Current transformer with protection structure

Abstract

The utility model belongs to current transformer technical field, and disclose a current transformer with protection structure, including installation shell, the top of installation shell is equipped with the shell cover, the inner surface of installation shell is equipped with three base, the base is annular, the outer surface of base is sleeved and has the induction unit, the induction unit is composed of annular magnetic core and secondary winding, the outer surface of base is slidably connected and has the reinforcing ring, the utility model discloses a reinforcing rod, reset spring and bottom hollow round table -shaped reinforcing ring are arranged, under the elastic pre -compression effect of reset spring, reinforcing rod can continuously exert axial pressure to reinforcing ring, make the round table -shaped structure of reinforcing ring tightly fill the gap between induction unit and base, effectively limit the relative sway of induction unit and base, solved the magnetic circuit instability problem of existing device because of the gap, guarantee the core working precision of current transformer.

Description

Technical Field

[0001] This utility model belongs to the field of current transformer technology, specifically a current transformer with a protection structure. Background Technology

[0002] In modern power systems, current transformers, as critical electrical equipment, play a vital role in converting high-voltage, high-current circuits into low-voltage, low-current signals. They provide accurate and reliable current information for power metering, relay protection, and system monitoring, serving as a fundamental component for ensuring the safe, stable, and economical operation of the power system. As power systems continue to evolve towards higher voltage, larger capacity, and smarter operation, the application scenarios for current transformers are becoming increasingly complex, and the external environmental influences and internal operating challenges they face during operation are also increasing. To further improve the reliability and safety of current transformers in practical applications, ensuring their stable functioning during long-term service and meeting the stringent performance requirements of power systems for critical equipment, a current transformer with a protective structure has emerged.

[0003] Meanwhile, the patent specification with application number CN218849253U discloses a current transformer with a fast circuit breaking protection structure, "including a mounting base and a current transformer housing. The current transformer housing is fixed at the middle position of the upper end of the mounting base. The current transformer housing has a U-shaped structure. A U-shaped groove is provided inside the current transformer housing. Iron cores are installed on both sides of the U-shaped groove. Coils with different numbers of turns are wound on the iron cores respectively. A pair of terminals are installed on both sides of the current transformer housing."

[0004] When existing current transformers are in long-term operation or are affected by vibration, the relative displacement between the internal sensing unit and the base is prone to occur due to the assembly gap, which leads to a decrease in magnetic circuit stability, thereby affecting the current conversion accuracy and even causing the protection device to malfunction.

[0005] Therefore, a current transformer with a protection structure is proposed to address the above problems. Utility Model Content

[0006] To address the problems mentioned in the background art, this utility model provides a current transformer with a protective structure, which solves the problem of magnetic circuit instability caused by gaps in existing devices, ensures the core working accuracy of the current transformer, extends the overall service life of the device, and forms a dual protection system together with the reinforcement components.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a current transformer with a protective structure, comprising a mounting housing, a housing cover at the top of the mounting housing, three bases on the inner surface of the mounting housing, the bases being annular, an induction unit sleeved on the outer surface of the bases, the induction unit being composed of an annular magnetic core and a secondary winding, a reinforcing ring slidably wound on the outer surface of the bases, the reinforcing ring being located above the induction unit, three fixing rings fixedly connected to the top of the housing cover, three reinforcing rods slidably connected to the inner surface of the fixing rings, a return spring wound on the outer surface of the reinforcing rods, a reinforcing plate fixedly connected to the bottom end of the return springs, the inner surface of the reinforcing plate being fixedly sleeved with the outer surface of the reinforcing rods, and the bottom end of the reinforcing rod penetrating the housing cover and fitting against the top of the reinforcing ring.

[0008] Preferably, the top end of the reinforcing rod passes through a fixing ring and is fixedly connected to an anti-detachment block.

[0009] Preferably, the bottom end of the reinforcing ring is in the shape of a hollow frustum, so that the reinforcing ring can be adapted to fill the gap between the sensing unit and the base.

[0010] Preferably, the three fixing rings are respectively aligned with the centers of the three bases on the same vertical line.

[0011] Preferably, four hollow positioning sleeve rods are fixedly connected to the lower inner wall of the mounting housing, and four positioning rods that cooperate with the four hollow positioning sleeve rods are fixedly connected to the upper inner wall of the housing cover. The positioning rods and the hollow positioning sleeve rods are connected by an interference fit.

[0012] Preferably, a sealing ring is provided at the top of the mounting housing and at the edge corresponding to the housing cover.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0014] 1. This utility model, by setting a reinforcing rod, a return spring, and a reinforcing ring with a hollow frustum shape at the bottom, allows the reinforcing rod to continuously apply axial pressure to the reinforcing ring under the elastic preload of the return spring. This causes the frustum-shaped structure of the reinforcing ring to tightly fill the gap between the sensing unit and the base, effectively limiting the relative sway between the sensing unit and the base. This solves the problem of magnetic circuit instability caused by gaps in existing devices and ensures the core working accuracy of the current transformer.

[0015] 2. By setting up a hollow positioning sleeve and a positioning rod, this utility model can not only achieve quick and accurate alignment of the mounting housing and the cover under the action of their interlocking, avoiding the squeezing damage to the internal structure caused by assembly deviation; at the same time, the interference fit structure can also enhance the connection and sealing of the mounting housing and the cover, reduce the intrusion of external dust, moisture and other impurities, further protect the core components such as the sensing unit, extend the overall service life of the device, and build a dual protection system together with the reinforcement components. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0017] Figure 2 This is an exploded view of the housing and cover structure of this utility model;

[0018] Figure 3 This utility model Figure 2 Enlarged schematic diagram of the structure at point A in the middle;

[0019] Figure 4 This is a schematic diagram of the shell cover structure of this utility model;

[0020] Figure 5 This is a schematic diagram of the reinforcing ring structure of this utility model.

[0021] In the diagram: 1. Mounting housing; 11. Base; 12. Sensing unit; 13. Reinforcing ring; 14. Hollow positioning sleeve; 141. Positioning rod; 15. Sealing ring;

[0022] 2. Shell cover;

[0023] 3. Fixing ring; 31. Anti-detachment block; 32. Return spring; 33. Reinforcing plate; 34. Reinforcing rod. Detailed Implementation

[0024] 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.

[0025] like Figures 1 to 5 As shown, this utility model provides a current transformer with a protective structure, including a mounting housing 1, a cover 2 at the top of the mounting housing 1, three bases 11 on the inner surface of the mounting housing 1, the bases 11 being annular, and an induction unit 12 sleeved on the outer surface of the bases 11.

[0026] The sensing unit 12 consists of a ring magnetic core and a secondary winding. A reinforcing ring 13 is slidably wound on the outer surface of the base 11, and the reinforcing ring 13 is located above the sensing unit 12.

[0027] Three fixing rings 3 are fixedly connected to the top of the housing 2. Three reinforcing rods 34 are slidably connected to the inner surface of the fixing rings 3. A return spring 32 is wound around the outer surface of the reinforcing rod 34. A reinforcing plate 33 is fixedly connected to the bottom end of the return spring 32. The inner surface of the reinforcing plate 33 is fixedly sleeved with the outer surface of the reinforcing rod 34. The bottom end of the reinforcing rod 34 passes through the housing 2 and fits against the top of the reinforcing ring 13. By installing the three annular bases 11 inside the housing 1 to position the sensing unit 12, combined with the reinforcing structure composed of the reinforcing rods 34, the return springs 32 and the reinforcing plate 33, the reinforcing rods 34 can continuously apply stable pressure to the reinforcing ring 13, indirectly fixing the sensing unit 12 firmly on the base 11, preventing the sensing unit 12 from displacing due to equipment vibration, ensuring the stability of the connection between the sensing unit 12 and the base 11, and laying a structural foundation for the current transformer to accurately realize current conversion.

[0028] Specifically, the top end of the reinforcing rod 34 passes through the fixing ring 3 and is fixedly connected to an anti-detachment block 31. The anti-detachment block 31 at the top end of the reinforcing rod 34 can limit the sliding range of the reinforcing rod 34 within the fixing ring 3, preventing the reinforcing rod 34 from falling out of the fixing ring 3 due to the elastic reset of the return spring 32 or the impact during equipment operation.

[0029] like Figures 1 to 5 As shown, the bottom end of the reinforcing ring 13 is in the shape of a hollow frustum, which allows the reinforcing ring 13 to fit into the gap between the sensing unit 12 and the base 11. The hollow frustum design of the bottom end of the reinforcing ring 13 can precisely fit the shape of the gap between the sensing unit 12 and the base 11. Under the downward pressure of the reinforcing rod 34, the gap can be completely filled, eliminating the loose space between the sensing unit 12 and the base 11 and reducing the impact of vibration on the sensing unit 12.

[0030] Furthermore, the three fixing rings 3 are aligned with the centers of the three bases 11 on the same vertical line. This design ensures that the pressure of the reinforcing rod 34 on the reinforcing ring 13 is accurately transmitted to the sensing unit 12 in the vertical direction. This avoids uneven force on the sensing unit 12 due to pressure direction deviation, which could lead to tilting or deformation. At the same time, it ensures that the three sensing units 12 are subjected to the same force, thereby improving the overall balance and stability of the device.

[0031] like Figures 1 to 5As shown, four hollow positioning sleeve rods 14 are fixedly connected to the lower inner wall of the mounting housing 1, and four positioning rods 141 that cooperate with the four hollow positioning sleeve rods 14 are fixedly connected to the upper inner wall of the cover 2. The positioning rods 141 and the hollow positioning sleeve rods 14 are connected by an interference fit, which can quickly achieve precise alignment between the mounting housing 1 and the cover 2, reduce assembly difficulty and improve assembly efficiency. The tight connection of the interference fit can enhance the connection strength between the mounting housing 1 and the cover 2, prevent the cover 2 from loosening during equipment operation, and ensure the stability of the overall structure of the device. Alternatively, after the mounting housing 1 and the cover 2 are initially fixed, liquid resin can be poured onto the edge. After the resin solidifies, the mounting housing 1 and the cover 2 can be further firmly fixed.

[0032] It is worth noting that a sealing ring 15 is provided at the top of the mounting housing 1 and the edge corresponding to the cover 2. The sealing ring 15 at the edge of the mounting housing 1 and the cover 2 can effectively prevent dust, moisture and other impurities in the external environment from entering the interior of the mounting housing 1, avoid impurities from adhering to the surface of the secondary winding of the sensing unit 12 or entering the gap of the annular magnetic core, prevent impurities from causing a decrease in the insulation performance of the secondary winding or obstruction of the magnetic core circuit, extend the service life of the sensing unit 12, and improve the protection performance of the device.

[0033] Working principle and process: When the current transformer is working, the primary side high-current conductor passes through the annular center of the base 11 inside the mounting housing 1, and the primary side current generates alternating magnetic flux in the annular magnetic core. Since the secondary winding is wound on the annular magnetic core, according to the principle of electromagnetic induction, the secondary winding will induce a small current with a fixed transformation ratio to the primary side current. During the operation of the device, the reinforcing rod 34, the return spring 32, the reinforcing ring 13, etc., ensure that the sensing unit 12 and the base 11 are tightly fitted through stable pressure, avoiding magnetic circuit loss due to displacement of the sensing unit 12; the interference fit of the hollow positioning sleeve rod 14 and the positioning rod 141 ensures precise docking between the mounting housing 1 and the cover 2, and the sealing ring 15 prevents external impurities from entering, together creating a stable and clean working environment for the sensing unit 12, ultimately enabling the small current induced by the secondary winding to be accurately transmitted to external measuring instruments or protection devices, realizing the measurement of the primary side high current and circuit protection functions.

[0034] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A current transformer with a protective structure, comprising a mounting housing (1), characterized in that: The top of the mounting housing (1) is provided with a cover (2), and the inner surface of the mounting housing (1) is provided with three bases (11). The bases (11) are annular, and the outer surface of the bases (11) is fitted with a sensing unit (12). The sensing unit (12) is composed of an annular magnetic core and a secondary winding. The outer surface of the bases (11) is slidably wound with a reinforcing ring (13), and the reinforcing ring (13) is located above the sensing unit (12). The top of the cover (2) is fixedly connected with three fixing rings (3), and the inner surface of the fixing rings (3) is slidably connected with three reinforcing rods (34). The outer surface of the reinforcing rods (34) is wound with a return spring (32), and the bottom end of the return spring (32) is fixedly connected with a reinforcing plate (33). The inner surface of the reinforcing plate (33) is fixedly sleeved with the outer surface of the reinforcing rod (34), and the bottom end of the reinforcing rod (34) penetrates the cover (2) and fits against the top of the reinforcing ring (13).

2. The current transformer with protective structure according to claim 1, characterized in that: The top end of the reinforcing rod (34) passes through the fixing ring (3) and is fixedly connected to the anti-detachment block (31).

3. The current transformer with protective structure according to claim 1, characterized in that: The bottom end of the reinforcing ring (13) is in the shape of a hollow frustum, so that the reinforcing ring (13) can be adapted to fill the gap between the sensing unit (12) and the base (11).

4. The current transformer with protective structure according to claim 1, characterized in that: The three fixed rings (3) are on the same vertical line as the centers of the three bases (11).

5. The current transformer with protective structure according to claim 1, characterized in that: The lower inner wall of the mounting housing (1) is fixedly connected with four hollow positioning sleeves (14), and the upper inner wall of the cover (2) is fixedly connected with four positioning rods (141) that cooperate with the four hollow positioning sleeves (14). The positioning rods (141) and the hollow positioning sleeves (14) are connected by an interference fit.

6. A current transformer with protective structure according to claim 5, characterized in that: A sealing ring (15) is provided at the top of the mounting housing (1) and at the edge corresponding to the cover (2).

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