Discharge coil for epoxy resin cast insulation high voltage shunt capacitor
Patent Information
- Application Number
- CN202522053151.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-24
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-09-24
AI Technical Summary
油绝缘方式是将放电线圈置于油箱内，相对体积较大，重量较重，需要较大的安装空间
[0008]与现有技术相比，本发明的有益效果如下：本实用新型的绝缘采用环氧树脂浇注的方式绝缘，在满足放电线圈电气性能的同时，减小了产品体积，降低了成本，外形美观，安装更加方便和灵活。相对绝缘油，环氧树脂不易燃烧和爆炸，提高了放电线圈在电力系统运行的安全性和可靠性。环氧树脂绝缘将放电线圈的铁芯及一、二绕组完全密封于环氧树脂内，既满足了绝缘要求又密封防潮，基本上可以做到免维护，降低了运维的劳动强度。
Smart Images
Figure CN224841447U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of high-voltage power equipment technology, specifically to a discharge coil for a high-voltage parallel capacitor with epoxy resin casting insulation. Background Technology
[0002] A discharge coil for a high-voltage parallel capacitor is a power device that reduces the voltage at the capacitor terminals to below 50V within 5 seconds after the capacitor is disconnected from the power source. Currently, most discharge coils for high-voltage parallel capacitors use transformer oil insulation. Oil insulation places the discharge coil inside an oil tank, resulting in a relatively large volume and weight, requiring significant installation space. Furthermore, insulating oil is flammable and explosive, posing a significant safety hazard in the event of a discharge coil failure. Insulating oil is also susceptible to moisture, affecting its insulation performance and requiring regular maintenance. Summary of the Invention
[0003] To address the aforementioned shortcomings, this invention employs a mature epoxy resin vacuum casting process to encapsulate the discharge coil within epoxy resin. This not only meets the performance requirements of discharge coils for high-voltage parallel capacitors but also achieves the advantages of small size, maintenance-free operation, and reliable performance.
[0004] To achieve the above objectives, the present invention adopts the following technical solution: a discharge coil for a high-voltage parallel capacitor with epoxy resin casting insulation, comprising an iron core, a primary winding, a secondary winding, an epoxy resin shell, and a mounting base plate, characterized in that: the discharge coil is formed by epoxy resin vacuum casting to form an integral insulation structure; the iron core is a cold-rolled silicon steel sheet rolled into a rectangle with a C-shaped cross-section and an air gap at the cut, the inductance of the primary winding being adjusted by adjusting the size of the air gap; the primary winding adopts a fully insulated structure, with both terminals located above the coil and having the same level of insulation to ground; the weight of the primary winding is designed according to the discharge temperature rise requirements to ensure that the temperature rise does not exceed the standard during discharge.
[0005] Preferably, the air gap is formed by adding an insulating film at that location, and the thickness of the film is adjustable to change the size of the air gap.
[0006] Preferably, a gap is left between the primary winding and the secondary winding, which is filled with epoxy resin as interlayer insulation.
[0007] Preferably, the discharge coil can reduce the voltage at the terminals of the parallel capacitor to below 50V within 5 seconds.
[0008] Compared with existing technologies, the beneficial effects of this invention are as follows: The insulation of this invention uses epoxy resin casting, which, while meeting the electrical performance requirements of the discharge coil, reduces product size, lowers costs, improves appearance, and makes installation more convenient and flexible. Compared to insulating oil, epoxy resin is less flammable and less prone to explosion, improving the safety and reliability of the discharge coil in power system operation. The epoxy resin insulation completely seals the iron core and the first and second windings of the discharge coil within the epoxy resin, satisfying both insulation requirements and moisture protection, essentially achieving maintenance-free operation and reducing the labor intensity of maintenance. Attached Figure Description
[0009] Figure 1 This is a schematic diagram of the epoxy resin casting discharge coil structure of this utility model.
[0010] The markings in the diagram are: 1-iron core, 2-primary winding, 3-secondary winding, 4-epoxy resin shell, 5-mounting base plate, 6-air gap. Detailed Implementation
[0011] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0012] like Figure 1 As shown, this utility model discloses a discharge coil for a high-voltage parallel capacitor with epoxy resin casting insulation, comprising an iron core 1, a primary winding 2, a secondary winding 3, an epoxy resin shell 4, and a mounting base plate 5. The iron core 1 is made of cold-rolled silicon steel sheet rolled into a rectangle and cut into a C-shape. During the binding process of the iron core 1, an insulating film is added at the cut to form an air gap 6. The secondary winding 3 is wound on one long side core of the iron core 1, and then the primary winding 2 is wound around the secondary winding 3. Sufficient gaps must be left between the secondary winding 3 and the primary winding 2 to fill with epoxy resin as insulation between them. The primary winding 2 must adopt a fully insulated structure, meaning that both terminals A and X of the primary winding 2 are above the discharge coil, and both terminals have the same insulation level to ground. The minimum weight of the primary winding of the discharge coil is set according to the voltage level and discharge capacity of the parallel capacitor to ensure that the heat generated during the discharge process does not cause the temperature rise of the discharge coil to exceed the limit. The size of the air gap 6 needs to be adjusted to adjust the inductance of the primary winding 2, and in conjunction with the DC resistance of the primary winding 2, to ensure that the voltage of the parallel capacitor drops below 50V within 5 seconds during the discharge. After the discharge coil body is manufactured, it is placed in a mold and vacuum-cast with epoxy resin to form the inner and outer insulation of the discharge coil.
[0013] This invention utilizes epoxy resin casting for insulation, which, while meeting the electrical performance requirements of the discharge coil, reduces product size, lowers costs, improves appearance, and makes installation more convenient and flexible. Compared to insulating oil, epoxy resin is less flammable and less prone to explosion, enhancing the safety and reliability of the discharge coil in power system operation. The epoxy resin insulation completely seals the discharge coil core and the first and second windings within the epoxy resin, satisfying both insulation requirements and moisture protection, essentially eliminating maintenance and reducing the labor intensity of operation and maintenance.
[0014] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A discharge coil for a high-voltage parallel capacitor with epoxy resin casting insulation, comprising an iron core (1), a primary winding (2), a secondary winding (3), an epoxy resin shell (4), and a mounting base plate (5), characterized in that: The discharge coil is formed by vacuum casting of epoxy resin to form an integral insulation structure; the iron core (1) is a rectangular cold-rolled silicon steel sheet rolled into a C-shaped cross section, with an air gap (6) at the cut. The inductance of the primary winding (2) is adjusted by adjusting the size of the air gap (6); the primary winding (2) adopts a fully insulated structure, with both terminals located above the coil and having the same level of insulation to ground; the weight of the primary winding (2) is designed according to the discharge temperature rise requirements to ensure that the temperature rise does not exceed the standard during the discharge process.
2. The discharge coil for a high-voltage parallel capacitor with epoxy resin casting insulation according to claim 1, characterized in that: The air gap (6) is formed by adding an insulating film at that location, and the thickness of the film can be adjusted to change the size of the air gap.
3. The discharge coil for a high-voltage parallel capacitor with epoxy resin casting insulation according to claim 1, characterized in that: A gap is left between the primary winding (2) and the secondary winding (3), which is filled with epoxy resin as interlayer insulation.
4. The discharge coil for a high-voltage parallel capacitor with epoxy resin casting insulation according to claim 1, characterized in that: The discharge coil can reduce the voltage at the terminals of the parallel capacitor to below 50V within 5 seconds.