WO2010003599A2

WO2010003599A2 - Device and method for servicing an ocean current power station

Info

Publication number: WO2010003599A2
Application number: PCT/EP2009/004843
Authority: WO
Inventors: Matthias Grassow; Michael Hölle; Bernd Joos; Michael Engelhardt
Original assignee: Voith Patent Gmbh
Priority date: 2008-07-11
Filing date: 2009-07-06
Publication date: 2010-01-14
Also published as: WO2010003599A3; DE102008032626A1

Abstract

The invention relates to an ocean current power station comprising a submersible turbine/generator unit (3). At least part of the pneumatic and/or hydraulic components used for operating the turbine/generator unit is housed in a supply unit (1) that can be separately lifted.

Description

Apparatus and method for servicing a sea current power plant

The invention relates to a method and a device for the maintenance of a sea current power plant, in particular a tidal power plant with a diving, in the ambient flow freestanding turbine generator unit.

Ocean current power plants that are used without dam structures free in a driving flow, in particular a tidal current, are known. A problem of these plants is the execution of maintenance and service work. Thus, for ocean current power plants due to the corrosion by the salt water and due to the abrasive effect of transported with the flow of water sediment load is a constant burden on the system. In addition, there is the fouling problem, since such plants are populated by maritime organisms after a short time. Further, a

Plant service due to the difficult accessibility consuming. Attempts are made to avoid the use of service divers as much as possible, so that in most cases a lifting of the system above the water level to perform repairs is inevitable.

The lifting of ocean current power plants is difficult due to their size and the resulting heavy weight. Furthermore, there is usually only a limited time window available for such a rescue action, since in the sea areas suitable for the installation of such installations, typically only for a short time, sufficiently low

Water flow velocities are present, which allow safe recovery and reinstallation of the plant.

A known measure to simplify a plant service is the outgoing from the ocean current power electrical

Connect power cable using an ocean-compatible plug with an ocean cable. Reference is made by way of example to GB 2 256 011 A, which is a

BESTATIGUNGSKOPIE anchored turbine generator unit describes which discloses a releasable electrical coupling of the electric power cable in the region of the anchor point. Thus, the turbine-generator unit can be brought aboard a ship and removed for repair purposes by a separation from the ocean cable from the installation site. To connect the electric power cable from the ocean current power plant, either the ocean cable must be raised or an oceanworthy underwater plug must be used, which in most cases will be manually coupled by a service diver. This is costly and time consuming, in addition to the risk to the diver of underwater work at great depths.

The invention has for its object to provide an apparatus and a method that simplifies the service and installation of an underwater power plant. Regular plant inspection and regular maintenance should be possible. Furthermore, to carry out the maintenance work no specially designed salvage ship should be necessary and instead use a small-scale watercraft use.

The object underlying the invention is solved by the features of the independent claim. Advantageous embodiments emerge from the subclaims.

To simplify the maintenance of a sea current power plant, the inventors have recognized that part of the pneumatic and / or hydraulic components necessary for plant operation can be accommodated in a separately liftable supply unit. These so summarized and can be brought by means of the supply unit regardless of the other parts of the system to the water surface components are easy to maintain. In this case, those pneumatic and / or hydraulic components of the system are preferably accommodated in the supply unit, which represent a certain risk of failure and are therefore subject to regular maintenance. Particularly preferred is an embodiment for the only safety-relevant or for an emergency operation necessary pneumatic and / or hydraulic components are permanently installed in the turbine generator unit and all other components are included in the supply unit.

For further development, electrical components are also integrated into the supply unit and can thus be regularly maintained. This concerns an electrical connection device for making a detachable connection between the electric power cable emanating from the ocean current power plant and an ocean cable. Both the electric power cable and the ocean cable end accordingly in the supply unit and can be interconnected depending on the type of encapsulation of the supply unit. Seawater-suitable and wet-plug connectors are particularly advantageous, even in the event that the supply unit itself is encapsulated watertight.

The pneumatic components that are considered for inclusion in the supply unit, are a compressed air reservoir and / or a pneumatic pressure adjustment and / or a pneumatic valve assembly and / or a pneumatic pressure control. Suitable hydraulic components for

The supply unit includes filters and cleaning systems for the hydraulic medium. In the event that water circulates in the hydraulic circuit, the ambient water inlet is advantageously integrated into the supply unit and, in addition, a cyclone filter is received for cleaning ambient water. Furthermore, pumps, working fluid accumulators, pressure accumulators, pressure regulators and valve arrangements for the hydraulics can be placed in the supply unit.

The supply unit is connected by means of at least one supply line with the parts remaining at the installation service parts of the turbine generator unit. These remaining on-site components of the underwater power plant are in particular the water turbine, the mechanical Components of the powertrain and the components of the electric generator, as far as they do not affect the control and power electronics. Accordingly, according to the invention all large and heavy components of the ocean current power plant remain in the installed state, while the components used in standard operation for measurement, control and regulation tasks and media management, as far as they are not emergency systems, can be raised separately. It is conceivable to provide a plurality of supply units that are independent of each other manageable. Accordingly, the pneumatic, the hydraulic and the electrical or electronic components can each be combined separately. However, it is particularly preferred to use only a supply unit, which is enveloped by a liquid-tight final housing for ease of handling.

For a first embodiment of the invention, the supply unit is in

Normal operation connected to the turbine-generator unit or the support structure of the ocean current power plant and can be recovered in case of service. It is conceivable that the supply unit is automatically unlocked and is raised by an associated buoyancy system to the surface. The system unit forming the supply unit is to be constantly connected via at least one supply line with the permanent part of the system, wherein in the supply line, the electrical, pneumatic and hydraulic connection lines are added.

As to raise the supply unit to the water level the

Supply line must have a sufficient length to constantly maintain the connection between the supply unit and the turbine generator unit of the ocean current power plant, should be provided for a arranged in the region of the ocean current power plant during normal operation supply unit a cable management system. Such makes it possible to safely keep the supply line from the circle of the water turbine. One conceivable design is a cable winder or an am Seabed filed rigid guide element, which spaces the supply line from the turbine-generator unit. Corresponding measures are to be taken if in addition the ocean cable leads into the supply unit.

For a further embodiment of the invention, a maintenance of the supply unit to a separation of the connecting cable to the turbine generator unit or a decoupling of plugs, which are assigned to the connecting cable made. If wet couplers and guide systems are used for automatic coupling, reinstallation may be performed without the use of service divers when returning the supply unit after the installation service has been performed.

For a second, preferred embodiment alternative, the supply unit is arranged at a distance from the turbine generator unit. This spatial separation simplifies the problem of developing the

Supply line into the moving parts of the ocean current power plant. Typically, for a turbine-generator unit, which rests on a foundation structure based on the seabed, the supply line is guided in the normal operating state via the seabed to a remote supply unit. This can be raised by a simple crane system of a watercraft used for the service such that at a sufficient length of the supply line this even at a shallow angle to the ocean current power plant runs when the supply unit is on board the service ship. As a result, the backup of supply lines is simplified and it can be dispensed with a separate cable management.

The housing of the supply unit is preferably designed so that it forms at least one mechanical protection, for example against stone chipping, for the components accommodated therein. Preferred is a variant of a protective housing, which leads to a watertight sealed interior of the supply unit. Furthermore, for a preferred embodiment of the invention, the supply unit is provided with devices which facilitate lifting. On the one hand, this relates to automatic coupling devices for attaching a lifting device of a crane system. For a design alternative, the supply unit is designed as a self-propelled system that can be triggered by remote control. It is also conceivable that only a rope or chain system used for salvage, triggered by a radio signal or an acoustic signal, be led to the water surface. For this purpose, for example, one end of a cable connected to the supply unit or a chain can be provided with a buoy whose ballasting can be triggered remotely. Furthermore, it is conceivable to equip the supply unit with a transmitter in order to simplify their location.

The invention will be explained in more detail below on the basis of preferred exemplary embodiments and in conjunction with illustration representations. These details show:

FIG. 1 schematically shows in simplified form a sea current power plant with a supply unit according to the invention in the raised state.

FIG. 2 shows the supply unit from FIG. 2 at the installation site on the riverbed.

FIG. 3 shows a design alternative for which the supply unit is accommodated in the turbine generator unit of the ocean current power plant.

FIG. 4 shows a supply unit from FIG. 3 which has been guided to the water surface. FIG. 5 shows, for one embodiment of the invention, the division of pneumatic components onto a supply unit and the parts of the turbine generator unit remaining at the installation location.

FIG. 6 shows, for one embodiment of the invention, the division of hydraulic components onto a supply unit and the parts of the turbine generator unit remaining at the installation location.

FIG. 1 shows a schematic simplified perspective view of the basic components of a sea current power plant 2 according to the invention. This comprises a turbine generator unit 3 with a water turbine 4 and a machine nacelle 5, which is mounted on a support structure 8. For the present embodiment, the support structure 8 is fundamental and supports the turbine generator unit 3 against the water bottom 31 from. An alternative embodiment with a floating support structure 8 is conceivable.

According to the invention, a part of the system components used for the operation of the turbine generator unit 3 is accommodated in a separately liftable supply unit 1. For the embodiment shown in Figure 2, this is spatially spaced in the operating position to the other parts of the

Turbine generator unit 3 deposited at the bottom of the river and connected to these via a supply line 6. For the exemplary embodiment illustrated in FIGS. 1 and 2, the supply line is guided from the machine nacelle 5 to the body of water 31 by means of a pivotable arm 30, which is articulated on the support structure 8. In this case, a storage of the supply line 6 takes place on the side facing away from the water turbine 4 side of the ocean current power plant 2. For an embodiment with an azimuth rotator for the turbine generator unit 3 (such is not shown in detail in the figures) are more devices for safe Leadership of the supply line 6 conceivable that both a twisting of the

Supply line 6 at a rotation of the machine nacelle 5 and also prevents entanglement in the rotating machine part. This comes In particular, an azimuth rotating mechanism in question, which moves the machine nacelle between two 180 ° spaced operating positions and back. The supply line 6 is then guided by means of an associated cable management always leeward to the water turbine 4.

The length of the supply line 6 is selected so that the supply unit 1 can be lifted separately, without the parts of the turbine generator unit 3 remaining at the installation site having to be raised synchronously. This is outlined in FIG. In addition, the supply line is preferably so long enough that it does not get into the circle of the water turbine 3. In addition to the length of the supply line 6, the storage location of the supply unit is selected on the leeward side for the ocean current power plant for this purpose. In the event that the ocean current power plant uses a flow with alternating direction of flow for energy production, for a preferred embodiment of the maintenance method according to the invention the

Supply unit 1 of a watercraft 26 is only raised when a winding of the supply line 6 in the rotating parts of the turbine generator unit 3 can be safely excluded.

For the separate lifting of the supply unit 1 are different

Process conceivable. Preference is given to an automatic process, so that, for an advantageous embodiment of the supply unit, a remotely controllable buoyancy mechanism 9 is associated, which allows a fernausgelöstes Auftreiben. Alternatively, a rope or chain connection can be automatically brought to the water surface, so that by a second subsequent

Process step by means of a suitable crane system 27, the supply unit 1 is raised to the water surface. It is also possible to provide the crane system 27 on board the watercraft 26 used for salvage with a coupling device 29, which allows automatic docking to the supply unit 1 at the installation site. Furthermore, the storage of the supply unit 1 takes place in a predetermined relative position to the turbine generator unit 3 by means of a suitable foundation. This can be a gravity foundation or pile foundation. Alternatively, an uncontrolled carry over by the flow of water is prevented by means of an anchor.

In Figures 3 and 4, a design alternative of the invention is shown. For this purpose, the supply unit 1 is received in the turbine generator unit 3 during operation of the flow power plant 2. To carry out maintenance, the supply unit 1 is led to the water surface. For the embodiment sketched in FIG. 4, a remotely controllable buoyancy mechanism 9 is assigned to the supply unit 1. If this is triggered, a supply unit 1 decoupled from the rest of the turbine generator unit 3 can be led to or in the vicinity of the water level. From there, a simple reception of the supply unit 1 on board a watercraft 26 is possible.

FIG. 4 shows that, even in the event of decoupling of the supply unit 1 from the turbine generator unit 3, a connection between these two system components is still provided via the supply line 6. This must have a suitable length for driving on the water level. Furthermore, a device in the turbine generator unit 3 for handling the supply line 6 is preferably provided. In the simplest case, this is a system that the supply unit 6 catches up with the installation of the supply unit 1.

In the event that is dispensed with the constantly existing connection between the supply unit 1 and the turbine-generator unit 3, suitable coupling devices between the terminals of the supply unit 1 and the turbine-generator unit 3 are provided which allow automatic docking. Furthermore, the supply unit 1 or an installation system provided for this purpose can be equipped with a guide cable structure in order to secure the installation of the supply unit 1 Supply to a receiving opening in the turbine-generator unit 3 to accomplish.

The supply unit 1 comprises at least part of the pneumatic and / or hydraulic components used for the operation of the turbine generator unit 3. For a preferred refinement, electrical components are additionally accommodated in the supply unit 1. This includes a not shown in detail coupling device for connecting the outgoing from the ocean current power plant 2 electric power cable to an ocean cable 7 a. Further components suitable for the encapsulation in the supply unit 1 are control and regulating devices, power electronic components and frequency converters as well as components of a DC intermediate circuit or electrical energy storage.

With reference to FIG. 5, the distribution of pneumatic components to the supply unit 1 for one and to the parts of the turbine generator unit 3 remaining stationary at the installation location can be shown for an exemplary embodiment. To illustrate this separation, a dashed line 10 is shown in FIG. Recorded in the supply unit 1 is a compressed air reservoir 12, for example in the form of compressed gas cylinders. This is in pneumatic communication with a pneumatic shut-off valve 13 and a pneumatic valve 14.1, followed by a pneumatic pressure-holding valve 15.1. These pneumatic components listed above are connected via the supply line 6.1 with the pneumatic components remaining at the installation site. These are either safety-relevant and for an emergency operation indispensable pneumatic components or it is such components that are to be arranged in the immediate structural proximity of the mechanical structures of the turbine generator unit 3. Specifically, a reserve reservoir 16, a pneumatic pressure-retaining valve 15. 2 remain stationary and

Control of a brake piston 17, the pneumatic valves 14.2 and 14.3. there is provided in the closing direction of the brake piston 17 of the reserve memory 16 used for emergency operation.

FIG. 6 shows the distribution for an exemplary embodiment in the case of hydraulic components. Again shown is a dividing line 10 between those components which are assigned to the supply unit 1 and those components which remain stationary at the installation location of the turbine generator unit 3. Furthermore, it is assumed for the exemplary embodiment illustrated by a water-based hydraulics, the treated ambient water and used as a lubricant for the storage of

Meeresströmkraftwerks 2 and used to operate a cooling circuit 24. In this case, the cooling circuit 24 can be used for cooling the electric generator or the bearing components.

In the supply unit 1, a pre-filter 18 is added, which adjoins an ambient water inlet, not shown in detail. Subsequently, a feed pump 19.2 is arranged, which feeds the prefiltered water to a cyclone filter 20, which loads a working fluid accumulator 21. From the working fluid accumulator 21 scoop the feed pumps 19.2 and 19.3, which are provided for the supply of lubricant to the bearings. Another feed pump 19.4 passes treated water into the refrigeration cycle 24.

Specifically follows after the feed pump 19.2, a hydraulic pressure holding valve 23.1, followed by the supply line 6.2, which leads from the supply unit 1, starting to the stationary remaining components of the turbine generator unit 3. These are a throttle valve arrangement for the first axial bearing 25.1 and a throttle valve arrangement for the first radial bearing 25.2. Accordingly, the other camps are supplied. For this purpose, starting from the feed pump 19.3, a hydraulic pressure-maintaining valve 23.2 is used, followed by the supply line 6.3 up to the components of the second hydraulic branch remaining at the installation location. These are a throttle valve arrangement for the second radial bearing 25.3 and a throttle valve arrangement for the second thrust bearing 25.4. The hydraulic branch for the cooling circuit 24, which itself remains at the installation site, is supplied via the supply line 6.4 by the components integrated in the supply unit 1, namely a feed pump 19.4, a volume flow measuring device 22 and a hydraulic throttle valve 25.

Further embodiments of the invention are conceivable. In this case, measuring instruments used in particular for plant development can be included in the supply unit 1 for testing a sea stream plant serving as a prototype, whereby a simple conversion and reconfiguration of both the plant components and the components provided for the test and monitoring is possible due to the separate lifting capability of the supply unit is.

LIST OF REFERENCE NUMBERS

1 supply unit

2 ocean current power plant 3 turbine generator unit

4 water turbine

5 Nacelle 6, 6.1, 6.2, 6.3, 6.4 Supply line 7 Ocean cable 8 Support structure

9 remotely controllable buoyancy mechanism

10 dividing line

12 compressed air storage

13 pneumatic shut-off valve 14.1, 14.2, 14.3 pneumatic valve

15.1, 15.2 pneumatic pressure relief valve

16 reserve memory

17 brake pistons

18 Pre-filter 19.1, 19.2, 19.3, 19.4 Feed pump

20 cyclone filter

21 working fluid storage

22 Volume flow measuring device 23.1, 23.2 Hydraulic pressure holding valve 24 Cooling circuit

25 hydraulic throttle valve

25.1 throttle valve arrangement for the first thrust bearing

25.2 Throttling valve arrangement for the first radial bearing

25.3 Throttling valve arrangement for the second radial bearing 25.4 Throttling valve arrangement for the second axial bearing

26 watercraft

27 crane system 28 Gravity foundation

29 coupling device

30 swiveling boom

31 body of water

Claims

claims

1. Ocean current power plant with a submerged turbine generator unit

(3), characterized in that at least a part of the pneumatic and / or hydraulic components used for the operation of the turbine generator unit is accommodated in a supply unit (1) which is separable from the other components of the turbine generator unit for maintenance can be lifted separately.

2. Meeresströmkraftwerk according to claim 1, characterized in that the supply unit (1) via at least one supply line (6) with the turbine generator unit (3) is connected, that the connection when lifting the supply unit (1) remains above the water level ,

3. ocean current power plant according to one of claims 1 or 2, characterized in that the supply unit (1) in normal operation spatially spaced from the turbine-generator unit (3) is arranged.

4. ocean current power plant according to one of claims 1 to 3, characterized in that in the supply unit (1) accommodated pneumatic components comprises a compressed air reservoir (12) and / or a pneumatic pressure adjusting device and / or a pneumatic valve assembly and / or a pneumatic pressure control.

5. ocean current power plant according to one of the preceding claims, characterized in that in the supply unit (1) accommodated hydraulic components an ambient water inlet and / or a cyclone filter (20) for cleaning

Ambient water and / or a pre-filter (18) and / or a feed pump (19.1 - 19.4) and / or a working fluid accumulator (21) and / or a pressure accumulator and / or a valve arrangement.

6. ocean current power plant according to one of the preceding claims, characterized in that in the supply unit (1) an electric

Connecting device for the connection of an outgoing from the ocean current power station electric power cable to an ocean cable (7) is housed.

7. ocean current power plant according to one of the preceding claims, characterized in that in the supply unit (1) electrical and electronic components of the plant control and / or the plant sensors are housed.

8. ocean current power plant according to one of the preceding claims, characterized in that the power electronics of the electric generator and / or a frequency converter and / or an electrical energy storage and / or components of a DC voltage intermediate circuit in the supply unit (1) are housed.

9. ocean current power plant according to one of the preceding claims, characterized in that the supply unit (1) is enclosed by a waterproof encapsulated protective housing.

10. ocean current power plant according to one of the preceding claims, characterized in that the supply unit (1) comprises a coupling device (28) for a lift of a crane system (27).

11. ocean current power plant according to one of the preceding claims, characterized in that the supply unit (1) comprises a remotely controllable buoyancy mechanism (9).

12. ocean current power plant according to one of the preceding claims, characterized in that the supply unit (1) has a transmitter for locating.

13. ocean current power plant, characterized in that the supply unit (1) comprises a chain and / or cable connection, which can be remotely controllable to the water surface.

14. Maintenance method for a sea current power plant with a diving turbine generator unit (3), characterized by the following method steps:

14.1 raising a supply unit (1) over the water level, in which at least a part of the pneumatic and / or hydraulic component used for the operation of the turbine generator unit (3) is arranged, wherein the remaining components of the turbine generator unit (3) at the installation site of the ocean current power plant (2) remain.

15. A maintenance method according to claim 14, characterized in that when raising the supply unit (1) via the water level, the supply unit (1) via at least one supply line is constantly connected to the remaining part of the turbine generator unit (3).