High-performance high-temperature-resistant dry-type air-core reactor
By using H-class epoxy resin impregnated with alkali-free untwisted glass fiber and heat-resistant insulating support strips in dry-type air-core reactors, combined with polyimide film and special coatings, the problem of structural instability of traditional reactors under high-temperature environments is solved, achieving H-class heat-resistant insulation performance and stable operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XIAN ZHONGYANG ELECTRIC CO LTD
- Filing Date
- 2025-03-24
- Publication Date
- 2026-05-26
AI Technical Summary
Traditional dry-type air-core reactors suffer from mismatched inter-turn and overall insulation performance under high temperature and complex operating conditions, leading to structural instability and affecting service life.
An alkali-free, untwisted glass fiber impregnated with H-grade epoxy resin forms a heat-resistant insulation layer. The aluminum stranded wire is then wrapped with heat-resistant insulating strips and polyimide film, combined with a special coating, to construct an all-around H-grade heat-resistant insulation structure.
It achieves Class H standard for both inter-turn and overall insulation, improves the stability and reliability of the reactor in high-temperature environments, extends its service life, and enhances heat dissipation and mechanical structure stability.
Smart Images
Figure CN224287956U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of reactor technology, specifically relating to a high-performance, high-temperature resistant dry-type air-core reactor. Background Technology
[0002] In high-temperature environments such as arid and hot substations in desert regions and power plants severely affected by solar thermal radiation, the heat resistance limitations of traditional dry-type air-core reactors become increasingly apparent. Although some products have achieved H-class inter-turn insulation, the overall insulation is only F-class. Under the combined adverse effects of continuous high temperatures, strong thermal radiation, and frequent and drastic fluctuations in power load, the aging rate of insulation materials accelerates exponentially, directly causing a sharp deterioration in the reactor's insulation performance. This, in turn, frequently triggers electrical faults such as partial discharge and inter-turn short circuits, which seriously threaten the stability and safe operation of the power system.
[0003] In existing technologies, some reactors use polyimide film to wrap the conductors to improve the inter-turn heat resistance rating. However, the traditional F-grade epoxy resin impregnated glass fiber used to encapsulate the inner and outer insulation layers makes it difficult for the overall insulation performance to match the inter-turn insulation. This significant difference in heat resistance rating between different parts can lead to uneven thermal and electrical stresses inside the reactor under high temperature and complex operating conditions, thereby compromising the overall structural stability, deteriorating weak insulation points, and affecting service life. Summary of the Invention
[0004] In order to overcome the above technical problems, the purpose of this utility model is to provide a high-performance high-temperature resistant dry-type air-core reactor. This reactor achieves an all-round H-class heat resistance level from inter-turn insulation to overall insulation, which significantly improves the long-term operational stability and reliability of the reactor under high temperature and complex working conditions.
[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0006] A high-performance, high-temperature resistant dry-type air-core reactor includes an enclosure 2 composed of aluminum stranded wires 10 of the reactor. The enclosure 2 is wound in a multi-layer cylindrical shape, and the aluminum stranded wires 10 of each layer are connected in parallel to form an electrical connection structure.
[0007] The top of the package 2 is provided with an upper star-shaped frame 4, and the bottom is provided with a lower star-shaped frame 6;
[0008] The upper star-shaped frame 4, the lower star-shaped frame 6, and the encapsulation 2 are vertically bound together using wet binding tape 3;
[0009] The aluminum stranded wire 10 is tightly wrapped with a polyimide film 11 to form an H-grade flat transposed aluminum stranded wire.
[0010] The encapsulation 2 includes an inner insulation layer 7, aluminum stranded wire 10, and an outer insulation layer 9. The impregnated glass fiber standard tape is wound in a spiral winding manner to form the inner insulation layer 7. The aluminum stranded wire 10 is tightly and orderly wound on the surface of the inner insulation layer 7. The impregnated glass fiber standard tape is wound in a spiral winding manner on the outside of the aluminum stranded wire 10 to form the outer insulation layer 9.
[0011] Several heat-resistant insulating support strips 1 are installed at 9 locations on the outer insulation layer of the encapsulation 2.
[0012] The impregnated glass fiber standard tape is wound in a spiral manner to form an inner insulation layer 7. Aluminum stranded wire 10 is tightly and orderly wound on the surface of the inner insulation layer 7. The impregnated glass fiber standard tape is wound in a spiral manner on the outside of the aluminum stranded wire 10 to form an outer insulation layer 9.
[0013] Heat-resistant insulating support strip 1 is available in 3 specifications:
[0014] It is a long rectangular strip in the longitudinal direction, and its cross-section is rectangular.
[0015] It is rectangular in shape longitudinally, with a T-shaped cross-section;
[0016] Based on a longitudinal rectangular strip, two sides are processed into curved surfaces, and its cross-section has a hyperboloid shape.
[0017] All heat-resistant insulating support bars 1 have been grooved longitudinally.
[0018] The spacing between the heat-resistant insulating support strips 1 is 90cm, and they are evenly distributed.
[0019] The outermost encapsulation 2 has a coating 5 on its outer surface;
[0020] The outer side of the coating 5 is an RTV anti-flashover coating.
[0021] The beneficial effects of this utility model are:
[0022] The transposed aluminum strands of this reactor are tightly wrapped with a polyimide film, forming an H-class flat transposed aluminum strand, which provides a solid insulation foundation for the stable operation of the reactor in high-temperature environments.
[0023] A high-temperature resistant insulating layer is formed by impregnating alkali-free, untwisted glass fibers with H-grade high-temperature resistant epoxy resin. This H-grade high-temperature resistant epoxy resin has low viscosity and can fully wet the alkali-free glass fibers.
[0024] This reactor successfully meets Class H standards for both inter-turn and overall performance. From critical insulation performance to high-temperature resistance, all indicators fully comply with Class H requirements. Under high-temperature and complex operating conditions, this reactor can operate stably for extended periods, significantly improving its applicability and reliability in various power environments. It provides a reliable guarantee for the safe and stable operation of power systems, possessing extremely high application value and market prospects.
[0025] The heat-resistant insulating support strip is longitudinally rectangular, with a rectangular or T-shaped cross-section. When the cross-section is rectangular, the four sides are regular and straight, allowing the support strip to distribute the force evenly within the reactor, providing stable and reliable support for the enclosure. The T-shaped cross-section further enhances the connection strength between the two through its unique structure.
[0026] The heat-resistant insulating support bar has a hyperboloidal cross-section. Viewed longitudinally, both sides of this support bar exhibit a curved shape. This special curved design offers significant advantages. Firstly, it optimizes the airflow channels within the reactor, allowing for smoother airflow and more efficient removal of heat generated during reactor operation, thus improving heat dissipation. Secondly, the hyperboloid structure reduces the reactor's weight. Furthermore, the hyperboloid structure disperses external pressure to some extent, enhancing the support bar's compressive strength and contributing to the overall stability of the reactor structure. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of a heat-resistant insulating support bar structure.
[0028] Figure 2 This is a schematic diagram of the reactor structure of this utility model.
[0029] Figure 3 This is a magnified view of a single-layer encapsulation. Detailed Implementation
[0030] The present invention will now be described in further detail with reference to the accompanying drawings.
[0031] like Figure 1-3 As shown, a high-performance, high-temperature resistant dry-type air-core reactor is produced by selecting alkali-free, untwisted glass fibers that meet the requirements and impregnating them with H-grade epoxy resin 8. This ensures that the glass fibers are fully and uniformly impregnated, thereby producing standard glass fiber tapes and binding tapes.
[0032] Single-encapsulation 2-winding and insulation construction:
[0033] Inner insulation layer 7 winding: The impregnated glass fiber standard tape is wound in a spiral winding manner to form the inner insulation layer 7; Conductor winding: The transposed aluminum stranded wire 10 is tightly and orderly wound on the surface of the inner insulation layer 7; Outer insulation layer 9 winding: After the transposed aluminum stranded wire 10 is wound, the impregnated glass fiber is taken again and wound onto the wound transposed aluminum stranded wire 10 to form the outer insulation layer 9.
[0034] The placement of support bar 1 and the formation of multiple envelopes 2:
[0035] After forming the single encapsulation 2, heat-resistant insulating support strips 1 are installed at the outer insulation layer 9 of the encapsulation 2. The distribution of the support strips 1 conforms to mechanical principles, and the spacing between the support strips 1 is strictly controlled. The air channels formed by these support strips 1 play an important role. When the reactor is running, the conductor generates heat when energized. The air channels can guide airflow, efficiently remove heat, reduce the operating temperature of the reactor, prevent performance degradation due to overheating, and ensure the long-term stable and efficient operation of the reactor.
[0036] Following the single-encapsulation winding steps described above, the inner insulation layer 7, the conductor, and the outer insulation layer 9 of the next encapsulation 2 are wound step by step. After each encapsulation 2 is completed, a high-temperature resistant support bar 1 needs to be installed. This process is repeated, and the support bars 1 are properly installed to form a multi-layer encapsulation 2 structure.
[0037] The multi-layer encapsulation 2 structure is coaxially mounted with the star frame. During the winding process, wet binding tape made of glass fiber impregnated with H-grade epoxy resin 8 is used to vertically bind the upper star frame 4, lower star frame 6 and encapsulation 2, so that the upper star frame 4, lower star frame 6 and encapsulation 2 form a stable whole.
[0038] The wound and bound reactors are transferred to a high-temperature curing device. Curing is then performed according to a pre-planned multi-stage curing temperature profile. This curing process offers significant advantages; through multi-stage temperature control, the H-grade epoxy resin can be fully cross-linked and cured, resulting in a more stable reactor structure and significantly improved mechanical strength and electrical performance. During curing, high-precision temperature sensors monitor temperature changes within the device in real time, ensuring a stable and accurate curing process and preventing temperature deviations from affecting curing quality.
[0039] Coating 5 Protection: After curing, using professional high-pressure spray gun equipment and following the specified spraying process parameters, the aliphatic acrylic polyurethane topcoat coating 5 is evenly sprayed onto the innermost and outermost encapsulation layer 2 of the coil. Strict control of spraying pressure, distance, and speed ensures uniform coating thickness. This coating 5 possesses excellent protective performance, effectively isolating external interference and blocking impurities such as dust, moisture, and corrosive gases. Furthermore, due to its special chemical structure and composition, it effectively resists ultraviolet radiation. Reactors exposed to outdoor environments for extended periods are highly susceptible to continuous ultraviolet radiation. This coating 5 absorbs and reflects ultraviolet rays, preventing damage such as aging and degradation of the reactor's internal structure and materials, thereby extending the reactor's service life and ensuring long-term stability of its electrical performance.
[0040] After the aliphatic acrylic polyurethane topcoat coating 5 has dried, the RTV anti-flashover coating is then sprayed on. The standard spraying process is followed to ensure uniform coverage of the anti-flashover coating. This coating 5 further enhances the reactor's protective performance in complex environments, especially under harsh conditions such as humidity and pollution, effectively preventing surface flashover and improving the reactor's operational reliability.
[0041] like Figure 1 As shown, heat-resistant insulating support strips 1 are installed at 9 locations on the outer insulation layer of the enclosure 2. These heat-resistant insulating support strips 1 have different morphological characteristics. Some heat-resistant insulating support strips 1 are rectangular strips in the longitudinal direction, with a rectangular or T-shaped cross-section. When the cross-section is rectangular, the four sides are regular and straight, allowing the support strip to distribute the force evenly within the reactor, providing stable and reliable support for the enclosure 2. The T-shaped cross-section further enhances the connection stability between the two, better resisting the effects of thermal stress and mechanical vibration during reactor operation. Other heat-resistant insulating support strips 1 have a hyperboloidal cross-section. Viewed longitudinally, the two surfaces of these support strips exhibit a curved shape. This special curved surface design has significant advantages. On the one hand, it optimizes the airflow channels inside the reactor, allowing for smoother airflow and more efficient removal of heat generated during reactor operation, thus improving heat dissipation. On the other hand, the hyperboloid structure disperses external pressure to some extent, enhancing the compressive strength of the support bars and helping to maintain the overall structural stability of the reactor. All support bars 1 are longitudinally grooved. This grooved design increases the contact points and contact area between the support bars and the enclosure 2, allowing the impregnated glass fiber to penetrate the grooves more fully during production. This results in a better bond between the support bars and the enclosure 2, forming a robust whole and effectively improving the overall structural stability. Regardless of their shape, the heat-resistant insulating support bars 1 play a crucial role in the reactor's structure, jointly ensuring its stable operation.
[0042] The spacing between the heat-resistant insulating support strips 1 is 90cm. In the multi-layer encapsulation structure of the reactor, the heat-resistant insulating support strips 1 are distributed at a spacing of 90cm, which can form a relatively uniform and stable support force at the outer insulation layer 9 of the encapsulation. This uniform support force constrains the outer periphery of the encapsulation, effectively preventing deformation of the encapsulation due to uneven stress during winding, curing, and operation, thereby ensuring that each encapsulation can maintain a good cylindrical shape and improving the regularity and stability of the overall reactor structure. The uniform spacing, while forming a cylindrical encapsulation, can also optimize the air passage structure between the encapsulations. The regular cylindrical encapsulation is conducive to the formation of stable natural convection of air in the air passage, ensuring that heat can be dissipated evenly, improving heat dissipation efficiency, ensuring the temperature stability of the reactor during operation, and further improving its electrical performance and service life.
[0043] The working principle of this utility model:
[0044] Electromagnetic working principle:
[0045] When alternating current flows through the coil of a reactor, an alternating magnetic field is generated inside the coil based on the principle of electromagnetic induction. The continuous alternation of the current causes the magnetic field to change constantly, thus inducing a self-induced electromotive force in the coil, forming inductive reactance. Inductive reactance plays a crucial role in power systems, effectively limiting the rate of change of current. When faced with voltage fluctuations, harmonic interference, or short-circuit current surges, inductive reactance can impede rapid changes in current, stabilize voltage, suppress harmonics, limit the amplitude of short-circuit current, and ensure the safe operation of the power system.
[0046] Heat dissipation working principle:
[0047] Between the coil layers of the reactor, heat-resistant insulating support bars 1 separate air channels. During the winding of each coil layer, the support bars 1 are precisely positioned according to design standards, forming a scientifically designed air channel structure. When the reactor is running, the coils generate heat due to the current flowing through them, causing the surrounding air to expand and create natural convection within the air channels. Thanks to the special design of the support bars 1 and the rational layout of the air channels, air can circulate more smoothly within the channels, quickly carrying away the heat generated by the coils, effectively reducing the coil operating temperature, and thus extending the reactor's service life.
[0048] Working principle of mechanical stability:
[0049] The vertical binding components 3 and the heat-resistant insulating support 1 provide stable support and connection for the reactor coil and star-shaped frame. In high-temperature environments, these components effectively resist thermal stress and vibration. The heat-resistant insulating support 1, with its excellent mechanical strength at high temperatures, provides reliable support for the coil, preventing deformation due to thermal stress. The vertical binding 3 maintains good toughness and fastening force at high temperatures, ensuring a tight connection between the enclosure 2 and the star-shaped frame. The overall structure maintains mechanical stability in high-temperature and vibration environments, ensuring the normal operation of the reactor.
[0050] Insulation working principle:
[0051] The transposed conductor wrapped with polyimide film 11, the insulating layer formed by winding glass fiber impregnated with H-grade high-temperature resistant epoxy resin, and the protective coating 5 together construct a reliable insulation protection system for the reactor. In high-temperature environments, the polyimide film 11 effectively isolates current due to its excellent thermal stability and good insulation properties. The H-grade epoxy resin 8 fully impregnates the alkali-free glass fiber, forming a stable insulating structure that further prevents current leakage.
[0052] As a high-performance organic polymer material, polyimide film 11 possesses a unique imide ring structure in its main chain, which endows the material with extremely excellent thermal stability. This film can withstand temperatures well above 180°C, with a typical long-term operating temperature range of 200-260°C. Within this high-temperature range, it not only maintains good chemical stability, preventing decomposition and melting, but also, due to its low shrinkage, remains tightly bonded to the aluminum stranded wire 10, effectively maintaining excellent insulation performance.
[0053] The protective coating 5 plays an indispensable role in the insulation system. On the innermost and outermost encapsulation surfaces of the reactor coil, coating 5 is precisely sprayed using a professional spray gun to form a dense protective layer, effectively preventing external impurities such as ultraviolet rays, dust, moisture, and corrosive gases from directly contacting the coil. In high-humidity environments, ordinary insulating materials are prone to insulation performance degradation due to moisture absorption; however, coating 5, with its excellent waterproof and hydrophobic properties, prevents moisture penetration, ensuring that insulation performance remains unaffected. From the perspective of enhancing insulation characteristics, coating 5 itself possesses excellent insulation performance, and it works synergistically with the internal insulation structure to further improve the overall insulation effect. When the reactor is operating, local electric field concentration may occur under voltage; coating 5 can uniformly distribute the electric field, reducing the risk of partial discharge and thus significantly enhancing insulation characteristics. Furthermore, coating 5 has high dielectric strength, enabling it to withstand higher voltages without breakdown, providing strong protection for the stable operation of the reactor in high-voltage environments. In addition, coating 5 also has good wear resistance. During the installation, commissioning, and daily maintenance of the reactor, the surface of the coil casing 2 will inevitably be subjected to external forces such as collisions and friction. The wear-resistant properties of the coating 5 can effectively reduce surface wear, maintain the integrity of the protective layer, and continuously play its role in protection and enhanced insulation. This comprehensively ensures the stable electrical performance of the reactor in harsh environments such as high temperature and high humidity, and prevents faults caused by insulation failure.
Claims
1. A high-performance, high-temperature resistant dry-type air-core reactor, characterized in that, The encapsulation (2) consists of aluminum stranded wires (10) of the reactor. The encapsulation (2) is wound in a multi-layer cylindrical shape. The aluminum stranded wires (10) of each layer are connected in parallel to form an electrical connection structure. The encapsulation (2) has an upper star-shaped frame (4) at the top and a lower star-shaped frame (6) at the bottom. The upper star-shaped frame (4), the lower star-shaped frame (6), and the encapsulation (2) are vertically tied together with wet binding tape (3); The aluminum stranded wire (10) is tightly wrapped with a polyimide film (11) to form an H-grade flat transposed aluminum stranded wire.
2. The high-performance high-temperature resistant dry-type air-core reactor according to claim 1, characterized in that, The encapsulation (2) includes an inner insulation layer (7), an aluminum stranded wire (10), and an outer insulation layer (9).
3. A high-performance, high-temperature resistant dry-type air-core reactor according to claim 1, characterized in that, Heat-resistant insulating support strips (1) are placed at the outer insulation layer (9) of the encapsulation (2).
4. A high-performance, high-temperature resistant dry-type air-core reactor according to claim 3, characterized in that, Heat-resistant insulating support strips (1) are available in 3 specifications: The first type of heat-resistant insulating support strip (1) is a rectangular strip in the longitudinal direction, and its cross-section is rectangular. The second type of heat-resistant insulating support strip (1) is a rectangular strip in the longitudinal direction, and its cross-section is T-shaped; The third type of heat-resistant insulating support strip (1) has a hyperboloid cross-section. From the longitudinal perspective, the two sides of the heat-resistant insulating support strip (1) exhibit a curved shape. All heat-resistant insulating support bars (1) have been slotted in the longitudinal direction.
5. A high-performance, high-temperature resistant dry-type air-core reactor according to claim 3, characterized in that, The spacing between the heat-resistant insulating support strips (1) is 90cm, and they are evenly distributed.
6. A high-performance, high-temperature resistant dry-type air-core reactor according to claim 1, characterized in that, The outermost encapsulation (2) has a coating (5) on its outer surface.
7. A high-performance, high-temperature resistant dry-type air-core reactor according to claim 6, characterized in that, The outer side of the coating (5) is an RTV anti-flashover coating.