Low-voltage current transformer for state grid metering

Abstract

The application relates to the technical field of current transformers, in particular to a low-voltage current transformer for state grid metering, which comprises a transformer body, a fixed plate one and a fixed plate two arranged at the top and the bottom of the transformer body respectively, two fixed bolts arranged at the two ends of the fixed plate one and the fixed plate two respectively, an adjusting ring rotatably arranged at the top of a ring-shaped seat, three locking mechanisms evenly arranged in the adjusting ring, an unlocking mechanism arranged in the top end of the adjusting ring, and a first fixing mechanism and a second fixing mechanism arranged in the inside of the fixed plate one and the inside of a secondary plate respectively. The transformer body has the functions of fixing single cable and three pipelines, avoids the problems of magnetic field distortion caused by position deviation of single cable or three pipelines during work, ensures the accuracy of the transformer body in inductive current metering, and guarantees the safety of power distribution.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of current transformers, in particular to a low-voltage current transformer for state grid metering. BACKGROUND

[0002] A low-voltage current transformer is a special transformer used in a low-voltage power distribution system, and its core function is to reduce the larger primary side current in the circuit to a smaller secondary side current at a fixed ratio, so as to ensure the safe operation of subsequent metering and protection equipment. State grid metering equipment needs to be used in cooperation with a suitable low-voltage current transformer, which reduces the large current in the low-voltage circuit at a fixed ratio to ensure accurate collection of power consumption data by the state grid.

[0003] The middle window hole of the current transformer is usually passed through by a single current-carrying cable. When it is necessary to monitor the insulation state of the cable, a balance loop formed by the cable, its shielding layer grounding pipe and an empty pipe is used to capture the tiny leakage current. At this time, there are three wires passing through the inside of the current transformer. The existing current transformer does not have the function of fixing the pipeline in the middle. The position offset of the wire will cause distortion of the magnetic field, resulting in additional errors of the current transformer, which seriously affects the accuracy of the metering. When the unsecured wire shakes due to vibration, external force or thermal expansion and contraction, if its insulation layer is damaged, it is easy to collide and discharge with the transformer or surrounding parts, and even cause a short circuit, which brings potential safety hazards to power distribution. SUMMARY

[0004] The purpose of the present application is to provide a low-voltage current transformer for state grid metering to solve the problems raised in the background.

[0005] To achieve the above purpose, the present application provides the following technical scheme: a low-voltage current transformer for state grid metering, comprising a transformer body, a fixed plate one and a fixed plate two are arranged at the top and the bottom of the transformer body respectively, two fixed bolts are arranged at both ends of the fixed plate one and the fixed plate two respectively, an annular seat is fixedly installed at the top of the fixed plate one, an adjusting ring is rotatably installed at the top of the annular seat, a secondary plate is arranged at the top of the adjusting ring, three wire-through grooves are arranged in the inside of the secondary plate, three locking mechanisms are arranged in the inside of the adjusting ring, an unlocking mechanism is arranged in the inside of the top end of the adjusting ring, and a first fixing mechanism and a second fixing mechanism are arranged in the inside of the fixed plate one and the secondary plate respectively.

[0006] Preferably, connecting pieces are fixedly installed at both sides of the transformer body, and limit plates are symmetrically fixedly installed at one end of the fixed plate one and the fixed plate two close to the two connecting pieces.

[0007] Preferably, the first fixing mechanism comprises a bidirectional screw rod and a guide rod one, one end of the bidirectional screw rod is rotatably installed in the inside of the fixed plate one, the guide rod one is fixedly installed in the inside of the fixed plate one away from the bidirectional screw rod, the outside of both ends of the bidirectional screw rod is threadedly connected with a clamping plate one, the end away from the bidirectional screw rod of the clamping plate one is slidably sleeved with the outside of the guide rod one.

[0008] Preferably, the inside of the annular seat is provided with an annular limiting sliding groove, the bottom of the adjusting ring is fixedly installed with an annular limiting sliding strip, and the adjusting ring is slidably installed on the top of the annular seat through the cooperation of the annular limiting sliding strip and the annular limiting sliding groove.

[0009] Preferably, the locking mechanism comprises an L-shaped plug-in plate, a plug-in groove, a first locking assembly and a second locking assembly, one end of the L-shaped plug-in plate is fixedly installed at the bottom of the auxiliary plate, the plug-in grooves are uniformly formed on the top of the adjusting ring, the plug-in grooves are matched with the L-shaped plug-in plate, the first locking assembly comprises two slide rods, the slide rods are fixedly installed in the inside of the adjusting ring, the outside of the slide rods is commonly slidably sleeved with a locking block, the outside of the slide rods is sleeved with a spring one, the bottom of the L-shaped plug-in plate is provided with a locking groove one, the locking groove one is matched with the locking block, and the top of the locking block is fixedly installed with a protrusion.

[0010] Preferably, the second locking assembly comprises a transmission block, the transmission block is slidably installed in the inside of the adjusting ring, a plurality of uniformly distributed locking strips are fixedly installed on the side away from the plug-in groove of the transmission block, two spring twos are symmetrically fixedly installed on one side of the transmission block, the sides away from the transmission block of the spring twos are fixedly connected with the adjusting ring, a plurality of uniformly distributed locking grooves two are formed in the inside of the annular seat, the locking grooves two are matched with the locking strips, grooves are formed at both ends of the transmission block, protrusions are arranged in the inside of the grooves, and the sides away from the transmission block of the protrusions are fixedly connected with the inner wall of the adjusting ring.

[0011] Preferably, the unlocking mechanism comprises an unlocking ring, the unlocking ring is rotatably installed on the top of the adjusting ring, three uniformly distributed adjusting grooves are formed in the inside of the adjusting ring, unlocking rods are movably installed in the inside of the adjusting grooves, three uniformly distributed strip-shaped grooves are formed in the inside of the top of the adjusting ring, the strip-shaped grooves are arranged below the unlocking ring, the bottom ends of the unlocking rods are movably arranged in the inside of the three strip-shaped grooves, the bottoms of the unlocking rods are matched with the three protrusions, a plurality of uniformly distributed spring threes are fixedly installed between the end of the unlocking ring and the inner wall of the adjusting ring, three uniformly distributed driving blocks are fixedly installed on the top of the unlocking ring, three uniformly distributed arc-shaped grooves are formed on the top of the adjusting ring, and the driving blocks are arranged in the inside of the arc-shaped grooves.

[0012] Preferably, the second fixing mechanism includes a threaded rod and a guide rod 2. The threaded rod is rotatably installed inside the sub-plate, and the guide rod 2 is fixedly installed inside the sub-plate. A clamping plate 2 is threadedly connected to the outside of the threaded rod, and the end of the clamping plate 2 away from the threaded rod is slidably sleeved on the outside of the guide rod 2.

[0013] Compared with the prior art, the beneficial effects of the present invention are:

[0014] 1. The first fixing mechanism can fix a single cable in the middle of the transformer body. When three pipelines pass through the middle of the transformer body, the auxiliary plate is fixed on the top of the adjusting ring, and then the second fixing mechanism is used to fix the three pipelines respectively. The present invention enables the transformer body to fix a single cable and three pipelines through the first and second fixing mechanisms, avoiding problems such as magnetic field distortion caused by positional deviation of a single cable or three pipelines during operation, ensuring the accuracy of the transformer body in measuring induced current and providing a guarantee for power distribution safety.

[0015] 2. With the locking mechanism and rotatable adjusting ring, before installing the sub-plate, the position of the sub-plate and adjusting ring can be adjusted accordingly based on the actual position of the three pipelines in the cable accessories. Then, the locking mechanism can be used to quickly fix the position of the adjusting ring and the ring seat, and the sub-plate and the adjusting ring, thereby improving the applicability of the second fixing mechanism. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0017] Figure 2 This is a schematic diagram of the transformer body structure of the present invention;

[0018] Figure 3 This is a partial three-dimensional structural diagram of the present invention;

[0019] Figure 4 This is a schematic diagram of the internal structure of the fixing plate of the present invention;

[0020] Figure 5 This is a schematic diagram of the annular seat structure of the present invention;

[0021] Figure 6 This is a schematic diagram of the bottom structure of the adjusting ring of the present invention;

[0022] Figure 7 This is a partial cross-sectional view of the adjusting ring of the present invention;

[0023] Figure 8 This is a schematic diagram of a portion of the internal structure of the adjusting ring of the present invention;

[0024] Figure 9 This is a schematic diagram of the locking and unlocking mechanisms of the present invention;

[0025] Figure 10 This is a schematic diagram of the locking mechanism structure of the present invention;

[0026] Figure 11 This is a schematic diagram of the internal structure of the top of the adjusting ring of the present invention;

[0027] Figure 12 This is a schematic diagram of the subplate structure of the present invention;

[0028] Figure 13 This is a schematic diagram of the internal structure of the sub-plate of the present invention.

[0029] The components represented by each number in the attached diagram are listed below: 1. Current transformer body; 2. Fixing plate one; 3. Fixing plate two; 4. Fixing bolt; 5. Connecting piece; 6. Limiting plate; 7. Bidirectional lead screw; 8. Guide rod one; 9. Clamping plate one; 10. Annular seat; 11. Adjusting ring; 12. Sub-plate; 13. Wire groove; 14. Annular limiting slide groove; 15. Annular limiting slide bar; 16. L-shaped plug-in plate; 17. Plug-in slot; 18. 19. Slide rod; 20. Locking block; 21. Spring 1; 22. Locking groove 1; 23. Protrusion; 24. Transmission block; 25. Locking bar; 26. Spring 2; 27. Locking groove 2; 28. Groove; 29. ​​Protrusion; 30. Unlocking ring; 31. Adjustment groove; 32. Unlocking rod; 33. Strip groove; 34. Spring 3; 35. Toggle block; 36. Arc groove; 37. Threaded rod; 38. Guide rod 2; 39. Clamping plate 2. Detailed Implementation

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

[0031] This invention provides a technical solution: such as Figure 1 - Figure 13The present invention relates to a low-voltage current transformer for metering by the State Grid, comprising a transformer body 1, a fixing plate 2 and a fixing plate 3 respectively provided at the top and bottom of the transformer body 1, two fixing bolts 4 respectively provided at both ends of the fixing plate 2 and the fixing plate 3, an annular seat 10 fixedly installed at the top of the fixing plate 2, an adjusting ring 11 rotatably installed at the top of the annular seat 10, a sub-plate 12 provided at the top of the adjusting ring 11, three evenly distributed wire grooves 13 opened inside the sub-plate 12, three evenly distributed locking mechanisms provided inside the adjusting ring 11, an unlocking mechanism provided inside the top of the adjusting ring 11, and a first fixing mechanism and a second fixing mechanism respectively provided inside the fixing plate 2 and the sub-plate 12.

[0032] Connectors 5 are fixedly installed on both sides of the transformer body 1. Limiting plates 6 are symmetrically fixedly installed on the ends of the fixing plate 1 and fixing plate 2 and fixing plate 3 near the two connectors 5.

[0033] The first fixing mechanism includes a bidirectional lead screw 7 and a guide rod 8. The bidirectional lead screw 7 is rotatably installed at one end inside the fixing plate 2, and the guide rod 8 is fixedly installed at the end of the fixing plate 2 away from the bidirectional lead screw 7. Both ends of the bidirectional lead screw 7 are threadedly connected to clamping plates 9. The ends of the two clamping plates 9 away from the bidirectional lead screw 7 are slidably sleeved on the outside of the guide rod 8.

[0034] The annular seat 10 has an annular limiting groove 14 inside, and an annular limiting slide bar 15 is fixedly installed at the bottom of the adjusting ring 11. The adjusting ring 11 is slidably installed on the top of the annular seat 10 through the mutual cooperation of the annular limiting slide bar 15 and the annular limiting groove 14.

[0035] The locking mechanism includes an L-shaped plug plate 16, a plug groove 17, a first locking component, and a second locking component. The L-shaped plug plate 16 is fixedly installed at one end of the bottom of the sub-plate 12. The plug grooves 17 are evenly opened on the top of the adjusting ring 11. The plug grooves 17 and the L-shaped plug plate 16 cooperate with each other. The first locking component includes two slide rods 18. Both slide rods 18 are fixedly installed inside the adjusting ring 11. The locking blocks 19 are slidably sleeved on the outside of the two slide rods 18. Springs 20 are sleeved on the outside of both slide rods 18. A locking groove 21 is opened at the bottom of the L-shaped plug plate 16. The locking groove 21 cooperates with the locking block 19. A protrusion 22 is fixedly installed on the top of the locking block 19.

[0036] The second locking assembly includes a transmission block 23, which is slidably installed inside the adjusting ring 11. Multiple evenly distributed locking bars 24 are fixedly installed on the side of the transmission block 23 away from the insertion slot 17. Two springs 25 are symmetrically fixedly installed on one side of the transmission block 23. The side of each spring 25 away from the transmission block 23 is fixedly connected to the adjusting ring 11. Multiple evenly distributed locking slots 26 are opened inside the annular seat 10. The multiple locking slots 26 cooperate with the multiple locking bars 24. Grooves 27 are opened at both ends of the transmission block 23. Protrusions 28 are provided inside the two grooves 27. The side of each protrusion 28 away from the transmission block 23 is fixedly connected to the inner wall of the adjusting ring 11.

[0037] The unlocking mechanism includes an unlocking ring 29, which is rotatably mounted on the top of an adjusting ring 11. The adjusting ring 11 has three evenly distributed adjusting grooves 30 inside, and unlocking rods 31 are movably mounted inside each of the three adjusting grooves 30. The top of the adjusting ring 11 has three evenly distributed strip grooves 32, all located below the unlocking ring 29. The bottom ends of the three unlocking rods 31 are movably mounted inside the three strip grooves 32, and the bottoms of the three unlocking rods 31 respectively cooperate with three protrusions 22. Multiple evenly distributed springs 33 are fixedly installed between the end of the unlocking ring 29 and the inner wall of the adjusting ring 11. Three evenly distributed actuating blocks 34 are fixedly installed on the top of the unlocking ring 29. The top of the adjusting ring 11 has three evenly distributed arc-shaped grooves 35, and the three actuating blocks 34 are respectively located inside the three arc-shaped grooves 35.

[0038] The second fixing mechanism includes a threaded rod 36 and a guide rod 37. The threaded rod 36 is rotatably installed inside the sub-plate 12, and the guide rod 37 is fixedly installed inside the sub-plate 12. A clamping plate 38 is threadedly connected to the outside of the threaded rod 36, and the end of the clamping plate 38 away from the threaded rod 36 is slidably sleeved on the outside of the guide rod 37.

[0039] Working principle: When in use, with the four limiting plates 6, and the four fixing bolts 4, the fixing plate 1 2 and the fixing plate 2 3 are respectively fixed to the top and bottom of the transformer body 1. When only a single cable passes through the middle of the transformer body 1, you only need to rotate the bidirectional screw 7 directly. At the same time, under the action of the guide rod 1 8, the two clamping plates 1 9 move closer to each other, which can fix the single cable.

[0040] When the cable, its shielding grounding pipe, and an empty pipe pass through the middle of the transformer body 1, after all three pipes have passed through the middle of the transformer body 1, adjust the position of the adjusting ring 11 and the sub-plate 12 according to the position of the three pipes, and then install the sub-plate 12 on top of the adjusting ring 11 so that the three pipes are respectively located inside the three wire slots 13. When installing the sub-plate 12, first insert the three L-shaped plug plates 16 at the bottom of the sub-plate 12 into the three plug slots 17 respectively. The movement process of a set of corresponding first locking components and second locking components is as follows: When one of the L-shaped plug plates 16 is inserted into the corresponding plug slot 17, the locking block 19 moves away from the L-shaped plug plate 16 along the two slide rods 18, and the two springs 20 are compressed. When the L-shaped plug plate 16 descends to the bottom, the locking slot 21 corresponds to the locking block 19, and the locking block 19 is compressed by the two springs 20. Under the action of 20, it moves towards the locking groove 21 and enters the interior of the locking groove 21, thereby fixing the L-shaped plug plate 16. At the same time, the bottom end of the L-shaped plug plate 16 exerts a force on the transmission block 23, and the transmission block 23 moves away from the L-shaped plug plate 16. The transmission block 23 moves a certain distance under the action of the two grooves 27 and the two protrusions 28 to prevent the transmission block 23 from disengaging from the adjusting ring 11. As the transmission block 23 moves, the two springs 25 are compressed, and the multiple locking bars 24 are inserted into the corresponding locking grooves 26, thereby fixing the adjusting ring 11. The movement process of the other two first locking components and the second locking components is the same as described above. After the sub-plate 12 is fixed, the three threaded rods 36 are rotated respectively. At the same time, under the action of the three guide rods 37, the corresponding clamping plates 38 move accordingly, thereby fixing the three pipelines.

[0041] By using the first fixing mechanism, a single cable can be fixed in the center of the transformer body 1. When three pipelines pass through the center of the transformer body 1, the auxiliary plate 12 is fixed on the top of the adjusting ring 11, and then the three pipelines are fixed separately by the second fixing mechanism. The present invention enables the transformer body 1 to fix a single cable and three pipelines by using the first and second fixing mechanisms, avoiding problems such as magnetic field distortion caused by positional deviation of a single cable or three pipelines during operation, ensuring the accuracy of the transformer body 1 in measuring induced current and providing a guarantee for power distribution safety.

[0042] When the sub-plate 12 needs to be removed, any one of the toggle blocks 34 can be moved to rotate the unlocking ring 29. With the cooperation of the three adjustment slots 30 and the three strip slots 32, the three unlocking rods 31 slide away from the sub-plate 12 at the same time. The three unlocking rods 31 push the protrusions 22 on the top of the three locking blocks 19 at the same time, so that the three locking blocks 19 move away from their respective L-shaped plug plates 16. The three locking blocks 19 disengage from their respective three locking slots 1 21 and are no longer fixed to the three L-shaped plug plates 16, so that the sub-plate 12 can be removed. After the three L-shaped plug plates 16 disengage from the three plug slots 17, the three transmission blocks 23 are also reset under the action of their respective springs 25. The multiple locking bars 24 on one side of the three transmission blocks 23 disengage from their respective locking slots 26, so that the adjustment ring 11 and the ring seat 10 are unlocked. The corresponding adjustment can be made according to the position of the three pipelines in the next adjustment.

[0043] With the locking mechanism and the rotatable adjusting ring 11, the position of the sub-plate 12 and the adjusting ring 11 can be adjusted by rotating the angle according to the actual position of the three pipelines before the sub-plate 12 is installed. Then, the locking mechanism can be used to quickly fix the position of the adjusting ring 11 and the ring seat 10, and the sub-plate 12 and the adjusting ring 11, thereby improving the applicability of the second fixing mechanism.

[0044] 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.

[0045] Although embodiments of the 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 invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A low-voltage current transformer for State Grid metering, comprising a transformer body (1), characterized in that: The top and bottom of the transformer body (1) are respectively provided with a fixing plate 1 (2) and a fixing plate 2 (3). Two fixing bolts (4) are respectively provided at both ends of the fixing plate 1 (2) and the fixing plate 2 (3). An annular seat (10) is fixedly installed on the top of the fixing plate 1 (2). An adjusting ring (11) is rotatably installed on the top of the annular seat (10). A sub-plate (12) is provided on the top of the adjusting ring (11). Three evenly distributed wire grooves (13) are opened inside the sub-plate (12). Three evenly distributed locking mechanisms are provided inside the adjusting ring (11). An unlocking mechanism is provided inside the top of the adjusting ring (11). A first fixing mechanism and a second fixing mechanism are respectively provided inside the fixing plate 1 (2) and the sub-plate (12). The locking mechanism includes an L-shaped plug plate (16), a plug groove (17), a first locking component, and a second locking component. The L-shaped plug plate (16) is fixedly installed at one end of the bottom of the sub-plate (12). The plug groove (17) is evenly opened on the top of the adjusting ring (11). The plug groove (17) and the L-shaped plug plate (16) cooperate with each other. The first locking component includes two slide rods (18). Both slide rods (18) are fixedly installed inside the adjusting ring (11). The two slide rods (18) are slidably fitted with a locking block (19) on their outer sides. Both slide rods (18) are fitted with a spring (20). The bottom of the L-shaped plug plate (16) is provided with a locking groove (21). The locking groove (21) cooperates with the locking block (19). The top of the locking block (19) is fixedly installed with a protrusion (22). The second locking component includes a transmission block (23), which is slidably installed inside the adjusting ring (11). Multiple evenly distributed locking bars (24) are fixedly installed on the side of the transmission block (23) away from the insertion slot (17). Two springs (25) are symmetrically fixedly installed on one side of the transmission block (23). The side of the two springs (25) away from the transmission block (23) is fixedly connected to the adjusting ring (11). Multiple evenly distributed locking slots (26) are opened inside the annular seat (10). The multiple locking slots (26) cooperate with the multiple locking bars (24). Grooves (27) are opened at both ends of the transmission block (23). Protrusions (28) are provided inside the two grooves (27). The side of the two protrusions (28) away from the transmission block (23) is fixedly connected to the inner wall of the adjusting ring (11). The unlocking mechanism includes an unlocking ring (29), which is rotatably mounted on the top of an adjusting ring (11). The adjusting ring (11) has three evenly distributed adjusting grooves (30) inside, and an unlocking rod (31) is movably mounted inside each of the three adjusting grooves (30). The top of the adjusting ring (11) has three evenly distributed strip grooves (32) inside, all located below the unlocking ring (29). The bottom ends of the three unlocking rods (31) are movably mounted on the three... Inside the groove (32), the bottom of the three unlocking rods (31) respectively cooperates with the three protrusions (22). Multiple evenly distributed springs (33) are fixedly installed between the end of the unlocking ring (29) and the inner wall of the adjusting ring (11). Three evenly distributed actuating blocks (34) are fixedly installed on the top of the unlocking ring (29). Three evenly distributed arc grooves (35) are opened on the top of the adjusting ring (11). The three actuating blocks (34) are respectively set inside the three arc grooves (35).

2. The low-voltage current transformer for State Grid metering as described in claim 1, characterized in that: Connectors (5) are fixedly installed on both sides of the transformer body (1), and limit plates (6) are symmetrically fixedly installed on one end of the first fixing plate (2) and the second fixing plate (3) near the two connectors (5).

3. A low-voltage current transformer for State Grid metering according to claim 1, characterized in that: The first fixing mechanism includes a bidirectional lead screw (7) and a guide rod (8). The bidirectional lead screw (7) is rotatably installed at one end inside the fixing plate (2). The guide rod (8) is fixedly installed at the end inside the fixing plate (2) away from the bidirectional lead screw (7). Both ends of the bidirectional lead screw (7) are threadedly connected to clamping plates (9). The ends of the two clamping plates (9) away from the bidirectional lead screw (7) are slidably sleeved on the outside of the guide rod (8).

4. A low-voltage current transformer for State Grid metering as described in claim 1, characterized in that: The annular seat (10) has an annular limiting groove (14) inside, and the bottom of the adjusting ring (11) is fixedly installed with an annular limiting slide bar (15). The adjusting ring (11) is slidably installed on the top of the annular seat (10) through the mutual cooperation of the annular limiting slide bar (15) and the annular limiting groove (14).

5. A low-voltage current transformer for State Grid metering according to claim 1, characterized in that: The second fixing mechanism includes a threaded rod (36) and a guide rod (37). The threaded rod (36) is rotatably installed inside the sub-plate (12), and the guide rod (37) is fixedly installed inside the sub-plate (12). The threaded rod (36) is threadedly connected to a clamping plate (38), and the end of the clamping plate (38) away from the threaded rod (36) is slidably sleeved on the outside of the guide rod (37).

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