Transformer bushing head assembly and transformer bushing

Abstract

The present application discloses a transformer bushing head assembly and a transformer bushing, the head assembly comprising: an oil pillow, comprising a cover body, the cover body comprising an opposite outer surface and an inner surface, the cover body being provided with a first through hole and a second through hole, the first through hole penetrating the outer surface and the inner surface, the second through hole penetrating the outer surface and the hole wall of the first through hole; a conductive tube, one end of the conductive tube being located in the first through hole; a conductive connector being located in the second through hole, one end of the conductive connector being in contact with the conductive tube in the first through hole, so that the cover body is electrically connected to the conductive tube. In the above manner, the present application can keep the conductive tube and the cover body at the same potential.

Description

Technical Field

[0001] The present application relates to the technical field of transformers, and in particular to a transformer bushing head assembly and a transformer bushing. Background Art

[0002] The transformer bushing is the main insulating device outside the transformer box. It is mainly used to lead out or lead in the current of the transformer winding, and plays the role of insulating and fixing the lead-out or lead-in wires of the transformer winding.

[0003] The inventors of the present application have discovered during long-term research that the current transformer bushing head assembly generally includes a conductive tube and a cover body, which are connected by tolerance matching at the axial seal. The connection between the two is unreliable and poor contact is prone to occur, resulting in a voltage difference between the conductive tube and the cover body, and further causing problems such as local discharge, dielectric loss and abnormal capacitance. Summary of the invention

[0004] The purpose of the present application is to provide a transformer bushing head assembly and a transformer bushing, which can keep the conductive tube and the cover body at the same potential.

[0005] To achieve the above-mentioned purpose, a technical solution adopted in the present application is: to provide a transformer bushing head assembly, the head assembly comprising: an oil pillow, comprising a cover body, the cover body comprising a relative outer surface and an inner surface, the cover body being provided with a first through hole and a second through hole, the first through hole penetrating the outer surface and the inner surface, the second through hole penetrating the outer surface and the hole wall of the first through hole; a conductive tube, one end of the conductive tube being located in the first through hole; a conductive connecting piece, located in the second through hole, one end of the conductive connecting piece abutting against the conductive tube in the first through hole, so that the cover body is electrically connected to the conductive tube.

[0006] Wherein, the conductive connecting member includes a screw, the screw is provided with an external thread, and the inner wall of the second through hole is provided with an internal thread matching the external thread.

[0007] Wherein, it also includes a conductive elastic member, and two ends of the conductive elastic member are respectively abutted against the conductive connecting member and the conductive tube.

[0008] The diameter of the screw at one end adjacent to the conductive tube is smaller than the diameter at the end away from the conductive tube, so as to form a step on the outer wall of the screw; the conductive elastic member includes a spring, one end of which abuts against the conductive tube, and the other end of the spring is sleeved on the end of the screw adjacent to the conductive tube and abuts against the step of the screw.

[0009] Wherein, the cover body, the conductive tube, the conductive connecting piece, and the conductive elastic piece are formed of metal materials.

[0010] Wherein, the cover body forms a convex ring axially away from the cover body at the edge of the first through hole; the second through hole penetrates the outer wall and the inner wall of the convex ring.

[0011] There are multiple second through holes, which are arranged on the convex ring or at the connection between the convex ring and the cover body.

[0012] Wherein, the included angle between the axis of the second through hole and the axis of the first through hole is between 0 and 180 degrees.

[0013] Among them, the conductive tube is a hollow structure, and the head assembly also includes: a current-carrying rod, which is inserted into the conductive tube, the current-carrying rod is passed through the first through hole, and the current-carrying rod does not contact the inner wall of the conductive tube; a positioning pin, which crosses the current-carrying rod, and the two ends of the positioning pin are relatively fixed to the position of the convex ring.

[0014] In order to achieve the above-mentioned purpose, another technical solution adopted in the present application is: to provide a transformer bushing, wherein the transformer bushing includes the head assembly described in any of the above-mentioned embodiments.

[0015] Different from the prior art, the transformer head assembly provided by the present application includes a cover body, a conductive tube and a conductive connector, wherein the cover body includes a relative outer surface and an inner surface, and the cover body is provided with a first through hole and a second through hole, the first through hole penetrates the outer surface and the inner surface, and the second through hole penetrates the outer surface and the hole wall of the first through hole; one end of the conductive tube is located in the first through hole; the conductive connector is located in the second through hole, and one end of the conductive connector abuts against the conductive tube in the first through hole, so that the cover body and the conductive tube are electrically connected. The beneficial effect of the present application is that due to the effect of the conductive connector, even if the connection between the conductive tube and the cover body at the axial seal is in a poor contact state, the conductive connector can make the cover body and the conductive tube equal in potential, thereby preventing problems such as local discharge, dielectric loss and abnormal capacitance caused by the floating potential generated by the conductive tube.

[0016] In addition, the transformer bushing head assembly provided in the present application also includes a conductive elastic member, the two ends of which are respectively abutted against the conductive connector and the conductive tube; during use, the internal temperature of the transformer bushing will change, and the conductive tube will expand and contract due to heat. On the one hand, the conductive elastic member can reduce the contact force between the conductive tube and the conductive connector during thermal expansion, thereby reducing damage to the conductive tube, the cover body, and the conductive connector; on the other hand, the conductive elastic member can keep the cover body and the conductive tube electrically connected when the conductive tube has poor contact with the conductive connector due to cold contraction, thereby achieving equal potential between the two, thereby preventing local discharge, dielectric loss, and abnormal capacitance caused by the floating potential generated by the conductive tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0018] Figure 1 This is a structural schematic diagram of an implementation method of a transformer bushing head assembly of the present application;

[0019] Figure 2 This is a structural schematic diagram of another embodiment of the transformer bushing head assembly of the present application;

[0020] Figure 3 for Figure 1 A schematic structural diagram of a convex ring embodiment;

[0021] Figure 4 This is a schematic structural diagram of an implementation method of a transformer bushing of the present application. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] See also Figure 1 , Figure 1 This is a schematic structural diagram of an embodiment of a transformer bushing head assembly of the present application. The head assembly 20 includes an oil pillow 10, a conductive tube 12, and a conductive connector 14.

[0024] The oil pillow 10 includes a cover 100, which includes an outer surface 1000 and an inner surface 1002 opposite to each other. The cover 100 is provided with a first through hole 1004 and a second through hole 1006. The first through hole 1004 penetrates the outer surface 1000 and the inner surface 1002, and the second through hole 1006 penetrates the outer surface 1000 and the hole wall of the first through hole 1004. In this embodiment, the cover 100 has a conductive property and its material can be metal, such as iron, aluminum, stainless steel, etc. The oil pillow 10 also includes a cabinet 102, which is a hollow structure. The cover 100 is located at an opening on one side of the cabinet 102. The outer surface 1000 of the cover 100 is defined as all surfaces not covered by the cabinet 102, and the inner surface 1002 of the cover 100 is defined as a side surface covered by the cabinet 102. For example, assuming that the cover body 100 is a rectangular parallelepiped, the outer surface 1000 of the cover body 100 includes an upper surface, a left side, a right side, a front side and a rear side, the inner surface 1002 of the cover body 100 includes a lower surface, the first through hole 1004 passes through the upper surface and the lower surface of the cover body 100, and can be located at the center of the cover body 100, and the second through hole 1006 can pass through the left side, the right side, the front side or the rear side to the inner wall of the first through hole 1004.

[0025] One end 120 of the conductive tube 12 is located in the first through hole 1004 of the cover 100 . In the present embodiment, the conductive tube 12 is made of metal, such as aluminum.

[0026] The conductive connector 14 is located in the second through hole 1006 of the cover 100, and one end 140 of the conductive connector 14 abuts against the conductive tube 12 in the first through hole 1004, so that the cover 100 is electrically connected to the conductive tube 12. In this embodiment, the conductive connector 14 is made of metal, such as iron, aluminum, stainless steel, etc. Due to the function of the conductive connector 14, even if the connection between the conductive tube 12 and the cover 100 at the axial seal is in a poor contact state, the conductive connector 14 can make the potential of the cover 100 and the conductive tube 12 the same, thereby preventing the occurrence of partial discharge, dielectric loss and abnormal capacitance due to the floating potential of the conductive tube 12.

[0027] In one embodiment, the first through hole 1004 and the second through hole 1006 can be cylindrical through holes, prismatic through holes, etc.; the axis angle between the second through hole 1006 and the first through hole 1004 is between 0 and 180 degrees, for example, 45 degrees, 90 degrees, 135 degrees, etc., and the corresponding axis angle can be designed according to the position of the conductive tube 12, or the position of the conductive tube 12 can be set according to the axis angle, as long as the conductive connector 14 located in the second through hole 1006 is in contact with the conductive tube 12. For example, the second through hole 1006 is formed with an opening on the hole wall of the first through hole 1004. When one end 120 of the conductive tube 12 does not completely cover the opening, as shown in FIG. Figure 1 As shown in FIG, the axis angle between the second through hole 1006 and the first through hole 1004 is an obtuse angle (i.e. Figure 1 The second through hole 1006 is inclined Figure 1 For another example, when one end 120a of the conductive tube 12a covers the opening, the angle between the axis of the second through hole 1006a and the axis of the first through hole 1004a may be a right angle, an acute angle, or an obtuse angle, such as Figure 2 As shown, Figure 2 This is a schematic structural diagram of another embodiment of the transformer bushing head assembly of the present application.

[0028] In another embodiment, please refer again to Figure 1 , the conductive connector 14 includes a screw, the screw is provided with an external thread (not shown), and the inner wall of the second through hole 1006 is provided with an internal thread matching the external thread (not shown). Through the cooperation of the external thread and the internal thread, the position of the conductive connector 14 and the cover body 100 is relatively fixed; in this embodiment, the screw can be a hexagon socket screw, so as to be easily and quickly installed in the second through hole 1006. Of course, in other embodiments, the conductive connector 14 can also be a conductive rod, whose outer diameter matches the inner diameter of the second through hole 1006, and the two are fitted by interference, so that the position of the conductive rod and the cover body 100 is relatively fixed; of course, conductive glue can also be coated on the periphery of the conductive rod, and the position of the conductive rod and the cover body 100 is further fixed by the effect of the conductive glue.

[0029] In yet another embodiment, please refer again to Figure 1 The head assembly 20 provided in the present application also includes a conductive elastic member 16, the two ends of which are respectively against the conductive connector 14 and the conductive tube 12, and the conductive elastic member 16 can be formed of a metal material, such as iron, aluminum, stainless steel, etc. During use, the temperature inside the transformer bushing will change, and the conductive tube 12 will expand and contract due to heat. On the one hand, the conductive elastic member 16 can reduce the contact force between the conductive tube 12 and the conductive connector 14 during thermal expansion, thereby reducing damage to the conductive tube 12, the cover 100, and the conductive connector 14; on the other hand, the conductive elastic member 16 can keep the cover 100 and the conductive tube 12 electrically connected when the conductive tube 12 is in poor contact with the conductive connector 14 due to cold contraction, thereby achieving equal potential between the two, thereby preventing problems such as local discharge, dielectric loss, and abnormal capacitance caused by the floating potential of the conductive tube 12.

[0030] In a specific application scenario, such as Figure 1As shown, the conductive elastic member 16 includes a spring, and the diameter of the end of the screw adjacent to the conductive tube 12 is smaller than the diameter of the end away from the conductive tube 12, so as to form a step on the outer wall of the screw; one end of the spring abuts against the conductive tube 12, and the other end of the spring is sleeved on the end of the screw adjacent to the conductive tube 12, and abuts against the step of the screw. Of course, in other application scenarios, the conductive elastic member 16 can also be other materials, such as conductive silicone. When the conductive elastic member 16 is conductive silicone, the conductive connector 14 can also be conductive silicone, that is, at this time, the conductive elastic member 16 and the conductive connector 14 are integral.

[0031] In another embodiment, please refer to Figure 1 The cover body 100 forms a convex ring 104 axially away from the cover body 100 at the edge of the first through hole 1004. The convex ring 104 and the cover body 100 form a structure similar to a step. The convex ring 104 and the cover body 100 can be integrally formed. The second through hole 1006 passes through the outer wall and the inner wall of the convex ring 104. Figure 1 The number of the second through holes 1006 is one, and of course, the number of the second through holes 1006 can also be multiple (for example, two, three, four, etc.). The multiple second through holes 1006 are arranged at the convex ring 104, or at the connection between the convex ring 104 and the cover body 100, such as Figure 3 As shown, Figure 3 for Figure 1 The schematic top view of an embodiment of the central convex ring 104 shows that four second through holes 1006 are evenly arranged on the convex ring 104 .

[0032] In another embodiment, please continue to refer to Figure 1The conductive tube 12 provided in the present application is a hollow structure, and the head assembly 20 provided in the present application also includes a current-carrying rod 18 and a positioning pin 11; wherein, the current-carrying rod 18 is inserted into the conductive tube 12 (that is, one end of the current-carrying rod 18 is located in the conductive tube 12, and the other end of the current-carrying rod 18 is located outside the conductive tube 12), the current-carrying rod 18 is passed through the first through hole 1004 (that is, the current-carrying rod 18 passes through the first through hole 1004, and both ends of the current-carrying rod 18 are located outside the first through hole 1004), and the current-carrying rod 18 does not contact the inner wall of the conductive tube 12; one end of the current-carrying rod 18 located in the conductive tube 12 is provided with a first groove that is recessed toward the other end of the current-carrying rod 18 180, the lead wire of the transformer winding in the transformer cabinet is welded to the bottom of the first groove 180; the positioning pin 11 crosses the current-carrying rod 18, and the two ends of the positioning pin 11 are relatively fixed to the position of the convex ring 104; in the present embodiment, the current-carrying rod 18 includes a first area 182 located on the same horizontal plane as the convex ring 104, and the first area 182 is provided with a through hole (not marked), the through hole is perpendicular to the axial direction of the current-carrying rod 18, and the positioning pin 11 is penetrated in the through hole; the convex ring 104 is provided with a second groove (not marked) corresponding to the position of the positioning pin 11 to accommodate the end of the positioning pin 11, thereby fixing the position of the current-carrying rod 18.

[0033] In another embodiment, please continue to refer to Figure 1 The head assembly 20 provided in the present application also includes a terminal block 13, which is covered on the first through hole 1004 of the cover body 100, and the terminal block 13 is provided with a receiving cavity 130 for receiving the other end of the current-carrying rod 18 outside the conductive tube 12; the terminal block 13 includes an extension portion 132 in contact with the cover body 100, and the extension portion 132 can be fixed to the cover body 100 by screws. A third groove 134 is provided on the side wall of the receiving cavity 130 of the terminal block 13, and the third groove 134 is used to receive a current-carrying spring. The current in the transformer winding flows out after passing through the current-carrying rod 18, the current-carrying spring, and the terminal block 13, and the current-carrying rod 18 and the terminal block 13 are at the same potential. Since the terminal block 13 and the cover body 100 are fixed by screws, the terminal block 13 and the cover body 100 are at the same potential. In addition, in this embodiment, the cover body 100 is provided with a first through hole 1004 and a second through hole 1006, the second through hole 1006 is connected to the first through hole 1004, one end 120 of the conductive tube 12 is located in the first through hole 1004, a conductive connector 14 is provided in the second through hole 1006, one end 140 of the conductive connector 14 abuts against the conductive tube 12, and due to the effect of the conductive connector 14, the cover body 100 and the conductive tube 12 are at the same potential. That is, the conductive tube 12, the cover body 100, the current-carrying rod 18, and the terminal block 13 in the head assembly 20 provided by the present application are at the same potential, thereby reducing the probability of partial discharge, dielectric loss, and abnormal capacitance in the entire head assembly 20.

[0034] Of course, in other embodiments, the head assembly 20 provided in the present application may also include other common structures, such as a pressure equalizing ring, etc., which will not be elaborated in the present application.

[0035] See also Figure 4 , Figure 4 This is a schematic diagram of the structure of an embodiment of a transformer bushing of the present application. The transformer bushing 40 includes a head assembly 20. The specific structure of the head assembly 20 can refer to any of the above embodiments and will not be repeated here. Of course, the transformer bushing 40 may also include other common structures, such as a tail assembly 22, etc., which will not be described in detail in the present application.

[0036] In summary, different from the prior art, the transformer head assembly provided by the present application includes a cover body, a conductive tube and a conductive connector, wherein the cover body includes a relative outer surface and an inner surface, and the cover body is provided with a first through hole and a second through hole, the first through hole penetrates the outer surface and the inner surface, and the second through hole penetrates the outer surface and the hole wall of the first through hole; one end of the conductive tube is located in the first through hole; the conductive connector is located in the second through hole, and one end of the conductive connector abuts against the conductive tube in the first through hole, so that the cover body and the conductive tube are electrically connected. Due to the effect of the conductive connector, even if the connection between the conductive tube and the cover body at the axial seal is in a poor contact state, the conductive connector can make the potential of the cover body and the conductive tube the same, thereby reducing the occurrence of partial discharge, dielectric loss and abnormal capacitance; at the same time, it can also reduce the phenomenon of partial discharge, dielectric loss and abnormal capacitance caused by the floating potential of the conductive tube. In addition, the transformer bushing head assembly provided in the present application also includes a conductive elastic member, the two ends of which are respectively abutted against the conductive connector and the conductive tube; during use, the internal temperature of the transformer bushing will change, and the conductive tube will expand and contract due to heat. On the one hand, the conductive elastic member can reduce the contact force between the conductive tube and the conductive connector during thermal expansion, thereby reducing damage to the conductive tube, the cover body, and the conductive connector; on the other hand, the conductive elastic member can keep the cover body and the conductive tube electrically connected when the conductive tube has poor contact with the conductive connector due to cold contraction, thereby achieving equal potential between the two, thereby preventing local discharge, dielectric loss, and abnormal capacitance caused by the floating potential generated by the conductive tube.

[0037] The above are only implementation methods of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A transformer bushing head assembly, characterized in that: The transformer bushing head assembly comprises: An oil pillow, comprising a cover body, the cover body comprising an outer surface and an inner surface opposite to each other, the cover body being provided with a first through hole and a second through hole, the first through hole penetrating the outer surface and the inner surface, the second through hole penetrating the outer surface and a hole wall of the first through hole; a conductive tube, one end of which is located in the first through hole; a conductive connecting member, located in the second through hole, one end of the conductive connecting member abutting against the conductive tube in the first through hole, so that the cover body is electrically connected to the conductive tube; A conductive elastic member, two ends of which are respectively abutted against the conductive connecting member and the conductive tube; The conductive connecting member comprises a screw, the screw is provided with an external thread, and the inner wall of the second through hole is provided with an internal thread matching the external thread; The diameter of the screw at one end adjacent to the conductive tube is smaller than the diameter of the screw at one end away from the conductive tube, so as to form a step on the outer wall of the screw; The conductive elastic member comprises a spring, one end of the spring abuts against the conductive tube, and the other end of the spring is sleeved on an end of the screw adjacent to the conductive tube and abuts against the step of the screw; The cover body, the conductive tube, the conductive connecting member and the conductive elastic member are formed of metal material.

2. The transformer bushing head assembly according to claim 1, characterized in that: The cover body forms a convex ring at the edge of the first through hole axially away from the cover body; The second through hole passes through the outer wall of the convex ring and the inner wall of the convex ring.

3. The transformer bushing head assembly according to claim 2, characterized in that: There are a plurality of second through holes, which are arranged on the convex ring or at the connection between the convex ring and the cover body.

4. The transformer bushing head assembly according to claim 1, characterized in that: The included angle between the axes of the second through hole and the first through hole is between 0 and 180 degrees.

5. The transformer bushing head assembly according to claim 2, characterized in that: The conductive tube is a hollow structure, and the transformer bushing head assembly further includes: A current-carrying rod is inserted into the conductive tube, the current-carrying rod is passed through the first through hole, and the current-carrying rod does not contact the inner wall of the conductive tube; A positioning pin crosses the current-carrying rod, and two ends of the positioning pin are relatively fixed to the convex ring.

6. A transformer bushing, characterized in that: The transformer bushing comprises the transformer bushing head assembly according to any one of claims 1 to 5.

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