A high-voltage and large-capacity ring-type air-core reactor support structure

Abstract

The present invention relates to a support structure for a high-voltage and large-capacity annular hollow reactor. It comprises a plurality of support plates, a bottom plate, a plurality of insulating pillars, a base, an annular comb plate and a support ring; a plurality of coils are wound on the horizontally arranged comb plate, and the plurality of coils form a coil; the support plate is vertically arranged and connected to the comb plate, and is used to bear the gravity of the comb plate and the coils thereon; the support plate is fixed to the horizontally arranged bottom plate; the support ring is located on the inner side of the coil; the insulating pillars are fixedly connected under the bottom plate and the support ring; the insulating pillars are fixed to the base. The coil of the annular hollow reactor proposed by the present invention can be wound as a whole, which can prevent the coil from being excessively deformed, and has a large heat dissipation area, meeting the application requirements of high voltage and large capacity.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power systems, and in particular to a high-voltage and large-capacity annular air-core reactor support structure applied to an offshore wind farm booster substation / DC converter station platform. Background Art

[0002] The column-type air-core reactor has mature technology and simple structure, and is widely used in power systems. For example, in the application scenario of the DC converter station platform of offshore wind farms, it is mainly the bridge arm reactor and the smoothing reactor connected in series on the pole line, which are generally dry column-type hollow structures. However, the magnetic field generated by the existing high-voltage and large-capacity column-type air-core reactor during operation may cause magnetic field interference to the surrounding auxiliary equipment, induce eddy currents in the metal structure and metal plate in the closed space of the platform, and cause serious heating. Especially when the equipment needs to be compactly arranged, such as the booster substation / DC converter station platform of offshore wind farms, the demand for low magnetic clearance reactors is more prominent and urgent. The concept of the ring-type air-core reactor comes from the spiral wound ring. During operation, the magnetic field is only distributed inside the reactor, which is more suitable for application sites where the equipment is compactly arranged. This high-voltage, large-capacity, low magnetic clearance reactor occupies less space, optimizes the electromagnetic environment in space, and can bring significant comprehensive benefits. The ring-type air-core reactor confines the magnetic field inside the reactor equipment, which can solve the external magnetic field problem of the air-core reactor from the source. Although the prior art has proposed the concept of annular air-core reactors, as a new type of high-voltage and large-capacity power equipment, its supporting structure has not yet been studied in detail, and no related products have been released.

[0003] The high-voltage and large-capacity annular air-core reactor is composed of multiple coils connected and arranged in an annular direction. The cross-section of the coil can be circular, rounded rectangular, or racetrack-shaped, including the D-shaped coil used in the Tokamak device. Figure 1 As shown, the coil of the annular air-core reactor is composed of circular cross-section coils. The "coil" of the annular air-core reactor is composed of several "coil" units arranged in a ring direction and connected in series or in parallel. High-voltage and large-capacity reactors should be characterized by fully enclosed windings. If the manufacturing method of independently winding coils and then assembling them is adopted, the integrity of the coil is poor, and the defects at the connection of the coils and the deviation of the installation position are difficult to guarantee. Under the application conditions of high-voltage and large-capacity reactors, the supporting structure that meets the short-circuit electrodynamic conditions needs to be reasonably designed. In addition to gravity, in the magnetic field inside the annular air-core reactor, the combined force of the Ampere force on each coil points to the center axis of the reactor. At the same time, the Ampere force on the conductors at different positions of the coils has different magnitudes and directions, which manifests as uneven expansion force. In the attached Figure 2In the diagram, arrows of different lengths indicate the magnitude and direction of the Ampere force on the conductor per unit length (arc segments are unit radians) at different locations. The magnetic field is stronger near the center axis, and the Ampere force on the conductor is greater. In addition to tensile force, the conductor is also subject to bending moment. Therefore, in addition to considering the resultant force on the coil as a whole, it is also necessary to consider the deformation of the conductor caused by uneven expansion force to prevent excessive deformation from causing insulation rupture and insulation failure. During the operation of the reactor, short circuits in wire turns can cause serious fire accidents.

[0004] In the prior art, CN110676033A proposes to use insulating pads to separate the coils to form an insulated and heat-dissipating airway, and to set insulating struts on the inner side of the reactor coil to offset the centripetal force generated by all the coils of the annular hollow reactor. The centripetal force here refers to the resultant Ampere force directed toward the central axis of the annular hollow reactor, which is different from the concept of centripetal force corresponding to the circular motion of an object. The insulating pads and insulating struts of the prior art are tied together with the coils. CN111430134A proposes to install the coils in a horizontal fixed plate, and to open fixed grooves matching the number and thickness of the coils at corresponding positions of the fixed plate. CN110993286A proposes a reactor unit structure in which a conductor is wound on an annular insulating frame, and a plurality of reactor units are combined in series / parallel to form a high-voltage, large-capacity, low-magnetic clearance reactor.

[0005] The problems with the support structure of the above-mentioned high-voltage and large-capacity annular hollow reactor proposed in the prior art are as follows: 1. The coil is not convenient for overall winding. 2. The stress conditions of the electromotive force under short-circuit conditions cannot be met at the overall level of the reactor. 3. The deformation problem of the coil conductor is not solved. After the coil is wound separately, it is assembled and connected into an annular hollow reactor. In this way, the integrity of the coil is poor, and the defects at the connection of the coil and the deviation of the installation position are difficult to guarantee. The short-circuit fault current of the reactor usually reaches more than ten times the rated current, and the magnitude of the electromotive force is proportional to the square of the current. If the annular hollow reactor does not have a reasonable support structure, it cannot meet the application requirements of high voltage and large capacity. In the annular structure, the conductor is in an uneven magnetic field, and the magnetic field is stronger near the central axis, and the expansion force on the conductor is greater. Therefore, in addition to considering the gravity and Ampere force at the overall level of the coil, it is also necessary to consider the deformation problem caused by the uneven expansion force of the coil to prevent the wire from deforming too much, causing the turn insulation to rupture and then cause inter-turn short circuit. Iryna MAZURENKO Andriy PAVLYUK YuriyVASETSKY.Parameters of Superconducting Magnets with Racetrack-Shaped Coilsand Support Structure Placed Inside Torus[J].Przeglad Elektrotechniczny,2012(3a) A racetrack-shaped coil shape is proposed for superconducting energy storage annular magnets. A support tube and a support ring are used inside the coil to offset the centripetal force, and spokes are used inside the coil section to fix the coil shape. However, the structure is complex and it is difficult to directly apply it to high-voltage and large-capacity annular air-core reactor equipment. In summary, the realization of high-voltage and large-capacity annular air-core reactors faces the problem of supporting and fixing the coils.

[0006] How to overcome the shortcomings of the above-mentioned existing technical solutions, solve the problems of discontinuous coil winding and uneven expansion force causing wire deformation when using annular air-core reactors, and improve the capacity limit of this new structural reactor equipment has become an urgent issue to be solved in this technical field. Summary of the invention

[0007] In order to overcome the shortcomings of the above-mentioned prior art, in view of the above-mentioned technical problems, according to the three-dimensional force analysis and characteristics of the coil, the present invention proposes a support structure or implementation method for a high-voltage and large-capacity annular air-core reactor. The specific technical solution is as follows:

[0008] A high-voltage and large-capacity annular hollow reactor support structure comprises a plurality of support plates, a bottom plate, a plurality of insulating pillars, a base, an annular comb plate and a support ring;

[0009] A plurality of coils are wound on the horizontally arranged comb-shaped plate, and the plurality of coils form a coil;

[0010] The support plate is vertically arranged and connected to the comb-shaped plate, and is used to bear the gravity of the comb-shaped plate and the wire cake thereon;

[0011] The support plate is fixed on the horizontally arranged bottom plate;

[0012] The support ring is located inside the coil;

[0013] The insulating pillar is fixedly connected below the bottom plate and the support ring;

[0014] The insulating support is fixed on the base.

[0015] Furthermore, rectangular grooves are provided on the edge of the comb plate, the number and position of the rectangular grooves are consistent with those of the wire coils, and the wire coils are wound in the corresponding rectangular grooves; a plurality of radial straight grooves are provided on the comb plate, and the support plate is connected to the comb plate through the straight grooves.

[0016] Furthermore, the comb plate includes a plurality of fan-shaped parts, and the plurality of fan-shaped parts are spliced ​​and combined into a horizontal ring structure.

[0017] Furthermore, the support ring is composed of an outer edge, an inner edge and a plurality of spokes connecting the two; the outer edge is insulated contact with the coil; the plurality of spokes are evenly distributed around the circumference of the inner edge to transmit force, and the support ring is fixed to the insulating support via the inner edge connection.

[0018] Furthermore, the cross-sectional shape of the coil forming the coil is circular, track-shaped, rounded rectangular, or D-shaped; and the outer shape of the outer edge matches the shape of the inner side of the coil.

[0019] Furthermore, the support rings are composed of a plurality of fan-shaped parts spliced ​​together.

[0020] Furthermore, a straight slot corresponding to the comb plate is provided on the bottom plate for fixing the support plate; the bottom plate is annular and includes a plurality of fan-shaped parts, and the plurality of fan-shaped parts are spliced ​​and combined into a horizontal annular structure.

[0021] Furthermore, an inner coil hoop and an outer coil hoop are respectively provided on the inner and outer sides of the coil bobbin, and their shapes are the same as the cross-sectional shape of the coil bobbin. The inner coil hoop and the outer coil hoop are in direct contact with the comb plate and the support ring.

[0022] Furthermore, an elastic binding belt is bounded on the outside of the wire coil. For a wire coil with a circular cross-section, the binding belt passes through the center of the cross-section of the wire coil; for a wire coil with a runway cross-section, the binding belt is located at the straight section of the wire coil.

[0023] Furthermore, a plurality of layers of annular comb plates are arranged in the coil, and the support plate is fixedly connected to the plurality of layers of annular comb plates at the same time.

[0024] The technical solution of the present invention has achieved the following beneficial effects: 1. A combination of internal and external support of the coil is adopted. The coil is wound as a whole on an annular comb plate, and the annular comb plate bears the gravity and part of the Ampere force of the coil. The integrity of the coil is good, which ensures the deviation of the installation position of the coil. 2. The support ring is used on the inner side of the annular air-core reactor to offset the centripetal force generated by the coil, thereby ensuring the stability of the overall level of the annular air-core reactor. The results of three-dimensional stress analysis show that the support ring structure can reduce the stress generated by the short-circuit electric force in the coil by about half. 3. In order to solve the problem of conductor deformation caused by uneven expansion force, the present invention adds high-strength and rigidity coil hoops on the inner and outer sides of each coil to maintain the shape of the coil and prevent the conductor from being deformed and damaged. The coil hoop is in direct contact with supports such as annular comb plates or support rings, so that the stress distribution of the coil is more uniform. 4. The present invention uses binding belts to constrain the expansion of the coil, which is particularly suitable for the problem of conductor deformation in the straight section of the runway-shaped cross-section coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an overall schematic diagram of a ring-type air-core reactor coil in the prior art.

[0026] Figure 2 The diagram is a schematic diagram of the Ampere force at different positions of the coil of a ring-type air-core reactor in the prior art.

[0027] Figure 3 It is a schematic diagram of a sector-shaped portion of the annular comb plate of the present invention.

[0028] Figure 4 This is a schematic diagram of the support ring structure of the present invention.

[0029] Figure 5 It is a schematic diagram of the inner and outer coil hoops and the binding belt of the present invention.

[0030] Figure 6 This is an example of the support structure of a single coil of the present invention.

[0031] Figure 7 It is a schematic diagram of the overall appearance of the ring-type air-core reactor of the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings. The following examples are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the scope of protection of the present invention. It should be pointed out that the following detailed descriptions are all exemplary and are intended to provide further explanation of the present application.

[0033] Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which this application belongs. It should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0034] The embodiment of the present invention relates to a high voltage and large capacity annular air core reactor support structure. Figure 7 As shown, the support structure includes a plurality of support plates 2 , a bottom plate 3 , a plurality of insulating pillars 4 , a base 5 , an annular comb plate 6 and a support ring 12 .

[0035] As attached Figure 3 As shown, the comb plate 6 is a horizontal annular structure, which is placed inside the annular air-core reactor coil. The coil is wound as a whole on the comb plate 6, and the comb plate 6 bears the gravity and part of the Ampere force of the coil. The annular comb plate 6 is spliced ​​by multiple fan-shaped structures, which is convenient for coil winding. Rectangular grooves 7 are provided on the edge of the comb plate 6. The number and position of the rectangular grooves 7 are consistent with those of the coil 1. The coil 1 is wound in the corresponding rectangular grooves 7, ensuring the tolerance of the installation position. There are several radial straight notches 8 on the comb plate 6, and the straight notches 8 are connected to the vertical support plate 2.

[0036] In another preferred embodiment, a partial coil may be wound first, and then a sector-shaped portion of the annular comb plate 6 is extended into the coil from the maximum inner diameter of the bobbin 1, and then the comb plate 6 is moved up and down and fixed to a corresponding position.

[0037] A plurality of bobbins 1 are wound on the horizontally arranged comb plate 6, and the plurality of bobbins 1 form a coil.

[0038] Although the drawings in the specification of the present invention take the circular cross-section coil 1 as an example to describe and illustrate the supporting structure of the high-voltage and large-capacity ring-type air-core reactor coil, the present invention is also applicable to coils with runway-shaped cross-sections, rounded rectangular cross-sections and D-shaped cross-sections.

[0039] The support plate 2 bears the gravity of the annular comb plate 6 and the coil 1 thereon. The support plate 2 is fixed on the annular bottom plate 3. The bottom plate 3 is provided with straight slots 8 corresponding to the comb plate 6 for fixing the support plate 2. The entire annular air-core reactor is supported by a plurality of insulating pillars 4. The insulating pillars are fixed on the base 5.

[0040] As attached Figure 4As shown, the support ring 12 is located on the inner side of the annular air-core reactor coil to bear the centripetal force generated by the coil. The support ring 12 is composed of its outer edge 13, inner edge 15, and a radial plate 14 connecting the two. The outer edge 13 is insulated and in contact with the coil 1, and its outer shape matches the shape of the inner side of the coil. For example, for a coil with a circular cross-section, the outer shape of the support ring is a concave arc that fits the inner side of the coil; for a coil with a runway-shaped cross-section, the outer shape of the support ring includes a straight line and two arcs. Several radial plates 14 are evenly distributed on the circumference to transmit the force, and the typical number is 8, 12, etc. The support ring 12 as a whole can be connected and fixed on the insulating support 4 through the inner edge 15. The support ring 12, the comb plate 6, and the bottom plate 3 can all be combined by a number of fan-shaped parts, which is convenient for the manufacture of the reactor. The support ring 12 ensures the stability of the coil at the overall level. A support ring 12 is used inside the reactor to bear the Ampere force of the coil, ensuring the overall stability of the reactor coil and reducing the maximum stress caused by the short-circuit electric force in the wire cake. The three-dimensional stress analysis results show that the support ring structure can reduce the stress generated by the short-circuit electric force in the wire cake by about half.

[0041] The annular comb plate 6, the support plate 2, the bottom plate 3 and the support ring 12 can all be made of FR4 or other insulating materials.

[0042] As attached Figure 5 As shown, in order to solve the problem of wire deformation caused by uneven expansion force, the present invention adds inner and outer coil hoops 10 and 11 on the inner and outer sides of the wire coil 1. The inner and outer coil hoops 10 and 11 have high strength and rigidity to maintain the shape of the wire coil 1 and reduce the maximum stress of the wire coil 1. The inner and outer coil hoops 10 and 11 are located on the outer circumference and inner circumference of the wire coil 1, and are in direct contact with the annular comb plate 6, the support ring 12 or other supports, so that the wire is more evenly subjected to the reaction force of the support structure, which can prevent the wire from being deformed and damaged, and can also reduce the maximum stress in the wire coil 1. The inner and outer coil hoops 10 and 11 are integrated with the wire coil 1 during the coil winding process. The shape of the inner and outer coil hoops 10 and 11 is the same as that of the wire coil 1.

[0043] In a preferred embodiment of the present invention, a binding belt 9 is used to constrain the expansion of the coil 1. The binding belt 9 is located outside the coil 1 and generally passes through the center of the cross section of the coil 1. The binding belt can be made of a compression belt or other materials, preferably flame retardant materials and high-strength materials. The binding belt 9 is particularly suitable for preventing the deformation of the straight section of the coil with a runway-shaped cross section. An example of the relationship between the coil, the coil hoop, and the binding belt is shown in the attached figure. Figure 5 shown.

[0044] Attached Figure 6Indicates that a portion of the toroidal air-core reactor is cut off to intuitively describe the support structure of the coil. In a preferred embodiment of the present invention, two layers of annular comb plates 6 are arranged in the coil 1, and the two layers of annular comb plates 6 are respectively located on both sides of the binding belt 9, and the support plate 2 is fixedly connected to the two layers of annular comb plates 6 at the same time.

[0045] In view of the structural problems faced by the practical application of high-voltage and large-capacity annular air-core reactors, the present invention proposes a method that combines internal and external coil supports. The coil of the annular air-core reactor proposed in the present invention can be wound as a whole, remains stable under the condition of short-circuit electromotive force, and can prevent the coil from being excessively deformed. While meeting the stress conditions, the overall heat dissipation area of ​​the annular air-core reactor is also large, meeting the application requirements of high voltage and large capacity. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and deformations can be made without departing from the technical principles of the present invention, and these improvements and deformations should also be regarded as the scope of protection of the present invention.

Claims

1. A high-voltage and large-capacity ring-type air-core reactor support structure, characterized in that: The support structure comprises a plurality of support plates (2), a bottom plate (3), a plurality of insulating pillars (4), a base (5), an annular comb plate (6) and a support ring (12); A plurality of coils (1) are wound on the comb-shaped plate (6) arranged horizontally, and the plurality of coils (1) form a coil; The support plate (2) is vertically arranged and connected to the comb-shaped plate (6), and is used to bear the gravity of the comb-shaped plate (6) and the wire cake (1) thereon; The support plate (2) is fixed on the horizontally arranged bottom plate (3); The support ring (12) is located inside the coil; The insulating pillar (4) is fixedly connected below the bottom plate (3) and the support ring (12); The insulating support (4) is fixed on the base (5).

2. The high-voltage and large-capacity ring-type air-core reactor support structure according to claim 1 is characterized in that: The edge of the comb-shaped plate (6) is provided with rectangular grooves (7), the number and position of the rectangular grooves (7) being consistent with those of the wire coils (1), and the wire coils (1) are wound in the corresponding rectangular grooves (7); the comb-shaped plate (6) is provided with a plurality of radial straight notches (8), and the support plate (2) is connected to the comb-shaped plate (6) via the straight notches (8).

3. The high-voltage and large-capacity ring-type air-core reactor support structure according to claim 2 is characterized in that: The comb-shaped plate (6) comprises a plurality of fan-shaped parts, and the plurality of fan-shaped parts are spliced ​​and combined into a horizontal annular structure.

4. The high-voltage and large-capacity ring-type air-core reactor support structure according to claim 1 is characterized in that: The support ring (12) is composed of an outer edge (13), an inner edge (15) and a plurality of spokes (14) connecting the outer edge (13) and the coil (1) in an insulated manner; the plurality of spokes (14) are evenly distributed around the circumference of the inner edge (15) to transmit force, and the support ring (12) is connected and fixed to the insulating support pillar (4) via the inner edge (15).

5. The high-voltage and large-capacity annular air-core reactor support structure according to claim 4 is characterized in that: The cross-sectional shape of the coil (1) constituting the coil includes a circle, a racetrack, a rounded rectangle, and a D shape; the outer shape of the outer edge (13) matches the shape of the inner side of the coil.

6. The high-voltage and large-capacity ring-type air-core reactor support structure according to claim 1 is characterized in that: The support rings (12) are each formed by splicing and assembling a plurality of fan-shaped parts.

7. The high-voltage and large-capacity ring-type air-core reactor support structure according to claim 1 is characterized in that: The bottom plate (3) is provided with a straight notch (8) corresponding to the comb plate (6) for fixing the support plate (2); the bottom plate (3) is annular and comprises a plurality of fan-shaped parts, and the plurality of fan-shaped parts are spliced ​​and combined into a horizontal annular structure.

8. The high-voltage and large-capacity annular air-core reactor support structure according to claim 1 is characterized in that: An inner coil hoop (10) and an outer coil hoop (11) are respectively arranged on the inner side and the outer side of the coil bobbin (1), and the shapes thereof are the same as the cross-sectional shape of the coil bobbin (1). The inner coil hoop (10) and the outer coil hoop (11) are in direct contact with the comb plate (6) and the support ring (12).

9. The high-voltage and large-capacity ring-type air-core reactor support structure according to claim 1 is characterized in that: The outer side of the wire coil (1) is bound with an elastic binding belt (9); for a wire coil with a circular cross-section, the binding belt (9) passes through the center of the cross-section of the wire coil (1); for a wire coil with a runway cross-section, the binding belt (9) is located at the straight section of the wire coil (1).

10. The high-voltage and large-capacity ring-type air-core reactor support structure according to claim 9 is characterized in that: The wire coil (1) is provided with a plurality of layers of annular comb plates (6), and the support plate (2) is fixedly connected to the plurality of layers of annular comb plates (6).

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