Zero sequence current transformer

Abstract

The invention discloses a zero sequence current transformer which comprises a transformer module which is an open-close type zero sequence current transformer, the transformer module is provided with a front assembly, a rear assembly and an angle iron piece for locking the front assembly and the rear assembly which are combined, the front assembly and the rear assembly are both U-shaped iron core knots and are arranged in a mirror image mode, and movable strips are arranged on the front sides of the front assembly and the rear assembly. The angle iron pieces are distributed on the outer sides of the front assembly and the rear assembly and locked through bolts, and a rectangular iron core channel is formed between the front assembly and the rear assembly. The integrated base is used for locking and mounting the mutual inductor module and providing protection, the integrated base comprises a bottom frame seat, a protective outer frame and a locking structure, mounting edges are arranged on the two sides of the bottom of the bottom frame seat, an opening is formed in the top surface of the bottom frame seat, and through penetrating holes are formed in the two sides of the top of the bottom frame seat. Through the rectangular opening and closing type design, an innovative modular structure and an integrated base are combined, and the cable connector is more suitable for parallel connection of a large-section single-core cable and two cables.

Description

Technical Field

[0001] The invention relates to the field of current transformers in power systems, in particular to a zero-sequence current transformer. Background Art

[0002] With the continuous development and improvement of modern power systems, higher requirements are placed on the safety and stability of power equipment, especially in power protection and monitoring systems. As one of the important devices, zero-sequence current transformers undertake the important task of monitoring the operating status of the system and preventing electrical accidents. Zero-sequence current transformers are widely used in many fields such as electricity, railways, petroleum, and chemical industry. Their main function is to detect the zero-sequence component in the three-phase current, especially in abnormal conditions such as ground faults, leakage, and overload. Therefore, the stability, accuracy, and durability of zero-sequence current transformers are particularly important.

[0003] The technical solution of the zero-sequence current transformer in the prior art is as follows: 1) Publication No. CN110459381B discloses a split-type current transformer, in which the technical application includes a front assembly and a rear assembly that are combined, the front assembly includes an upper base, an upper cover and a U-shaped upper iron core, the upper base and the upper cover are combined by a snap-fit ​​structure, and the upper iron core is accommodated in an upper iron core channel formed by the combination of the upper base and the upper cover; the rear assembly includes a lower base and a first bracket, a second bracket and a U-shaped lower iron core accommodated in the lower base, the first bracket and the second bracket are combined by a snap-fit ​​structure, the first bracket, the second bracket and the lower iron core are combined to form a lower iron core assembly, a coil is wound on the lower iron core assembly to form a magnetic core coil assembly, and the lower base is connected to the magnetic core coil assembly by a snap-fit ​​structure. The components of the front assembly and the rear assembly of the split-type current transformer of the present invention are all fastened by a snap-fit ​​structure, which can be quickly installed without tools, and the fastening is firm, reliable and has good sealing performance.

[0004] 2) Publication No. CN208256458U discloses a split-type zero-sequence current transformer, which includes a semi-circular first shell and a second shell and a semi-circular first iron core and a second iron core. The first iron core and the second iron core are respectively cast in the first shell and the second shell by resin, and the two ends of the first shell and the second shell are detachably connected to form an annular shell and fixed by a throat clamp. The two ends of the first iron core and the second iron core are connected to form an annular iron core, and the first iron core or the second iron core is wound with a winding coil, and the annular shell is provided with a terminal, and the winding coil is connected to the terminal. The inner circumference of the annular shell is provided with 4 cable clamps along the circumferential direction. The utility model has a simple structure and good stability, is easy to manufacture, has fewer manufacturing molds, is low in cost, is easy to install and maintain, and has a good fixing effect.

[0005] 3) Publication No. CN206806160U discloses an open-type zero-sequence current transformer, which includes a first semi-ring-shaped insulating shell and a second semi-ring-shaped insulating shell in the technical application. A first semi-ring-shaped iron core is arranged inside the first semi-ring-shaped insulating shell. A first coil is arranged outside the first semi-ring-shaped iron core, and a first outer insulating layer is arranged outside the first coil. The second semi-ring-shaped insulating shell has the same structure on one side, with a first magnetic conductive layer on the upper end face of the first semi-ring-shaped iron core and a second magnetic conductive layer on the lower end face of the first semi-ring-shaped iron core. A third magnetic conductive layer is arranged on the upper end face of the second semi-ring-shaped iron core and a fourth magnetic conductive layer is arranged on the lower end face of the second semi-ring-shaped iron core. The first semi-ring-shaped insulating shell and the second semi-ring-shaped insulating shell are buckled together to form a circular ring, and an angle iron piece is clamped on the outer surface, and the end of the angle iron piece is fixed by bolts and nuts. The utility model adopts a clamp structure, which satisfies the convenience of user loading and unloading.

[0006] 4) Publication No. CN107045929A discloses a method for manufacturing a split-type zero-sequence transformer and a casting mold. In this technical application, the process steps include manufacturing two semi-circular cores, winding coils, casting the body mold, and assembling the semi-circular body casting body. The mold body is composed of a semi-circular body, left and right templates arranged on both sides of the semi-circular body, and an upper cover plate assembly. The mold has a semi-circular cavity, and the inner surface of the cover plate is provided with two grooves. The grooves are provided with a strong magnet for adsorbing the semi-circular coil core to be cast. Its characteristics are: the manufacturing method shortens the production cycle of the product, improves the qualified rate of the product once put into production, and reduces the production cost. The mold adopts an assembled structure, with low manufacturing cost, convenient and quick assembly and disassembly, reduced labor intensity, and improved labor efficiency. The semi-circular coil core is hoisted by a strong magnet adsorption method, with large adsorption force and accurate positioning. The semi-circular coil core will not change after positioning, so that the thickness of the cast transformer insulator is the same, ensuring the insulation performance of the product and also improving the product qualification rate.

[0007] However, the above zero-sequence current transformer has some technical problems in practical use.

[0008] 1. The zero-sequence current transformers installed in the cable room of the widely used KYN series switchgear are all circular hole (arc-shaped structure) current transformers with different apertures. When using this type of transformer, the three-phase cable must be inserted into the cable room from one cable hole. This threading method is only applicable to three-core cables or single-core cables with small cross-sections. With the continuous growth of power load, these two types of cables are gradually replaced by single-core cables with large cross-sections and larger current carrying capacity. Some feeders even require two cables to be connected in parallel for each phase. Because of the torque of the cable itself, the three-phase cable cannot be inserted into the cable room from one cable hole, but needs to be inserted from three cable holes respectively. In this way, the existing zero-sequence cable transformer cannot be installed in the cable room, and the zero-sequence current transformer can only be randomly installed at a three-phase cable collection point under the cabinet. At the same time, the shielded grounding wire of the cable should be led out from the cable room to the bottom of the cabinet to pass through the zero-sequence current transformer. At the same time, the insulation protection of the grounding wire should be done well to prevent grounding when it does not pass through the transformer, affecting the zero-sequence current measurement, causing the relay protection and small current grounding line selection device to operate incorrectly. The corresponding transformer secondary cable should also be led to the zero-sequence current transformer under the cabinet. Improper construction is very likely to pose a safety hazard. In some cases, the zero-sequence current transformer cannot be installed in or under the cabinet. In this case, a phase-sequence current transformer is used to synthesize the zero-sequence current to replace the zero-sequence current transformer. However, due to the differences in the characteristics of the three-phase current transformer itself, and the small value of the zero-sequence current when the line is single-phase grounded, and the large transformation ratio of the phase current transformer, the unbalanced current of the three-phase current transformer is large, which cannot correctly reflect the zero-sequence current of the line and cannot realize the grounding line selection function.

[0009] 2. The existing exposed installation method of round hole current transformer lacks sufficient protection measures and is easily affected by external factors such as vibration, dust and moisture, which may affect its long-term operation stability.

[0010] 3. The installation process of existing round hole current transformers is cumbersome. Different models and sizes of transformers need to be equipped with different bases, and the installation of the base often requires precise hole adjustment and separate processing, resulting in low production efficiency. The assembly process also often requires steps such as punching and fixing brackets, which not only increases production costs but also prolongs assembly time. In addition, after the brackets and bases of some transformers are damaged, there is a lack of suitable replacement parts, which affects the subsequent maintenance and continued use of the equipment.

[0011] 4. Although the snap-fit ​​structure in the prior art round hole current transformer is convenient for quick installation, it may become loose or worn during long-term use, affecting the firmness of the connection, especially in a high pressure or vibration environment, which may lead to a decrease in sealing and even leakage. Summary of the invention

[0012] The purpose of the present invention is to provide a zero-sequence current transformer, which realizes efficient, stable and reliable zero-sequence current measurement and protection functions through a rectangular opening and closing design combined with an innovative modular structure and an integrated base.

[0013] To achieve the above object, the present invention provides the following technical solution: a zero-sequence current transformer, comprising a transformer module and an integrated base, wherein: The transformer module is an open-close zero-sequence current transformer, and the transformer module has a front component, a rear component and an angle iron piece that locks the front component and the rear component, wherein the front component and the rear component are both U-shaped iron core joints and are arranged in a mirror image, and movable bars are arranged on the front side of the front component and the rear component, and the angle iron pieces are distributed on the outside of the front component and the rear component and are locked by bolts, and a rectangular iron core channel is formed between the front component and the rear component; The integrated base is used to lock and install the transformer module and provide protection. The integrated base includes a base frame, a protective outer frame and a locking structure, wherein mounting edges are arranged on both sides of the bottom of the base frame, an opening is arranged on the top surface of the base frame, interconnected through holes are arranged on both sides of the top of the base frame, and adjustment long holes are arranged on the sides of the front and rear ends of the base frame.

[0014] Preferably, the transformer module is of an open-and-closed design, with a front component and a rear component, which are locked and connected by an angle iron piece. Specifically, the front component and the rear component are both U-shaped iron core junctions, which are arranged in a mirror image, which is convenient for sensing and processing current. The front sides of the upper and rear components are provided with movable bars for adjusting their gaps during installation to adapt to different types of current testing environments; the angle iron piece surrounds the outer periphery of the transformer module and is fastened by bolts to ensure the stability and accuracy of the module structure.

[0015] Preferably, the protective outer frame includes an upper frame and a lower frame which are distributed upward and downward, wherein the lower frame is in a shape that cooperates with the inner side of the opening of the bottom frame seat, and the bottom of the lower frame extends into the inner side of the bottom frame seat through the opening, and the front and rear ends of the lower frame are provided with adjustment screws that pass through the adjustment long holes and can be locked in a limited position.

[0016] Preferably, a vertical slot body and a transverse slot body are provided on the lower frame, wherein the inner side of the transverse slot body cooperates with the outer side surfaces of the front component and the rear component.

[0017] Preferably, long sliding holes are provided on both sides of the top of the lower frame, and both ends of the bottom of the upper frame extend into the inner side of the vertical slot body and are locked by bolts.

[0018] Preferably, a groove matching the top of the front component is provided at the top of the upper frame, and long sliding holes are provided at both ends of the bottom of the upper frame extending into the inner side of the long sliding hole, wherein a through hole is provided on the side of the long sliding hole close to the rear component, and the connecting ends of the angle iron pieces at both ends of the rear component extend into the through hole, and spring pins are provided in the through hole to limit the connecting ends.

[0019] Preferably, the locking structure is arranged on the bottom side of the opening of the lower frame, and the locking structure includes a mounting plate, a shell, a drive rod, a worm, a worm wheel, a screw, a guide rod, an adjusting arm and a locking block, wherein the mounting plate is fixed at the bottom of the shell, and a matching worm and worm wheel are installed on the inside of the shell, wherein one side of the worm shaft end is connected to the drive rod, and the screw is connected to the axial side of the worm wheel.

[0020] Preferably, the guide rod and the screw rod are distributed in parallel up and down, the adjustment arm is sleeved on the guide rod and the screw rod, and an arc-shaped locking block is installed on the upper end of the adjustment arm. The two locking blocks move with the driving rod and clamp the bottom side of the rear component.

[0021] Preferably, the locking structure is located at the bottom side of the lower frame opening, which can ensure the fixity and stability of the transformer module after installation. The design of the worm gear makes the adjustment more precise, and the adjustment arm and the locking block can effectively clamp the bottom side of the rear assembly under the action of the drive rod to prevent the transformer module from loosening due to external vibration or impact during operation.

[0022] Preferably, the locking structure adopts a worm gear design, which makes the adjustment more precise and can achieve effective clamping of the bottom side of the rear component. Through the cooperation of the adjustment arm and the locking pressure block, the position of the rear component can be accurately controlled to ensure the stability and firmness of the transformer module; in addition, through the action of the drive rod, the locking pressure block can clamp the rear component to ensure the stability of the transformer module after installation, avoiding loosening due to external vibration or impact during operation, thereby improving the long-term reliability of the equipment; and the locking structure is combined with the protective outer frame to provide comprehensive protection for the transformer module. The structural design is reasonable, which can effectively prevent the transformer from being impacted or disturbed by the outside world during use and ensure its normal operation.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The zero-sequence current transformer of the present invention realizes efficient, stable and reliable zero-sequence current measurement and protection functions by combining a rectangular opening and closing design with an innovative modular structure and an integrated base; in addition, the rectangular opening and closing design is adopted to solve the problem of unbalanced current in normal operation of the zero-sequence current formed by the three-phase CT, and solves the problem that the original round hole type zero-sequence current transformer cannot be installed in the case of single-core cables, large-section cables, double cables, etc., while ensuring that the accuracy and saturation multiple of the zero-sequence current transformer meet the use requirements, and is more suitable for large-section single-core cables and the parallel connection of two cables.

[0024] Quick installation and maintenance: The upper and rear components of the transformer module are locked by angle iron pieces and bolts, and the bolt fastening method is adopted to ensure the stability and accuracy of the structure. This design simplifies the installation process, saves time and cost, and improves production and maintenance efficiency.

[0025] Enhanced protection and stability: The integrated base and protective frame provide effective protection measures to avoid the influence of external factors such as vibration, dust, moisture, etc. Even in harsh environments, the transformer can operate stably and ensure long-term reliability.

[0026] Strong adaptability: Active bars are set on the front sides of the upper and rear components, which can flexibly adjust the gap according to the installation environment. This design enables the mutual inductor to be widely used in various power systems, solving the limitations of traditional mutual inductors in current detection.

[0027] Efficient locking structure: The locking structure in the integrated base adopts a worm gear design, which can accurately adjust and ensure the firm fixation of the transformer module to prevent loosening or leakage due to external vibration or impact. This design improves the safety of the equipment and reduces the possibility of failure.

[0028] Improved installation and removal convenience: The design of the protective frame combines easy-to-install long sliding holes and screws, making the assembly and removal process of the transformer module easier, reducing the requirement for precise adjustment of the base during assembly and improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 Schematic diagram of the structure of a transformer module in an embodiment of the present invention; Figure 3 A schematic diagram of the structure of an integrated base in an embodiment of the present invention; Figure 4 Schematic diagram of the locking structure in the embodiment of the present invention Figure 1 ; Figure 5 Schematic diagram of the locking structure in the embodiment of the present invention Figure 2 .

[0030] In the figure: 1. Transformer module; 101. front assembly; 102. rear assembly; 103. angle iron piece; 104. movable bar; 2. Integrated base; 201. Bottom frame seat; 202. Upper frame; 203. Lower frame; 204. Groove; 205. Mounting plate; 206. Shell; 207. Drive rod; 208. Screw; 209. Worm gear; 210. Guide rod; 211. Adjustment arm; 212. Locking block; 213. Worm. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0033] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] See also Figure 1 The present invention provides a technical solution: a zero-sequence current transformer, including a transformer module 1 and an integrated base 2.

[0035] See also Figure 1-Figure 2 In this embodiment, the transformer module 1 is a split-type zero-sequence current transformer. The transformer module 1 has a front component 101 and a rear component 102 that are combined, and an angle iron piece 103 that locks the front component 101 and the rear component 102. The front component 101 and the rear component 102 are both U-shaped iron core junctions and are mirror-imaged. A movable bar 104 is arranged on the front side of the front component 101 and the rear component 102. The angle iron pieces 103 are distributed on the outside of the front component 101 and the rear component 102 and are locked by bolts. A rectangular iron core channel is formed between the front component 101 and the rear component 102.

[0036] In this embodiment, the transformer module 1 is of an open-and-closed design, having a front component 101 and a rear component 102, which are locked and connected by an angle iron piece 103. Specifically, the front component 101 and the rear component 102 are both U-shaped iron core junctions, which are mirror-imaged, so as to facilitate the sensing and processing of current. A movable bar 104 is provided on the front side of the upper and rear components 102, which is used to adjust the gap during installation to adapt to different types of current testing environments. The angle iron piece 103 surrounds the outer periphery of the transformer module 1 and is fastened by bolts to ensure the stability and accuracy of the module structure.

[0037] See also Figure 1 , Figure 3 In this embodiment, the integrated base 2 is used to lock and install the transformer module 1 and provide protection. The integrated base 2 includes a bottom frame seat 201, a protective outer frame and a locking structure, wherein mounting edges are arranged on both sides of the bottom of the bottom frame seat 201, an opening is arranged on the top surface of the bottom frame seat 201, through holes are arranged on both sides of the top of the bottom frame seat 201, and adjustment long holes are arranged on the sides of the front and rear ends of the bottom frame seat 201; the protective outer frame includes an upper frame 202 and a lower frame 203 which are distributed in an upper and lower manner, wherein the lower frame 203 is in a shape that matches the inner side of the opening of the bottom frame seat 201, the bottom of the lower frame 203 extends into the inner side of the bottom frame seat 201 from the opening, and the front and rear ends of the lower frame 203 are arranged to pass through the adjustment long holes And it can limit and lock the adjusting screw; the lower frame 203 is provided with a vertical slot body and a horizontal slot body, wherein the inner side of the horizontal slot body cooperates with the outer side surfaces of the front component 101 and the rear component 102; long sliding holes are provided on both sides of the top of the lower frame 203, and the two ends of the bottom of the upper frame 202 extend into the inner side of the vertical slot body and are locked by bolts; the top of the upper frame 202 is provided with a groove 204 that cooperates with the top of the front component 101, and the two ends of the bottom of the upper frame 202 that extend into the inner side of the long sliding hole are provided with long sliding holes, wherein the long sliding hole is provided with a through hole on the side close to the rear component 102, and the connecting ends of the angle iron pieces 103 at both ends of the rear component 102 extend into the through hole, and the through hole is provided with a spring pin (not shown in the figure) for limiting the connecting end.

[0038] In this embodiment, the integrated base 2 is composed of a bottom frame seat 201, a protective outer frame and a locking structure, and the design makes the installation and protection of the transformer more convenient and safer. The bottom frame seat 201 is provided with mounting edges on both sides to facilitate docking with the installation interface of the device. The top surface of the bottom frame seat 201 is provided with an opening to facilitate the fitting of the transformer module 1 with the base, and the adjustable long hole and perforation design provide a flexible installation space, which can meet the installation requirements of transformers of different models and sizes.

[0039] In this embodiment, the protective outer frame of the integrated base 2 is composed of an upper part and a lower part. The upper frame 202 and the lower frame 203 are locked by sliding grooves and bolts to fix the entire transformer module 1. A groove body is provided in the lower frame 203, and a plurality of grooves are designed to match the arc shape of the outer periphery of the rear component 102 to ensure the stable embedding of the transformer module 1.

[0040] See also Figure 3-Figure 5 In this embodiment, the locking structure is arranged on the bottom side of the opening of the lower frame 203, and the locking structure includes a mounting plate 205, a shell 206, a driving rod 207, a worm 213, a worm wheel 209, a screw 208, a guide rod 210, an adjustment arm 211 and a locking pressure block 212, wherein the mounting plate 205 is fixed at the bottom of the shell 206, and a matching worm 213 and a worm wheel 209 are installed on the inner side of the shell 206, wherein one side of the axial end of the worm 213 is connected to the driving rod 207, and the axial side of the worm wheel 209 is connected to the screw 208; the guide rod 210 and the screw 208 are distributed in parallel at the upper and lower parts, and the adjustment arm 211 is mounted on the guide rod 210 and the screw 208, and an arc-shaped locking pressure block 212 is installed on the upper end of the adjustment arm 211, and the two locking pressure blocks 212 move with the driving rod 207 and clamp the bottom side of the rear component 102.

[0041] In this embodiment, the locking structure is located at the bottom side of the opening of the lower frame 203, which can ensure the fixity and stability of the transformer module 1 after installation. The design of the worm gear 209 and the worm 213 makes the adjustment more precise, and the adjustment arm 211 and the locking block 212 can effectively clamp the bottom side of the rear assembly 102 under the action of the driving rod 207 to prevent the transformer module 1 from loosening due to external vibration or impact during operation.

[0042] In this embodiment, the locking structure adopts the design of worm wheel 209 and worm 213, so that the adjustment is more precise and the bottom side of the rear component 102 can be effectively clamped. Through the cooperation of the adjustment arm 211 and the locking block 212, the position of the rear component 102 can be accurately controlled to ensure the stability and firmness of the transformer module 1; in addition, through the action of the driving rod 207, the locking block 212 can clamp the rear component 102 to ensure the stability of the transformer module 1 after installation, and avoid loosening due to external vibration or impact during operation, thereby improving the long-term reliability of the equipment; and the locking structure is combined with the protective frame to provide comprehensive protection for the transformer module 1. The reasonable structural design can effectively prevent the transformer from being impacted or disturbed by the outside world during use, and ensure its normal operation.

[0043] In this embodiment, the design of the locking structure allows for diversified installation of the transformer module 1 and the integrated base, adapts to transformers of different models and sizes, provides greater installation flexibility, and meets the requirements of different current test environments.

[0044] This embodiment also provides the installation and application steps of the zero-sequence current transformer: Preparation: Before installing the zero-sequence current transformer, first ensure that the power supply of the power equipment has been cut off to ensure the safety of the operators, check that the transformer model used matches the specifications of the power system, and ensure that the operating current range of the zero-sequence current transformer is suitable for the target system; Dismantle and prepare the transformer: Connect the upper and rear components 102 of the transformer as needed, ensuring that the base is fully connected to the transformer module 1; Adjusting the movable bar 104: According to the actual size and layout of the cables in the power system, use the adjustment screw to adjust the movable bar 104 on the front side of the transformer to ensure that the transformer module 1 can be successfully installed in the target position and adapt to the testing requirements of different cables or currents; Fix the transformer: Use bolts to firmly lock the upper and rear components 102 of the transformer. By tightening the bolts, ensure that the transformer is firmly installed and will not loosen due to cable movement or external vibration. Adjust the locking structure: Check the locking structure in the integrated base 2 to ensure that the worm gear 209 and worm 213 device has completely locked the transformer module 1, making it firm and able to remain stable in long-term use; Install the transformer: Place the transformer module 1 accurately at the appropriate position of the cable. You can choose to install the transformer at the cable gathering point or in the cable room as needed. When the cable passes through the transformer aperture, ensure that the cable is not twisted or damaged during the passage; Connect the power system: After completing the installation of the transformer, connect the transformer to the power protection and monitoring system through appropriate cables. Adjust the current signal output interface according to the required monitoring range; Start the system and test: Start the power equipment, ensure that the zero-sequence current transformer works correctly, monitor the output of the current signal, and perform relevant parameter tests to ensure that the equipment is within the normal operating range and can accurately reflect the zero-sequence current state; Maintenance and inspection: Regularly check the operation of the zero-sequence current transformer, including the buckle structure, bolt locking and the integrity of the protective frame. In harsh environments, regular cleaning and maintenance should be carried out according to actual conditions to ensure stability in long-term use.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A zero-sequence current transformer, characterized in that: It comprises a transformer module (1) and an integrated base (2), wherein: The transformer module (1) is a split-type zero-sequence current transformer, and comprises a front component (101), a rear component (102) and an angle iron piece (103) for locking the front component (101) and the rear component (102), wherein the front component (101) and the rear component (102) are both U-shaped iron core junctions and are arranged in a mirror image, a movable bar (104) is arranged on the front side of the front component (101) and the rear component (102), the angle iron piece (103) is distributed on the outside of the front component (101) and the rear component (102) and is locked by bolts, and a rectangular iron core channel is formed between the front component (101) and the rear component (102); The integrated base (2) is used to lock and install the transformer module (1) and provide protection, and the integrated base (2) comprises a base frame seat (201), a protective outer frame and a locking structure, wherein mounting edges are arranged on both sides of the bottom of the base frame seat (201), an opening is arranged on the top surface of the base frame seat (201), through holes are arranged on both sides of the top of the base frame seat (201), and adjustment slots are arranged on the sides of the front and rear ends of the base frame seat (201).

2. A zero-sequence current transformer according to claim 1, characterized in that: The protective outer frame comprises an upper frame (202) and a lower frame (203) which are arranged in an upper and lower manner, wherein the lower frame (203) is in a shape that matches the inner side of the opening of the bottom frame seat (201), the bottom of the lower frame (203) extends from the opening into the inner side of the bottom frame seat (201), and the front and rear ends of the lower frame (203) are provided with adjustment screws that pass through the adjustment long holes and can be limited and locked.

3. A zero-sequence current transformer according to claim 2, characterized in that: The lower frame (203) is provided with a vertical slot body and a horizontal slot body, wherein the inner side of the horizontal slot body cooperates with the outer side surfaces of the front component (101) and the rear component (102).

4. A zero-sequence current transformer according to claim 2, characterized in that: Long sliding holes are provided on both sides of the top of the lower frame (203), and both ends of the bottom of the upper frame (202) extend into the inner side of the vertical slot body and are locked by bolts.

5. A zero-sequence current transformer according to claim 2, characterized in that: The top of the upper frame (202) is provided with a groove (204) that matches the top of the front component (101).

6. A zero-sequence current transformer according to claim 1, characterized in that: The locking structure is arranged on the bottom side of the opening of the lower frame (203), and comprises a mounting plate (205), a housing (206), a driving rod (207), a worm (213), a worm wheel (209), a screw (208), a guide rod (210), an adjustment arm (211) and a locking pressing block (212), wherein the mounting plate (205) is fixed to the bottom of the housing (206).

7. A zero-sequence current transformer according to claim 6, characterized in that: A worm (213) and a worm wheel (209) are mounted on the inner side of the housing (206) in a matching manner, wherein one side of the shaft end of the worm (213) is connected to the driving rod (207), and the shaft center side of the worm wheel (209) is connected to the screw rod (208).

8. A zero-sequence current transformer according to claim 6, characterized in that: The guide rod (210) and the screw rod (208) are arranged in parallel at the top and bottom. The adjustment arm (211) is sleeved on the guide rod (210) and the screw rod (208). An arc-shaped locking pressure block (212) is installed on the upper end of the adjustment arm (211). The two locking pressure blocks (212) move with the driving rod (207) and clamp the bottom side of the rear component (102).

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