CN111180165A

CN111180165A - Transformer bushing's head subassembly and transformer bushing

Info

Publication number: CN111180165A
Application number: CN202010073252.2A
Authority: CN
Inventors: 马斌; 黄从鹏; 孙略; 孙中源
Original assignee: Jiangsu Shenma Electric Power Co Ltd
Current assignee: Jiangsu Shenma Electric Power Co Ltd
Priority date: 2020-01-21
Filing date: 2020-01-21
Publication date: 2020-05-19

Abstract

The invention discloses a head assembly of a transformer bushing, which comprises an end cover and a cable joint; the end cover comprises an upper surface and a lower surface which are opposite, a first through hole is formed in the center of the end cover, a convex ring is arranged on the upper surface and surrounds the first through hole, and at least two grooves are formed in the end face of the convex ring; the cable joint passes through the first through hole, the cable joint is provided with at least two pin holes, the pin passes through the groove and is fixed in the at least two pin holes, and the pin is fixedly connected with the groove, so that the relative position of the cable joint and the convex ring is fixed. The invention also discloses a transformer bushing, the head component of the transformer bushing is convenient to mount and dismount, and the problem of heating of the head of the transformer bushing can be solved.

Description

Transformer bushing's head subassembly and transformer bushing

Technical Field

The application relates to the technical field of power transmission insulating equipment, in particular to a head assembly of a transformer bushing and the transformer bushing.

Background

The power transformer is one of the most important and expensive critical power devices in the power system, and the transformer bushing is one of the critical parts of the transformer, and the electrical performance of the transformer bushing directly affects the operational reliability and safety of the transformer.

At present, at current transformer bushing head, it is fixed with cable joint that the trompil that passes the end cover through the cylindric lock is many, makes cable joint unsettled setting in the current-conducting tube, has following problem: the diameter of the opening hole is larger than that of the cylindrical pin, so that the cable joint has the risk of jumping up and down along with the vibration of the transformer sleeve, and the head assembly is heated due to the discharge; if the mode of bending the pin is adopted, the follow-up sleeve pipe is inconvenient to disassemble, and the time and the labor are wasted and the efficiency is low because the hole positions need to be aligned when the pins are inserted into the installation sleeve pipe.

Disclosure of Invention

In view of the defects of the prior art, one of the objectives of the present invention is to provide a header assembly of a transformer bushing, which is convenient to mount and dismount and can solve the problem of heat generation of the header of the transformer bushing.

In order to achieve the purpose, the technical means adopted by the invention are as follows: a head assembly of a transformer bushing comprises an end cover and a cable joint; the end cover comprises an upper surface and a lower surface which are opposite, a first through hole is formed in the center of the end cover, a convex ring is arranged on the upper surface and surrounds the first through hole, and at least two grooves are formed in the end face of the convex ring; the cable joint passes through the first through hole, the cable joint is provided with at least two pin holes, the pin passes through the groove and is fixed in the at least two pin holes, and the pin is fixedly connected with the groove, so that the relative position of the cable joint and the convex ring is fixed.

The pin is fixedly connected with the groove, so that the relative position of the cable joint and the convex ring is fixed, the cable joint cannot jump along with the vibration of the transformer bushing, and the head of the transformer bushing cannot generate heat due to unstable current; and the pin is fixedly connected with the groove, so that the installation and the disassembly are convenient, and the installation, the operation and the maintenance are convenient.

Preferably, the number of the pin holes is two, and the axes of the pin holes are on the same straight line; more preferably, the axes of the pin holes are located on the same diameter of the cable connector, so that the best stress balance can be achieved, and the processing difficulty and the matching difficulty are effectively reduced.

Preferably, the two pin holes are communicated with each other in the cable joint; only one pin shaft can be adopted and directly penetrates through the pin hole, so that the connection between the pin shaft and the cable connector is more convenient and reliable, and the stress is more balanced.

Preferably, the groove is a U-shaped groove, and the end part of the pin is a cylinder; the U-shaped groove and the cylindrical pin are more convenient to machine and match.

Preferably, the pin protrudes from the end face of the convex ring; the radial height of pin tip is greater than the recess degree of depth promptly for after the pin passed the recess, the pin protrusion in the terminal surface of bulge loop, can adopt the mode that compresses tightly to be fixed in the recess with the pin, provide simple and convenient reliable mode for the fixed of pin.

More preferably, head subassembly still includes binding post, binding post and end cover fixed connection, binding post compress tightly the pin and form the tight fit, can further guarantee to make cable joint with the relative position of bulge loop is fixed, can not take place to rock, solves the head problem of generating heat.

Preferably, the wiring terminal comprises a wiring part, an accommodating part and a connecting part, wherein the accommodating part is provided with a stepped inner wall and a stepped surface, the stepped surface abuts against the end surface of the convex ring, and the connecting part abuts against the upper surface; the shape of the inner wall of the wiring terminal is matched with that of the cable joint so as to be sleeved on the periphery of the cable joint and be reliably connected.

Preferably, the accommodating part is divided into a first accommodating part and a second accommodating part by taking the stepped surface as a boundary, a spring contact finger is arranged on the cable connector, and the spring contact finger abuts against the inner wall of the first accommodating part, so that the first accommodating part is electrically connected with the cable connector; the second accommodating part is used for accommodating the convex ring; the spring contact fingers are stably electrically connected with the cable joint, so that the equipotential of the head assembly can be kept, and the problem of head heating is solved.

In view of the defects of the prior art, the invention also aims to provide a transformer bushing which is simple in structure, convenient to mount and dismount and free of the problem of head heating.

The transformer bushing comprises the head assembly.

Preferably, the transformer bushing further comprises a conductive tube, the conductive tube is attached to the inner wall of the first through hole, and the cable joint is inserted into the conductive tube and is not in contact with the conductive tube; the cable joint is arranged in the conductive pipe in a hanging manner, so that the electric conduction is avoided, unstable electric connection is avoided, and the head of the transformer bushing is prevented from generating heat.

Drawings

FIG. 1 is a cross-sectional view of a head assembly 100 according to a first embodiment of the present invention;

FIG. 2 is a schematic perspective view of a head assembly 100 according to a first embodiment of the present invention;

FIG. 3 is a cross-sectional view of a head assembly 200 according to a second embodiment of the present invention;

fig. 4 is a sectional view of a connection terminal 203 according to a second embodiment of the present invention;

fig. 5 is a partial cross-sectional view of a transformer bushing 1000 according to a third embodiment of the present invention;

fig. 6 is an overall schematic diagram of a transformer bushing 1000 according to a third embodiment of the present invention.

Detailed Description

As required, detailed embodiments of the present invention are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed manner, including employing various features disclosed herein in combination with features that may not be explicitly disclosed herein.

The first embodiment is as follows:

as shown in fig. 1-2, the present embodiment provides a header assembly 100 of a transformer bushing, the header assembly 100 including an end cap 101 and a cable connector 102; the end cover 101 comprises an upper surface 1011 and a lower surface 1012 which are opposite, a first through hole 1013 is arranged at the center of the end cover 101, a convex ring 1014 is arranged around the first through hole 1013 at the upper surface 1011, and the first through hole 1013 and the convex ring 1014 are coaxially arranged so as to facilitate later assembly; in this embodiment, the inner diameter of the collar 1014 is equal to the diameter of the first through hole 1013, and it is understood that in other embodiments, the inner diameter of the collar is not equal to the diameter of the first through hole, that is, the inner wall of the collar and the inner wall of the first through hole are not on the same curved surface.

In this embodiment, the cable connector 102 passes through the first through hole 1013, the end surface of the collar 1014 is provided with two grooves 1015, and the cable connector 102 is provided with two pin holes 1022. In other embodiments, the number of the grooves on the end face of the protruding ring may be three, four or more, as long as the corresponding pin holes are also provided on the cable joint, and it is necessary to ensure the mechanical strength of the cable joint at the same time.

In this embodiment, the pin 1021 passes through the groove 1015 to be fixed in the two pin holes 1022, and the pin 1021 is fixedly connected with the groove 1015, so that the relative positions of the cable connector 102 and the convex ring 1014 are fixed; in this embodiment, the pin 1021 and the groove 1015 are fixedly connected, and can adopt glue binding, interference fit and other modes, so long as installation and disassembly are convenient, and permanent damage to components and parts can not be caused. Pin 1021 and pin hole 1022 may be secured with a threaded fit, or pin 1021 may be glued into pin hole 1022. It can be understood that, in this embodiment, the arrangement of the pin 1021 and the groove 1015 changes the conventional way of punching on the convex ring, and since the hole is punched on the convex ring, the diameter of the hole is inevitably larger than the diameter of the end of the pin, a gap exists between the pin and the hole on the convex ring, and under the condition that the whole transformer bushing vibrates, a cable joint connected with the convex ring through the pin jumps along with the jumping of the pin, so that the electrical connection between the cable joint and other components is unstable, and the head of the transformer bushing releases heat; the method also changes the prior method of bending the pin on the basis of punching the convex ring so as to prevent the cable joint from jumping, the pin is permanently damaged by the method, subsequent disassembly and maintenance cannot be carried out after the assembly is finished, even after the problem is found in the assembly stage, the head assembly can be only completely replaced and scrapped to stop the damage in time, and the manufacturing cost and the assembly risk are increased.

In the present embodiment, the number of the pin holes 1022 is two, and the axes of the two pin holes 1022 are on the same straight line; furthermore, the axes of the two pin holes 1022 are located on the same diameter of the cable connector 102, so that the best stress balance can be achieved, and the processing difficulty and the matching difficulty are low. In other embodiments, the axes of the two pin holes may not be on the same diameter of the cable joint, but the axes of the two pin holes may still be on the same line, i.e., on any line passing through the circumference of the torus. In other embodiments, the axes of the two pin holes may be at an angle to each other, so long as the securement of the pin in the cable joint is facilitated.

In this embodiment, the two pin holes 1022 penetrate each other in the cable joint 102, so that the installation margin of the pin 1021 is increased, and the pin 1021 with different lengths can be adapted. In addition, in other implementations, a pin shaft can be adopted and directly penetrates through the pin hole, so that the connection between the pin shaft and the cable connector is more reliable, and the stress is more balanced.

In this embodiment, the groove 1015 is a U-shaped groove, and the end of the pin 1021 is a cylinder; the U-shaped groove and the cylindrical pin are more convenient to machine and match. In other embodiments, the groove may have other shapes, such as rectangular, irregular, etc., as long as it has a shape fit with the pin end and has high fixing strength, i.e., the groove is tightly fitted with the pin end, and no play exists.

In this embodiment, the cable connector 102 is located at one end of the lower surface 2012 of the end cap 201 and is provided with a connecting hole, which can be connected to a cable.

In the header assembly 100 of the present embodiment, the pin 1021 is fixedly connected with the groove 1015, so that the relative position of the cable connector 102 and the convex ring 1014 is fixed, and the cable connector 102 does not jump along with the vibration of the transformer bushing, and the head of the transformer bushing does not generate heat due to unstable current; and the pin 1021 and the groove 1015 are fixedly connected, installed and detached conveniently, and are convenient to install, operate and maintain.

Example two:

as shown in fig. 3, the present embodiment further provides another transformer bushing head assembly 200, and the difference from the first embodiment is that the head assembly 200 further includes a terminal 203, and the terminal 203 is fixedly connected to the end cap 201. The terminal 203 is an electrical connection component of the transformer bushing for making electrical connection with other devices.

In this embodiment, the pin 2021 protrudes from the end surface of the bulge loop 2014; i.e., the radial height of the end of the pin 2021 is greater than the depth of the groove, the pin 2021 can be fixed in a pressing manner, thereby providing a simple and reliable way for fixing the pin 2021.

In this embodiment, specifically, the terminal 203 presses the pin 2021 to form a tight fit, which can further ensure that the relative position between the cable connector 202 and the collar 2014 is fixed, so that no shaking occurs, and the problem of head heat generation is solved.

As shown in fig. 4, in the present embodiment, the connection terminal 203 includes a connection portion 2031, an accommodating portion 2032, and a connection portion 2033, the accommodating portion 2032 is provided with a stepped inner wall and has a stepped surface 2037, the stepped surface 2037 abuts against an end surface of the male ring 2014, and the connection portion 2033 abuts against an upper surface 2011; the shape of the inner wall of the wiring terminal 203 is matched with the shape of the cable connector 202 so as to be sleeved around the cable connector 202, and the connecting part 2033 is fixedly connected with the end cover 201 and can adopt fixed connection modes such as screw connection or adhesive connection; the inner wall of the terminal 203 is pressed against the end face of the collar 2014 and the pin 2022 to securely fix the cable connector 202 and prevent the cable connector from jumping due to vibration of the transformer bushing. In other embodiments, the terminal may have other external shapes, and the inner wall may be shaped such that the terminal can press the pin and be fixedly connected to the end cap to fix the relative position of the cable connector and the collar.

In this embodiment, the connecting portion 2033 is uniformly provided with a plurality of through holes 2034, the upper surface 2011 of the end cap 201 is provided with a plurality of threaded holes corresponding to and matching with the through holes 2034, and the end cap 201 and the connecting portion 2033 are fixedly connected by screws. The screw connection strength is high, so that the inner wall of the terminal 203 can be tightly pressed against the end surface of the convex ring 2014, and the detachment of the terminal 203 is not hindered. In other embodiments, the fixing manner of the end cover and the connecting portion may also adopt other reliable connecting manners such as bolt connection, or a mixed manner of bolt connection and glue joint.

In this embodiment, a sealing groove 2017 is formed in the upper surface 2011 of the end cap 201, and a sealing ring (not shown in the figure) is disposed between the end cap 201 and the connecting portion 2033, so that the sealing performance between the end cap 201 and the connection terminal 203 can be improved, when the header assembly 200 is mounted on a transformer bushing, the oil leakage phenomenon does not occur at the header assembly, and the sealing performance and the electrical performance of the transformer bushing are further ensured. In other embodiments, a sealing groove may be disposed at a contact position of the connecting portion and the upper surface of the end cap, and a sealing ring is disposed in the sealing groove.

In this embodiment, the accommodating portion 2032 is divided into a first accommodating portion 20321 and a second accommodating portion 20322 by taking the stepped surface 2037 as a boundary, the cable connector 202 is provided with a spring contact finger 2023, specifically, an inner wall of the first accommodating portion 20321 is provided with an annular groove, the spring contact finger 2023 is accommodated in the annular groove, the spring contact finger 2023 abuts against the inner wall of the first accommodating portion 20321, so that the first accommodating portion 20321 is electrically connected to the cable connector 202; the second receiving portion 20322 receives the collar 2014; the spring fingers 2023 provide a stable electrical connection to the cable connector 202, which can maintain the head assembly 200 at an equal potential and solve the problem of head heating. In other embodiments, the first accommodating portion may not have a ring groove therein, and a certain gap may exist between the inner wall of the first accommodating portion and the cable connector, so that the spring contact finger may be pressed between the inner wall of the first accommodating portion and the cable connector, and the spring contact finger may also be maintained in a relatively fixed state.

In this embodiment, the inner wall of the first through hole 2013 is also provided with a ring groove, a sealing ring is disposed in the ring groove, and when the header assembly 200 is installed in the transformer bushing, a seal of the header assembly is added to prevent oil leakage.

In the head assembly 200 of the present embodiment, due to the arrangement of the connection terminal 203, the pin 2021 and the groove 2015 are tightly fixed by the inner wall of the connection terminal 203, and the relative position of the cable connector 202 and the convex ring 2014 is fixed, so that the cable connector 202 does not jump along with the vibration of the transformer bushing, and the head of the transformer bushing does not generate heat due to unstable current; and the pin 2021 is convenient with fixed connection, installation and dismantlement between binding post 203 and the recess 2015 respectively, the installation fortune dimension of being convenient for.

Example three:

as shown in fig. 5-6, the present embodiment is a transformer bushing 1000 including the header assembly 200 described above.

In this embodiment, the transformer bushing 1000 further includes a conductive tube 300, the conductive tube 300 is attached to the inner wall of the first through hole 2013, and the cable connector 202 is inserted into the conductive tube 300 and is not in contact with the conductive tube 300; the cable connector 202 is suspended in the conductive tube 300, and there is no electric conduction and thus no unstable electric connection, and no heat generation at the head of the transformer bushing 1000.

In this embodiment, a sealing groove is formed between the conductive tube 300 and the inner wall of the first through hole 2013 to accommodate a sealing ring, and one sealing is provided to prevent the oil leakage at the head of the bushing of the transformer.

In this embodiment, transformer bushing 1000 further includes oil conservator 400, composite bushing 500, insulating tube in oil 600, and end assembly 700 and capacitor core, head assembly 200 is connected to oil conservator 400, and conductive tube 300 is a portion of the capacitor core.

In other embodiments, the transformer bushing may employ the structure of header assembly 100 described above.

The transformer bushing 1000 of this embodiment is owing to adopt above-mentioned head subassembly 200, and transformer bushing head can not produce the condition that generates heat because of the electric current is unstable, and the installation is convenient with the dismantlement, is convenient for install fortune dimension.

While the invention has been described with reference to the above disclosure and features, it will be understood by those skilled in the art that various changes and modifications in the above constructions and materials can be made, including combinations of features disclosed herein either individually or in any combination, as appropriate, without departing from the spirit of the invention. Such variations and/or combinations are within the skill of the art to which the invention pertains and are within the scope of the following claims.

Claims

1. A header assembly for a transformer bushing, comprising: the head assembly comprises an end cap and a cable connector;

the end cover comprises an upper surface and a lower surface which are opposite, a first through hole is formed in the center of the end cover, a convex ring is arranged on the upper surface and surrounds the first through hole, and at least two grooves are formed in the end surface of the convex ring;

the cable joint penetrates through the first through hole, at least two pin holes are formed in the cable joint, the pin penetrates through the groove and is fixed in the at least two pin holes, and the pin is fixedly connected with the groove, so that the relative position of the cable joint and the convex ring is fixed.

2. The head assembly of claim 1, wherein: the number of the pin holes is two, and the axes of the two pin holes are on the same straight line.

3. The head assembly of claim 2, wherein: the two pin holes are communicated with each other in the cable joint.

4. The head assembly of claim 1, wherein: the recess is U type groove, pin tip is the cylinder.

5. The head assembly of claim 1, wherein: the pin protrudes out of the end face of the convex ring.

6. The head assembly of claim 5, wherein: the head assembly further comprises a wiring terminal, the wiring terminal is fixedly connected with the end cover, and the wiring terminal compresses the pin.

7. The head assembly of claim 6, wherein: binding post includes wiring portion, holding portion and connecting portion, the holding portion is equipped with the echelonment inner wall and has the ladder face, the ladder face butt the bulge loop the terminal surface, connecting portion butt the upper surface.

8. The head assembly of claim 7, wherein: the accommodating part is divided into a first accommodating part and a second accommodating part by taking the stepped surface as a boundary, a spring contact finger is arranged on the cable connector and abuts against the inner wall of the first accommodating part, so that the first accommodating part is electrically connected with the cable connector; the second accommodating part is used for accommodating the convex ring.

9. A transformer bushing, characterized by: comprising a head assembly according to claims 1-8.

10. The transformer bushing of claim 9, wherein: the transformer bushing further comprises a conductive tube, the conductive tube is attached to the inner wall of the first through hole, and the cable connector is inserted into the conductive tube and is not in contact with the conductive tube.