecting piece on the side surface of the low-voltage electrode, and further, the low-voltage electrode and the high-voltage electrode are designed in a coaxial mode, the effect is ensured to have uniformity when the two are subjected to partial discharge and functional electrical shielding, so that the working stability and the service life of the structural member are ensured;

the high-voltage electrode is configured to be made of cylindrical copper materials, the low-voltage electrode is configured to be in a copper net structure, the low-voltage electrode has a shielding function by adopting a net structure design, and the low-voltage electrode is configured to be equidistantly coated outside the sleeve;

the insulation layer 5 is matched with the insulation layer arranged inside the low-voltage electrode, between the high-voltage electrode and the low-voltage electrode and outside the low-voltage electrode, the insulation layer is formed by adopting an unsaturated polyester glass fiber reinforced molding material SMC, the insulation layer is formed by insulation between SMC insulation materials and insulation to the ground, the performance is reliable, the insulation strength is high, the reliability of equipment is guaranteed, and the end part of the leading-out connecting piece is arranged to protrude 1-2mm of the insulation layer and used for guaranteeing the reliability and effectiveness of connection of the leading-out connecting piece and an external structure.

Taking a capacitive voltage transformer as an example, a medium-voltage bushing is arranged between a capacitive voltage divider and a medium-voltage transformer and is connected with the capacitive voltage divider and the medium-voltage transformer at intervals by taking a high-voltage electrode as a conductor, and the high-voltage electrode penetrating through the bushing and extending outwards in the structure electrically connects a high-voltage leading-out end of the capacitive voltage divider and a high-voltage leading-out end of the medium-voltage transformer so as to ensure the matching between structural members in equipment, while the length of the bushing is smaller than that of the conductor, namely, the bushing and the high-voltage leading-out end are connected in an isolated manner so as to ensure that the respective work is not influenced and not interfered with each other;

the low-voltage electrode cladding sets up in the sleeve pipe outside, and is provided with on the low-voltage electrode outer wall and draws forth the connecting piece with capacitive voltage divider, well voltage transformer matched with for draw forth the end with capacitive voltage divider, well voltage transformer's low pressure and be connected, accomplish the electrical property interconnection between the equipment structure spare, and the design of cladding formula for the sleeve pipe is all held and is kept apart with the outside inside low-voltage electrode.

In practical operation, the low-voltage electrode is similar to a metal sleeve with a double-layer hollow structure, a cavity for limiting the sleeve and the high-voltage electrode is arranged in the metal sleeve, the sleeve and the high-voltage electrode extending out of the sleeve are completely coated in the metal sleeve for electrical isolation through the design of the cavity, meanwhile, the hollow structure is designed, so that an accommodating space is formed in the hollow structure, in practical operation, through the accommodating structure design of the cavity, the high-voltage electrode for conducting cannot leak and loosen after being filled and insulated within the temperature range of (-60-120) DEG C, in practical processing operation, an SMC insulating material is of a pasty structure, and after the SMC insulating material is filled, the SMC insulating material is subjected to chemical change through high temperature to form the insulating layer of the scheme.

In another example, as shown in fig. 1, a mounting groove 6 for defining the leading-out connectors is provided on the low-voltage electrode, and in order to solve the insulation problem between different mediums, a mounting groove (mounting hole) for positioning, sealing and isolating the two leading-out connectors and fixing the sleeve is provided on the mounting reference surface of the low-voltage electrode;

wherein, the low-voltage electrode is provided with a convex conical part 7 at the position matched with the leading-out connecting piece. In this kind of structure, adopt embedded connecting piece, its inside has the mounting hole that can supply power line or male joint to insert or screw in, guarantees the degree of fit between the equipment, sets up the matched with mounting groove on the low-voltage electrode simultaneously, and its effect lies in prescribing a limit to the position of drawing forth the connecting piece, and the effect of toper portion lies in drawing forth the formula and prescribes a limit to the connecting piece twice, guarantees the stability of work simultaneously, increases its surface area simultaneously, increases mechanical strength.

As shown in fig. 1, in another example, an electrostatic shielding layer 8 is constructed between the low-voltage electrode and the high voltage, the low-voltage electrode with a copper mesh structure is arranged outside the sleeve, so that the mesh electrostatic shielding layer is arranged between the low-voltage electrode and the high-voltage electrode, and the mesh structure of the low-voltage electrode ensures the stability of the insulating material SMC filled in the middle of the sleeve during the die pressing, and in the die pressing process, the mesh on the low-voltage electrode can break up the bubbles generated in the die pressing process and completely extrude the air, thereby ensuring the filling degree of the insulating material in the low-voltage electrode, and effectively preventing the problem that the service life of the equipment is influenced by the breakdown of the medium-voltage sleeve due to the large light, electricity and heat generated in the work;

the electrostatic shielding layer is provided with a supporting metal copper ring 9, and in order to ensure that a good concentric electric field is formed between the electrostatic shielding layer of the low-voltage electrode and the high-voltage electrode, the low-voltage electrostatic shield is provided with a plurality of metal supporting copper rings for reducing the deformation of the electrostatic shielding layer in the SMC die pressing process. In the structure, in actual operation, when the insulating material is filled in the low-pressure sleeve, the filling material SMC in the low-pressure sleeve generates a certain extrusion acting force in mould pressing, so that the low-pressure sleeve is locally deformed to influence the coaxiality of the low-pressure sleeve, a matched support ring is limited between the low-pressure sleeve and the low-pressure sleeve, the axial acting force of the support ring is guided and supported, the deformation of the structure is reduced, and the physical stability of the structure is not influenced; in actual operation, the outer side wall of the sleeve is also provided with a limiting groove 10 matched with the support ring, the limiting groove 10 is used for partially supporting and accommodating the support ring, secondary extrusion and deformation of the outer wall of the functional guide pipe caused by excessive protrusion of the limiting groove are prevented, and the stability of a structural part in the processing process of the limiting groove is ensured.

In another example, as shown in fig. 1, connection threaded holes 11 matched with high-voltage leading-out ends of different insulating media are respectively formed at two ends of the low-voltage electrode, the threaded holes are used for connecting and fixing the different external insulating media, and the high-voltage electrode is electrically connected with the different insulating media through the threaded holes.

As shown in fig. 1-2, in another example, at least one boss 12 coaxial with the low voltage electrode is disposed outside the low voltage electrode, and a plurality of fixing holes 13 may be uniformly distributed thereon as required, in this structure, in actual operation, the function conduit needs to be coaxial with the conductive shaft, and the roundness thereof is kept unaffected, and the physical structure stability of the device may cause some influence, and the physical structure stability of the function conduit is adjusted by disposing the coaxial boss, and meanwhile, the coaxially extending circular ring structure design thereof may not affect the partial discharge and the screen effect of the device, and further, a matching fixing hole may be disposed thereon, and may be matched with the structural member of the device to complete the fixing and the installation, so as to have a better matching degree.

The above embodiments are merely illustrative of a preferred embodiment, but not limiting. When the utility model is implemented, the proper replacement and/or modification can be carried out according to the requirements of users.

The number of apparatuses and the scale of the process described here are intended to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.

While embodiments of the invention have been disclosed above, it is not intended to be limited to the applications listed in the specification and the examples. It can be applicable to various and be fit for the utility model discloses a field completely. Additional modifications will readily occur to those skilled in the art. The invention is therefore not to be limited to the specific details and illustrations shown and described herein, without departing from the general concept defined by the claims and their equivalents.

Claims

1. A low partial discharge medium voltage bushing, wherein the medium voltage bushing is configured to comprise:

2. The low partial discharge medium voltage bushing according to claim 1, wherein the low voltage electrode is provided with a mounting groove defining a lead-out connector;

3. The low partial discharge medium voltage bushing according to claim 1, wherein an electrostatic shield is constructed between the low voltage electrode and the high voltage;

4. The low partial discharge medium voltage bushing according to claim 1, wherein the low voltage electrode has connection screw holes at both ends thereof for matching with high voltage terminals of different insulating media.

5. The low partial discharge medium voltage bushing according to claim 1, wherein the low voltage electrode is externally provided with at least one boss coaxial therewith.