A novel low-loss, lightweight ultra-high voltage reactor

Abstract

A novel low-loss, lightweight ultra-high voltage reactor, relating to the technical field of reactor equipment, includes two sets of star-shaped frames spaced apart vertically. A winding body is positioned between the two sets of star-shaped frames. Each winding body comprises multiple cylindrical encapsulations with vertically penetrating openings, arranged coaxially and nested radially. Each encapsulation has an annular inner cavity, within which an electromagnetic coil is wound. The electromagnetic coil comprises multiple electromagnetic wires, each consisting of multiple stranded conductors, all covered with an insulation layer. This design reduces eddy current losses generated by the magnetic field, balances coil temperature rise, and, combined with the circumferential support of the electromagnetic coil's outer encapsulation, utilizes a differentiated thickness inner and outer encapsulation structure design. This design reduces the thickness of the outer encapsulation while maintaining the inner layer's insulation strength, thereby reducing insulation material consumption and overall equipment weight.

Description

Technical Field

[0001] This invention relates to the field of reactor equipment technology, specifically to a new type of low-loss, lightweight ultra-high voltage reactor. Background Technology

[0002] Existing traditional dry-type air-core reactors generally adopt conventional transposed electromagnetic wires combined with a general epoxy resin integral encapsulation structure. With the continuous increase in the single-unit capacity of ultra-high voltage projects, the defects in equipment operation have become increasingly prominent. Conventional conductors are significantly affected by the skin effect and proximity effect, resulting in high eddy current losses. Under high-frequency operating conditions, the AC resistance of the reactor increases significantly, and the coil generates a lot of heat. At the same time, in order to balance the current of each winding and meet the insulation sealing strength requirements, the existing reactor coil conductors have a large amount of redundancy. The inner and outer encapsulations adopt the same thickness insulation design, resulting in high consumption of insulation materials and winding consumables. Existing technology lacks an integrated design concept for coordinated optimization, and cannot simultaneously take into account multiple indicators such as low eddy current losses, lightweight, and balanced temperature rise. It has a series of technical shortcomings such as high energy consumption, large weight, and poor heat dissipation. Summary of the Invention

[0003] To address the problems of high eddy current losses due to the skin effect and excessive material consumption in existing ultra-high voltage reactors, this invention provides a novel low-loss, lightweight ultra-high voltage reactor.

[0004] The technical solution of this invention is as follows: A novel low-loss, lightweight ultra-high voltage reactor includes two sets of star-shaped frames arranged at vertical intervals. A winding body is provided between the two sets of star-shaped frames. The winding body includes multiple cylindrical encapsulation bodies with through openings at the top and bottom. The multiple encapsulation bodies are coaxial and nested at intervals along the radial direction. Each of the encapsulation bodies is provided with an annular inner cavity, and an electromagnetic coil is wound inside the annular inner cavity. The electromagnetic coil includes multiple electromagnetic wires, and each electromagnetic wire includes multiple stranded conductors, and the conductors are covered with an insulating layer.

[0005] In order to effectively reduce the winding gap, lower the overall AC resistance of the coil, weaken the loss problems caused by the skin effect and proximity effect, and at the same time improve the overall structural compactness and heat dissipation uniformity of the coil, and reduce the heat loss of the coil, each of the electromagnetic wires is arranged to abut against the adjacent electromagnetic wires, and multiple electromagnetic wires are twisted and pressed into a rectangular cross-section.

[0006] In order to ensure the stability of the conductor stranding structure and effectively reduce eddy current losses, while avoiding excessive winding material consumption and increased equipment weight due to an excessive number of electromagnetic wires, and to achieve both low loss and lightweight performance, the electromagnetic wires are provided in 8-12 strands.

[0007] In order to achieve uniform current distribution, significantly reduce eddy current loss and heat generation under high frequency conditions, avoid the defects of concentrated current and high loss in single-layer stranding, and reduce AC resistance, the multiple conductors are arranged in a double layer, with at least one central conductor in the inner layer and the outer layer evenly distributed around the central conductor.

[0008] In order to form a stable and symmetrical double-layer twisted structure, achieve uniform distribution of conductor force and current carrying capacity, and maximize the offsetting of eddy current loss, the conductor is provided with seven wires, one in the inner layer and six in the outer layer.

[0009] In order to reduce the amount of conductor materials used, achieve lightweight optimization of equipment, and reduce eddy current loss in leakage magnetic field while ensuring the current carrying capacity and structural strength of the winding, the diameter of the conductor is 0.6mm-1.2mm.

[0010] In order to construct a layered insulation encapsulation structure, forming an independent annular winding and heat dissipation space, and to achieve weight reduction and energy saving of the equipment, the encapsulation body includes an inner encapsulation and an outer encapsulation, which form an annular inner cavity. The inner encapsulation is set close to the axis, and the electromagnetic coil is wound between the inner encapsulation and the outer encapsulation.

[0011] In order to adapt to the support performance of the outer enclosure of the electromagnetic coil, and to reduce the overall weight while meeting the sealing performance requirements, thereby effectively reducing the overall weight and production cost of the equipment, the thickness of the outer enclosure along the radial direction is smaller than the thickness of the inner enclosure along the same direction.

[0012] In order to fill the tiny gaps generated during the winding of the electromagnetic coil, enhance the insulation and sealing of the outer side of the coil, avoid local electric field concentration, and further reduce equipment operating losses, a gap-filling layer is provided between the electromagnetic coil and the outer enclosure, which is coated on the outside of the electromagnetic coil after the electromagnetic coil is wound.

[0013] In order to quickly dissipate the heat generated by the coil operation, improve the problem of uneven temperature rise and poor heat dissipation of the equipment, effectively reduce eddy current loss under high temperature conditions, and reduce the amount of electromagnetic coil used, the encapsulation body is made of high thermal conductivity resin material.

[0014] The beneficial effects of this invention are as follows: This invention is a novel low-loss, lightweight ultra-high voltage reactor. This solution differs from traditional reactors by employing a multi-strand double-layer stranded structure, combined with a tightly wound method where multiple electromagnetic wires are pressed into rectangular cross-sections. This reduces eddy current losses generated by the magnetic field, balances coil temperature rise, and, with the support of the electromagnetic coil's circumference encapsulation, utilizes a differentiated thickness inner and outer encapsulation structure design. This reduces the outer encapsulation thickness while ensuring the inner layer's insulation protection strength, thus reducing insulation material consumption and overall equipment weight. Furthermore, the encapsulation body uses a high thermal conductivity resin material, combined with a sealed filling structure on the outer side of the coil, effectively improving overall heat dissipation efficiency and structural density, avoiding problems such as heat accumulation in gaps and uneven heat dissipation, enhancing long-term operational stability, and reducing the weight of the electromagnetic coil and the overall reactor weight without changing the temperature rise. Attached Figure Description

[0015] The solutions and advantages of this application will become clear to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0016] In the attached diagram: Figure 1 This is a schematic diagram of the main structure of the winding; Figure 2 This is a cross-sectional view of a single-layer encapsulation. Figure 3 This is a schematic diagram of a portion of an electromagnetic coil; The components represented by the various reference numerals in the diagram are: 1. Winding body; 2. Encapsulation body; 21. Annular inner cavity; 22. Electromagnetic wire; 221. Conductor; 222. Insulation layer; 23. Sealing layer; 24. Inner encapsulation; 25. Outer encapsulation. Detailed Implementation

[0017] Exemplary embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. It should be noted that these embodiments are provided to enable a more thorough understanding of this disclosure and to fully convey the scope of this disclosure to those skilled in the art. This disclosure can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0018] Example This embodiment discloses a novel low-loss, lightweight UHV reactor. Unlike existing traditional dry-type air-core reactors, which are significantly affected by the skin effect and proximity effect, resulting in high eddy current losses and a significant increase in AC resistance under high-frequency operating conditions, traditional reactors use a large amount of redundant conductor 221 to balance winding current and ensure insulation sealing strength. The inner and outer sheaths 25 adopt a uniform insulation thickness structure, resulting in a large overall consumption of insulation materials and winding consumables, leading to a large equipment weight and limited heat dissipation performance. This solution optimizes the stranded structure of the electromagnetic wire 22, changes the sheath thickness and material, and fills the gaps in the 22 turns of electromagnetic wire to achieve multiple optimizations, including effectively reducing winding eddy current losses, reducing overall equipment weight, and improving heat dissipation efficiency. This significantly improves the operational stability and economy of the UHV reactor.

[0019] This low-loss, lightweight, novel ultra-high voltage reactor comprises two sets of star-shaped frames arranged symmetrically at intervals. These two sets of star-shaped frames serve as end supports and conductive connection structures for the winding body 1. The structure boasts high strength and stable conductivity, meeting the load-bearing and connection requirements of ultra-high voltage and high-current operating conditions. The winding body 1 is fixedly assembled between the two sets of star-shaped frames. The structure of the star-shaped frames and their installation with the winding body 1 are well-known technologies in the field, such as the interchangeable assembly structure dry-type air-core reactor (patent number CN209708801U), and will not be elaborated further. Figure 1 The winding body 1 includes multiple cylindrical encapsulation bodies 2 with through openings at the top and bottom. The multiple encapsulation bodies 2 are arranged coaxially and nested with each other at intervals along the radial direction to form a multi-layer hollow nested winding structure. The overall structure is regular and the stress is uniform.

[0020] In this embodiment, the single encapsulation body 2 is a cylindrical structure with an annular inner cavity 21 inside. An electromagnetic wire 22 turns are wound inside the annular inner cavity 21. The electromagnetic wire 22 turns are formed by winding multiple electromagnetic wires 22. Each electromagnetic wire 22 is formed by twisting multiple conductors 221 into a strand. The stranded conductors 221 are covered with an insulation layer 222. Compared with the traditional solid conductor 221, the multi-strand stranded structure can effectively weaken the skin effect, significantly reduce eddy current loss and AC resistance increase under high-frequency operating conditions, and effectively alleviate the coil heating problem.

[0021] In addition, combined Figure 2 and Figure 3The single electromagnetic wire 22 preferably adopts a double-layer arrangement structure with seven conductors 221. The inner layer has a central conductor 221, and the outer layer has six conductors 221 evenly arranged around the central conductor 221. The double-layer winding structure has uniform twisting, strong structural stability, and good electromagnetic distribution consistency. It can further balance the current density of the conductors 221, avoiding local overheating and increased loss caused by local current concentration, and is suitable for ultra-high voltage, high-capacity continuous operation. The diameter of a single conductor 221 is between 0.6mm and 1.2mm, and the smallest single conductor 221 can be as small as 0.6mm. This reduces eddy current loss generated in the leakage magnetic field while maintaining the same DC resistance loss. Compared with conventional transposed wire products, eddy current loss can be reduced by 40%-60%, and the coil weight is reduced by 3%-7%.

[0022] In this design, the 22 turns of electromagnetic wire consist of 8-12 electromagnetic wires 22, which are tightly wound together. Each electromagnetic wire 22 is closely fitted and pressed together without any gaps. The multiple electromagnetic wires 22 are processed by a re-twisting and pressing process, so that the overall cross-section of the electromagnetic wire 22 is formed into a regular rectangular structure. Compared with traditional round stranded wire, the rectangular cross-section electromagnetic wire 22 can significantly improve the winding compactness, effectively reduce the overall space occupied by the winding, reduce the amount of redundant consumables in the winding, and realize the lightweight design of the equipment. At the same time, the regular rectangular tight arrangement structure can make the winding current distribution more uniform, further equalize the temperature rise in each area, and improve the overall heat dissipation uniformity and operational stability.

[0023] Based on the above structure, combined with Figure 2 Each encapsulation 2 comprises an inner encapsulation 24 and an outer encapsulation 25. The inner encapsulation 24 is positioned closer to the winding axis, and the inner encapsulation 24 and the outer encapsulation 25 form an annular inner cavity 21. 22 turns of electromagnetic wire are wound and arranged between the inner encapsulation 24 and the outer encapsulation 25, achieving all-around insulation protection and structural support through double-layer encapsulation. To meet the requirements of lightweighting and heat dissipation optimization, unlike traditional equal-thickness encapsulation structures, the outer encapsulation 25 is supported by 22 turns of electromagnetic wire on its inner side. While meeting the sealing performance requirements, the thickness of the outer encapsulation 25 is optimized by setting its radial thickness to be less than that of the inner encapsulation 24. This effectively reduces the amount of outer insulating resin used, further reducing the overall weight of the equipment. Simultaneously, the thin-walled outer encapsulation 25 facilitates the outward conduction and dissipation of coil heat, significantly improving overall heat dissipation efficiency and addressing the problems of poor heat dissipation and high temperature rise in traditional reactors.

[0024] In this embodiment, after the 22 turns of electromagnetic wire are wound, a filler layer 23 is applied between the outer side of the 22 turns of electromagnetic wire and the inner side of the outer enclosure 25. A single-component epoxy resin paste is preferred. After curing by heat, the filler layer 23 effectively fills the tiny gaps, inter-turn voids, and coils generated after the electromagnetic wire 22 is wound, improving the overall sealing and structural integrity of the winding. Furthermore, the enclosure 2 in this solution is integrally molded from a high thermal conductivity resin material, preferably bisphenol A epoxy resin. Compared to traditional general-purpose epoxy resins, it has superior thermal conductivity and insulation stability, enabling rapid heat dissipation from the coil, effectively reducing the overall temperature rise of the winding, suppressing the increase in AC resistance, reducing the amount of electromagnetic wire used, and further reducing equipment operating losses.

[0025] This solution integrates and optimizes the structure of multi-strand double-layer twisted rectangular pressed electromagnetic wire 22, multi-layer nested coaxial winding, inner and outer differential thickness high thermal conductivity resin encapsulation, and outer gap filling and reinforcement structure. It simultaneously improves electromagnetic loss, structural weight, and heat dissipation performance, effectively solving the problems of high eddy current loss, high operating energy consumption, redundant winding materials, large equipment weight, uneven heat dissipation, and high temperature rise of traditional UHV dry-type air-core reactors.

Claims

1. A novel low-loss, lightweight ultra-high voltage reactor, comprising two sets of star-shaped frames arranged vertically at intervals, characterized in that, A winding body (1) is provided between the two sets of star-shaped frames. The winding body (1) includes multiple vertically penetrating openings and cylindrical encapsulation bodies (2). The multiple encapsulation bodies (2) are coaxial and nested at intervals along the radial direction. Each of the encapsulation bodies (2) is provided with an annular inner cavity (21), and an electromagnetic wire (22) is wound inside the annular inner cavity (21). The electromagnetic wire (22) includes multiple electromagnetic wires (22), and each electromagnetic wire (22) includes multiple stranded conductors (221), and the multiple conductors (221) are covered with an insulating layer (222).

2. The low-loss, lightweight novel ultra-high voltage reactor according to claim 1, characterized in that, Each of the electromagnetic wires (22) is arranged to abut against the adjacent electromagnetic wires (22), and the multiple electromagnetic wires (22) are twisted and pressed into a rectangular cross section.

3. The low-loss, lightweight novel ultra-high voltage reactor according to claim 1, characterized in that, The electromagnetic wires (22) are provided in 8-12 strands.

4. The low-loss, lightweight novel ultra-high voltage reactor according to claim 1, characterized in that, The multiple conductors (221) are arranged in a double layer, with at least one central conductor (221) in the inner layer and the outer layer evenly distributed around the central conductor (221).

5. A novel low-loss, lightweight ultra-high voltage reactor according to claim 4, characterized in that, The conductor (221) has seven wires, with one wire in the inner layer and six wires in the outer layer.

6. A novel low-loss, lightweight ultra-high voltage reactor according to claim 1, characterized in that, The diameter of the conductor (221) is 0.6mm-1.2mm.

7. A novel low-loss, lightweight ultra-high voltage reactor according to claim 1, characterized in that, The encapsulation body (2) includes an inner encapsulation (24) and an outer encapsulation (25), forming an annular inner cavity (21) between them. The inner encapsulation (24) is positioned close to the axis, and the electromagnetic wire (22) is wound around the inner encapsulation (24) and the outer encapsulation (25).

8. A novel low-loss, lightweight ultra-high voltage reactor according to claim 7, characterized in that, The outer encapsulation (25) has a radial thickness that is less than the inner encapsulation (24) in that direction.

9. A novel low-loss, lightweight ultra-high voltage reactor according to claim 7, characterized in that, A filler layer (23) is provided between the electromagnetic wire (22) coil and the outer enclosure (25), which is coated on the outside of the electromagnetic wire (22) coil after the electromagnetic wire (22) coil is wound.

10. A novel low-loss, lightweight ultra-high voltage reactor according to claim 1, characterized in that, The encapsulation body (2) is made of high thermal conductivity resin material.

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