A high-precision current transformer for metering

Abstract

The utility model relates to the field of electric power system metering equipment discloses a high accuracy current transformer for metering, including the shell, the outer side of shell is provided with heat abstractor, the outer side of heat abstractor is provided with locking assembly, heat abstractor includes inner lining, the inner lining is provided with two groups, two groups the inner lining is in line with the upper outer side of shell, the outer camber surface fixedly connected with heat conduction piece b in the inner lining. In the utility model, through two groups of inner lining closely in line with the upper outer side of shell, directly contact the mutual inductor body, the heat generated by the iron core, winding in the shell inside is conducted fast, the heat conduction piece b of outer camber surface and the heat conduction piece a of radioactive distribution expand the heat dissipation area, cooperate the fan of fixed shell lower part, can continue to input airflow in the channel, and the deflection guide portion of outer sleeve a, b inner ring surface is in line with the outer side of heat conduction piece a, can guide airflow to flow through all heat conduction pieces evenly, avoid local heat accumulation, ensure the precision of current transformer.

Description

Technical Field

[0001] This utility model relates to the field of power system metering equipment, and in particular to a high-precision current transformer for metering. Background Technology

[0002] In power system energy metering, load monitoring and power dispatching, current transformers are the core equipment for realizing "converting large currents into small currents". Their accuracy directly determines the accuracy of energy metering, the reliability of power parameter monitoring, and thus affects the fairness of power market transactions and the efficiency of power grid operation.

[0003] The metering accuracy of a current transformer essentially depends on the magnetic permeability of its internal core and the conductivity of its windings. The stability of these parameters directly determines the accuracy of the conversion from "large primary current to small secondary current." However, during the operation of the transformer, the core generates heat due to hysteresis and eddy current losses, while the windings generate heat due to resistance losses. If heat dissipation is not timely, the temperature will rise, directly altering the key physical parameters of these two core components.

[0004] High-precision current transformers often use high-silicon steel sheets or permalloy cores. Their permeability, coercivity, and other parameters are sensitive to temperature. When insufficient heat dissipation causes the core temperature to rise from 25°C to 60°C, the permeability of the high-silicon steel sheets will decrease, while the coercivity will increase. The decrease in permeability will lead to a reduction in the core magnetization efficiency, and the secondary side induced electromotive force will weaken under the same primary side current, resulting in an increase in the ratio error, which will cause distortion of the power metering data and a decrease in the accuracy of the current transformer. Utility Model Content

[0005] To overcome the above deficiencies, this utility model provides a high-precision current transformer for metering, which aims to solve the problem in the prior art that "the accuracy of the current transformer decreases due to temperature rise".

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a high-precision current transformer for metering, comprising a housing, a heat dissipation mechanism on the outer side of the housing, a locking component on the outer side of the heat dissipation mechanism, the heat dissipation mechanism comprising an inner liner, the inner liner comprising two sets, the two sets of the inner liner being attached to the upper outer side of the housing, a heat-conducting sheet b being fixedly connected to the outer arc surface of the inner liner, multiple sets of heat-conducting sheets a being fixedly connected to opposite sides of the two sets of the inner liner, an outer jacket a being fitted to the outer side of the multiple sets of heat-conducting sheets a on the front side, and an outer jacket b being fitted to the outer side of the multiple sets of heat-conducting sheets a on the rear side, the outer jacket a and the outer jacket b being inserted into each other, a fixing shell being fixedly connected to the right side of the outer jacket b, a fan being fixedly connected to the lower part of the fixing shell, the fixing shell communicating with the interior of the outer jacket a and the outer jacket b, and a guide portion being fixedly connected to the inner annular surface of the outer jacket a and the outer jacket b, the guide portion being attached to the outer side of the heat-conducting sheet a.

[0007] As a further description of the above technical solution:

[0008] The locking assembly includes a slide rail, which is fixedly connected to the outside of the outer casing b. A positioning frame is slidably connected to the outside of the slide rail. Multiple sets of connecting parts are fixedly connected to the rear side of the outer casing a. A through groove is provided on the front side of the positioning frame. The connecting parts slide on the inner wall of the positioning frame. A limiting part is fixedly connected to the lower part of the positioning frame. A slot is provided on the inner wall of the limiting part. A protrusion is fixedly connected to the lower outer side of the outer casing. The slot and the protrusion engage with each other.

[0009] As a further description of the above technical solution:

[0010] Both the slide rail and the positioning frame are designed to be arc-shaped.

[0011] As a further description of the above technical solution:

[0012] The limiting part is U-shaped, and an anti-slip groove is provided on the outer side of the limiting part.

[0013] As a further description of the above technical solution:

[0014] The outer side of the protrusion is provided with an arc-shaped surface.

[0015] As a further description of the above technical solution:

[0016] The heat-conducting sheet a is radially distributed around the center point of the inner lining.

[0017] As a further description of the above technical solution:

[0018] The guide portion is deflected toward the side closer to the outer casing.

[0019] As a further description of the above technical solution:

[0020] The cross-section of the slide rail and the connecting part is set to an L shape.

[0021] This utility model has the following beneficial effects:

[0022] 1. In this utility model, two sets of inner linings are tightly attached to the upper outer side of the outer shell, directly contacting the transformer body and quickly conducting the heat generated by the iron core and winding inside the outer shell; the heat-conducting plate b on the outer arc surface and the radially distributed heat-conducting plate a expand the heat dissipation area, and together with the fan at the bottom of the fixed shell, they can continuously input airflow into the channel; and the deflection guide part of the inner ring surface of the outer jacket a and b is attached to the outer side of the heat-conducting plate a, which can guide the airflow to flow evenly through all the heat-conducting plates, avoid local heat accumulation, and ensure the accuracy of the current transformer.

[0023] 2. In this utility model, the connecting part of the outer jacket a can slide into the inner wall through the through groove of the positioning frame, which can quickly achieve auxiliary fixation of the outer jacket a and the outer jacket b, and avoid loosening after plugging and fitting. At the same time, the slot of the inner wall of the limiting part engages with the protrusion at the bottom of the outer shell, which can complete the overall locking of the heat dissipation mechanism and the outer shell, making it convenient for daily inspection and maintenance of the current transformer or individual replacement of the heat dissipation components. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural diagram of the overall device in this utility model;

[0025] Figure 2 This is a bottom view of the three-dimensional structure of the overall device in this utility model;

[0026] Figure 3 This is a three-dimensional structural breakdown diagram of the overall device in this utility model;

[0027] Figure 4 This is a three-dimensional structural disassembly diagram of the locking component in this utility model.

[0028] Legend:

[0029] 1. Outer shell; 2. Heat dissipation mechanism; 21. Inner liner; 22. Heat-conducting plate a; 23. Heat-conducting plate b; 24. Outer jacket a; 25. Outer jacket b; 26. Fixing shell; 27. Fan; 28. Guide part; 3. Locking assembly; 31. Slide rail; 32. Positioning frame; 33. Connecting part; 34. Through groove; 35. Protrusion; 36. Limiting part; 37. Slot. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0031] Reference Figure 1 - Figure 3This utility model provides an embodiment of a high-precision current transformer for metering, comprising a housing 1. The housing 1 is the basic frame of the transformer and serves as a direct protective carrier for the core metering components such as the iron core and windings inside the transformer. A heat dissipation mechanism 2 is provided on the outer side of the housing 1, and a locking component 3 is provided on the outer side of the heat dissipation mechanism 2. The heat dissipation mechanism 2 includes an inner liner 21, and two sets of inner liners 21 are provided. The two sets of inner liners 21 are attached to the upper outer side of the housing 1. The inner liners 21 are made of a good thermal conductor, which can quickly capture the heat conducted by the housing 1 through surface contact and prevent heat from accumulating on the surface of the housing 1. At the same time, the two sets of inner liners 21 are designed to fit the arc contour of the housing 1, ensuring a good fit with the housing 1, reducing the heat conduction gap, and improving the heat transfer efficiency. A heat-conducting plate b23 is fixedly connected to the outer arc surface of the inner lining 21. Multiple sets of heat-conducting plates b23 are provided to diffuse the heat collected by the inner lining 21 to the outside, expanding the initial heat conduction area. Multiple sets of heat-conducting plates a22 are fixedly connected to opposite sides of the two sets of inner lining 21. The heat-conducting plates a22 are radially distributed with respect to the center point of the inner lining 21. The radial distribution design can maximize the expansion of the heat dissipation area and evenly distribute the heat conducted by the inner lining 21 and the heat-conducting plates b23 to the surface of each set of heat-conducting plates a22, avoiding local heat concentration. At the same time, the heat-conducting plates a22 and b23 are made of high thermal conductivity materials, such as aluminum alloy and copper alloy, which can quickly guide heat from the concentrated area to the dispersed area, providing a heat carrier with a large contact area for subsequent active heat dissipation.

[0032] Furthermore, an outer jacket a24 is fitted over the outer side of the multiple sets of heat-conducting fins a22 on the front side, and an outer jacket b25 is fitted over the outer side of the multiple sets of heat-conducting fins a22 on the rear side. The outer jackets a24 and b25 are interlocked to form a complete closed heat dissipation channel, protecting the heat-conducting fins a22 and preventing them from being deformed by external impacts or from being contaminated by dust, thus affecting their thermal conductivity. A directional channel for airflow is constructed to prevent the airflow generated by the fan 27 from diffusing and losing, ensuring that the airflow can be concentrated on the surfaces of the heat-conducting fins a22 and b23. A fixed housing 26 is fixedly connected to the right side of the outer jacket b25, and a fan 27 is fixedly connected to the lower part of the fixed housing 26. The fan 27 continuously inputs external airflow into the fixed housing 26, and the airflow is distributed through the fixed housing 26. Then it enters the closed channel of outer jacket a24 and outer jacket b25, and exchanges heat with the surfaces of heat-conducting plates a22 and b23. Then it is discharged through the guide part 28 between the guide part and the heat-conducting plate a22. The fixed shell 26 is connected to the interior of outer jacket a24 and outer jacket b25. The interior of the fixed shell 26 is hollow, so that the airflow generated by the fan 27 is evenly distributed to the entire heat dissipation channel, avoiding the airflow directly impacting a single area and causing uneven heat dissipation. The inner ring surface of outer jacket a24 and outer jacket b25 is fixedly connected to the guide part 28. The guide part 28 is attached to the outer side of the heat-conducting plate a22. The guide part 28 is deflected to the side closer to the outer shell 1. Through the deflected arc structure, the airflow input by the fan 27 is guided to flow along the radial direction of the heat-conducting plate a22 and discharged.

[0033] Reference Figure 2 - Figure 4 The locking component 3 includes a slide rail 31, which is fixedly connected to the outside of the outer sleeve b25 and serves as the sliding track for the positioning frame 32. The positioning frame 32 is slidably connected to the outside of the slide rail 31. By sliding the positioning frame 32 along the slide rail 31, it achieves docking with the connecting part 33 of the outer sleeve a24. A through slot 34 on the front side of the positioning frame 32 accommodates the connecting part 33 sliding in. When the connecting part 33 is fully inserted into the inner wall of the positioning frame 32, the positioning frame 32 restricts the forward and backward displacement of the connecting part 33, thereby fixing the outer sleeve a24 and the outer sleeve b25. Multiple sets of connecting parts 33 are fixedly connected to the rear side of the outer sleeve a24. When the connecting part 33 slides into the positioning frame 32, it can form an interlocking limit with the positioning frame 32 through its own structure, further preventing the outer sleeve a24 and the outer sleeve b25 from interlocking during operation. During operation, relative displacement occurs, ensuring the airtightness of the heat dissipation channel. A through groove 34 is provided on the front side of the positioning frame 32, the size of which matches the size of the connecting part 33 for easy assembly. The connecting part 33 slides on the inner wall of the positioning frame 32. A limiting part 36 is fixedly connected to the lower part of the positioning frame 32. The limiting part 36 is U-shaped, adapting to the contour of the lower part of the outer shell 1, ensuring that the slot 37 on the inner wall of the limiting part 36 can accurately align with the protrusion 35. The inner wall of the limiting part 36 has a slot 37. When the positioning frame 32 slides to the designated position, the slot 37 can tightly engage with the protrusion 35 on the lower part of the outer shell 1, fixing the heat dissipation mechanism 2 to the outside of the outer shell 1. The lower outer part of the outer shell 1 is fixedly connected to the protrusion 35, and the slot 37 engages with the protrusion 35. Both the slide rail 31 and the positioning frame 32 are arc-shaped; the arc-shaped design reduces the frictional resistance when the slot 37 engages. The limiting part 36 is U-shaped, and an anti-slip groove is provided on the outer side of the limiting part 36 to increase the friction between the operator's hand and the limiting part 36. The outer side of the protrusion 35 is provided with an arc-shaped surface. The cross-section of the slide rail 31 and the connecting part 33 is L-shaped.

[0034] Working principle: In use, firstly, attach the two sets of inner linings 21 to the upper outer side of the outer shell 1 to ensure that the inner linings 21 are in close contact with the outer shell 1; then, put the outer jackets a24 and b25 on the outer side of the two sets of inner linings 21, with the outer jackets a24 and b25 contacting the outer side of the heat-conducting plate a22, and connect the outer jackets a24 and b25 through the plug-in fit to form a closed heat dissipation channel frame. At this time, the guide part 28 is attached to the outer side of the heat-conducting plate a22 to complete the initial positioning, and at the same time, the L-shaped connecting part 33 on the rear side of the outer jacket a24 slides into the inner wall of the positioning frame 32 through the through groove 34 on the front side of the positioning frame 32.

[0035] The positioning frame 32 is pushed to slide along the arc-shaped slide rail 31 on the outer side of the outer jacket b25. The slide rail 31 and the L-shaped cross-section of the connecting part 33 form an interlocking limit to prevent the outer jacket a24 from loosening after being inserted into the outer jacket b25. The positioning frame 32 continues to slide until the groove 37 on the inner wall of the U-shaped limiting part 36 at the bottom of the positioning frame 32 engages with the arc-shaped protrusion 35 at the bottom of the outer shell 1. The arc-shaped surface of the protrusion 35 reduces the engagement resistance, and the anti-slip groove on the outer side of the limiting part 36 makes it easy for the operator to accurately control the force. Finally, the heat dissipation mechanism 2 and the outer shell 1 are fixed together, preventing the heat dissipation components from shifting due to vibration during equipment operation.

[0036] When the current transformer is put into operation, the fan 27 fixed at the lower part of the fixed shell 26 starts and continuously inputs the external low temperature airflow into the hollow fixed shell 26; the fixed shell 26 is connected to the internal channel of the outer jacket a24 and outer jacket b25, and the airflow is evenly distributed to the entire closed heat dissipation channel; at this time, the deflection guide part 28 of the inner ring surface of the outer jacket a24 and outer jacket b25 fits against the outer side of the heat conduction plate a22 to form a directional airflow channel, which carries away the heat on the heat conduction plate a22 and the heat conduction plate b23.

[0037] Finally, it should be noted that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A high-precision current transformer for metering, comprising a housing (1), characterized in that: A heat dissipation mechanism (2) is provided on the outer side of the outer shell (1), and a locking component (3) is provided on the outer side of the heat dissipation mechanism (2). The heat dissipation mechanism (2) includes an inner liner (21), and two sets of the inner liner (21) are provided. The two sets of the inner liner (21) are attached to the upper outer side of the outer shell (1). A heat-conducting plate b (23) is fixedly connected to the outer arc surface of the inner liner (21). Multiple sets of heat-conducting plates a (22) are fixedly connected to opposite sides of the two sets of inner liner (21). An outer jacket a (24) is fitted on the outer side of the multiple sets of heat-conducting plates a (22) on the front side. A jacket b (25) is fitted on the outer side of the multiple sets of heat-conducting plates a (22). The jacket a (24) and the jacket b (25) are inserted into each other. A fixed shell (26) is fixedly connected to the right side of the jacket b (25). A fan (27) is fixedly connected to the lower part of the fixed shell (26). The fixed shell (26) communicates with the interior of the jacket a (24) and the jacket b (25). A guide part (28) is fixedly connected to the inner ring surface of the jacket a (24) and the jacket b (25). The guide part (28) is attached to the outer side of the heat-conducting plate a (22).

2. The high-precision current transformer for metering according to claim 1, characterized in that: The locking component (3) includes a slide rail (31), which is fixedly connected to the outside of the outer casing b (25). A positioning frame (32) is slidably connected to the outside of the slide rail (31). Multiple connecting parts (33) are fixedly connected to the rear side of the outer casing a (24). A through groove (34) is provided on the front side of the positioning frame (32). The connecting part (33) slides on the inner wall of the positioning frame (32). A limiting part (36) is fixedly connected to the lower part of the positioning frame (32). A slot (37) is provided on the inner wall of the limiting part (36). A protrusion (35) is fixedly connected to the lower outer side of the outer casing (1). The slot (37) and the protrusion (35) engage with each other.

3. A high-precision current transformer for metering according to claim 2, characterized in that: Both the slide rail (31) and the positioning frame (32) are set to be arc-shaped.

4. A high-precision current transformer for metering according to claim 2, characterized in that: The limiting part (36) is U-shaped, and an anti-slip groove is provided on the outer side of the limiting part (36).

5. A high-precision current transformer for metering according to claim 2, characterized in that: The outer side of the protrusion (35) is provided with an arc-shaped surface.

6. A high-precision current transformer for metering according to claim 1, characterized in that: The heat-conducting sheet a (22) is radially distributed around the center point of the liner (21).

7. A high-precision current transformer for metering according to claim 1, characterized in that: The guide portion (28) is deflected toward the side closer to the outer casing (1).

8. A high-precision current transformer for metering according to claim 2, characterized in that: The cross-section of the slide rail (31) and the connecting part (33) is set to an L shape.

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