WATERPROOF UNDERWATER HOUSING FOR HOUSING HIGH-VOLTAGE COMPONENTS

Abstract

Waterproof underwater housing (1) for accommodating high-voltage components (14) having side surfaces (2) as well as a cover surface (3) and a bottom surface (4) and a waterproof feedthrough (7) for high-voltage lines (8), wherein the underwater housing (1) can be towed on the water surface with air-filled ballasting elements (13) and can be sunk by filling the ballasting elements (13).

Description

[0001] The invention relates to a waterproof underwater housing for accommodating high-voltage components, comprising side surfaces, a top surface and a bottom surface and a waterproof feedthrough for high-voltage lines.

[0002] The electrical output of offshore wind farms is in the range of many megawatts, sometimes several hundred megawatts. On offshore platforms, the electrical output is transformed to a high-voltage level of up to several hundred kilovolts and transmitted to land via high-voltage lines. The high-voltage lines run along or in the seabed. If the offshore wind farm is located many kilometers from land, correspondingly long high-voltage lines are necessary, making offshore reactive power compensation advantageous to compensate for the reactive power generated over the length of the high-voltage line. This requires additional offshore platforms on which high-voltage components for reactive power compensation are installed. Such offshore platforms are very costly to manufacture and maintain and can be disruptive to nature or shipping traffic.

[0003] The invention is based on the object of creating a cost-effective and environmentally friendly option for reactive power compensation of high-voltage lines of an offshore wind farm.

[0004] This object is achieved according to the invention with a waterproof underwater housing according to the features of claim 1 and an underwater housing system of the independent claim.

[0005] The further development of the invention can be found in the subclaims.

[0006] According to the invention, a watertight underwater housing for accommodating high-voltage components is provided, comprising side surfaces as well as a top surface and a bottom surface and a watertight feedthrough for high-voltage lines, wherein the underwater housing can be towed on the water surface with air-filled ballasting elements and can be sunk by filling the ballasting elements.

[0007] This advantageously allows the underwater housing with the high-voltage components, i.e., the entire reactive power compensation unit, to be manufactured cost-effectively onshore, for example, in a dry dock. The functions of the reactive power compensation unit are preferably tested onshore. The reactive power compensation unit can be towed out to sea by a ship, where it is connected to the high-voltage lines while floating on the water surface, or the high-voltage lines are connected to the high-voltage components. For this purpose, the connection areas of the high-voltage lines are raised to the water surface. The ballasting elements are then ballasted so that the underwater housing sinks to the seabed.The basic idea of ​​ballasting is also to allow maintenance work to be carried out when the underwater housing is in a floating position on the water surface.

[0008] While the ballasting elements can be filled with any high-density material, such as lead or gravel, which would then have to be removed to float the underwater housing, the preferred ballasting elements are ballast tanks, which are particularly suitable for filling with water. Pumps are provided inside the underwater housing to refloat it.

[0009] Although the underwater housing system does not require external power during normal operation, as the electrical energy is generated internally, for example by means of high-performance current transformers, an external power supply can also be provided, especially in the event that no current flows through the main cables.

[0010] A backup system, such as a connection for an emergency power supply and / or emergency telecommunications, can also be provided and routed to the surface via a line, such as a pipe. This line can be used to inject air into the ballasting elements if the pumps fail, or in designs where a pump is not included.

[0011] The ballasting elements or pumps are also needed to keep the underwater housing horizontal when sinking and surfacing (dynamic compensation by filling the tanks).

[0012] The underwater housing can be made from a variety of known materials, such as steel, aluminum alloys, or other metals. In a particularly practical embodiment, however, the side walls, the top surface, and / or the bottom surface are made of concrete. This allows for the production of a particularly cost-effective and seawater-resistant underwater housing. It goes without saying that the high-voltage components are inserted into the partially completed underwater housing before all surfaces of the underwater housing are sealed.

[0013] In a preferred embodiment, the deck surface of the preferably cubic underwater housing, when floating, is located at least 0.5 m, preferably at least 1 m, and more preferably at least 1.5 m above the water surface, as long as the ballasting elements are filled with air. This ensures that even in light sea conditions, the high-voltage lines can be connected in the area of ​​the deck surface without the influence of seawater.

[0014] The underwater housing preferably has a dry cable connection area, particularly above the deck surface, wherein the cable connection area is also sealed from the rest of the underwater housing. This ensures that the connection point of the high-voltage lines is located in an area protected from seawater and thus requires very little maintenance.

[0015] A preferred embodiment of the underwater housing features a resealable opening for personnel. This allows personnel to access the underwater housing for maintenance work without having to remove or open any surfaces of the housing. If the resealable opening is located above the water surface in air-filled ballasting elements, maintenance of the high-voltage components is possible offshore.

[0016] Preferably, the underwater housing has a protective frame to protect the cable connection area and / or the resealable opening. The risk of damage to the cable connection area or the resealable opening, as well as the risk of seawater ingress, is reduced.

[0017] In a preferred embodiment, the underwater housing has a payload of at least 10 tons, preferably at least 100 tons, and more preferably at least 300 tons. This allows the housing of correspondingly heavy high-voltage components.

[0018] The underwater housing system may preferentially be modular if practical weight constraints are exceeded or if separation should be required in the future due to conflicting functions. For example, if two separate cable connections to the platform are used, each would have its own underwater housing module, preventing emergencies, particularly faults, from spreading or allowing maintenance to be handled or performed independently. The same would apply to any redundant systems. In a modular underwater housing system, the modules could share the same larger base system to create space for multiple modules.

[0019] Furthermore, the invention provides an underwater housing system comprising a foundation element. This creates a support surface for the underwater housing and a secure base.

[0020] The foundation element is preferably at least predominantly embedded in the subsurface, with the foundation element more preferably having a bottom surface and side surfaces. This ensures particularly secure positioning of the underwater housing, which is at least partially protected from water currents. Furthermore, even in shallow waters, potential shipping traffic is not impeded if the underwater housing does not protrude, or only protrudes to a limited extent, from the seabed.

[0021] In a preferred embodiment, the underwater housing comprises a device for sealing against the foundation element. This effectively prevents the gap formed between the side surfaces of the foundation element and the underwater housing from being filled by sediment, which could impede the underwater housing from surfacing.

[0022] In a particularly practical embodiment, the underwater housing system comprises fastening means that are spaced from the foundation element by at least one underwater housing length and have at least one retaining line for securing the underwater housing. This ensures that by pulling the retaining line underneath, in particular by a pull line attached to the opposite end of the underwater housing, the freedom of movement of the underwater housing is restricted and positioning the underwater housing on the foundation element is simplified.Preferably, at least two fastening means spaced apart from one another, each with at least one holding line, are used, wherein the holding lines have points of engagement on the underwater housing spaced apart from one another, so that by placing the holding lines underneath and filling the ballasting elements, a particularly well-coordinated and controllable movement of the underwater housing towards the foundation element is enabled.

[0023] The drawings illustrate an embodiment of the invention. This is described in more detail below. The drawings show a schematic representation of an underwater housing and an underwater housing system.

[0024] The invention allows for various embodiments. To further clarify its basic principle, one of them is shown in the drawing and is described below. This shows in Fig. 1 shows a sectional view of an underwater housing; Fig. 2 shows a floating underwater housing connected to a high-voltage line; Fig. 3 shows a submerged underwater housing connected to a high-voltage line; Fig. 4 shows a plan view of a submerged underwater housing system.

[0025] Figure 1 shows a cubic and watertight underwater housing 1 with four side surfaces 2, a top surface 3, and a bottom surface 4. The side surfaces 2, the top surface 3, and the bottom surface 4 are made of concrete with low water permeability and cracking tendency. The concrete can be standard concrete or lightweight concrete.

[0026] The cover surface 3 has a resealable opening 5 for persons, which is shown in the open state. If the underwater housing 1 is floating, the resealable opening 5 can also be opened offshore. Furthermore, a dry cable connection area 6 is arranged on the cover surface 3 in such a way that it also encompasses the resealable opening 5. The cable connection area 6 receives a high-voltage cable 8 through a sealed feedthrough 7, which is led to a connection socket 9. The high-voltage cable 10 is already installed on land and sealed and led through the cover surface 3. The cable connection area 6 has a sealing flap 11 to the environment. A protective frame 12 is provided on both sides of the cable connection area 6 to protect the cable connection area 6.

[0027] A ballasting element 13 is arranged in each corner of the base of the cubic underwater housing 1. In this embodiment, it is designed as a ballast tank and can be filled with water or air via connecting elements (not shown). For a controllable floating or submerged position, the ballast tanks can be filled independently of one another. The high-voltage components 14 are arranged between the ballast tanks. A dehumidifier is installed in the underwater housing to adjust the humidity.

[0028] In Figure 2An underwater housing system 15 is shown with an underwater housing 1 floating on the water surface, which is already connected to the high-voltage lines 8 and mooring lines 16. The mooring lines 16 are kept under tension by introducing a force into the underwater housing 1 with tension lines 17. The mooring lines 16 are attached to the seabed by means of fastening means 18, as in Figure 4 After connecting the high-voltage line 8 in the cable connection area 6 and closing the opening 5 and the flap 11, the ballast tanks are filled with water so that the underwater housing 1 is positioned in a controlled manner in the foundation element 19 via the tension lines 17.

[0029] In Figure 3the positioning process of the underwater housing 1 in the foundation element 19 is complete. The underwater housing 1 is almost flush with the foundation element 19 in height. A device 20 for sealing the gap 21, which forms between the underwater housing 1 and the foundation element 19, seals the gap 21 so that deposits in the gap 21 are prevented. The foundation element 19 has a base plate 22 and side plates 23. The high-voltage line 8 is guided through a channel 25 in the seabed that can be closed by a cover 24. To insert the foundation element 19 into the seabed, a section of the seabed is excavated, and the area receiving the foundation element 18 is leveled and prepared with gravel. The foundation element 19 is then set, and the remaining recess is filled with gravel and covered with concrete.

[0030] According to an alternative (not shown), which is possible for cables with lower voltage levels or smaller diameters, the cables could also be laid in a spiral system, allowing vertical lifting. Such a vertical riser system can also be implemented to make a modular underwater housing system more compact.

[0031] Figure 4 shows a top view of the underwater housing system 15. A ship applies a force to one side of the underwater housing 1 by means of a towing line 17, thereby tensioning the holding lines 16 attached to the other side of the underwater housing 1, thereby aligning and positioning the underwater housing 1 relative to the foundation element 19. The high-voltage line 8 is routed to the underwater housing 1 perpendicular to the main longitudinal direction of the high-voltage line 8. LIST OF REFERENCE SYMBOLS 1 Underwater housing 16 tether 2 side surface 17 tow line 3 Cover area 18 Fasteners 4 Floor area 19 Foundation element 5 opening 20 device 6 Cable connection area 21 gap 7 Implementation 22 base plate 8 high-voltage line 23 Side panels 9 connection socket 24 Lid 10 High-voltage cables 25 channel 11 flap 12 protective frame 13 Ballasting element 14 High-voltage components 15 Underwater housing system

Claims

1. Waterproof underwater housing (1) for accommodating high-voltage components (14) having side surfaces (2) as well as a top surface (3) and a bottom surface (4) and a waterproof feedthrough (7) for high-voltage lines (8), characterized in that the underwater housing (1) with air-filled ballasting elements (13) can be towed on the water surface and can be sunk by filling the ballasting elements (13).

2. Waterproof underwater housing (1) according to claim 1, characterized in that the side surfaces (2), the top surface (3) and / or the bottom surface (4) have concrete and are preferably made of concrete.

3. Waterproof underwater housing (1) according to claim 1 or 2, characterized in that the cover surface (3) of the underwater housing (1), which is preferably cubic in basic shape, with air-filled ballasting elements (13) protrudes at least 0.5 m, preferably at least 1 m and more preferably at least 1.5 m from the water surface.

4. Waterproof underwater housing (1) according to at least one of the preceding claims, characterized in that the underwater housing (1) has a dry cable connection area (6), wherein the cable connection area (6) is sealed to the further underwater housing (1).

5. Waterproof underwater housing (1) according to at least one of the preceding claims, characterized in that the underwater housing (1) has a resealable opening (5) for persons.

6. Waterproof underwater housing (1) according to at least one of the preceding claims, characterized in that the underwater housing (1) has a protective frame (12) for protecting the cable connection area (6) and / or the resealable opening (5).

7. Waterproof underwater housing (1) according to at least one of the preceding claims, characterized in thatthe underwater housing (1) has a payload of at least 10 tons, preferably at least 100 tons and more preferably at least 300 tons.

8. Underwater housing system (15) with an underwater housing (1) according to at least one of the preceding claims, characterized in that the underwater housing system (15) has a foundation element (19).

9. Underwater housing system (15) with an underwater housing (1) according to claim 8, characterized in that the foundation element (19) is at least predominantly embedded in the subsoil, wherein the foundation element (19) preferably has a base plate (22) and side plates (23).

10. Underwater housing system (15) with an underwater housing (1) according to claim 8 or claim 9, characterized in that the underwater housing (1) has a device (20) for sealing to the foundation element (19).

11. Underwater housing system (15) with an underwater housing (1) according to one of claims 8 to 10, characterized in thatthe underwater housing system (15) has fastening means (18) which are spaced from the foundation element (19) by at least one underwater housing length and have at least one holding line (16) for fixing the underwater housing (1).