Current transformer wiring terminal fixing structure

Abstract

The utility model provides a current transformer wiring terminal fixing structure, relates to the technical field of current transformer wiring terminals, and is used for improving the reliability of connection between the current transformer wiring terminals and wires. The current transformer wiring terminal fixing structure comprises a conductive body and a protective shell, one end of the conductive body is provided with a positioning boss, and the positioning boss is used for tin soldering with a wire; the protective shell comprises an upper shell body and a lower shell body, the upper shell body and the lower shell body are detachably connected and define a containing cavity, the positioning boss is located in the containing cavity, and the conductive body is detachably connected with the upper shell body. Therefore, the tin material can permeate into the gaps between the wire core strands to form a metallurgical bonding layer, which is beneficial for improving the reliability of the connection between the positioning boss and the wire, thereby reducing the energy loss in the power transmission process. Besides, through the accommodating cavity formed by the upper shell and the lower shell, protection can be formed at the joint of the positioning boss and the wire, so that the connection reliability can be further guaranteed.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of current transformer wiring terminals, in particular to a current transformer wiring terminal fixing structure. BACKGROUND

[0002] In modern power systems, current transformers play an indispensable role as a kind of extremely critical equipment. They can convert large currents on the primary side into small currents on the secondary side in proportion, so as to facilitate the access of measurement, protection and control devices. Its application is widely used in power generation, power transmission, power transformation, power distribution and power consumption, etc. It is an important foundation to ensure the safe, stable and reliable operation of the power system. For example, in a substation, current transformers are used to measure and monitor the current of power transmission lines, providing accurate current signals for relay protection devices. When a line fault occurs, the relay protection device will act quickly according to the signal transmitted by the current transformer, cutting off the fault line, thereby protecting the safety of the entire power system.

[0003] However, the traditional current transformer wiring terminal has many problems in the connection mode. Among them, the screw compression type wiring terminal is a relatively common connection mode, which fixes the wire on the wiring terminal by the pressure generated by tightening the screw. However, in the actual operation process, this method is relatively cumbersome, and the operator needs to use a screwdriver or other tools to tighten the operation. For a large number of wiring work, it not only consumes time and effort, but also is low in efficiency. At the same time, the screw compression method has high technical requirements for the operator. If the screw is not tightened uniformly or insufficiently, it is easy to cause poor contact of the wire, thereby affecting the stability of current transmission. In addition, in the long-term use process, due to the vibration of the equipment, the change of temperature and the influence of environmental factors, the screw is easy to loosen, which increases the contact resistance between the wire and the wiring terminal, and in severe cases, it may even cause heating, sparking and other safety hazards, which threatens the stable operation of the power system. Practical new type content

[0004] In order to solve the above technical problems, the application provides a current transformer wiring terminal fixing structure for improving the reliability of the connection between the current transformer wiring terminal and the wire.

[0005] To achieve the above purpose, the embodiments of the present application adopt the following technical solutions:

[0006] The embodiment of the present application provides a current transformer wiring terminal fixing structure, which comprises a conductive body and a protective shell, one end of the conductive body is provided with a positioning boss, and the positioning boss is used for tin soldering with a wire; the protective shell comprises an upper shell and a lower shell, the upper shell and the lower shell are detachably connected and surround a containing cavity, the positioning boss is located in the containing cavity, and the conductive body is detachably connected with the upper shell.

[0007] According to the current transformer wiring terminal fixing structure provided by the embodiment of the present application, the positioning boss is arranged at one end of the conductive body and connected with the wire through tin soldering, tin material can penetrate into the gap between the wire cores to form a metallurgical bonding layer, the reliability of the connection between the positioning boss and the wire is improved, and thus the energy loss in the process of power transmission can be reduced. In addition, the containing cavity formed by the upper shell and the lower shell can protect the connection between the positioning boss and the wire, and thus the reliability of the connection can be further ensured.

[0008] In a possible implementation manner, the conductive body comprises a connecting part and a body part, the connecting part is arranged at one end of the body part, the positioning boss is arranged on the connecting part, and the connecting part is provided with a flow guide groove, the flow guide groove is located on one side of the positioning boss close to the body part.

[0009] In a possible implementation manner, the containing cavity is provided with a first positioning protrusion and a second positioning protrusion, the first positioning protrusion is arranged on the upper shell, the second positioning protrusion is arranged on the lower shell, the first positioning protrusion and the second positioning protrusion surround an installation cavity, and part of the body part is located in the installation cavity.

[0010] In a possible implementation manner, a plurality of annular clamping grooves are arranged on the body part, the annular clamping grooves are located in the installation cavity, a plurality of fixing protrusions are arranged on the first positioning protrusion, and the fixing protrusions are matched with the annular clamping grooves.

[0011] In a possible implementation manner, the upper shell is provided with a glue injection hole, and the glue injection hole is opposite to the connecting part.

[0012] In a possible implementation manner, the current transformer wiring terminal fixing structure further comprises a sealing plug, and the sealing plug is detachably arranged at the glue injection hole.

[0013] In a possible implementation manner, a first included angle is formed between the extension direction of the positioning boss and the extension direction of the conductive body, and the value of the first included angle ranges from 8° to 12°.

[0014] In a possible implementation, a plurality of anti-skid lines are arranged on the positioning boss in the extending direction of the positioning boss.

[0015] In a possible implementation, the anti-skid lines and the positioning boss form a second included angle, and the second included angle ranges from 15 degrees to 20 degrees.

[0016] In a possible implementation, a sealing ring is arranged on the side of the lower shell facing the upper shell. BRIEF DESCRIPTION OF DRAWINGS

[0017] The drawings incorporated in the specification hereof and forming a part thereof illustrate embodiments consistent with the present application and together with the description serve to explain the principles of the application.

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the embodiments or the related art description will be briefly introduced here. Obviously, for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative labor.

[0019] Figure 1 A schematic view of a current transformer wiring terminal fixing structure provided by some embodiments of the present application.

[0020] Reference signs:

[0021] 100, current transformer wiring terminal fixing structure;

[0022] 1, conductive body; 11, connecting portion; 111, positioning boss; 112, flow guide groove; 12, body portion; 121, annular clamping groove;

[0023] 2, protective shell; 21, upper shell; 211, first positioning protrusion; 212, fixing protrusion; 213, glue injection hole; 22, lower shell; 221, second positioning protrusion; 23, accommodating cavity;

[0024] 3, sealing ring. DETAILED DESCRIPTION

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the embodiments or the related art description will be briefly introduced here. Obviously, for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative labor.

[0026] In the description of the utility model, it is understood that the terms "upper", "lower", "front", "rear", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the utility model.

[0027] In the description of the embodiments of the present application, unless otherwise specified and limited, the terms "mounting", "connection", "connection" should be understood in a broad sense, for example, "connection" can be detachable connection, or it can be non-detachable connection, it can be direct connection, or it can be indirect connection through intermediate medium. Among them, "fixed connection" refers to the connection of each other and the relative positional relationship after connection does not change. In addition, the orientation language mentioned in the embodiments of the present application, such as "inner", "outer" and the like, is only the direction of the drawings, therefore, the orientation language used is for better and clearer description and understanding of the embodiments of the present application, and is not intended to indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0028] In the description of the embodiments of the present application, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or device. Without more limitation, the element defined by the sentence "including a" does not exclude the presence of another identical element in the process, method, article or device including the element. Without more limitation, the element defined by the sentence "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0029] In modern power system, current transformer as a kind of extremely critical equipment, plays an indispensable role. It can convert the large current of primary side into small current of secondary side in proportion, so as to facilitate the access of measurement, protection and control equipment. Its application is widely covered in power generation, power transmission, power transformation, power distribution and power utilization, etc. It is an important foundation to ensure the safe, stable and reliable operation of power system. For example, in the substation, the current transformer is used to measure and monitor the current of power transmission line, and provides accurate current signal for the relay protection device. When the line fails, the relay protection device acts quickly according to the signal transmitted by the current transformer, and cuts off the fault line, so as to protect the safety of the whole power system.

[0030] However, the traditional current transformer terminal has many problems in the connection mode. Among them, the screw compression type terminal is a common connection mode, which fixes the wire on the terminal by the pressure generated by tightening the screw. However, in the actual operation process, this method is relatively cumbersome, and the operator needs to use a screwdriver and other tools to tighten the operation. For a large number of wiring work, it not only consumes time and effort, but also is low in efficiency. At the same time, the screw compression method has high technical requirements for the operator. If the screw is not uniformly or insufficiently tightened, it is easy to cause poor contact of the wire, thereby affecting the stability of current transmission. In addition, in the long-term use process, due to the vibration of the equipment, the change of temperature and the influence of environmental factors, the screw is easy to loosen, which increases the contact resistance between the wire and the terminal, and even causes safety hazards such as heating and sparking, which threatens the stable operation of the power system.

[0031] In order to solve the above technical problems, the current transformer terminal fixing structure is provided.

[0032] Please refer to Figure 1 , Figure 1 The schematic diagram of the current transformer terminal fixing structure provided by some embodiments of the present application is shown in the figure. The current transformer terminal fixing structure 100 can include a conductive body 1 and a protective shell 2.

[0033] For example, the conductive body 1 can be made of T2 red copper turning, so as to reduce the resistance and reduce the energy loss in the process of electric energy transmission. After turning, surface tin plating treatment can be carried out, and the thickness of the tin plating layer can be controlled to be ≥8μm. Before tin plating, chemical polishing treatment is adopted, and the ratio of chemical polishing liquid is nitric acid: phosphoric acid: water = 1:3:2. The treatment temperature is kept at 45℃, and the time is 30s. After such treatment, the surface roughness Ra≤0.8μm, which can enhance the oxidation resistance and corrosion resistance, and prolong the service life of the terminal.

[0034] For example, the wire can adopt 4mm 2 multi-strand copper core wire, each strand with a diameter of 0.15mm and 19 strands. The wire of this structure has good flexibility and conductivity. The tin content of the tin-plated core is ≥99.3%, which can improve the weldability and oxidation resistance of the wire. The stripping length is strictly controlled to be 12±0.5mm, which ensures that the core can cooperate well with the terminal in the subsequent connection process, and at the same time avoids affecting the connection quality due to excessive or insufficient stripping.

[0035] One end of the conductive body 1 can be provided with a positioning boss 111 for soldering with the wire. Specifically, the stripped wire core end is wound into a ring shape and is sleeved on the positioning boss 111. The inner diameter of the wire core ring is 0.1-0.2mm larger than the outer diameter of the positioning boss 111, and the number of winding turns is greater than or equal to 2. Then a constant temperature soldering gun is used for welding.

[0036] Thus, by soldering the positioning boss 111 and the wire, the tin material can penetrate into the gap between the wire core strands to form a metallurgical bonding layer, thereby reducing energy loss during power transmission.

[0037] The protective shell 2 can include an upper shell 21 and a lower shell 22. The upper shell 21 and the lower shell 22 are detachably connected and surround a receiving cavity 23, and the positioning boss 111 is located in the receiving cavity 23. Specifically, part of the conductive body 1 is located in the receiving cavity 23, and there can be a gap between the inner wall of the receiving cavity 23 and the positioning boss 111, so that interference with the positioning boss 111 can be avoided.

[0038] Thus, by detachably connecting the upper shell 21 and the lower shell 22, the connection between the wire and the positioning boss 111 can be protected, thereby facilitating the reliability of the current transformer terminal fixation. In addition, it is also convenient for disassembly and maintenance, thereby facilitating the reduction of maintenance cost.

[0039] The conductive body 1 is detachably connected with the upper shell 21. The conductive body 1 and the upper shell 21 can be detachably connected by fasteners, clamping or other means.

[0040] According to the current transformer terminal fixation structure 100 of the embodiment of the present application, by providing a positioning boss 111 at one end of the conductive body 1 and soldering the positioning boss 111 with the wire, the tin material can penetrate into the gap between the wire core strands to form a metallurgical bonding layer, thereby facilitating the reliability of the connection between the positioning boss 111 and the wire, and reducing energy loss during power transmission. In addition, the receiving cavity 23 formed by the upper shell 21 and the lower shell 22 can protect the connection between the positioning boss 111 and the wire, thereby further ensuring the reliability of the connection.

[0041] Please continue to refer to Figure 1 In some embodiments, a plurality of anti-skid lines are provided on the positioning boss 111 in the extension direction of the positioning boss 111. Specifically, the first turn of the wire core is pressed onto the anti-skid lines at the edge, and the anti-skid lines are engaged with the wire core ring in the reverse direction by virtue of the characteristics of the inverted tooth-shaped anti-skid lines, thereby enhancing the stability of the wire. The last turn can be embedded between the two anti-skid lines at the top of the positioning boss 111. Thus, displacement of the wire during welding can be prevented, thereby facilitating the connection efficiency of the wire.

[0042] Exemplarily, the height of the anti-skid lines can be greater than or equal to 0.5 mm. In this way, the anti-skid effect of the anti-skid lines can be ensured.

[0043] Please continue to refer to Figure 1 In some embodiments, the anti-skid lines have a second included angle with the positioning boss 111, and the second included angle ranges from 15° to 20°. In this way, the anti-skid effect of the anti-skid lines can be improved.

[0044] Exemplarily, the second included angle can be 16°, 17°, 18°, 19°, 20°, etc.

[0045] Please continue to refer to Figure 1 In some embodiments, the positioning boss 111 has a first included angle with the extension direction of the conductive body 1. The first included angle ranges from 8° to 12°. In this way, the reliability of the connection between the wire and the positioning boss 111 can be improved.

[0046] Exemplarily, the first included angle can be 8°, 9°, 10°, 11°, 12°, etc.

[0047] Please continue to refer to Figure 1 In some embodiments, the conductive body 1 can include a connecting portion 11 and a body portion 12. The connecting portion 11 is arranged at one end of the body portion 12, the positioning boss 111 is arranged on the connecting portion 11, and the connecting portion 11 has a flow guide groove 112 located on the side of the positioning boss 111 close to the body portion 12. In this way, during the soldering process, a solder anchor point can be formed in the flow guide groove 112, which is conducive to improving the reliability of soldering.

[0048] Please continue to refer to Figure 1 In some embodiments, the accommodating cavity 23 is provided with a first positioning protrusion 211 and a second positioning protrusion 221. The first positioning protrusion 211 is arranged on the upper shell 21, and the second positioning protrusion 221 is arranged on the lower shell 22. The first positioning protrusion 211 and the second positioning protrusion 221 enclose an installation cavity, and part of the body portion 12 is located in the installation cavity. In this way, the accommodating cavity 23 can be divided into multiple chambers by the first positioning protrusion 211 and the second positioning protrusion 221, and the installation cavity enclosed by the first positioning protrusion 211 and the second positioning protrusion 221 can fix the body portion 12, thereby facilitating the assembly of the conductive body 1 and further improving the connection efficiency.

[0049] Please continue to refer to Figure 1In some embodiments, the body part 12 is provided with a plurality of annular clamping grooves 121. The annular clamping grooves 121 are located in the mounting cavity, and the first positioning protrusion 211 is provided with a plurality of fixing protrusions 212 which are matched with the annular clamping grooves 121. The plurality of annular clamping grooves 121 can be arranged at intervals along the extension direction of the body part 12, and the plurality of fixing protrusions 212 on the first positioning protrusion 211 are matched with the annular clamping grooves 121, so that the body part 12 can be fixed in the mounting cavity. Thus, the body part 12 can be conveniently mounted and fixed, thereby improving the assembly efficiency.

[0050] It should be noted that the body part 12 can also be provided with the fixing protrusions 212, and the first positioning protrusion 211 can be provided with the annular clamping grooves 121, which are not limited in the present application.

[0051] Please continue to refer to Figure 1 In some embodiments, the upper shell 21 is provided with a glue injection hole 213. The glue injection hole 213 is opposite to the connecting part 11. Thus, vulcanized silicone rubber can be injected into the accommodating cavity 23 through the glue injection hole 213, and the silicone rubber has good insulation performance, elasticity and temperature resistance. After being injected into the glue injection hole 213, the silicone rubber can be vulcanized and formed at room temperature to form a composite layer with elastic buffering and insulation protection, thereby providing reliable protection for the connection between the conductive body 1 and the wire.

[0052] Please continue to refer to Figure 1 In some embodiments, the current transformer wiring terminal fixing structure 100 further comprises a sealing plug which is detachably arranged at the glue injection hole 213. Thus, when maintenance is needed, the sealing plug can be opened, and a glue dissolving agent can be injected into the glue injection hole 213, so that the overall structure can be avoided from being damaged, the maintainability requirement of the power equipment is met, the maintenance cost and time are reduced, and the operation efficiency of the power system is improved.

[0053] Please continue to refer to Figure 1 In some embodiments, the side of the lower shell 22 facing the upper shell 21 is provided with a sealing ring 3. Thus, the sealing of the mounting cavity can be achieved, and the electrical performance of the wiring part can be protected from impurities such as dust and moisture.

[0054] The fixing process of the current transformer wiring terminal fixing structure 100 of the embodiment of the present application will be described below:

[0055] Wire positioning pretreatment: Use professional stripping tools to strip the ends of the wires to be connected, exposing the wire core. The stripping length is strictly controlled within 12 ± 0.5 mm. The wire core end is wound into a ring shape and fitted on the positioning boss 111. The positioning boss 111 is a cylinder with a diameter of 3 mm and a height of 2.5 mm. The angle between its axis and the axis of the conductive body 1 is set between 8°-12°, forming an inclined positioning surface. The interference amount between the inner diameter of the wire core ring and the outer diameter of the positioning boss 111 is controlled within 0.1-0.2 mm, ensuring that the wire can be tightly fitted on the positioning boss 111. The number of windings is not less than 2. The reverse engagement characteristics of the reverse direction of the reverse tooth-shaped anti-slip pattern and the wire core ring winding direction enhance the stability of the wire. Special tools can be used to assist during winding to ensure the tightness and uniformity of the winding.

[0056] Soldering welding reinforcement: Select a constant temperature soldering gun with a conical iron head at the front end, the cone angle is 60°, and the end face diameter is 1.5 mm. Before welding, preheat the soldering gun to the set temperature. When heating, the contact area between the iron head and the positioning boss 111 is controlled to be ≤3 mm 2 , so as to achieve precise heating and avoid the influence of heat diffusion on other components. The local temperature rise rate is controlled at 50℃ per second, and the heating temperature is strictly controlled within 230℃-250℃, lasting for 3-5 seconds. During heating, tin is slowly added to the contact area between the positioning boss 111 and the wire core, so that the tin penetrates into the gap between the wire core strands to form a metallurgical bonding layer, and at the same time, an anchor point of tin is formed in the flow groove 112 pre-opened at the bottom of the terminal. During welding, the melting and penetration of tin should be closely monitored to ensure the welding quality.

[0057] Protective sealing packaging: the welded conductive body 1 is buckled in the protective shell 2, and the first positioning protrusion 211 and the second positioning protrusion 221 on the inner side of the protective shell 2 are tightly fitted with the terminal. The multiple fixing protrusions 212 on the first positioning protrusion 211 form an interference fit with the multiple annular clamping grooves 121 on the body part 12. When buckling the protective shell 2, the clamping torque is controlled within 1.2-1.5 N·m, ensuring that the compression amount of the sealing ring 3 reaches 30% when sealed, achieving 360° sealing. The protective shell 2 has a reserved glue injection hole 213 at the top, and room temperature vulcanized silicone rubber is injected into the glue injection hole 213 using a vacuum glue injection process until the welding point is submerged, ensuring that the silicone rubber is bubble-free and forms a reliable protective layer.

[0058] In the description of the present specification, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0059] The above merely describes a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A current transformer terminal fixing structure, characterized in that, The current transformer terminal fixing structure includes: A conductive body, one end of which is provided with a positioning boss for soldering with a wire; A protective shell, comprising an upper shell and a lower shell, the upper shell and the lower shell being detachably connected and enclosing a receiving cavity, the positioning boss being located within the receiving cavity, and the conductive body being detachably connected to the upper shell.

2. The current transformer terminal fixing structure according to claim 1, characterized in that, The conductive body includes a connecting part and a body part. The connecting part is disposed at one end of the body part, and the positioning boss is disposed on the connecting part. The connecting part has a flow guide groove, which is located on the side of the positioning boss closer to the body part.

3. The current transformer terminal fixing structure according to claim 2, characterized in that, The receiving cavity is provided with a first positioning protrusion and a second positioning protrusion. The first positioning protrusion is disposed on the upper housing, and the second positioning protrusion is disposed on the lower housing. The first positioning protrusion and the second positioning protrusion surround the mounting cavity, and a portion of the main body is located within the mounting cavity.

4. The current transformer terminal fixing structure according to claim 3, characterized in that, The main body is provided with multiple annular slots, which are located inside the mounting cavity. The first positioning protrusion is provided with multiple fixing protrusions, which cooperate with the annular slots.

5. The current transformer terminal fixing structure according to claim 3, characterized in that, The upper housing is provided with an injection hole, which is directly opposite the connecting part.

6. The current transformer terminal fixing structure according to claim 5, characterized in that, The current transformer terminal fixing structure also includes a sealing plug, which is detachably disposed at the glue injection hole.

7. The current transformer terminal fixing structure according to claim 1, characterized in that, The extension direction of the positioning boss and the extension direction of the conductive body have a first angle, the first angle being between 8° and 12°.

8. The current transformer terminal fixing structure according to claim 1, characterized in that, In the extending direction of the positioning boss, the positioning boss is provided with multiple anti-slip textures.

9. The current transformer terminal fixing structure according to claim 8, characterized in that, The anti-slip texture and the positioning boss have a second included angle, the value of which is between 15° and 20°.

10. The current transformer terminal fixing structure according to claim 1, characterized in that, A sealing ring is provided on the side of the lower housing facing the upper housing.

Images