High-precision current transformer
By using a semi-circular group and a threaded connection method in the current transformer, the problem of loose core contact was solved, and a high-precision current transformer design was achieved.
Patent Information
- Application Number
- CN202422993697.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-11-14
- Estimated Expiration
- 2034-12-05
AI Technical Summary
The core contact of existing toroidal current transformers is not tight, resulting in low measurement accuracy.
A spring sheet is placed behind the semi-circular assembly, and the two semi-circular mutual inductance units are connected by a toothed crimping method. The elasticity of the spring sheet and the gradual tightening effect of the toothed crimping ensure that the two ends of the iron core are tightly connected.
This improved the measurement accuracy of the current transformer, ensured tight contact of the iron core, and achieved a high-precision design.
Smart Images
Figure CN223552387U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of current transformer technology, specifically to a high-precision current transformer. Background Technology
[0002] A current transformer is an instrument that measures current by converting a large primary current into a small secondary current based on the principle of electromagnetic induction. A current transformer consists of a closed iron core and windings. Its primary winding has very few turns and is connected in series with the circuit whose current needs to be measured.
[0003] Therefore, it often carries the entire current of the circuit, resulting in a relatively large number of turns in the secondary winding. Connected in series with measuring instruments and protection circuits, the secondary circuit of the current transformer is always closed during operation. Consequently, the impedance of the series coils in the measuring instruments and protection circuits is very small, and the operating state of the current transformer is close to a short circuit. The current transformer converts a large primary current into a small secondary current for measurement; the secondary side must not be open-circuited.
[0004] The current transformer includes a semi-ring current transformer unit. The outer sides of one end of two semi-ring current transformer units are hinged together by a hinge shaft. The semi-ring current transformer unit can be opened by the hinge shaft, so that the circuit to be tested can be placed between the two current transformer units through the opening. The other end is provided with a locking part, which connects the two semi-ring current transformer units to form a ring. Existing ring current transformers use a snap-locking method, which results in insufficient contact of the iron core and low measurement accuracy. Utility Model Content
[0005] The purpose of this invention is to overcome the defects in the existing technology and provide a high-precision current transformer.
[0006] To achieve the above objectives, the technical solution of this utility model is to design a high-precision current transformer, comprising two semi-ring current transformer units. Each semi-ring current transformer unit includes a semi-ring current transformer housing, which has a semi-ring mounting groove. A semi-ring winding assembly is provided within the semi-ring mounting groove. The semi-ring winding assembly consists of a semi-ring iron core and a coil wound on the semi-ring iron core. A semi-ring cover plate is provided on one side of the semi-ring current transformer housing. Iron core through holes for the iron core to pass through are provided at both ends of the semi-ring current transformer housing and the semi-ring cover plate. A spring piece is also provided within the annular mounting groove to pull the semi-ring winding assembly inwards towards the center of the ring. The two halves of the semi-ring inductor housing are pressed together. One half-ring inductor housing has a slot at each end. The other half-ring inductor housing has a slot at each end. The two halves of the semi-ring inductor housing are connected by a snap fastener. The snap fastener includes a T-shaped elongated end and an elongated snap fastener strip integrally connected to the end. The snap fastener strip has a row of snap fastener patterns on its side. The end of the snap fastener is inserted into the slot of the semi-ring inductor housing, and the snap fastener strip is inserted into the slot of the other half-ring inductor housing, so that the two halves of the semi-ring inductor housing are interlocked and gradually locked together.
[0007] A further preferred technical solution is that the slot is a T-shaped open slot, the slot is arranged along the width direction of the semi-ring mutual inductance shell, and the end of the slot near the semi-ring cover plate is also open.
[0008] A further preferred technical solution is that the slot is an open slot with a mouth shape, the slot is arranged along the width direction of the semi-annular mutual inductor housing, and the opening direction of the slot is arranged along the circumference of the semi-annular mutual inductor housing.
[0009] A further preferred technical solution is that the spring is an elastic spring, and the elastic spring is an arched elastic spring.
[0010] A further preferred technical solution is that each of the two semi-annular cover plates has a wiring hole at a pair of corresponding ends, and the two ends of a cable pass through the wiring hole and are electrically connected to the semi-circular group, so that the two semi-circular groups are connected in series. The other end of the semi-annular cover plate where the slot is located is also provided with a wiring hole, and a cable is also provided in the wiring hole to connect to an external power source.
[0011] The advantages and beneficial effects of this utility model are as follows: a spring sheet is placed behind the semi-circular group, and a toothed snap-fit method is used on both sides. The toothed snap gradually tightens, bringing the two ends of the iron core closer together. Under the action of the spring sheet, the elastic force at both ends also increases. This ensures that the two ends of the iron core in the two semi-circular groups are tightly connected when the toothed snap gradually tightens, thus ensuring the high-precision design of the current transformer. Attached Figure Description
[0012] Figure 1 This is an isometric drawing of this utility model;
[0013] Figure 2 This is a closed isometric drawing of this utility model;
[0014] Figure 3 This is an exploded isometric drawing of this utility model;
[0015] In the diagram: 10. Semi-ring mutual inductor housing; 11. Slot; 12. Card slot; 13. Opening; 14. Opening card slot; 15. Semi-ring mounting slot; 20. Threaded fastener; 21. End; 22. Threaded fastener band; 30. Semi-ring cover plate; 31. Wiring hole; 40. Semi-ring assembly; 41. Semi-ring iron core; 50. Cable; 60. Spring. Detailed Implementation
[0016] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.
[0017] like Figures 1 to 3 As shown, a high-precision current transformer includes two semi-ring current transformer units. Each semi-ring current transformer unit includes a semi-ring current transformer housing 10. The semi-ring current transformer housing 10 is provided with a semi-annular mounting groove 15. A semi-circular winding assembly 40 is provided in the semi-annular mounting groove 15. The semi-circular winding assembly 40 is composed of a semi-ring iron core 41 and a coil wound on the semi-ring iron core 41. A spring piece 60 is also provided in the annular mounting groove 15 to press the semi-circular winding assembly 40 towards the inner ring center. A semi-ring cover plate 30 is provided on one side of the semi-ring current transformer housing 10. After the semi-ring current transformer housing 10 and the semi-ring cover plate 30 are fastened together, both ends are provided with iron core through holes for the semi-ring iron core 41 to pass through.
[0018] In this embodiment, the spring 60 is an elastic spring, which is an arched elastic spring. When the two semi-ring mutual inductance units are fastened together, the semi-ring assembly 40 is compressed and deformed by mutual squeezing.
[0019] One of the semi-annular mutual inductor housings 10 has a slot 11 at each end. The slot is a T-shaped opening slot, and the slot 11 is arranged along the width direction of the semi-annular mutual inductor housing. The end of the slot 11 near the semi-annular cover plate 30 is also an opening 13. The other semi-annular mutual inductor housing 10 has a slot 12 at each end. The slot 12 is a U-shaped opening slot 14, and the slot 12 is arranged along the width direction of the semi-annular mutual inductor housing 10. The opening direction of the slot 12 is arranged along the circumference of the semi-annular mutual inductor housing 10. The two ends of the two semi-ring mutual inductance housings 10 are respectively connected by a toothed buckle 20. The toothed buckle 20 includes a T-shaped elongated end 21 and an elongated toothed buckle band 22 integrally connected to the end. A row of teeth is provided on one side of the toothed buckle band 22. The end 21 of the toothed buckle 20 is inserted into the slot 11 of the semi-ring mutual inductance housing 10, and then the toothed buckle band 22 of the toothed buckle 20 is inserted into the slot 12 of the other semi-ring mutual inductance housing 10, so that the two semi-ring mutual inductance housings 10 are interlocked and gradually locked together.
[0020] Each pair of corresponding ends of the two semi-annular cover plates 30 is provided with a wiring hole 31. The two ends of a cable 50 pass through the wiring hole 31 and are electrically connected to the semi-encircling group 40, so that the two semi-encircling groups 40 are connected. The other end of the semi-annular cover plate 30 where the slot 12 is located is also provided with a wiring hole 31. A cable 50 is also provided in the wiring hole 31 for external power supply.
[0021] One of the semi-ring mutual inductance housings 10 and 30 has a flange at the edge of the core through hole at both ends, and the other semi-ring mutual inductance housing 10 and 30 has a concave flange at the edge of the core through hole at both ends. When the two semi-ring mutual inductance units are connected, their flanges are adapted to the concave flanges.
[0022] The flange and the concave edge are arranged in a quadrilateral shape, preferably, the flange and the concave edge are arranged in a square shape.
[0023] In this embodiment, a spring sheet is placed behind the semi-circular group 40, and the two sides are connected by a snap fastener 20. As the snap fastener 20 gradually tightens, the two ends of the semi-circular iron core 41 are brought closer together. Under the action of the spring sheet 60, the elastic force at both ends also increases. This ensures that the two ends of the semi-circular iron core 41 in the two semi-circular groups 40 are tightly connected when the snap fastener 20 gradually tightens, thus ensuring the high-precision design of the current transformer.
[0024] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.
Claims
1. A high-precision current transformer, comprising two semi-ring current transformer units, each semi-ring current transformer unit comprising a semi-ring current transformer housing, the semi-ring current transformer housing having a semi-ring mounting groove, a semi-ring assembly being provided within the semi-ring mounting groove, the semi-ring assembly being composed of a semi-ring iron core and a coil wound on the semi-ring iron core, a semi-ring cover plate being provided on one side of the semi-ring current transformer housing, and iron core through holes for the iron core to pass through being provided at both ends of the semi-ring current transformer housing and the semi-ring cover plate, characterized in that: The annular mounting groove is also equipped with a spring piece to press the semi-circular assembly towards the inner center of the ring; each end of one semi-circular mutual inductor housing is provided with a slot; each end of the other semi-circular mutual inductor housing is provided with a locking groove; the two ends of the two semi-circular mutual inductor housings are connected by a threaded buckle, the threaded buckle includes a T-shaped elongated end and an elongated threaded buckle band integrally connected to the end; the side of the threaded buckle band is provided with a row of threaded buckle patterns; the end of the threaded buckle is inserted into the slot of the semi-circular mutual inductor housing, and the threaded buckle band is inserted into the locking groove of the other semi-circular mutual inductor housing, so that the two semi-circular mutual inductor housings are interlocked and gradually locked together.
2. A high-precision current transformer according to claim 1, characterized in that: The slot is a T-shaped open slot, which is arranged along the width direction of the semi-ring mutual inductance housing, and the end of the slot near the semi-ring cover plate is also open.
3. A high-precision current transformer according to claim 1, characterized in that: The slot is an open slot shaped like a mouth, and the slot is set along the width direction of the semi-annular mutual inductor housing. The opening direction of the slot is set along the circumference of the semi-annular mutual inductor housing.
4. A high-precision current transformer according to claim 3, characterized in that: The spring is an elastic spring, and the elastic spring is an arched elastic spring.
5. A high-precision current transformer according to claim 4, characterized in that: Each of the two semi-annular cover plates has a wiring hole at a pair of corresponding ends. The two ends of a cable pass through the wiring hole and are electrically connected to the semi-circular group, so that the two semi-circular groups are connected in series. The other end of the semi-annular cover plate where the slot is located is also provided with a wiring hole, and a cable is also provided in the wiring hole to connect to an external power source.