CN221149792U - Transformer sleeve - Google Patents

Abstract

The application discloses a transformer bushing, which comprises a head component, a conducting rod, a composite outer sleeve and a tail component, wherein the conducting rod sequentially penetrates through the head component, the composite outer sleeve and the tail component, the composite outer sleeve comprises an insulating tube and an umbrella cover coated on the outer peripheral surface of the insulating tube, a first flange is sleeved at one end, close to the head component, of the insulating tube, a second flange is sleeved at one end, close to the tail component, of the insulating tube, the umbrella cover comprises a plurality of umbrella skirts which are arranged at intervals along the axial direction of the insulating tube, and the tail component comprises: the insulating tube in oil comprises an insulating cylinder and a second connecting part, the insulating cylinder is in a hollow structure along the axial direction of the insulating cylinder, the second connecting part extends along the radial direction of the insulating cylinder towards the direction away from the insulating cylinder at the periphery of one end of the insulating cylinder, the second connecting part is fixedly connected with a second flange, and one end of the conducting rod, which is positioned at the tail component, protrudes out of the insulating tube in oil; and the shielding electrode is positioned between the conducting rod and the second flange.

Description

Transformer sleeve

Technical Field

The application relates to the field of power transmission insulation equipment, in particular to a transformer bushing.

Background

The existing low-voltage oil-filled bushing generally adopts a porcelain insulator as an external insulation structure, the porcelain insulator belongs to a brittle material, and explosion of the porcelain insulator is easy to occur when a transformer has faults such as overvoltage, lightning stroke and the like, so that secondary damage to surrounding personnel, equipment and the like is caused; meanwhile, the porcelain insulator belongs to a hydrophilic material, and the problem of external insulation flashover is easy to occur in rainy and foggy days; and the porcelain insulator is formed by sintering bauxite, the bauxite belongs to non-renewable resources, and serious environmental pollution and damage problems exist in the exploitation process.

Disclosure of utility model

Aiming at the defects of the prior art, the application aims to provide a transformer bushing so as to solve the problems that the existing low-voltage oil-filled transformer bushing is easy to explode, crack, and flashover due to external insulation.

In order to achieve the above purpose, the technical means adopted by the application are as follows: the utility model provides a transformer bushing, including head subassembly, conducting rod, compound overcoat and afterbody subassembly, the conducting rod wears to establish head subassembly, compound overcoat and afterbody subassembly in proper order, and compound overcoat includes the insulating tube and coats in the chute boot of insulating tube outer peripheral face, and the insulating tube is close to the one end cover of head subassembly and is equipped with first flange, and the insulating tube is close to the one end cover of afterbody subassembly and is equipped with the second flange, and the chute boot includes a plurality of chute skirts that set up along the axial interval of insulating tube, and the afterbody subassembly includes: the insulating tube in oil comprises an insulating cylinder and a second connecting part, the insulating cylinder is in a hollow structure along the axial direction of the insulating cylinder, the second connecting part extends along the radial direction of the insulating cylinder towards the direction away from the insulating cylinder at the periphery of one end of the insulating cylinder, the second connecting part is fixedly connected with a second flange, and one end of the conducting rod, which is positioned at the tail component, protrudes out of the insulating tube in oil; and the shielding electrode is positioned between the conducting rod and the second flange.

Preferably, the second flange comprises a second flange cylinder and a second flange plate, the second flange cylinder is of a hollow structure along the axial direction of the second flange cylinder, the second flange plate covers the end part of the second flange cylinder, which is far away from the insulating pipe, the second flange plate is a hollow flange plate, the inner diameter of the second flange plate is smaller than the inner diameter of the insulating pipe, the outer diameter of the second flange plate is larger than the outer diameter of the second flange cylinder, and the second flange plate is fixedly connected with the second connecting part.

Preferably, the shielding electrode comprises a sleeve part and a third connecting part, the sleeve part is of a hollow structure along the axial direction of the sleeve part, the third connecting part extends along the radial direction of the sleeve part in the direction away from the sleeve part on the outer peripheral surface of the sleeve part, the sleeve part comprises a first sleeve part and a second sleeve part which are positioned on two sides of the third connecting part, the third connecting part is fixedly connected between the second flange plate and the second connecting part, and the first sleeve part is positioned in the insulating tube, and the second sleeve part is positioned in the insulating tube in oil.

Preferably, the third connecting portion, the second flange plate and the second connecting portion are fixedly connected through a fastener, in the axial direction of the sleeve portion, one end of the first sleeve portion, which is far away from the third connecting portion, is flush with the root of the umbrella skirt closest to the second flange on the umbrella cover, and one end of the second sleeve portion, which is far away from the third connecting portion, is slightly lower than the end of the fastener.

Preferably, a cavity is formed between the outer peripheral surface of the first sleeve part and the inner wall of the insulating tube, a plurality of oil holes are formed in the first sleeve part, at least one oil hole is communicated with the end surface of the second flange, which is abutted against the insulating tube, and the oil holes are located at the lowest end of the cavity.

Preferably, the shielding electrode is made of carbon fiber material, the shielding electrode is arranged on the outer peripheral surface of the insulating tube, and the shielding electrode comprises a plurality of layers of carbon fiber felt.

Preferably, the outer peripheral surface of the insulating tube connected with the second flange is provided with glue grooves which are axially arranged at intervals along the insulating tube, the depth of each glue groove is slightly smaller than the thickness of the shielding electrode, and carbon fiber felts are arranged in the glue grooves in a coating mode.

Preferably, the tail assembly further comprises a half ring, the half ring is arranged in the oil insulating tube, the half ring comprises two semicircular rings, and the two semicircular rings are connected with each other on the outer circumferential surface of the conducting rod.

Preferably, the conducting rod is provided with a concave part, the concave part is arranged on the outer peripheral surface of the conducting rod, which is positioned in the shielding electrode, and the concave part is an annular groove.

Preferably, a gap is left between the half ring and the insulating tube in the oil.

The beneficial effects of the application are as follows: the transformer bushing comprises the head component, the conducting rod, the composite jacket and the tail component, wherein the conducting rod sequentially penetrates through the head component, the composite jacket and the tail component, a shielding electrode is arranged between the conducting rod and the inner wall of the insulating tube, and the shielding electrode is positioned between the conducting rod and the second flange, so that a discharge path caused by defects such as bubbles generated at the gluing position of the second flange and the insulating tube can be shielded, the field intensity at the second flange is uniform, and partial discharge is prevented. Meanwhile, the head assembly is provided with the pressing piece and the end cover, so that the connection between all parts of the transformer sleeve is firmer, and deflection is not easy to occur. In conclusion, the transformer bushing is not easy to cause the problems of explosion, brittle fracture, external insulation flashover, partial discharge and the like, and ensures the stable and safe operation of the transformer bushing.

Drawings

FIG. 1 is a schematic cross-sectional view of a transformer bushing according to an embodiment of the present application;

FIG. 2 is an enlarged schematic view at A in FIG. 1;

FIG. 3 is a schematic cross-sectional view of a first flange 130 according to an embodiment of the present application;

Fig. 4 is a schematic plan view of a first platen 211 according to an embodiment of the present application;

Fig. 5 is a top view of the first flange 130 of fig. 3;

fig. 6 is an enlarged schematic view at B in fig. 1.

Detailed Description

As required, specific embodiments of the present application will be disclosed herein. However, it is to be understood that the embodiments disclosed herein are merely exemplary of the application, 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 application in virtually any appropriately manner, including employing the various features disclosed herein in connection with features that may not be explicitly disclosed.

Referring to fig. 1, a transformer bushing 100 of the present application is disposed on a transformer (not shown), and is particularly connected to leads of a transformer winding, and the transformer bushing 100 is used for guiding current in the transformer to an external conductor such as a cable or guiding current in the external conductor such as a cable to the transformer, and simultaneously providing a space insulation distance between an external high voltage cable and a transformer housing and mechanically supporting the external high voltage cable.

The transformer bushing 100 includes a header assembly 200, a conductive rod 110, a composite jacket 120, and a tail assembly 300, wherein the conductive rod 110 sequentially passes through the header assembly 200, the composite jacket 120, and the tail assembly 300, the conductive rod 110 is located at a first end 111 of the header assembly 200, and the conductive rod 110 is located at a second end 115 of the tail assembly 300.

The composite jacket 120 comprises an insulating tube 121 and an umbrella cover 122 coated on the outer circumferential surface of the insulating tube 121, and the insulating tube 121 is axially arranged to be of a hollow structure, namely a hollow insulating tube. The insulating tube 121 is made of glass fiber reinforced plastic, has good mechanical strength and toughness, and does not explode even in extreme cases where the pressure inside the insulating tube 121 is too great. The umbrella cover 122 is integrally injection molded by high-temperature vulcanized silicone rubber, which has good hydrophobicity and hydrophobic migration, and excellent pollution flashover resistance, rain flashover resistance and ice flashover resistance. The umbrella cover 122 includes a plurality of umbrella skirts 123 spaced apart along the axial direction of the insulating tube 121.

Referring to fig. 1 to 3, a first flange 130 is sleeved at one end of the insulating tube 121 near the head assembly 200, the first flange 130 includes a first flange cylinder 131 and a first flange plate 132, the first flange cylinder 131 is in a hollow structure along an axial direction thereof, the first flange plate 132 covers an end portion of the first flange cylinder 131 far away from the insulating tube 121, and an outer edge of the first flange plate 132 is flush with an outer peripheral surface of the first flange cylinder 131, so that the first flange 130 is in a cup-shaped structure integrally, and the first flange cylinder 131 and the first flange plate 132 are integrally formed, so that the integral structure of the first flange 130 is more stable. Of course, the first flange cylinder and the first flange plate may also be fixed by welding or mechanical connection, without limitation. The first flange 130 is fixedly connected with the insulating tube 121 in a gluing mode, the first flange cylinder 131 is glued on the periphery of the insulating tube 121, and the first flange 132 seals the end part of the insulating tube 121 to prevent water vapor, impurities and the like from entering the insulating tube 121.

The first flange 132 is provided with a first through hole 133 penetrating along the axial direction thereof, the conductive rod 110 is fixed on the first flange 130 through the first through hole 133, and the inner diameter of the first through hole 133 is matched with the outer diameter of the conductive rod 110. The first through hole 133 is located at the center of the first flange 132, so that the conductive rod 110 can be ensured to be located at the center of the composite jacket 120. Meanwhile, the outer peripheral surface of the conductive rod 110 is provided with a protruding portion 112 extending outwards along the radial direction of the conductive rod 110, after the conductive rod 110 penetrates through the head assembly 200, the protruding portion 112 is located at the position of the head assembly 200, the outer diameter of the protruding portion 112 is larger than that of the conductive rod 110, the protruding portion 112 and the outer peripheral surface of the conductive rod 110 form a step, after the conductive rod 110 penetrates through the first through hole 133, the step enables the conductive rod 110 to be clamped and fixed on the first flange 130, the protruding portion 112 abuts against the end face of the first flange 132, which is close to one side of the insulating tube 121, and the end face of the protruding portion 112 abutting against the first flange 132 is a first step face 1121. The terminal surface of first flange 132 butt first step face 1121 is equipped with first sealing portion 134, first sealing portion 134 is the annular inclined plane of setting on first through-hole 133 inner wall, after conducting rod 110 wears to establish first through-hole 133, form annular seal groove between this annular inclined plane and the outer peripheral face of first step face 1121, conducting rod 110, set up first sealing washer in this annular seal groove, and then first sealing washer is located between first step face 1121 and the first flange 132, make conducting rod 110 and first flange 130 sealing connection, prevent that transformer oil in the insulating tube 121 from overflowing from the junction of conducting rod 110 and first flange 130.

The outer side surface of the first flange 132, which is flush with the first flange barrel 131, is provided with at least one air release hole 1311, the axis of the air release hole 1311 is parallel to the disk surface of the first flange 132, the air release hole 1311 is a threaded hole, and meanwhile, a step is further arranged in the air release hole 1311 and used for installing an oil plug, the oil plug comprises a fixing part provided with external threads, and the fixing part is fixed with the air release hole 1311 through threaded connection. The end surface of the first flange 132 near the insulating tube 121 is vertically provided with a communication hole 1321, and the communication hole 1321 is arranged near the air release hole 1311 and is communicated with the air release hole 1311, so that the inside and outside of the insulating tube 121 are communicated, and the air pressure inside and outside the insulating tube 121 is equal. Meanwhile, the transformer oil filled in the insulating tube 121 is used for insulating on one hand, improving the insulating strength inside the transformer bushing 100, and on the other hand, also can be used for radiating heat, so that the damage caused by the overhigh temperature of the insulating tube 121 is avoided, and the air in the insulating tube 121 can be discharged out of the insulating tube 121 into the external environment when the transformer bushing 100 is filled with oil or discharged with oil due to the arrangement of the air vent 1311. And when the transformer bushing 100 completes the oil injection, the oil plug is fastened in the air release hole 1311, so as to prevent external water vapor, impurities and the like from entering the insulating tube 121. A sealing member is further arranged between the oil plug and the air release hole 1311, so that the oil plug is sealed and fixed in the air release hole 1311, and external water vapor, impurities and the like are further prevented from entering the insulating tube 121.

With continued reference to fig. 1 to 5, the head assembly 200 includes a pressing member 210 and an end cap 220, the conductive rod 110 is disposed in the hollow of the insulating tube 121 in a penetrating manner, the first end 111 of the conductive rod 110 protrudes out of the first flange 130 after passing through the first through hole 133, the pressing member 210 is sleeved on the outer periphery of the conductive rod 110 protruding out of the first flange 130 and abuts against the first flange 130, and the end cap 220 is sleeved on the outer periphery of the pressing member 210 and abuts against the first flange 130. Meanwhile, the first end 111 of the conductive rod 110 protrudes out of the end cap 220 for connecting the connection terminal 101. The pressing piece 210 comprises a first pressing plate 211, a round nut 212 and a second pressing plate 213 which are sequentially sleeved on the periphery of the conductive rod 110, and the first pressing plate 211 abuts against the first flange 130.

Specifically, the end surface of the first flange 132 far away from the insulating tube 121 is provided with a first groove 135, the first groove 135 is an annular groove disposed on the inner wall of the first through hole 133 and extending along the radial direction of the first flange 132 towards the direction far away from the first through hole 133, that is, the first groove 135 and the first through hole 133 are coaxially disposed, and the diameter of the first groove 135 is larger than that of the first through hole 133, so that a second step surface 1351 is formed between the first groove 135 and the first through hole 133, and the diameter of the first groove 135 is matched with the outer diameter of the first pressing plate 211, the first pressing plate 211 is disposed in the first groove 135 after being sleeved on the outer circumferential surface of the conductive rod 110, and meanwhile the first pressing plate 211 abuts against the second step surface 1351. Further, the second step surface 1351 is provided with a second sealing portion 136, the second sealing portion 136 is an annular inclined surface disposed on the inner wall of the first groove 135, when the first pressing plate 211 abuts against the second step surface 1351, an annular sealing groove is formed between the annular inclined surface and the outer peripheral surfaces of the first pressing plate 211 and the conductive rod 110, and a second sealing ring is disposed in the annular sealing groove, and further the second sealing ring is located between the second step surface 1351 and the first pressing plate 211, so that the first pressing plate 211 and the first flange 130 are sealed and fixed. Of course, the second sealing portion may not be provided on the second step surface, and the first pressing plate may directly abut against the second step surface.

Referring to fig. 2 and 4, the first pressing plate 211 is an annular plate, a second through hole 2111 is formed in the center of the first pressing plate 211, the first pressing plate 211 is sleeved on the periphery of the conductive rod 110 through the second through hole 2111, two first clamping grooves 2112 are symmetrically formed in an annular plate surface, far from the insulating tube 121, of the first pressing plate 211 along the diameter of the annular plate surface, and the central lines of the two first clamping grooves 2112 are located on the same diameter of the first pressing plate 211. The position where the first pressing plate 211 is sleeved on the conducting rod 110 is provided with a third through hole 116 penetrating through the conducting rod 110 in the radial direction, and the third through hole 116 is a kidney-shaped hole, so that the installation of a pin (not shown) is facilitated. The first pressing plate 211 is sleeved on the periphery of the conductive rod 110, the third through hole 116 is correspondingly matched with the first clamping groove 2112, one first clamping groove 2112, the third through hole 116 and the other first clamping groove 2112 are sequentially penetrated through by a pin, the first pressing plate 211 is fixedly sleeved on the periphery of the conductive rod 110, and two ends of the pin are protruded out of the periphery of the conductive rod 110. Meanwhile, referring to fig. 5, two second clamping grooves 137 are symmetrically arranged on the inner wall of the first groove 135 along the diameter of the first groove, the central lines of the two second clamping grooves 137 are located on the same diameter of the first flange cylinder 131, the second clamping grooves 137 extend for a certain distance along the radial direction of the first flange cylinder 131 towards the direction close to the outer peripheral surface of the first flange cylinder 131, during installation, the second clamping grooves 137, the first clamping grooves 2112 and the third through holes 116 are coaxially arranged, so that production staff can conveniently pass through pins, after the pins pass through the third through holes 116 and the first clamping grooves 2112 in sequence, two ends of the pins protruding out of the conducting rod 110 are clamped in the two second clamping grooves 137, and deflection of the conducting rod 110 in the operation of a transformer can be prevented.

The conducting rod 110 stretches out the outer peripheral face of first recess 135 and still is equipped with the external screw thread, round nut 212 is equipped with the internal screw thread, round nut 212 establishes at conducting rod 110 periphery and the annular face that insulating tube 121 was kept away from to first clamp plate 211 of butt through screw-thread fit fastening cover, simultaneously through screwing round nut 212, makes first clamp plate 211 and first flange 130 closely laminate fixedly, the setting of first sealing washer and second sealing washer can prevent outside steam, impurity etc. entering insulating tube 121 in, round nut 212 also butt compresses tightly the pin simultaneously, prevents that the pin from taking place the drunkenness. The second pressing plate 213 is also an annular plate, a fourth through hole is arranged in the center of the second pressing plate 213, the second pressing plate 213 is sleeved on the periphery of the conductive rod 110 through the fourth through hole, and the second pressing plate 213 abuts against the end face of the round nut 212, which is far away from the first pressing plate 211.

The end cap 220 includes a receiving portion 221 and a first connection portion 222, the receiving portion 221 having a cup-shaped structure, and the first connection portion 222 extends in a direction away from the receiving portion 221 in a radial direction of the receiving portion 221 near an outer circumferential surface of the first flange 130. The cup-shaped bottom surface of the accommodating part 221 is provided with a through fifth through hole along the axial direction thereof, the end cover 220 is sleeved on the periphery of the conductive rod 110 through the fifth through hole, the cup-shaped cavity of the accommodating part 221 is arranged around the fifth through hole to accommodate the second pressing plate 213 and the round nut 212, the cup-shaped bottom surface of the accommodating part 221 is abutted against the end surface of the second pressing plate 213 far away from the round nut 212, and meanwhile, the first connecting part 222 is abutted against the first flange 132 far away from the disc surface of the insulating tube 121, so that the second pressing plate 213 and the round nut 212 are completely accommodated and pressed in the cup-shaped inner cavity of the end cover 220. The end face, far away from the insulating tube 121, of the first flange 132 is provided with a plurality of first mounting holes 1323 uniformly distributed along the circumferential direction, the first mounting holes 1323 are threaded holes, the first connecting portion 222 is provided with a plurality of second mounting holes 2221 uniformly distributed along the circumferential direction and correspondingly matched with the first mounting holes 1323, and the second mounting holes 2221 are through holes. The first mounting hole 1323 and the second mounting hole 2221 are correspondingly matched and then are penetrated by fasteners, so that the end cover 220 is fixedly connected with the first flange 130.

Further, the end surface of the second pressing plate 213 abutting against the accommodating portion 221 is provided with a third sealing portion 2131, the third sealing portion 2131 is an annular inclined surface provided on the inner wall of the fourth through hole, an annular sealing groove is formed between the third sealing portion 2131 and the inner end surface of the accommodating portion 221 and the outer circumferential surface of the conductive rod 110, and a third sealing ring is provided in the annular sealing groove, so that the pressing member 210 is in sealing connection with the end cover 220 and the conductive rod 110. The end surface of the first flange 132 abutting against the first connecting portion 222 is provided with a fourth sealing portion 1322, the fourth sealing portion 1322 is an annular groove and is coaxially arranged with the first groove 135, and a fourth sealing ring is arranged in the fourth sealing portion 1322, so that the end cover 220 is in sealing connection with the first flange 130.

Referring to fig. 1 and 6, a second flange 140 is sleeved at one end of the insulating tube 121 near the tail assembly 300, the second flange 140 includes a second flange plate 143 and a second flange cylinder 144, the second flange cylinder 144 is in a hollow structure along the axial direction of the second flange cylinder 144, the second flange plate 143 covers the end part of the second flange cylinder 144 far away from the insulating tube 121, the second flange plate 143 is a hollow flange plate, the inner diameter of the second flange plate 143 is smaller than the inner diameter of the insulating tube 121, and the outer diameter of the second flange plate 143 is larger than the outer diameter of the second flange cylinder 144. The second flange 143 and the second flange cylinder 144 are integrally formed, the second flange 140 is sleeved at the end part of the insulating tube 121 in a gluing mode, wherein the second flange cylinder 144 is glued on the periphery of the insulating tube 121, and the second flange 143 abuts against the end face of the insulating tube 121. The center of the second flange 143 is provided with a sixth through hole, so that the second flange 143 is a hollow flange for penetrating the conductive rod 110, and since the inner diameter of the second flange 143 is smaller than the inner diameter of the insulating tube 121, the end surface of the insulating tube 121 is completely abutted against the second flange 143, and meanwhile, in the radial direction of the second flange 143, the inner surface of the second flange 143 is spaced from the inner surface of the insulating tube 121 by a certain distance. The second flange 143 is provided with a plurality of third mounting holes 141 uniformly distributed along the circumferential direction for fixedly connecting with the transformer. The outermost edge of the second flange 143 is further provided with a second groove for reducing the thickness of the second flange 143 and reducing the weight and material cost of the second flange 140.

The tail assembly 300 includes an insulation tube 310 in oil and a huff ring 320. The insulating tube 310 in oil includes an insulating cylinder 311 and a second connecting portion 312, the insulating cylinder 311 is hollow along an axial direction thereof, the second connecting portion 312 extends along a radial direction of the insulating cylinder 311 in a direction away from the insulating cylinder 311 on an outer peripheral surface of one end of the insulating cylinder 311, a plurality of fourth mounting holes 313 uniformly distributed along a circumferential direction are formed in the second connecting portion 312, and the fourth mounting holes 313 are through holes. The second flange 143 is also provided with a plurality of fifth mounting holes 142 which are uniformly distributed along the circumferential direction and correspondingly matched with the fourth mounting holes 313, and the fifth mounting holes 142 are threaded holes. The fourth mounting holes 313 and the fifth mounting holes 142 are matched one by one, and then fasteners are penetrated, so that the second connecting part 312 is mounted on the second flange 143, the insulating tube 310 in oil is fixedly connected with the second flange 140, the second end 115 of the conducting rod 110 extends out of the insulating tube 310 in oil and is used for being connected with a lead wire of a transformer winding, and the insulating tube 310 in oil is made of polytetrafluoroethylene or glass fiber reinforced plastic material. The provision of the insulating tube 310 in oil can increase the insulation distance of the transformer bushing 100.

The tail assembly 300 further includes a shielding electrode 150, the shielding electrode 150 being positioned between the conductive rod 110 and the second flange 140 for uniform electric field. The shielding electrode 150 can shield the discharge path caused by the defects of bubbles and the like generated at the glue binding position of the second flange 140 and the insulating tube 121, and even the field intensity at the second flange 140, thereby preventing the occurrence of partial discharge and ensuring the stable and safe operation of the transformer bushing 100.

In an embodiment, the shielding electrode 150 is a metal piece made of metal material such as aluminum or copper, the shielding electrode 150 includes a sleeve portion 151 and a third connection portion 152, the sleeve portion 151 is in a hollow structure along an axial direction thereof, the third connection portion 152 extends along a radial direction of the sleeve portion 151 along an outer peripheral surface of the sleeve portion 151 in a direction away from the sleeve portion 151, a plurality of sixth mounting holes 153 uniformly distributed along a circumferential direction are provided on the third connection portion 152, and the sixth mounting holes 153 are through holes. The portions of the sleeve portion 151 located at two sides of the third connection portion 152 are respectively defined as a first sleeve portion 1511 and a second sleeve portion 1512, that is, the sleeve portion 151 includes the first sleeve portion 1511 and the second sleeve portion 1512, the outer diameter of the first sleeve portion 1511 is matched with the diameter of the sixth through hole on the second flange 143, so that the first sleeve portion 1511 can be inserted into the insulating tube 121 after penetrating through the sixth through hole, meanwhile, the third connection portion 152 is clamped and fixed on the second flange 143, the outer diameter of the second sleeve portion 1512 is matched with the inner diameter of the insulating tube 310 in oil, so that the second sleeve portion 1512 is clamped on the insulating tube 310 in oil, that is, the sleeve portion 151 is coaxially arranged with the insulating tube 121 and the insulating tube 310 in oil, the third connection portion 152 is mounted between the second flange 143 and the second connection portion 312, and the sixth mounting hole 153 is correspondingly matched with the fourth mounting hole 313 and the fifth mounting hole 142, and then fasteners are penetrated, so that the insulating tube 310 in oil, the shielding electrode 150 and the second flange 140 are sequentially fastened and connected. The sleeve portion 151 and the third connecting portion 152 are integrally formed.

Further, in the axial direction of the sleeve portion 151, an end of the first sleeve portion 1511 away from the third connecting portion 152 is flush with a root of the umbrella skirt 123 closest to the second flange 140 on the umbrella cover 122, and in the direction of fig. 1, an end of the second sleeve portion 1512 away from the third connecting portion 152 is slightly lower than the fastening pieces fixed in the sixth mounting hole 153, the fourth mounting hole 313 and the fifth mounting hole 142, so that the tips of the fastening pieces are prevented from causing uneven electric field in the tail assembly 300.

The first sleeve portion 1511 is provided with a plurality of oil holes for facilitating the transformer oil to enter the insulating tube 121. Since the inner diameter of the second flange 143 is smaller than the inner diameter of the insulating tube 121, after the first sleeve portion 1511 is clamped on the second flange 143, a cavity 154 is formed between the outer circumferential surface of the first sleeve portion 1511 and the inner wall of the insulating tube 121, so as to prevent the field intensity on the insulating tube 121 from exceeding the allowable value. In this embodiment, the oil through holes include a terminal oil through hole 155 and a middle oil through hole 156, where the terminal oil through hole 155 is communicated with the end surface of the second flange 143 and abuts against the insulating tube 121, so that the terminal oil through hole 155 is located at the lowest end of the cavity 154, transformer oil can enter the cavity 154 from the terminal oil through hole 155 during oil filling, and then can quickly fill the inner cavity of the insulating tube 121, and transformer oil in the cavity 154 can be ensured to be completely discharged during oil discharging. The middle oil hole 156 is located on any outer circumferential surface of the first sleeve portion 1511 connecting cavity 154, and can accelerate the oil filling and discharging speed, which is not limited herein. In another embodiment, only one oil passing hole may be provided, which is the terminal oil passing hole 155. The arrangement of the oil through holes ensures that the cavity 154 is filled with transformer oil quickly when the insulating tube 121 is filled with oil, and ensures that no bubbles exist in the cavity 154, and ensures that the transformer oil in the cavity 154 is discharged completely when the insulating tube 121 is discharged with oil.

In another embodiment, the shielding electrode is made of carbon fiber material, after the preparation of the insulating tube is completed, a plurality of layers of carbon fiber felts are wound at the position where the second flange is sleeved on the outer wall of the insulating tube to form the shielding electrode, one end of the shielding electrode is flush with the root of the umbrella skirt closest to the second flange on the umbrella cover in the axial direction of the insulating tube, and the other end of the shielding electrode is flush with the end of the insulating tube close to the second flange, so as to shield partial discharge caused by glue solution bubbles generated in the gluing process of the insulating tube and the second flange. Specifically, a plurality of glue grooves are formed in the positions of the insulating tube and the second flange in a glue-binding mode at intervals along the axial direction of the insulating tube, the radial height of the glue grooves along the insulating tube is defined to be the depth of the glue grooves, the radial height of the shielding electrode along the insulating tube is defined to be the thickness of the shielding electrode, the depth of the glue grooves is slightly smaller than the thickness of the shielding electrode, for example, when the depth of the glue grooves is set to be 1mm, the thickness of the shielding electrode can be set to be 1.5mm, 2mm or other thicknesses, only the situation that carbon fiber felts are still coated in the glue grooves to form the shielding electrode can be guaranteed, disconnection of a conductive channel of the shielding electrode can be avoided, contact between the shielding electrode and the second flange is guaranteed, grounding of the shielding electrode is achieved, namely, partial discharge caused by defects such as bubbles generated in a glue-binding area can be effectively shielded, and field intensity of the second flange is uniform.

In other embodiments, the shielding electrode may be made of other conductive materials, so long as the partial discharge of the transformer bushing is prevented, which is not limited herein.

The conducting rod 110 is further sleeved with a half ring 320 at the periphery of the tail assembly 300, and the half ring 320 is arranged in the insulating tube 310 in oil. The half ring 320 includes two semicircular rings, and the two semicircular rings are connected in a matched manner, such as joggling, mechanical fixing or other manners. The half ring 320 is provided with a seventh mounting hole 321, the conducting rod 110 is provided with an eighth mounting hole 114 correspondingly matched with the seventh mounting hole 321, the seventh mounting hole 321 is a through hole, the eighth mounting hole 114 is a threaded hole, and a screw sequentially penetrates through the seventh mounting hole 321 and the eighth mounting hole 114 to fixedly connect the half ring 320 with the conducting rod 110. The half ring 320 is used to fix the conductive rod 110 at the tail of the transformer bushing 100, and prevent the conductive rod 110 from being deviated in the transformer bushing 100. In other embodiments, the half ring may be mounted on the conductive rod in other manners, so long as the conductive rod is prevented from being deviated, which is not limited herein. A gap is left between the half ring 320 and the oil insulating tube 310, and the width of the gap is set to be greater than 0 and less than 2mm. In this embodiment, the gap is 1mm, so that transformer oil can enter the insulating tube 121 through the gap, and the conductive rod 110 is not easily biased.

In an application scenario, the conducting rod 110 is provided with the concave part 113, the concave part 113 is arranged on the outer peripheral surface of the conducting rod 110 inside the shielding electrode 150, the concave part 113 is an annular groove, and the arrangement of the concave part 113 can increase the electric gap between the outer wall of the conducting rod 110 and the shielding electrode 150, so that the field intensity of the transformer sleeve 100 is reduced, and the stable and safe operation of the transformer sleeve 100 is ensured. Meanwhile, after the electrical gap between the outer wall of the conductive rod 110 and the shielding electrode 150 is ensured to meet the requirements, the size of the shielding electrode 150 may be set to be more compact, i.e., the inner diameter of the shielding electrode 150 may be set to be minimum, and thus the size of the composite jacket 120 may be set to be minimum, thereby reducing the manufacturing cost of the transformer bushing 100.

The transformer bushing comprises a head assembly, a conductive rod, a composite outer sleeve and a tail assembly, wherein the conductive rod sequentially penetrates through the head assembly, the composite outer sleeve and the tail assembly, a shielding electrode is arranged between the conductive rod and the inner wall of an insulating tube, and the shielding electrode is positioned between the end part of the insulating tube, which is close to a second flange, and the root part of the umbrella skirt, closest to the second flange, of a plurality of umbrella skirts. The transformer bushing is not easy to explode, crack, and flashover. The shielding electrode is arranged, so that the problem of partial discharge of the transformer bushing can be avoided, and the stable and safe operation of the transformer bushing is ensured.

While the present disclosure and features have been described above with respect to specific embodiments, it will be appreciated that those skilled in the art, upon attaining the teachings of the present disclosure, may readily devise numerous variations and modifications of the above-described structures and materials, including combinations of features that are individually disclosed or claimed herein, and obviously other combinations of such features. Such variations and/or combinations fall within the technical field to which the application relates and fall within the scope of the claims of the application.

Claims (10)

1. The utility model provides a transformer bushing, its characterized in that, transformer bushing includes head subassembly, conducting rod, compound overcoat and afterbody subassembly, the conducting rod wears to establish in proper order head subassembly compound overcoat with the afterbody subassembly, compound overcoat include the insulating tube with the cladding in insulating tube outer peripheral face's chute boot, the insulating tube be close to head subassembly's one end cover is equipped with first flange, the insulating tube is close to afterbody subassembly's one end cover is equipped with the second flange, the chute boot includes a plurality of edges that follow the axial interval of insulating tube set up, the afterbody subassembly includes:

The insulating tube in oil comprises an insulating cylinder and a second connecting part, the insulating cylinder is in a hollow structure along the axial direction of the insulating cylinder, the second connecting part extends along the radial direction of the insulating cylinder towards the direction far away from the insulating cylinder at the periphery of one end of the insulating cylinder, the second connecting part is fixedly connected with the second flange, and one end of the conducting rod, which is positioned at the tail assembly, protrudes out of the insulating tube in oil;

and a shielding electrode positioned between the conductive rod and the second flange.

2. The transformer bushing according to claim 1, wherein the second flange comprises a second flange cylinder and a second flange plate, the second flange cylinder is of a hollow structure along an axial direction of the second flange cylinder, the second flange plate covers an end portion of the second flange cylinder, which is far away from the insulating tube, the second flange plate is a hollow flange plate, an inner diameter of the second flange plate is smaller than an inner diameter of the insulating tube, an outer diameter of the second flange plate is larger than an outer diameter of the second flange cylinder, and the second flange plate is fixedly connected with the second connecting portion.

3. The transformer bushing according to claim 2, wherein the shield electrode comprises a sleeve portion and a third connecting portion, the sleeve portion is hollow along an axial direction thereof, the third connecting portion extends along a radial direction of the sleeve portion along an outer peripheral surface of the sleeve portion in a direction away from the sleeve portion, the sleeve portion comprises a first sleeve portion and a second sleeve portion located at both sides of the third connecting portion, and the third connecting portion is fixedly connected between the second flange plate and the second connecting portion, so that the first sleeve portion is located in the insulating tube and the second sleeve portion is located in the insulating tube in oil.

4. A transformer bushing according to claim 3, wherein the third connecting portion, the second flange plate and the second connecting portion are fixedly connected by a fastener, and in the axial direction of the sleeve portion, an end of the first sleeve portion, which is far away from the third connecting portion, is flush with the umbrella skirt root portion of the umbrella cover, which is closest to the second flange, and an end of the second sleeve portion, which is far away from the third connecting portion, is slightly lower than an end of the fastener.

5. A transformer bushing according to claim 3, wherein a cavity is formed between the outer peripheral surface of the first sleeve portion and the inner wall of the insulating tube, a plurality of oil through holes are formed in the first sleeve portion, at least one oil through hole is communicated with the end face of the second flange abutting against the insulating tube, and the oil through holes are located at the lowest end of the cavity.

6. The transformer bushing of claim 1, wherein the shielding electrode is a carbon fiber material, the shielding electrode is disposed on an outer circumferential surface of the insulating tube, and the shielding electrode comprises a plurality of carbon fiber mats.

7. The transformer bushing according to claim 6, wherein a glue groove is formed in an outer circumferential surface of the insulating tube connected with the second flange at intervals along the axis of the insulating tube, the depth of the glue groove is slightly smaller than the thickness of the shielding electrode, and the carbon fiber felt is arranged in the glue groove in a coating mode.

8. The transformer bushing of claim 1, wherein the tail assembly further comprises a half ring disposed within the oil insulating tube, the half ring comprising two semicircular rings, the two semicircular rings being interconnected on the outer circumferential surface of the conductive rod.

9. The transformer bushing according to claim 1, wherein the conductive rod is provided with a recess, the recess is formed in an outer circumferential surface of the conductive rod located inside the shielding electrode, and the recess is an annular groove.

10. The transformer bushing of claim 8, wherein a gap is left between the huff ring and the oil insulating tube.