A compact current transformer resistant to electromagnetic interference
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-20
- Publication Date
- 2026-08-14
AI Technical Summary
[0005]针对现有技术的不足，本实用新型提供了一种抗电磁干扰的紧凑型电流互感器，解决了现有装置通常缺乏地线出口导向功能，在实际安装过程中，由于电流互感器的安装空间有限，且周围设备布局复杂，地线往往难以找到理想的出线路径，安装人员为了迁就空间限制和连接需求，常常不得不将地线以较为生硬的角度引出，这就容易导致地线出现接近九十度的弯折，而这种接近九十度的弯折，会使得地线外端线体护套在长期使用过程中，受到来自弯折处的持续应力作用，从而加剧外端线体护套的磨损速度，一旦线体护套磨损严重，就可能引发漏电等安全隐患，影响电力系统的正常运行和人员安全的技术问题
一、通过缺口圆环座对接地线本体出线端的套接，在向外拉动接地线本体进行接线操作时，接地线本体将与弧面导向槽圆弧倾斜表面接触，从而避免接地线本体线头过度弯折，且确保接地线本体连接可靠，提高设备整体可靠性与安全性，保障电力系统稳定运行。
Smart Images
Figure CN224637055U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of current transformer technology, and in particular to a compact current transformer that is resistant to electromagnetic interference. Background Technology
[0002] In power systems, compact current transformers resistant to electromagnetic interference play a crucial role in ensuring the stable operation of power equipment and the accurate measurement of power parameters. They are widely used in various substations, distribution rooms, and industrial power applications to accurately measure large currents in circuits and provide reliable current signals for relay protection devices, while simultaneously resisting interference from complex external electromagnetic environments. Currently, compact current transformers resistant to electromagnetic interference typically require the following technologies in practical applications: 1. High-efficiency electromagnetic shielding technology: It can effectively resist interference from external electromagnetic fields, ensuring that the current transformer can still work accurately in complex electromagnetic environments, and guaranteeing measurement accuracy and signal transmission stability. 2. Compact structural design technology: While meeting electrical performance requirements, the size and weight of the instrument transformer are minimized by optimizing the design of components such as the core, windings, and housing to adapt to the needs of different installation spaces; 3. Reliable grounding technology: Ensures a stable grounding wire connection, reliably introduces current into the earth, avoids safety hazards caused by poor grounding, and ensures the normal operation of the current transformer.
[0003] Currently, various types of current transformers and related technologies are used in the market to achieve electromagnetic interference resistance and compact design. Some products improve electromagnetic shielding performance and compactness by modifying core materials and winding processes; others focus on optimizing the casing design, using integrated molding technology to reduce the number of components and achieve a compact layout. Still other products innovate in grounding methods, such as using new grounding terminals or connection structures to enhance grounding reliability.
[0004] However, these methods have a prominent problem: existing devices usually lack ground wire outlet guidance. In actual installation, due to the limited installation space of the current transformer and the complex layout of surrounding equipment, it is often difficult to find an ideal outlet path for the ground wire. In order to accommodate space constraints and connection requirements, installers often have to lead the ground wire out at a relatively abrupt angle, which can easily lead to a near 90-degree bend in the ground wire. This near 90-degree bend will cause the outer end sheath of the ground wire to be subjected to continuous stress from the bend during long-term use, thereby accelerating the wear rate of the outer end sheath. Once the sheath is severely worn, it may cause safety hazards such as leakage, affecting the normal operation of the power system and personnel safety. Utility Model Content
[0005] To address the shortcomings of existing technologies, this utility model provides a compact current transformer with electromagnetic interference resistance. It solves the problem that existing devices typically lack a ground wire outlet guidance function. In actual installation, due to limited installation space and complex surrounding equipment layout, it is often difficult to find an ideal outlet path for the ground wire. To accommodate space constraints and connection requirements, installers often have to lead the ground wire out at a relatively abrupt angle, easily resulting in a near-90-degree bend. This near-90-degree bend causes the outer sheath of the ground wire to be subjected to continuous stress at the bend during long-term use, thus accelerating the wear rate of the outer sheath. Once the sheath is severely worn, it may cause safety hazards such as leakage, affecting the normal operation of the power system and personnel safety.
[0006] To achieve the above objectives, this utility model provides the following technical solution: A compact current transformer resistant to electromagnetic interference includes a current transformer body. A U-shaped bracket is provided on the outer surface of the current transformer body. A notched annular seat is fixedly connected to the lower end of the U-shaped bracket. An arc-shaped guide groove is formed inside the notched annular seat. A round rod shaft is rotatably connected inside the notched annular seat. An inlet baffle is sleeved on the outer surface of the round rod shaft. A torsion spring is sleeved on the outer surface of the round rod shaft. The torsion spring is sleeved inside the notched annular seat.
[0007] Preferably, both the U-shaped bracket and the current transformer body are internally threaded with bracket mounting bolts, and the current transformer body is internally threaded with a ground wire tightening bolt.
[0008] Preferably, the grounding wire body is provided on the outer surface of the grounding wire clamping bolt, and the grounding wire body and the outer surface of the current transformer body are in contact.
[0009] Preferably, a current transformer mounting bolt is provided at one end of the current transformer body near the bracket mounting bolt, and an arc-shaped reinforcing ring is fixedly connected to the inner surface of the U-shaped bracket.
[0010] Preferably, the arc-shaped reinforcing ring and the notched annular seat are on the same vertical line, and a rubber contact pad is fixedly connected to the inner surface of the arc-shaped reinforcing ring.
[0011] Preferably, the rubber contact pad and the outer surface of the grounding wire body are in contact, and a loop conductor is provided inside the current transformer body.
[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. By connecting the grounding wire body to the outlet end of the grounding wire body through the notched circular seat, when the grounding wire body is pulled outward for wiring operations, the grounding wire body will contact the arc-shaped inclined surface of the arc guide groove, thereby avoiding excessive bending of the grounding wire body end and ensuring reliable connection of the grounding wire body, improving the overall reliability and safety of the equipment, and ensuring the stable operation of the power system.
[0013] 2. After the grounding wire body is connected, attach the U-shaped bracket and the wiring point on the outer surface of the current transformer body. The arc-shaped reinforcing ring installed on the inner surface of the U-shaped bracket is used to press against the output end of the grounding wire body. The rubber contact pad adhered to the inner surface of the arc-shaped reinforcing ring will be in contact with the surface of the grounding wire body. The cooperation between the rubber contact pad and the grounding wire tightening bolt provides double protection for the installation of the grounding wire body and ensures the stability of its connection. Attached Figure Description
[0014] The above description is only an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings.
[0015] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is an exploded view of the U-shaped bracket connection of this utility model; Figure 3 This is an exploded view of the rubber contact pad connection of this utility model; Figure 4 This is an exploded view of the entrance baffle connection of this utility model.
[0016] Legend: 11. Current transformer body; 12. U-shaped bracket; 13. Notched annular seat; 14. Arc-shaped guide groove; 15. Round rod shaft; 16. Inlet baffle; 17. Torsion spring; 18. Bracket mounting bolt; 19. Grounding wire tightening bolt; 21. Grounding wire body; 22. Current transformer mounting bolt; 23. Arc-shaped reinforcing ring; 24. Rubber contact pad; 25. Circuit conductor. Detailed Implementation
[0017] This application provides a compact current transformer with electromagnetic interference resistance, effectively solving the problem that existing devices often lack ground wire outlet guidance functions. In actual installation, due to limited installation space and complex surrounding equipment layout, it is often difficult to find an ideal outlet path for the ground wire. To accommodate space constraints and connection requirements, installers often have to lead the ground wire out at a relatively abrupt angle, which can easily lead to a near-90-degree bend. This near-90-degree bend causes the outer sheath of the ground wire to be subjected to continuous stress from the bend during long-term use, thus accelerating the wear rate of the outer sheath. Once the sheath is severely worn, it may cause safety hazards such as leakage, affecting the normal operation of the power system and personnel safety. By using a notched annular seat to connect the outlet end of the ground wire body, when pulling the ground wire body outward for wiring operations, the ground wire body will contact the arc-shaped inclined surface of the arc guide groove, thereby avoiding excessive bending of the ground wire body end and ensuring reliable connection of the ground wire body, improving the overall reliability and safety of the equipment, and ensuring the stable operation of the power system. Example
[0018] like Figure 1-4As shown, the technical solution in this application embodiment effectively solves the problem that existing devices often lack ground wire outlet guidance function. In actual installation, due to the limited installation space of the current transformer and the complex layout of surrounding equipment, it is often difficult to find an ideal outlet path for the ground wire. In order to accommodate space constraints and connection requirements, installers often have to lead the ground wire out at a relatively abrupt angle, which can easily lead to a near 90-degree bend in the ground wire. This near 90-degree bend will cause the outer end sheath of the ground wire to be subjected to continuous stress from the bend during long-term use, thereby accelerating the wear rate of the outer end sheath. Once the sheath is severely worn, it may cause safety hazards such as leakage, affecting the normal operation of the power system and personnel safety. The overall idea is as follows: A compact current transformer with electromagnetic interference resistance includes a current transformer body 11. A U-shaped bracket 12 is provided on the outer surface of the current transformer body 11. A notched annular seat 13 is fixedly connected to the lower end of the U-shaped bracket 12. An arc-shaped guide groove 1 is opened inside the notched annular seat 13. 4. A round rod shaft 15 is rotatably connected inside the notched annular seat 13. An inlet baffle 16 is sleeved on the outer surface of the round rod shaft 15, and a torsion spring 17 is sleeved on the outer surface of the round rod shaft 15. The torsion spring 17 is sleeved inside the notched annular seat 13. When the arc-shaped reinforcing ring 23 abuts against the grounding wire body 21 for fixing, the surface of the grounding wire body 21 will first contact the surface of the inlet baffle 16 and push the inlet baffle 16 to rotate into the notched annular seat 13. When the notched annular seat 13 rotates, it will compress the torsion spring 17 and contract. When the grounding wire body 21... After fully entering the notched annular seat 13, the inlet baffle 16 loses external force and will rotate and reset under the elastic force of the torsion spring 17. Through the notched annular seat 13 connecting the outlet end of the grounding wire body 21, when the grounding wire body 21 is pulled outward for wiring operation, the grounding wire body 21 will contact the arc inclined surface of the arc guide groove 14, thereby avoiding excessive bending of the wire end of the grounding wire body 21 and ensuring reliable connection of the grounding wire body 21, improving the overall reliability and safety of the equipment, and ensuring the stable operation of the power system.
[0019] Both the U-shaped bracket 12 and the current transformer body 11 are internally threaded with bracket mounting bolts 18. The current transformer body 11 is internally threaded with a grounding bolt 19. A grounding wire body 21 is mounted on the outer surface of the grounding bolt 19, and the grounding wire body 21 is in contact with the outer surface of the current transformer body 11. A transformer mounting bolt 22 is located at one end of the current transformer body 11 near the bracket mounting bolts 18. The current transformer body 11 utilizes a permalloy core with high permeability and good magnetic shielding performance to reduce the influence of external electromagnetic fields on the internal magnetic field. To mitigate electromagnetic interference, the transformer employs multiple layers of electromagnetic shielding. An inner metal shield protects against electric field interference, a middle magnetic shield protects against magnetic field interference, and an outer insulating layer protects against environmental influences. Structurally, the transformer core utilizes a high-performance microcrystalline alloy material with high permeability and low loss characteristics. This allows for a smaller core size while maintaining electrical performance. The windings employ a tight-winding technique, optimizing the combination of turns and wire diameter to efficiently arrange the windings within a limited space, significantly reducing the space occupied by the windings. Simultaneously, the transformer's outer casing... The integrated design consolidates previously scattered components, reducing unnecessary space waste. Within the current transformer body 11, the grounding wire body 21 is secured by tightening the grounding bolt 19, achieving grounding connection through the grounding wire body 21. The current transformer body 11 is installed in the power system by tightening the transformer mounting bolt 22. The current transformer body 11 plays a crucial role in the power system, providing measurement, protection, and facilitating standardized design of secondary equipment. During operation, the primary winding is connected in series in the circuit under test. When a large current flows through... During secondary winding, an alternating magnetic flux is generated in the iron core. According to the law of electromagnetic induction, the secondary winding in the alternating magnetic field will induce a secondary current proportional to its number of turns. By connecting the current transformer body 11 to an external measuring instrument, the current transformer body 11 can convert the large current into a small current in a specific ratio, so that the measuring instrument can accurately measure the current value. It can also be used in conjunction with other measuring equipment to measure various power parameters. When a system fault causes an abnormal current, it provides a signal to the relay protection device, so that it can quickly act to disconnect the faulty line, and at the same time play an electrical isolation role to ensure safety.
[0020] An arc-shaped reinforcing ring 23 is fixedly connected to the inner surface of the U-shaped bracket 12. The arc-shaped reinforcing ring 23 and the notched annular seat 13 are on the same vertical line. A rubber contact pad 24 is fixedly connected to the inner surface of the arc-shaped reinforcing ring 23. The rubber contact pad 24 is in contact with the outer surface of the grounding wire body 21. A loop conductor 25 is provided inside the current transformer body 11. A wire end protection device composed of the U-shaped bracket 12, the notched annular seat 13, the arc-shaped guide groove 14 opened in the notched annular seat 13, the arc-shaped reinforcing ring 23, and the rubber contact pad 24 is provided on the outer surface of the grounding wire body 21. After the grounding wire body 21 is connected, the U-shaped bracket 12 and the current transformer are connected. The wiring terminals on the outer surface of the transformer body 11 are fitted together. The shape of the U-shaped bracket 12 is compatible with the surface of the current transformer body 11. After pressing and fitting together, the arc-shaped reinforcing ring 23 installed on the inner surface of the U-shaped bracket 12 presses against the output end of the grounding wire body 21. The rubber contact pad 24 bonded to the inner surface of the arc-shaped reinforcing ring 23 will fit against the surface of the grounding wire body 21. The rubber material of the arc-shaped reinforcing ring 23 and the rubber contact pad 24 will further reinforce the contact without affecting the performance and conductivity of the grounding wire body 21. The cooperation between the rubber contact pad 24 and the grounding wire tightening bolt 19 provides double insurance for the installation of the grounding wire body 21, ensuring the stability of its connection.
[0021] To address the problems existing in the prior art, this utility model provides a compact current transformer that resists electromagnetic interference. By connecting the grounding wire body 21 to the output end through the notched annular seat 13, when the grounding wire body 21 is pulled outward for wiring operations, the grounding wire body 21 will contact the arc-shaped inclined surface of the arc guide groove 14, thereby avoiding excessive bending of the wire end of the grounding wire body 21 and ensuring reliable connection of the grounding wire body 21, improving the overall reliability and safety of the equipment, and ensuring the stable operation of the power system.
[0022] Working principle: The first step involves using a permalloy core with high permeability and good magnetic shielding performance in the current transformer body 11 to reduce the influence of external electromagnetic fields on the internal magnetic field. Multiple electromagnetic shielding layers are installed externally: an inner metal shielding layer to shield electric field interference, a middle magnetic shielding layer to shield magnetic field interference, and an outer insulating protective layer to protect against environmental influences, thus achieving electromagnetic interference resistance. In terms of structural layout, the transformer core uses a high-performance microcrystalline alloy material with high permeability and low loss characteristics. This material can reduce the core volume while meeting electrical performance requirements. The windings employ a tight winding technique, optimizing the combination of winding turns and wire diameter to efficiently arrange the windings within a limited space, significantly reducing the space occupied by the windings. Simultaneously, the transformer casing is designed as an integrated unit, consolidating previously scattered components and reducing unnecessary space waste. Inside the current transformer body 11, the grounding wire body 21 is secured by tightening the grounding wire clamping bolt 19. Grounding is achieved through the grounding wire body 21. The current transformer body 11 is installed in the circuit system by tightening the transformer mounting bolts 22. The current transformer body 11 plays a crucial role in the power system, including measurement, protection, and facilitating the standardized design of secondary equipment. During operation, the primary winding is connected in series in the circuit under test. When a large current passes through the primary winding, an alternating magnetic flux is generated in the iron core. According to the law of electromagnetic induction, the secondary winding in the alternating magnetic field will induce a secondary current proportional to its number of turns. By connecting the current transformer body 11 to an external measuring instrument, the current transformer body 11 transforms the large current into a small current according to a specific ratio, allowing the measuring instrument to accurately measure the current value. It can also be used in conjunction with other measuring equipment to measure various power parameters. When a system fault causes an abnormal current, it provides a signal to the relay protection device, enabling it to quickly disconnect the faulty line, while also providing electrical isolation to ensure safety.
[0023] The second step involves installing a wire end protection device on the outer surface of the grounding wire body 21, consisting of a U-shaped bracket 12, a notched annular seat 13, an arc-shaped guide groove 14 within the notched annular seat 13, an arc-shaped reinforcing ring 23, and a rubber contact pad 24. After the grounding wire body 21 is connected, the U-shaped bracket 12 and the wiring joint on the outer surface of the current transformer body 11 are attached. The shape of the U-shaped bracket 12 matches the surface of the current transformer body 11. After pressing and attaching, the arc-shaped reinforcing ring 23 installed on the inner surface of the U-shaped bracket 12 presses against the outlet end of the grounding wire body 21. The rubber contact pad 24 adhered to the inner surface of the arc-shaped reinforcing ring 23 will adhere to the surface of the grounding wire body 21. The rubber material of the arc-shaped reinforcing ring 23 and the rubber contact pad 24 will further reinforce the grounding wire body 21 without affecting its performance and conductivity. The cooperation between the rubber contact pad 24 and the grounding wire tightening bolt 19 further reinforces the grounding wire body 21. The installation of 1 provides double insurance to ensure the stability of its connection. When the arc-shaped reinforcing ring 23 is fixed against the grounding wire body 21, the surface of the grounding wire body 21 will first contact the surface of the inlet baffle 16 and push the inlet baffle 16 to rotate into the notched annular seat 13. When the notched annular seat 13 rotates, it will compress the torsion spring 17 to contract. When the grounding wire body 21 is completely inside the notched annular seat 13, the inlet baffle 16 loses the external force and will rotate back to its original position under the elastic force of the torsion spring 17. Through the notched annular seat 13 connecting the output end of the grounding wire body 21, when the grounding wire body 21 is pulled outward for wiring, the grounding wire body 21 will contact the arc-shaped inclined surface of the arc-shaped guide groove 14, thereby avoiding excessive bending of the wire end of the grounding wire body 21 and ensuring reliable connection of the grounding wire body 21, improving the overall reliability and safety of the equipment, and ensuring the stable operation of the power system.
[0024] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.
Claims
1. A compact current transformer resistant to electromagnetic interference, comprising a current transformer body (11), wherein a U-shaped bracket (12) is provided on the outer surface of the current transformer body (11), characterized in that, The lower end of the U-shaped bracket (12) is fixedly connected to a notched annular seat (13), and an arc-shaped guide groove (14) is opened inside the notched annular seat (13). A round rod shaft (15) is rotatably connected inside the notched annular seat (13), and an inlet baffle (16) is sleeved on the outer surface of the round rod shaft (15). Among them, a torsion spring (17) is sleeved on the outer surface of the round rod shaft (15), and the torsion spring (17) is sleeved inside the notched annular seat (13).
2. The compact current transformer with electromagnetic interference suppression as described in claim 1, characterized in that, Both the U-shaped bracket (12) and the current transformer body (11) are internally threaded with bracket mounting bolts (18). The current transformer body (11) is internally threaded with a ground wire clamping bolt (19).
3. A compact current transformer with electromagnetic interference suppression as described in claim 2, characterized in that, The grounding wire body (21) is provided on the outer surface of the grounding wire clamping bolt (19). The outer surfaces of the grounding wire body (21) and the current transformer body (11) are attached to each other.
4. A compact current transformer with electromagnetic interference suppression as described in claim 3, characterized in that, A current transformer mounting bolt (22) is provided at one end of the current transformer body (11) near the bracket mounting bolt (18). Among them, the inner surface of the U-shaped bracket (12) is fixedly connected with an arc-shaped reinforcing ring (23).
5. A compact current transformer with electromagnetic interference suppression as described in claim 4, characterized in that, The arc-shaped reinforcing ring (23) and the notched circular seat (13) are on the same vertical line; Among them, the inner surface of the arc-shaped reinforcing ring (23) is fixedly connected with a rubber contact pad (24).
6. A compact current transformer with electromagnetic interference suppression as described in claim 5, characterized in that, The rubber contact pad (24) and the outer surface of the grounding wire body (21) are in contact; The current transformer body (11) is provided with a loop conductor (25).