Low-partial-discharge combined mutual inductor
Through the modular design and screw adjustment structure of low local release combined transformers, the winding integration problem in the existing technology is solved, the production efficiency and insulation performance are improved, and the local release is reduced, and the efficient and stable operation of the combined transformer is achieved.
Patent Information
- Application Number
- CN202422024646.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-20
- Publication Date
- 2025-08-05
- Estimated Expiration
- 2034-08-20
AI Technical Summary
The iron core, primary voltage winding, secondary voltage winding, primary current winding and secondary current winding of existing combined transformers cannot be integrated and modular, resulting in low production efficiency and poor insulation performance, uneven casting of epoxy resin is easy to crack, and locally high.
The modular design of low-local combo transformer includes a modular coil assembly and screw adjustment structure to ensure the insulation spacing between the windings and the uniformity of the thickness of the epoxy resin layer. The winding is fixed by lifting and support, and the use of cable ties and screw adjustments to achieve efficient assembly and insulation performance improvement.
The combined transformer has a simple structure, stable and reliable performance, high production efficiency, good insulation performance and local lowering effect.
Smart Images
Figure CN223193620U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of mutual inductors, in particular to a low partial discharge combined mutual inductor. Background Art
[0002] A combination instrument transformer (CT) is a device designed for three-phase power systems, combining a three-phase voltage transformer and three single-phase (or two single-phase) current transformers. It is primarily used for three-phase energy metering and measurement in power systems. The design and use of CTs are intended to meet the power system's requirements for high accuracy and reliability while ensuring personal and equipment safety. The combination transformer includes an epoxy resin cast body, an iron core, a primary voltage winding, a secondary voltage winding, a primary current winding, and a secondary current winding. The iron core, primary voltage winding, secondary voltage winding, primary current winding, and secondary current winding of the existing combination transformer cannot be integrated and modularized, which makes the mold assembly of the combination transformer more complicated, greatly affecting production efficiency, and cannot guarantee the insulation distance between the primary voltage winding and the secondary voltage winding, and between the primary current winding and the secondary current winding. When epoxy resin casting is used, it is easy to cause uneven thickness of the epoxy resin layer, and bubbles are easily generated between the epoxy resin casting layers, causing the epoxy resin layer to crack easily. As a result, the combination transformer has defects such as poor insulation performance, unstable performance, and high partial discharge. Summary of the Invention
[0003] The purpose of the utility model is to overcome the defects of the prior art and provide a low partial discharge combined mutual inductor with simple structure, stable and reliable performance, high production efficiency and good insulation performance.
[0004] To achieve the above-mentioned purpose, the utility model adopts a low partial discharge combined mutual inductor, comprising an epoxy resin casting body, a plurality of terminal blocks arranged on the epoxy resin casting body, and a coil assembly arranged in the epoxy resin casting body, wherein the coil assembly comprises two symmetrically arranged voltage cores, two voltage secondary windings respectively wound on the two voltage cores, a hanging plate arranged on one side of the two voltage secondary windings, two voltage primary windings respectively sleeved on the two voltage secondary windings, two supporting members respectively arranged on the two voltage secondary windings and connected to the two voltage primary windings, two current cores, a winding Two current primary windings are on two current cores and connected to multiple terminal blocks, two current secondary windings are respectively sleeved on the two current primary sets, and a current support frame is arranged on the other side of the two voltage secondary windings. One end of the current support frame is provided with a fixing plate connected to the two voltage secondary windings, two adjusting screws are symmetrically arranged on the fixing plate, and a support plate connected to the two current secondary windings is provided on the two adjusting screws. One end of the adjusting screw is inserted into the through hole of the support plate, and an adjusting nut is respectively provided on the two sides of the corresponding support plate.
[0005] The beneficial effects of the above structure are as follows: the coil assembly adopts a modular structure design, and the iron core, voltage primary winding, voltage secondary winding, current primary winding, and current secondary winding are integrated and modularized through hanging parts, supports, and current support frames, thereby realizing modular assembly of the coil assembly and the casting mold, and improving the mold installation efficiency. The two hanging parts can be fixed on the bottom plate of the casting mold, thereby facilitating the hanging of the coil assembly and the bottom plate. The two supports can ensure the insulation distance between the voltage secondary winding and the voltage primary winding, and the current support frame can ensure the insulation distance between the current primary winding and the current secondary winding. When epoxy resin casting is used, the epoxy resin casting thickness between the voltage primary winding and the voltage secondary winding, and between the current primary winding and the current secondary winding can be ensured. The thickness of the epoxy resin layer is uniform, bubbles are not easily generated between the epoxy resin casting layers, and the epoxy resin layer will not crack, and the insulation performance is better. The current support frame utilizes a screw-type adjustment mechanism. Rotating the adjustment screw allows the support plate height to be adjusted, facilitating the adjustment of the insulation distance between the primary and secondary windings. This ensures a consistent insulation distance between the primary and secondary windings. This combined transformer offers advantages such as a simple structure, stable and reliable performance, high production efficiency, excellent insulation performance, and low partial discharge.
[0006] In particular, two fixing plates are provided at both ends of the support plate, corresponding to the two secondary windings. Each fixing plate has an arcuate groove that fits the two secondary windings. The fixing plates of the support plate fit onto the secondary windings via the arcuate grooves, increasing the contact area between the fixing plates and the secondary windings, ensuring a more compact connection between the fixing plates and the secondary windings.
[0007] Specifically, each of the two support members has a support arm at one end that mates with the two primary voltage windings. The support arm has a groove that fits against the outer wall of the primary voltage winding, and the primary voltage winding is secured to the support arm via a strap. The support arms of the support members fit against the primary voltage winding via the grooves, increasing the contact area between the support arms and the primary voltage winding, ensuring a more compact connection between the support arms and the primary voltage winding.
[0008] In particular, the two voltage secondary windings are connected to the hoisting plate, the two voltage secondary windings to the current support frame, and the two voltage secondary windings to the two supports, respectively, via cable ties. This securement facilitates assembly of the two voltage secondary windings to the hoisting plate, the two voltage secondary windings to the current support frame, and the two voltage secondary windings to the two supports, thereby improving assembly efficiency of the combined transformer.
[0009] In particular, the hanging plate is symmetrically provided with two hanging holes, through which the hanging plate can be fixed to the bottom plate of the casting mold, thereby facilitating the assembly of the hanging plate and the casting mold and improving the assembly efficiency of the coil assembly and the casting mold. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 It is a front view of the internal structure of an embodiment of the present utility model.
[0011] Figure 2 It is a left view of the internal structure of an embodiment of the present utility model.
[0012] Figure 3 It is a top view of the internal structure of an embodiment of the present utility model. DETAILED DESCRIPTION
[0013] like Figures 1 to 3As shown, the embodiment of the utility model is a low partial discharge combined mutual inductor, including an epoxy resin casting body 10, a plurality of terminal blocks 11 arranged on the epoxy resin casting body 10, and a coil assembly 20 arranged in the epoxy resin casting body 10, wherein the coil assembly 20 includes two symmetrically arranged voltage cores 21, two voltage secondary windings 22 respectively wound on the two voltage cores 21, a hanging plate 23 arranged on one side of the two voltage secondary windings 22, two voltage primary windings 24 respectively sleeved on the two voltage secondary windings 22, two supporting members 25 respectively arranged on the two voltage secondary windings 22 and connected to the two voltage primary windings 24, two current cores 26, and a coil assembly 26 wound on the two current cores 26. The two primary current windings 27 connected to the multiple terminal blocks 11, the two secondary current windings 28 respectively mounted on the two primary current sets 27, and the current support frame 29 disposed on the other side of the two voltage secondary windings 22. A fixing plate 291 connected to the two voltage secondary windings 22 is disposed at one end of the current support frame 29. Two adjustment screws 292 are symmetrically disposed on the fixing plate 291. A support plate 293 connected to the two secondary current windings 28 is disposed on the two adjustment screws 292. One end of the adjustment screw 292 is inserted into a through hole in the support plate 293. An adjustment nut 294 is disposed on each side of the adjustment screw 292 corresponding to the support plate 293. Two fixing plates 295 are disposed at both ends of the support plate 293 corresponding to the two secondary current windings 28. Each fixing plate 295 has an arcuate groove 2951 that fits the two secondary current windings 28. The fixing plate of the support plate is attached to the current secondary winding through an arc groove, which can increase the contact area between the fixing plate and the current secondary winding, and ensure that the connection between the fixing plate and the current secondary winding is more compact. The two support members 25 are respectively provided with support arms 251 that match the two voltage primary windings 24 on one end. The support arms 251 have grooves 252 that fit on the outer peripheral wall of the voltage primary winding 24, and the voltage primary winding 24 is fixed to the support arms 251 by straps 30. The support arms of the support members are attached to the voltage primary winding through grooves, which can increase the contact area between the support arms and the voltage primary winding, and ensure that the connection between the support arms and the voltage primary winding is more compact. The two voltage secondary windings 22 and the hanging plate 23, the two voltage secondary windings 22 and the current support frame 29, and the two voltage secondary windings 22 and the two support members 25 are respectively connected by straps 31. The use of a cable tie to fix the two voltage secondary windings to the lifting plate, the two voltage secondary windings to the current support frame, and the two voltage secondary windings to the two supports facilitates the assembly of the combined transformer. The lifting plate 23 is symmetrically provided with two lifting holes 231.The hanging plate can be fixed on the bottom plate of the casting mold through the hanging holes, thereby facilitating the assembly of the hanging plate and the casting mold, and being beneficial to improving the assembly efficiency of the coil assembly and the casting mold.
[0014] The coil assembly adopts a modular design. The iron core, primary voltage winding, secondary voltage winding, primary current winding, and secondary current winding are integrated and modularized through lifting parts, supports, and a current support frame. This allows for modular assembly of the coil assembly and the casting mold, improving mold assembly efficiency. The two lifting parts can be fixed to the base plate of the casting mold, facilitating the lifting of the coil assembly to the base plate. The two supports ensure the insulation distance between the secondary voltage winding and the primary voltage winding, while the current support frame ensures the insulation distance between the primary current winding and the secondary current winding. When epoxy resin casting is used, the epoxy resin casting thickness between the primary voltage winding and the secondary voltage winding, and between the primary current winding and the secondary current winding, is guaranteed. The epoxy resin layer thickness is uniform, and bubbles are not easily generated between the epoxy resin casting layers, which will not cause the epoxy resin layer to crack, thereby improving insulation performance. The current support frame utilizes a screw-type adjustment mechanism. Rotating the adjustment screw allows the support plate height to be adjusted, facilitating the adjustment of the insulation distance between the primary and secondary windings. This ensures a consistent insulation distance between the primary and secondary windings. This combined transformer offers advantages such as a simple structure, stable and reliable performance, high production efficiency, excellent insulation performance, and low partial discharge.
Claims
1. A low partial discharge combined mutual inductor, characterized by: The invention comprises an epoxy resin casting body, a plurality of terminal blocks arranged on the epoxy resin casting body, and a coil assembly arranged in the epoxy resin casting body. The coil assembly comprises two symmetrically arranged voltage cores, two voltage secondary windings respectively wound on the two voltage cores, a hanging plate arranged on one side of the two voltage secondary windings, two voltage primary windings respectively sleeved on the two voltage secondary windings, two supporting members respectively arranged on the two voltage secondary windings and connected to the two voltage primary windings, two current cores, two current primary windings wound on the two current cores and connected to the plurality of terminal blocks, two current secondary windings respectively sleeved on the two current primary sets, and a current support frame arranged on the other side of the two voltage secondary windings. A fixing plate connected to the two voltage secondary windings is provided at one end of the current support frame, two adjusting screws are symmetrically arranged on the fixing plate, a supporting plate connected to the two current secondary windings is provided on the two adjusting screws, one end of the adjusting screw is inserted into the through hole of the supporting plate, and an adjusting nut is respectively provided on the adjusting screw at both sides of the corresponding supporting plate.
2. The low partial discharge combined mutual inductor according to claim 1, characterized in that: Two fixing plates are provided at both ends of the support plate corresponding to the two secondary current windings, and the two fixing plates are respectively provided with arc grooves that fit the two secondary current windings.
3. The low partial discharge combined mutual inductor according to claim 1 or 2, characterized in that: One end of the two support members is respectively provided with a support arm that matches the two primary voltage windings. The support arm has a groove that fits on the outer peripheral wall of the primary voltage winding, and the primary voltage winding is fixed on the support arm by a strap.
4. The low partial discharge combined mutual inductor according to claim 1 or 2, characterized in that: The two voltage secondary windings and the hoisting plate, the two voltage secondary windings and the current support frame, and the two voltage secondary windings and the two supporting members are connected respectively by cable ties.
5. The low partial discharge combined mutual inductor according to claim 1 or 2, characterized in that: Two lifting holes are symmetrically arranged on the lifting plate.