AT528483A2 - Coil assembly for electrical power supply networks - Google Patents

Abstract

The invention relates to a coil assembly (1) for electrical power supply networks. This coil assembly (1) comprises a hollow cylindrical air-core choke coil (2) with a vertically extending coil axis (3), and a support structure (7) with an annular support body (10), which defines an upper support plane and which is arranged below a lower axial end (14) of the air-core choke coil (2) and is designed to support the air-core choke coil (2) in a load-bearing manner. The support structure (7) further comprises a plurality of column-like insulators (11), which are designed to provide electrically insulating and load-bearing support for the annular support body (10) and the air-core choke coil (2) against a ground foundation or a ground level (8). The annular support structure (10) comprises concrete (18), which serves as the material for providing the load-bearing, strength-relevant annular shape of the support structure (10), wherein the concrete (18) contains non-ferromagnetic reinforcement (19). This non-ferromagnetic reinforcement (19) comprises fibers, rods (20) and/or mats (21) made of at least one non-ferromagnetic material embedded in the concrete (18).

Description

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Description

[0001] The invention relates to a coil assembly for electrical power supply networks, as specified in the claims.

[0002] EP3357076B1 describes a frame for mounting a coil of an air-core reactor. The frame comprises a plurality of arms extending radially from a central hub, each arm having a free end. The frame further comprises a plurality of outer elements, each outer element being coupled to a corresponding pair of adjacent arms. The plurality of outer elements is made of a non-conductive material, and the plurality of arms are made of a material with sufficient mechanical and structural strength to support the weight of the coil. The corresponding outer element is coupled to the respective free ends of each pair of adjacent arms at a point offset from the free ends of each pair of adjacent arms. This frame, located between the electrical coil and the column-like insulators, is constructed as a complex truss structure with a plurality of metallic and dielectric profiles, depending on the static requirements.

[0003] US2228093A describes an electrical coil in which the electrical conductor for winding the coil is arranged and guided by several stacked insulating clamps. For this purpose, groove-shaped recesses are provided in the stacked insulating clamps to receive the electrical conductor. The insulating clamps space the conductor sections apart, thus preventing short circuits between windings. At each axial end of the electrical coil, a disc-shaped pressure plate made of reinforced concrete is formed, with the two pressure plates being clamped together by means of clamping screws, so that the stack of insulating clamps is resistant to displacement in both the axial and radial directions. This coil is supported above ground level by means of a plurality of electrical insulators. This design is also unsatisfactory with regard to its construction.

[0004] Furthermore, coil structures have been proposed in US2959754A, US2892168A, and GB262261A in which concrete is used to spatially organize and hold in position the electrical conductor for forming the electrical winding. These structures are also only partially satisfactory.

[0005] The object of the present invention was to overcome the disadvantages of the prior art and to create a coil design for integration into public or industrial power supply networks, which coil design offers a high degree of economic efficiency and yet ensures a high functional availability or security of supply.

[0006] This problem is solved by a coil assembly unit according to the claims.

[0007] The coil assembly according to the invention for electrical power supply networks comprises a hollow cylindrical air-core choke coil with a vertically extending coil axis. Accordingly, the air-core choke coil has an inner, substantially cylindrical air core. The coil assembly further comprises a support structure with an annular support body, which defines an upper support plane and which is arranged below a lower axial end of the air-core choke coil and is designed for load-bearing support of the air-core choke coil. The support structure further comprises a plurality of column-like insulators, in particular at least three column-like insulators, which are designed for electrically insulating and load-bearing support of the annular support body and the air-core choke coil against a ground foundation or a ground surface.

[0008] The annular support body for the separately or independently manufactured air-core choke coil 1 comprises concrete. In particular, the annular support body can be predominantly made of concrete, especially if it is composed of more than 70% by volume of concrete. Preferably, the proportion of concrete in the annular support body is between 80% and 99.9% by volume.

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% of the total volume of the annular support structure. The concrete for the annular support structure can consist at least predominantly of mineral materials, in particular an aggregate of various grain sizes and cement as a binder. The annular support structure is manufactured using flowable concrete, cast in form and subsequently hardened.

[0009] The concrete of the annular support structure, particularly in its hardened state, is used as a material to provide or create the load-bearing or load-absorbing ring shape of the support structure. In particular, the concrete forms the outer outline or basic shape of the annular support structure and makes a significant contribution to the static load-bearing capacity or mechanical strength of the annular support structure.

[0010] The concrete of the annular support structure contains non-ferromagnetic reinforcement, wherein this non-ferromagnetic reinforcement comprises fibers and/or rods and/or mats made of at least one non-ferromagnetic material embedded in the concrete. This non-ferromagnetic reinforcement is intended to increase the tensile strength of the concrete and/or to significantly increase the load-bearing capacity of the annular support structure in connection with mechanical tensile stresses acting on the annular support structure due to the mass of the air-core choke coil and external forces applied to the structure.

[0011] This makes it possible to support the ring-shaped support body, which is predominantly made of concrete, at specific points on a plurality of ring-shaped, column-like insulators relative to ground level, and to attach at least one high-mass air-core choke coil to the top of the ring-shaped support body, preferably also supporting it at at least three to approximately twelve points on the top of the ring-shaped support body. The vertical compressive strength of the ring-shaped support body is largely ensured by the inherently high compressive strength of concrete.

[0012] The non-ferromagnetic reinforcement significantly strengthens the concrete ring, especially in connection with achievable or occurring tensile loads during assembly and subsequent operation of the coil assembly. Nevertheless, during electrical operation of the coil assembly, its electrical losses are kept as low as possible because induced currents or eddy currents in the vicinity of the air-core choke coil, caused by the magnetic field of the air-core choke coil, are avoided or minimized. In particular, the low electrical conductivity of the concrete of the ring-shaped support structure and the non-ferromagnetic reinforcement embedded at least predominantly or completely within it promote the achievement of low electrical power loss and high mechanical stability of the coil assembly.

[0013] In particular, the ring-shaped support body or its concrete body can be designed to be closed in itself, i.e., to be endless, which can provide significant advantages with regard to the bending or torsional stiffness of the support body for the air core choke coil, without thereby causing increased electrical losses due to inductive couplings with the air core choke coil.

[0014] The electrical winding of the hollow cylindrical air-core choke coil is structurally and mechanically self-stabilizing. In particular, it comprises at least one hollow cylindrical winding layer, which includes turns of at least one electrical conductor held in position by synthetic resin and fabric tape reinforcements. Accordingly, the air-core choke coil is a prefabricated unit that can be supported and mounted on the supporting structure, in particular on its annular concrete support body. This also allows for a high degree of cost-effectiveness combined with high functional reliability of the coil assembly.

[0015] The non-ferromagnetic material for the reinforcement in the ring-shaped support body can be formed by a plastic material and/or by a glass fiber material and/or by a carbon material and/or by a textile material. These materials can be in the form of loose or interlinked fibers and added to the fresh concrete for the production of the ring-shaped support body.

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The concrete can be mixed with fiber-reinforced concrete (fiber-reinforced concrete), in which the non-ferromagnetic reinforcement is formed by preferably homogeneously distributed, non-ferromagnetic fibers within the concrete of the annular support structure. This enables the efficient production of annular support structures with different geometries or dimensions, particularly through concrete casting.

[0016] Alternatively or in combination with the measures described above, the non-ferromagnetic material can be made of stainless steel. This allows for the formation of high-strength annular support bodies which can be dimensioned accurately and reliably based on many years of experience and/or detailed investigations or standards. In particular, this allows for reliably achievable properties and long-term consistent stability of the annular support body.

[0017] The non-ferromagnetic material of the reinforcement can be in the form of bars and/or mats. This makes it possible to construct a long-term stable and functional annular concrete structure with internal reinforcement. In particular, this allows for advantageous use of extensive experience in general concrete construction with reinforcement, as well as the application of existing testing methods or standards relating to general concrete structures and concrete reinforcement.

[0018] The rods and/or mats made of non-ferromagnetic material, in particular plastic, glass or carbon fiber, textile, stainless steel and/or stainless steel, can be formed and/or assembled into so-called reinforcement cages and be cast or integrated at least predominantly into the concrete of the annular support structure. This ensures that the reinforcement is formed or remains positioned in the outer edge zones with respect to the cross-section of the annular support structure and can thus contribute significantly to a high tensile strength or flexural and fracture strength of the annular support structure.

[0019] According to an advantageous embodiment, the bars and/or mats can have a surface profile or surface structure, for example ribs, which surface profile is designed to create a positive-locking connection with the concrete enclosing the bars and/or mats. This allows interlocking between the reinforcement and the concrete to be achieved, thus improving the bond between the reinforcement and the concrete and ensuring good force transmission.

[0020] Alternatively or in combination with the aforementioned reinforcement cages, fiber mats made of glass fibers, carbon fibers, and/or textile fibers can be provided, which act as reinforcement in the concrete of the ring-shaped support structure, these fiber mats preferably having a grid-like structure. Such mat-reinforced concrete, for example, in the form of textile-reinforced concrete, enables the creation of ring-shaped concrete bodies with a relatively small cross-section while still maintaining high load-bearing capacity and stability. Also, due to the low density of such fiber mats compared to non-ferromagnetic steel or stainless steel, relatively lightweight yet robust ring-shaped support structures can be created. This offers advantages in terms of reduced material usage, economical transport, and the simplest possible lifting and assembly of the ring-shaped support structure.

[0021] Furthermore, it can be advantageous if the rods and/or mats run along the circumference of the annular support body, but do not form a closed electrical loop. This significantly improves the mechanical stability of the annular support body. At the same time, the electrical losses of the coil assembly can be kept to a minimum. In particular, this can significantly reduce electrical currents that would be caused by electromagnetic induction due to the alternating magnetic field of the air-core choke coil in the rods and/or mats of the concrete reinforcement. Such induced currents would manifest as detrimental heat loss from the annular concrete support body. Significant heat loss would also lead to a reduction in the mechanical strength of the reinforcement and, due to differing coefficients of thermal expansion, to

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This could lead to mechanical stresses in the ring-shaped support structure, which could impair long-term stability. These adverse effects can be significantly mitigated by the sophisticated measures implemented.

[0022] Furthermore, it can be provided that the ring-shaped support body is formed in one piece, in particular from cast concrete. This allows for small cross-sectional dimensions while still achieving high torsional stiffness. Furthermore, this eliminates or minimizes seams and joints, thereby reducing manufacturing costs.

[0023] Furthermore, the annular support body can be designed to be closed with respect to its circumference and to have a central annular space. This allows for high mechanical stability, in particular high torsional stiffness of the annular support body. Moreover, despite the closed annular shape of the support body, there are no disadvantages with regard to inductive coupling and the associated electrical energy losses. In addition, the central annular space ensures good cooling of the air-core choke coil by rising convection air.

[0024] At least on individual circumferential edges of the ring-shaped support body, chamfers or so-called chamfered edges can be formed. This can prevent chipping or edge breakage on the ring-shaped support body. In particular, this can improve the handling and robustness of the ring-shaped support body.

[0025] Another advantageous embodiment is one in which the annular support body has at least one internal cavity, in particular at least one cavity extending over the circumference of the ring. This allows for a significant weight reduction with only minor or negligible losses in the mechanical stability of the annular support body. Furthermore, this results in cost advantages because column-like insulators with relatively low load-bearing capacity can be used. In addition, this allows for increased stability and earthquake resistance of the coil assembly with minimal technical effort, thus saving weight.

[0026] The at least one inner cavity can be designed in a channel-like form, for example, in a ring shape. Or several interconnected or separate hollow chambers can be formed. These can be formed, for example, by so-called "concrete balloons," in particular defined by air- or gas-filled bellows or shells cast into the concrete. Alternatively or in combination, to reduce the weight of the ring-shaped concrete body, at least one body made of a lightweight material, for example, foam plastic, can be provided, which is at least partially cast into the concrete.

[0027] According to an advantageous embodiment, the upper support plane of the annular support body can be flat or planar, and/or the annular support body can have a flat or planar lower support plane. Accordingly, the annular support body does not have a circular or elliptical cross-section. This facilitates load-bearing support of the air-core choke coil at at least three to approximately twelve points on the upper surface of the annular support body and/or support of the annular support body against the column-like insulators.

[0028] Furthermore, it can be advantageous if the annular support body is tapered or narrowed in sections along its circumference with respect to its cross-section. Accordingly, the support body can have reduced cross-sectional dimensions in certain sections. This allows for a weight reduction of the annular support body without significantly affecting its torsional stiffness. This weight reduction, however, is accompanied by advantages with respect to the column-like insulators.

[0029] In particular, it can be provided that the annular support body has a first cross-sectional height and at least a second cross-sectional height along its ring circumference, and preferably the upper support plane for the air core choke coil is continuously adjustable.

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The design is flat. This allows for an increased vertical distance between the air-core choke coil and metallic parts of the supporting structure, such as mounting brackets or metallic head fittings of the column-like insulators, without significantly increasing the weight of the ring-shaped concrete support structure. In particular, this allows the electrical power loss of the coil assembly in connection with inductive coupling to be kept low in an efficient and weight-optimized manner.

[0030] Furthermore, it can be provided that the annular support body has a first cross-sectional width and at least a second cross-sectional width along its circumference, and preferably the upper support plane for the air-core choke coil is continuously variable or flat. This allows for the creation of a substantially gear-shaped or star-shaped circumferential contour of the annular support body. This enables a good ratio between low weight and high load-bearing capacity or torsional stiffness of the annular support body to be achieved. It also allows for good cooling or a chimney effect with respect to the lower axial end or with respect to any hollow cylindrical cooling channels between concentrically arranged winding layers of the air-core choke coil. Furthermore, this allows for a relatively wide and therefore stable support of the annular support body against a base surface. In particular, this allows for a simple yet effective increase in roll stability with low component mass.

[0031] According to one embodiment, the upper ends or head fittings of the column-like insulators are connected, in particular screwed, to a lower support plane of the annular support body. This allows the annular support body to rest stably on the upper ends or head fittings of the column-like insulators. Shear forces between the annular support body and the head fittings can be prevented due to the connection interface on the underside of the annular support body. Since the annular support body mechanically connects the column-like insulators to each other at their upper end sections, a high degree of mechanical stability can be achieved for this support structure.

[0032] An advantageous embodiment also includes several spaced-apart support feet, particularly in the form of support brackets, connected, especially screwed, to the lower axial end of the air-core choke coil with the preferably flat upper support surface of the annular support body. The support feet can have a vertical height or support height of between 30 mm and 200 mm. The number of these support feet can be between three and twelve, and in individual cases even more. This allows passive air cooling for the air-core choke coil based on natural convection. Furthermore, this creates a tolerance-compensating yet stable connection between the air-core choke coil and the annular support body made of concrete. These measures according to the claim are particularly effective when the air-core choke coil comprises at least two hollow cylindrical, concentrically positioned winding layers with at least one vertically extending air gap formed between them.

[0033] According to a further development, it is possible for the preferably metallic support feet between the air-core choke coil and the annular support body to be designed with a more elastically flexible or lower vertical stiffness compared to the vertical elasticity or stiffness of the annular support body. This allows for advantageous compensation of dimensional tolerances with respect to the annular concrete support body and/or with respect to the air-core choke coil. Adverse mechanical stresses between the aforementioned components can thus be prevented. Alternatively or in combination, vibration decoupling between the air-core choke coil and the annular concrete support body can be achieved. Vibrations occurring during the operation of the air-core choke coil, which are caused by electromagnetic forces, can thus be damped and/or frequency-filtered before being transmitted to the concrete of the annular support body. Depending on the amplitude-damping and/or frequency-

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The damping effect of the support feet can improve the fatigue strength and technical service life of the concrete body of the ring-shaped support structure and also of the air-core choke coil. For example, the support feet can have damping or spring-like damping and/or spring elements that act at least vertically, such as a plurality of disc springs.

[0034] Furthermore, it can be advantageous if the support feet are connected to the annular support body in a pull-off-resistant manner by means of concrete anchoring elements, which are anchored or can be anchored in the concrete of the annular support body, at positions along the circumference of the annular support body that are not predetermined, in particular at circumferential and/or radial positions that can be selected relatively freely by an installer. This also allows for advantageous compensation of dimensional tolerances between the air-core choke coil and the concrete body of the annular support body. In particular, the annular support body made of concrete and/or the at least one electrical winding layer of the air-core choke coil can advantageously be manufactured with higher dimensional tolerances. The measures according to the claim provide a more flexible mounting option in terms of position, and no fixed predefined mounting points on the top of the annular support body are required. This eliminates the need for a relatively complex, dimensionally accurate integration of metallic anchoring elements, such as retaining plates, into the concrete of the ring-shaped supporting structure.

[0035] The concrete anchoring elements can be formed, for example, by concrete anchoring screws or concrete tension anchor elements that are screwed, drilled, and/or bonded into the concrete of the supporting structure. Such connecting elements allow for a quickly produced yet high-strength connection of the support feet to the concrete body of the annular supporting structure.

[0036] According to an advantageous embodiment, metallic coupling brackets can be formed between the upper ends of the column-like insulators and the annular support body. These coupling brackets are designed for the mechanical, load-bearing connection between the upper ends of the column-like insulators and preferably the lower support plane of the annular support body. This makes it possible to create stable and mechanically optimal transition interfaces between the annular support body made of concrete and the column-like insulators. In particular, the concrete body of the annular support body can be kept geometrically simple, and any inclination or support angles of the column-like insulators deviating from the vertical can be robustly and practically implemented by the metallic coupling brackets. In particular, this makes it possible to provide a flat, horizontally oriented lower support plane when the annular support body is in operation.

[0037] Furthermore, the annular support body may include an electrically conductive polarizing conductor, which polarizing conductor is at least partially or completely embedded in the concrete of the annular support body. The polarizing conductor may be in the form of a strip or wire. Preferably, the polarizing conductor is integrated or embedded in the concrete of the annular support body with a predominant part of its surface. This allows for a high degree of prefabrication of the coil assembly and further facilitates simple and reliable assembly of the support structure for the air-core choke coil. The polarizing conductor, which is at least partially or completely embedded in the concrete, is thus well protected against mechanical damage and also against unwanted corrosion, which is particularly advantageous in environments with high humidity and/or in areas with high salt content in the ambient air, for example, near the sea.

[0038] The individual metallic coupling brackets can be connected in series by means of the electrically conductive polarity conductor, whereby the polarity conductor does not form a closed ring structure, but only extends over a partial section of the ring circumference of the annular support body made of concrete. This prevents electrical losses due to inductive coupling with the air-core choke coil. Furthermore, the polarity conductor can be provided for connection to an electrical terminal of the air-core choke coil, so that the

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The polarity conductor and the metallic coupling consoles are placed at a defined electrical potential.

[0039] According to an advantageous embodiment, the annular support body can have a polygonal shape with respect to its circumference, in particular a shape that is at least square to sixty-four-sided. This allows for the creation of a ring-shaped support body made of concrete that is sufficiently round to fit well against the cylindrical surface of the air-core choke coil, in particular to prevent protrusions of the outer corners of the support body, which is polygonal in the circumferential direction. Furthermore, this achieves a good compromise between roundness and the effort required for forming or molding the concrete body. Moreover, this allows the manufacturing costs of the annular support body made of concrete to be kept as low as possible. According to a practical embodiment, the annular support body can have a hexagonal outer and/or inner contour.

[0040] Furthermore, the annular support body can be designed in multiple parts, with the at least one joining plane between the joinable support body parts running radially and preferably parallel to an annular axis of the annular support body. In particular, the annular support body made of concrete can be composed of two or more ring segments. This allows for simpler and more cost-effective transport. In particular, lighter individual parts can be produced or individual parts with smaller dimensions can be provided. The corresponding individual parts can then be assembled relatively easily at the installation or operating location of the coil assembly unit to form the annular support body. The at least one radially and vertically extending separation or joining plane between the at least two ring segments or individual parts of the annular support body allows for the provision of annular support bodies made of concrete with an outer diameter of more than 2.5 meters, in particular between 2.5 meters and 4 meters, without incurring significant transport or logistics costs.

[0041] Furthermore, the annular support body can be provided with several cooling air channels or openings distributed around its circumference, extending between its underside and top surface, which are designed to allow cooling air or convection air to pass through. This ensures good cooling of the electrical winding of the air-core choke coil even with a relatively small vertical distance between the lower axial end of the winding or the hollow cylindrical partial windings and the top surface of the annular support body. In particular, this allows for relatively low support feet or winding stars to be formed between the underside of the electrical winding and the annular support body made of concrete, which offers advantages in terms of a low center of gravity for the coil assembly. The small vertical distance between the electrical winding of the air-core choke coil and the annular support body comprising concrete and its non-ferromagnetic reinforcement also minimizes inductive coupling and electrical energy losses of the coil assembly.

[0042] According to a practical embodiment, the annular concrete support body can have an axial height, measured between its upper and lower concrete support levels, of between 20 cm and 100 cm, preferably between 30 cm and 70 cm. This prevents electrical losses and heat generation in the metallic coupling brackets located between the insulators and the underside of the concrete ring or support body, as well as electrical losses and heat generation in the metallic head fittings of the insulators. In particular, this allows for greater vertical distances to the air-core choke coil.

[0043] When the axial height of the concrete ring of the annular support body reaches or exceeds a predetermined value, recesses or cutouts in the concrete body are advantageous to reduce weight. For example, recesses can be made on the underside of the annular

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The concrete body shall have several distributed support extensions made of concrete pointing downwards, which support extensions are intended for load-bearing support on the top of the column-like insulators.

[0044] For a better understanding of the invention, it is explained in more detail with reference to the following figures.

[0045] They show, in a highly simplified, exemplary representation:

[0046] Fig. 1 shows a coil assembly comprising an air core choke coil and a support structure for it in a perspective view from an oblique angle below;

[0047] Fig. 2 shows the coil assembly unit according to Fig. 1 in a perspective view from an oblique angle above;

[0048] Fig. 3 shows a reinforcement for the concrete of the ring-shaped supporting body in the supporting structure according to Figures 1 and 2;

[0049] Fig. 4 shows an embodiment of a ring-shaped support body constructed with concrete;

[0050] Fig. 5 shows a detailed view of the coil assembly according to Figures 1 and 2 in the area of the ring-shaped, concrete-built support body;

[0051] Fig. 6 shows another embodiment of a ring-shaped support body constructed with concrete;

[0052] Fig. 7 shows another embodiment of a ring-shaped support body constructed with concrete;

[0053] Fig. 8 shows a polygonal embodiment of a ring-shaped support body constructed with concrete.

[0054] By way of introduction, it should be noted that in the differently described embodiments, identical parts are provided with the same reference numerals or the same component designations, whereby the disclosures contained in the entire description can be applied analogously to identical parts with the same reference numerals or the same component designations. Furthermore, the positional indications chosen in the description, such as top, bottom, side, etc., refer to the figure directly described and illustrated, and these positional indications are to be applied analogously to the new position if the position is changed.

[0055] Figures 1 and 2 illustrate an embodiment of a coil assembly 1 for electrical power supply networks. An electrical power supply network includes publicly accessible supply networks as well as supply networks for industrial plants.

[0056] The coil assembly 1 comprises a substantially hollow cylindrical air-core choke coil 2. As is known per se, this air-core choke coil 2 can comprise a plurality of concentrically arranged, electrically parallel-connected winding layers—indicated in Fig. 7. Preferably, defined radial distances are provided between the outer and inner surfaces of immediately adjacent winding layers to form vertical, substantially hollow cylindrical cooling air channels, as can also be seen in Fig. 7. In the axial direction to these substantially hollow cylindrical cooling air channels, so-called spacer or gap strips can extend, which, among other things, contribute to a mechanically stable connection between the concentrically arranged winding layers. The air-core choke coil 2 defines a coil axis 3, which runs vertically in the operating state according to Figs. 1 and 2. In particular, the main or coil axis 3 of the essentially hollow cylindrical air core choke coil 2 runs in a vertical direction when the coil assembly 1 is in an operational assembly state, as illustrated in Figs. 1 and 2.

[0057] The diameter 4 of a central air core 5 of the air core choke coil 2 can be between 60% and 99%, in particular between 70% and 95% of an outer diameter 6 of the air core choke coil 2.

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[0058] The coil assembly 1 further comprises a support structure 7 for load-bearing support of the air-core choke coil 2 above a ground level 8, which can be defined, for example, by a base plate or by at least one foundation embedded in the ground. A support height 9 of the support structure 7, i.e., essentially a vertical distance of the air-core choke coil 2 from the ground level 8, can generally be between 100 cm and 1100 cm. This support height 9 depends primarily on a voltage potential (high voltage or extra-high voltage) applied to the air-core choke coil 2.

[0059] The mechanically and insulation-related support structure 7 comprises an annular support body 10. Preferably, this annular support body 10 is designed as a closed ring. The outer and/or inner circumferential contour of the annular support body 10 can be circular or polygonal. The free center or core area of the annular support body 10, hereinafter also referred to as the central annular space 25, can likewise be either circular or polygonal with respect to its circumferential direction. The central area of the annular support body 10 thus represents a free space or also an air core, the clear inner diameter of which can be at least approximately similar to the inner diameter 4 of the air core choke coil 2, i.e., similarly dimensioned, and in particular can lie in the range between -20% and +20% of the inner diameter 4 of the air core choke coil 2.

[0060] The support structure 7 further comprises a plurality of electrical insulators 11, which are designed or arranged in a column-like manner. These column-like insulators 11 are distributed along the ring circumference 31 of the support body 10 and thus define a support structure with at least three legs for the annular support body 10 and for the at least one air-core choke coil 2 supported thereon relative to the ground level 8. These column-like insulators 11 define individual support points for the annular support body 10 at their upper ends 38. The column-like insulators 11 can extend vertically and/or inclined with respect to the ground level 8. According to an embodiment not shown, several air-core choke coils 2 arranged one above the other in the axial direction, i.e., along the coil axis 3, can be provided.

[0061] The electrically insulating sections of the individual column-like insulators 11 can each comprise at least one support leg 12 at their end sections closest to the ground level 8, which is preferably made of metal. The upper ends 38 of the electrically insulating insulators 11 can each comprise a support bracket 13, hereinafter also referred to as coupling brackets 39, which are provided for the mechanical coupling of the electrically insulating insulators 11 with the annular support body 10. These support brackets 13 can also be made of metal, in particular designed as a metal structure, and represent a metallic coupling interface between the annular support body 10 made of concrete 18 and the column-like insulators 11.

[0062] The annular support body 10 is arranged below a lower axial end 14 of the air core choke coil 2 and is provided for load-bearing support or receiving the mass of the air core choke coil 2.

[0063] The air-core choke coil 2 can—as is known per se—have a lower winding star 15, which is located closest to the lower axial end 14, and an upper winding star 16, which is located closest to an upper axial end 17 of the air-core choke coil 2. The lower winding star 15 and/or the upper winding star 16 are generally defined by metallic profiles or flat profiles that are firmly connected to the winding of the air-core choke coil 2. Typically, the lower and upper winding star 15, 16 each define the electrical connections of the air-core choke coil 2. The winding stars 15, 16 can also serve to electrically connect the aforementioned electrical winding positions (Fig. 7) in parallel, which winding positions are usually arranged coaxially to each other and define the inductance and current-carrying capacity of the air-core choke coil 2.

10 / 28

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[0064] The annular support body 10 comprises hardened concrete 18 as its shaping material or base material. In particular, the annular support body 10 is predominantly formed by the mineral material concrete 18. Typically, the concrete content of the annular support body 10 can exceed 70%, and in particular can be between 80% and 99.9%, of the solid volume of the annular support body 10. The preferably cast concrete 18 is used as the material to provide the load-bearing, strength-relevant ring shape of the support body 10. In particular, the concrete 18 used contributes significantly to the external dimensions and mechanical properties, especially the strength and load-bearing capacity properties, of the annular support body 10. The mechanical properties, in particular the strength and load-bearing capacity properties of the annular support structure 10, are also enhanced by reinforcement 19, which is at least predominantly integrated into the concrete 18 and is thus indicated by dashed lines in Figures 1 and 2. In particular, the concrete 18 or the annular support structure 10 contains at least one non-ferromagnetic reinforcement 19, i.e., reinforcement 19 that causes no or no significant electrical losses due to induced eddy currents. This non-ferromagnetic reinforcement 19 can comprise fibers made of at least one non-ferromagnetic material embedded or mixed into the concrete 18, and/or bars 20 and/or mats 21 made of at least one non-ferromagnetic material, as schematically indicated by dashed lines in Figures 1 and 2.

[0065] The at least one non-ferromagnetic material of the concrete reinforcement 19 can be a plastic material and/or a glass fiber material and/or a carbon material and/or a textile material. Reinforcement 19 made of such a non-ferromagnetic material induces no or negligible electrical currents within the concrete 18 of the annular support body 10. This prevents or minimizes thermal losses or heating of the concrete 18 of the annular support body 10 as a result of the electromagnetic fields of the air-core choke coil 2 during its operation or operating state.

[0066] Alternatively or in combination, the at least one non-ferromagnetic material for the concrete reinforcement 19 can be made of stainless steel. This also results in induced eddy currents in the concrete reinforcement 19 of the annular support body 10 being low or negligible, so that no significant heating of the reinforcement 19 or of the annular support body 10 occurs during operation of the air-core choke coil 2.

[0067] As illustrated by way of example in Fig. 3, the non-ferromagnetic material of the reinforcement 19 can be in the form of bars 20 and/or mats 21. In particular, mats 21 can also be formed by a plurality of crossed bars 20, for example made of stainless steel, which can be flat or three-dimensional. According to the embodiment in Fig. 3, the reinforcement 19 for the annular support body 10 (Figs. 1, 2) can be designed as a cage-like ring. The respective reinforcement 19 is embedded in the concrete 18, in particular at least predominantly or completely encased by the concrete 18.

[0068] If the reinforcement 19 is formed by non-ferromagnetic bars 20 or mats 21, these can have a surface profile 22, such as transverse ribs known per se, as has been shown by way of example and partial indication in Fig. 3. Alternatively or in combination therewith, reinforcement 19 for the mineral-composed concrete 18 can also be achieved by fibers made of non-ferromagnetic materials mixed into the concrete 18, in particular by so-called fiber-reinforced concrete.

[0069] As also illustrated by way of example in Fig. 3, it is advantageous if the rods 20 and/or mats 21 extend along the circumference of the ring-shaped support body 10, but do not form a closed electrical loop. In particular, overlapping sections 23 of the ends of a ring-shaped rod 20 are electrically insulated from each other. Preferably, the end sections of a ring-shaped bent

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The bars 20 are not directly connected to each other, but are only coupled to each other via the electrically very poorly conductive or dielectric concrete 18. The same applies to reinforcement ring elements 24, which can be arranged transversely or radially to the ring circumference of the reinforcement 19 or the supporting body 10.

[0070] However, it may be advantageous if the body of the ring-shaped support body 10 formed from concrete 18 is closed or endless with respect to its ring circumference 31 in order to achieve high mechanical strength values and stability properties, in particular to achieve high torsional stiffness, as illustrated in Figs. 1 and 2.

[0071] The annular support body 10 defines an axially free, central annular space 25 (Figs. 1, 4), which can support a cooling effect for the air core choke coil 2 by ambient air or by air convection, in particular by a so-called chimney effect. In addition, this central annular space 25 makes it possible to reduce or keep as low as possible the mass of the annular support body 10 made of concrete 18.

[0072] According to the embodiment in Figs. 1 to 3, the concrete body of the ring-shaped support body 10 can in particular be formed in one piece, especially by means of molded concrete 18, whereby the ring-shaped support body 10 can offer high mechanical stability or strength.

[0073] According to the embodiment shown in Fig. 4, the annular support body 10 can also be designed in multiple parts, in particular being assemblable from a first support body part 26 and at least one further support body part 27. The at least one joining plane 28 between the joinable support body parts 26, 27 can extend radially and preferably parallel to an annular axis 29 of the annular support body 10. The individual support body parts 26, 27 are preferably connectable to form a one-piece, but multi-part, annular support body 10 by means of mechanical or positive-locking coupling elements, for example screws. The support body parts 26, 27 can be formed by ring segments, for example defined by joinable half-rings.

[0074] Independently of or in combination with this, it can be provided that the annular support body 10, or at least one of its support body parts 26, 27, has at least one internal cavity 30, in particular at least one cavity 30 extending over the ring circumference 31 or cavities 30 extending over sections of the ring circumference 31. The at least one cavity 30 is preferably free of concrete 18 and may contain air. However, it is also possible that the at least one concrete cavity 30 is at least partially or completely filled by a low-mass material, for example, foamed plastic or foam plastic, which material could be provided as a mold core during the manufacture or molding of the annular support body 10. So-called concrete balls or gas-filled tube bodies can also be provided as mold cores, which form the at least one cavity 30 in the molded, annular support body 10. Especially if at least one cavity 30 runs in the vicinity of the neutral fiber of the ring-shaped support body 10, the mass and mechanical stability of the ring-shaped support body 10 can be optimized.

[0075] As further schematically indicated in Fig. 4, an upper support plane 32 of the annular support body 10 can be designed as a flat surface. Alternatively or in combination with this, the annular support body can have a lower support plane 33 that is also designed as a flat surface. The upper support plane 32 is provided for receiving the mass or for introducing the load of the air-core choke coil 2 into the annular support body 10. The lower support plane 33 can be provided for transferring the mass or load of the toroidal choke coil 2 and the annular support body 10 to the column-like insulators 11 (Figs. 1 and 2).

[0076] The annular support body 10 can have a chamfer 34 on at least one of its boundary edges, which run along the ring circumference 31. This at least one

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The chamfer 34, or bevel, is dimensioned such that undesirable chipping of concrete 18 from the annular support body 10 is prevented during the assembly of the coil assembly unit 1 or during the assembly or transport of the annular support body 10. The annular support body 10 can have a substantially square or rectangular cross-section, preferably with a chamfer 34 formed along each of the four boundary edges, as illustrated by way of example in Fig. 4.

[0077] In Fig. 5, the ring-shaped support body 10 comprising concrete 18 is illustrated by way of example in its function as a mechanical interface element, which is arranged in the vertical direction between the air core choke coil 2 and the column-like insulators 11.

[0078] The air-core choke coil 2 can be connected to the upper support plane 32 of the annular support body 10 via several support feet 35 spaced apart from one another along the ring circumference 31, in particular by screws. The support feet 35 are preferably positioned between the lower axial end 14 of the air-core choke coil 2, in particular its lower winding star 15, and the upper support plane 32 of the annular support body 10.

[0079] The support feet 35 can be designed to be more elastically compliant in the vertical direction or to have lower vertical stiffness compared to the vertical elasticity or stiffness of the annular support body 10. The vertical elasticity of the support feet 35 can be achieved by implementing metallic spring arms 36 and/or disc springs. It may also be advantageous if the support feet 35 provide a predetermined elasticity acting in the horizontal direction between the air-core choke coil 2 and the annular support body 10.

[0080] It may be advantageous if the support feet 35 are firmly connected to the annular support body 10 by means of several concrete anchoring elements 37 (indicated by dashed lines), in particular by means of so-called concrete anchoring screws, which are anchored or can be anchored in the concrete 18 of the annular support body 10, at positions that are not predetermined, in particular at arbitrary positions along the circumference 31 of the annular support body 10. The concrete anchoring elements 37 can be screwed or drilled and/or glued directly into the concrete 18 of the annular support body 10. This allows for relatively universal use of the annular support body 10 for various embodiments of air-core choke coils 2. In particular, this makes the spacing or number of support feet 35 on the underside of the air-core choke coil 2 independent of fixed, predetermined attachment points on the upper support plane 32 of the annular support body 10. Furthermore, this allows for improved compensation of dimensional tolerances with respect to the air-core choke coil 2 and/or the annular support body 10. The corresponding concrete anchoring elements 37 can be positioned relatively flexibly by drilling into the concrete 18 of the annular support body 10 at the locations determined by the spacing of the support feet 35 and/or by any positional or dimensional tolerances. This also improves ease of assembly and installation.

[0081] Metallic coupling brackets 39 can be formed between the upper ends 38 of the column-like insulators 11 and the annular support body 10. These coupling brackets 39 are designed for the mechanical, load-bearing connection between the upper ends 38 of the column-like insulators 11, in particular their head fittings, and preferably the lower support level 33 of the annular support body 10. This connection can be made via a plurality of screw- or bolt-like connecting elements 40. Alternatively, it is also conceivable to support or attach the coupling brackets 39 to the outer surface of the annular support body 10, which, however, would result in higher shear stresses between the coupling brackets 39 and the annular support body 10, particularly with regard to screw- or bolt-like connecting elements, for example in the form of concrete anchoring elements.

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[0082] As further illustrated in Fig. 5, independently of or in combination with the measures described further, the annular support body 10 can be provided with an electrically conductive polarity conductor 41, for example made of aluminum, copper, or iron or stainless steel. This polarity conductor 41 can be in the form of a strip or cable. It is advantageous if the polarity conductor 41 is at least partially or completely cast into the concrete 18 of the annular support body 10 and is thereby connected to the annular support body 10 in a tear-resistant manner and well protected against mechanical stress.

[0083] As further illustrated by way of example in Fig. 5, the individual metallic coupling brackets 39 can be connected in series by means of the electrically conductive polarity conductor 41. In particular, it can be advantageous if the polarity conductor 41 electrically connects all coupling brackets 39 to one another by electrically coupling anchoring elements (indicated by dashed lines) cast into the concrete 18, which are provided for mechanical and electrical connection with the coupling brackets 39. The anchoring elements cast into the concrete 18 can have threaded bushings for mechanical and simultaneously electrical connection with the metallic coupling brackets 39 to the column-like insulators 11. This connection can be made via a plurality of screw- or bolt-like connecting elements 40 between the anchoring elements cast into the concrete 18 and the respective coupling brackets 39. In particular, it can be provided that the coupling brackets 39, when in their installed state, are in mandatory electrical contact with the polarity conductor 41.

[0084] The polarity conductor 41 does not form a closed ring structure, but extends only over a partial section of the ring circumference 31 of the annular support body 10, as can be seen in Fig. 5 by means of an interrupted section 42 of the polarity conductor 41. In order to bring all metallic coupling brackets 39 to a defined electrical voltage potential, it can be provided that the polarity conductor 41 or at least one of the coupling brackets 39 is electrically connected to the air-core choke coil 2, for example to its lower winding star 15, by means of at least one electrical connecting bridge 43, 43', as is schematically shown in the left section of Fig. 5. The at least one electrical connecting bridge 43, 43' can be designed as a ribbon- or rope-shaped conductor, which can extend predominantly in the axial direction of the annular support body 10.

[0085] Figures 6 and 7 show further and, if applicable, independent embodiments of the annular support body 10, using the same reference numerals or component designations for identical parts as in the preceding figures. To avoid unnecessary repetition, reference is made to the detailed description in the preceding figures. Here, the concrete body 18 of the annular support body 10 is tapered or reduced along its ring circumference 31 with respect to its cross-section, in particular with respect to its cross-sectional area, along mutually spaced partial sections 44, i.e., it is narrowed section by section and then widened again. This allows the volume of concrete 18 for the annular support body 10 to be reduced without significantly impairing its static or mechanical properties. In particular, this allows an improved ratio between mass and static parameters of the annular support body 10 to be achieved.

[0086] Cross-sectionally enlarged sections 45 between the successive, tapered sections 44 along the ring circumference 31 can function as support zones 46 of the annular support body 10 against the column-like insulators 11. By way of example, six cross-sectionally enlarged sections 45 are provided in each of Figures 6 and 7, although the number of these sections can also be lower or higher, in particular between three and twelve. In the embodiment according to Figure 6, a support zone 46 is formed against a column-like insulator 11 in each of the enlarged sections 45, so that, for example, six column-like insulators 11 are provided. In the embodiment according to Figure 7, on the other hand, a support zone 46 is formed against a column-like insulator 11 in every second enlarged section 45, so that, for example, three column-like insulators are provided.

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11 are planned.

[0087] In the embodiment according to Fig. 6, the annular support body 10 has a first cross-sectional height 47 and at least a second cross-sectional height 48 along its ring circumference 31, wherein the at least one second cross-sectional height 48 is comparatively larger and thus defines an extended section 45. Preferably, the upper support plane 32 for the air-core choke coil 2 (Fig. 5) is continuously variable or flat. The support zones 46 opposite the column-like insulators 11 can define the lower support plane 33 of the annular support body 10 or lie parallel to the lower support plane 33.

[0088] According to the embodiment shown in Fig. 7, the annular support body 10 has a first cross-sectional width 49 and at least one second cross-sectional width 50 along its ring circumference 31. These cross-sectional widths 49 and 50 are dimensioned radially to the annular support body 10, with the at least one second cross-sectional width 50 being comparatively larger and thus defining an extended section 45. Preferably, the upper support plane 32 for the air-core choke coil 2 (Fig. 5) is continuously variable or flat.

[0089] In particular, in the embodiment according to Fig. 7, the air-core choke coil 2 can be positioned on the annular support body 10 such that at least some of its electrically parallel-connected winding layers, or the entire electrical winding 51, overlap or intersect the annular support body 10 in a top view (bird's-eye view) such that the laterally or radially tapered sections 44 of the annular support body 10 define vertically extending cooling air openings or cooling air channels 52 for the electrical winding 51 of the air-core choke coil 2. In particular, this allows the lower axial end of the air-core choke coil 2 to be at least partially exposed and facilitates the supply of convective cooling air to the lower axial end 14 or into the electrical winding 51 of the air-core choke coil 2.

[0090] In the embodiment according to Fig. 8, a further and optionally independent embodiment of the ring-shaped support body 10 is shown, wherein the same reference numerals or component designations are used for identical parts as in the preceding figures. To avoid unnecessary repetition, reference is made to the detailed description in the preceding figures.

[0091] The annular support body 10 has a polygonal shape with respect to its ring circumference 31, which is, for example, hexagonal. In particular, the outer and/or inner outline shape of the annular support body 10 can be square to sixty-four-sided, and especially hexagonal to dodecagonal.

[0092] Regardless of the outline shape of the annular support body 10, it can have several cooling air channels 52 extending between its underside and its top side, preferably evenly distributed around the circumference 31, which are provided for the passage of cooling air. These cooling air channels in the concrete 18 of the annular support body 10 can run vertically or be inclined relative to the vertical.

[0093] Likewise, regardless of the outline shape of the annular support body 10 made of concrete 18, the axial height 53 between its upper support level 32 made of concrete 18 and its lower support level 33 made of concrete 18 can be between 20 cm and 100 cm, preferably between 30 cm and 70 cm. In the embodiment according to Fig. 6, the axial height 53 of the annular support body 10 would correspond to the second or larger cross-sectional height 48 described above.

[0094] The exemplary embodiments show possible embodiment variants, whereby it should be noted at this point that the invention is not limited to the specifically illustrated embodiment variants thereof, but rather various combinations of the individual embodiment variants are also possible and this possibility of variation lies within the skill of the person skilled in this technical field due to the teaching on technical action by the present invention.

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[0095] The scope of protection is defined by the claims. However, the description and the drawings are to be used to interpret the claims. Individual features or combinations of features from the different embodiments shown and described can in themselves represent independent inventive solutions. The problem underlying the independent inventive solutions can be found in the description.

[0096] All references to value ranges in the present description are to be understood as including any and all sub-ranges thereof, e.g. the reference 1 to 10 is to be understood as including all sub-ranges starting from the lower limit 1 and the upper limit 10, i.e. all sub-ranges begin with a lower limit of 1 or greater and end at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0097] For the sake of clarity, it should be noted that for better understanding of the structure, some elements have been shown not to scale and/or enlarged and/or reduced in size.

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REFERENCE MARK LIST

1 coil assembly unit 31 ring circumference

2 Air core choke coil 32 upper support level

3 Coil axis 33 lower support level

4 Diameter 34 Chamfer

5 air cores, 35 support feet

6 outer diameters, 36 metallic spring arms

7 Supporting structure 37 Concrete anchoring elements 8 Ground level 38 Upper ends

9 support height 39 coupling brackets

10 ring-shaped support bodies, 40 connecting elements, 11 column-like insulators, 41 polarity conductors

12 Support leg 42 Interruption section 13 Support bracket 43, 43° Connecting bridge

14 lower axial end 44 tapered sections 15 lower winding star 45 widened sections 16 upper winding star 46 support zones

17 upper axial end 47 first cross-sectional height 18 concrete 48 second cross-sectional height 19 reinforcement 49 first cross-sectional width 20 bars 50 second cross-sectional width 21 mats 51 electrical winding

22 surface profiling 52 cooling air channels

23 overlap sections, 53 axial installation height

24 Reinforcement ring element 25 Central annular space

26 first support body part

27 additional support body parts

28 joining levels

29 Ring axle

30 inner cavity

Claims (24)

x bes AT 528 483 A2 2026-01-15 Ss N patent claims 1. Coil assembly (1) for electrical power supply networks, the coil assembly (1) comprising a hollow cylindrical air-core choke coil (2) with a vertically extending coil axis (3), and a support structure (7) with an annular support body (10), which annular support body (10) defines an upper support plane (32), and which annular support body (10) is arranged below a lower axial end (14) of the air-core choke coil (2) and is designed for load-bearing support of the air-core choke coil (2), which support structure (7) further comprises a plurality of column-like insulators (11), which column-like insulators (11) are designed for electrically insulating and load-bearing support of the annular support body (10) and the air-core choke coil (2) against a ground foundation or against a ground level (8), characterized in that the annular support body (10) Concrete (18) which concrete (18) is used as material to provide the load-bearing, strength-relevant ring shape of the supporting body (10), wherein the concrete (18) contains a non-ferromagnetic reinforcement (19), and wherein this non-ferromagnetic reinforcement (19) comprises fibers and/or rods (20) and/or mats (21) made of at least one non-ferromagnetic material embedded in the concrete (18). 2. Coil assembly unit according to claim 1, characterized in that the at least one non-ferromagnetic material is formed by a plastic material and/or by a glass fiber material and/or by a carbon material and/or by a textile material. 3. Coil assembly according to claim 1 or 2, characterized in that the at least one non-ferromagnetic material is formed by stainless steel or corrosion-resistant steel. 4. Coil assembly unit according to claim 3, characterized in that the stainless steel or stainless steel is formed in the form of rods (20) and/or mats (21). 5. Coil assembly unit according to one of the preceding claims, characterized in that the rods (20) and/or mats (21) have a surface profile (22) which surface profile (22) is designed to create a positive connection with the concrete (18) enclosing the rods (20) and/or mats (21). 6. Coil assembly unit according to one of the preceding claims, characterized in that the rods (20) and/or mats (21) extend along the ring circumference (31) of the annular support body (10), but do not form a closed electrical loop. 7. Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) is formed in one piece, in particular from molded concrete (18). 8. Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) is enclosed in relation to its ring circumference (31) and has a central annular space (25). 9. Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) has at least one inner cavity (30), in particular at least one cavity (30) extending over the ring circumference (31), or cavities (30) extending over sections of the ring circumference (31). 10. Coil assembly unit according to one of the preceding claims, characterized in that the upper support plane (32) of the annular support body (10) is formed flat- 18 / 28 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. AT 528 483 A2 2026-01-15 det is and/or that the ring-shaped support body (10) has a flat lower support plane (33). Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) is tapered along its ring circumference (31) with respect to its cross-section in partial sections (44). Coil assembly unit according to claim 11, characterized in that the annular support body (10) has a first cross-sectional height (47) and at least a second cross-sectional height (48) along its ring circumference (31), and preferably the upper support plane (32) for the air core choke coil (2) is continuously designed. Coil assembly unit according to claim 11 or 12, characterized in that the annular support body (10) has a first cross-sectional width (49) and at least a second cross-sectional width (50) along its ring circumference (31), and preferably the upper support plane (32) for the air core choke coil (2) is continuously designed. Coil assembly unit according to one of the preceding claims, characterized in that upper ends (38) of the column-like insulators (11) are connected, in particular screwed, to a lower support plane (33) of the annular support body (10). Coil assembly unit according to one of the preceding claims, characterized in that several spaced-apart support feet (35) at the lower axial end (14) of the air core choke coil (2) are connected, in particular screwed, to the upper support plane (32) of the annular support body (10). Coil assembly unit according to claim 15, characterized in that the support feet (35) between the air core choke coil (2) and the annular support body (10) are designed to be more elastically flexible in the vertical direction or with lower vertical stiffness compared to the vertical elasticity or stiffness of the annular support body (10). Coil assembly unit according to claim 15 or 16, characterized in that the support feet (35) are firmly connected to the annular support body (10) at positions along the ring circumference (31) of the annular support body (10) by means of concrete anchoring elements (37) which are anchored or can be anchored in the concrete (18) of the annular support body (10) at positions not predetermined locally along the ring circumference (31) of the annular support body (10). Coil assembly unit according to one of the preceding claims, characterized in that metallic coupling brackets (39) are formed between the upper ends (38) of the column-like insulators and the annular support body (10), which coupling brackets (39) are provided for the mechanical, load-transmitting connection between the upper ends (38) of the column-like insulators (11) and preferably the lower support plane (33) of the annular support body (10). Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) comprises an electrically conductive polarity conductor (41), which polarity conductor (41) is at least partially cast into the concrete (18) of the annular support body (10). Coil assembly unit according to claims 18 and 19, characterized in that the individual metallic coupling consoles (39) are connected in series by means of the electrically conductive polarity conductor (41), wherein, however, the polarity conductor (41) does not form a closed ring structure, but only extends over a partial section of the ring circumference (31) of the annular support body (10). Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) has a polygonal shape with respect to its ring circumference (31), in particular is formed at least square to sixty-four-sided. Coil assembly unit according to one of claims 1 to 6 and 8 to 21, characterized in that the annular support body (10) is formed in multiple parts, wherein the at least 19 / 28 a joining plane (28) between joinable support body parts (26, 27) runs radially to a ring axis (29) of the ring-shaped support body (10). 23. Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) has several cooling air channels (52) arranged distributed over the ring circumference (31) in its ring body, extending between its underside and its top side, which are provided for the passage of cooling air. 24. Coil assembly unit according to one of the preceding claims, characterized in that the annular support body (10) comprising concrete (18) has an axial height (53) which, measured between its upper support level (32) made of concrete (18) and a lower support level (33) made of concrete (18), is between 20 cm and 100 cm, preferably between 30 cm and 70 cm. This includes 8 sheets of drawings.