NO347108B1

NO347108B1 - Wave power generator system

Info

Publication number: NO347108B1
Application number: NO20211259A
Authority: NO
Inventors: Svein Tore Hollund
Original assignee: Hurricane Innovation As
Priority date: 2021-10-19
Filing date: 2021-10-19
Publication date: 2023-05-15
Also published as: NO20211259A1; WO2023068937A1

Description

WAVE POWER GENERATOR SYSTEM

Technical Field

The invention relates to a wave power generator system and a method for generating power using the wave power generator system.

More particularly, the invention relates to a wave power generator system that comprises a buoyancy arrangement for transferring the wave energy into power.

Background Art

Wave movements in the sea and in large inland lakes constitute a potential source of energy. Although there have been a lot of different suggestions for generator aggregates utilizing these renewable energy sources for powering the generator the amount of energy produced in this way is limited. The main reasons for that are economical. It is problematic to achieve aggregates of this kind that are economically competitive. Normally the power output from these aggregates is very small. Therefore, a large number of such aggregates are required to attain power of a significant level that can compete with conventional energy sources.

The challenge to achieve an economical competitive energy generating system based on these renewable energy sources is on one hand to provide efficient generator aggregates at low costs and on the other hand to provide an optimized system that can include a large number of such generator aggregates. The latter aspect is the crucial one for producing and supplying energy on a large commercial scale for the supply of the electric energy to an electric network.

Prior art publication WO2011096816 shows a platform with floating devices that moves vertically to generate, each of the floating devices is coupled to a generator to generate power.

FR475834, CN203756429, ITTO20111060, EP2679802, WO2009056854, CN108561265, WO2017086693 illustrates further examples of prior art of the wave power generator systems.

None of the prior art however discloses a wave power generator system that provides an optimal system for transferring the forces into power.

The system is beneficial in operational state as it provides an easy arrangement with a plurality of independently operated wave power generators.

In addition, it provides a system that is easy adoptable to changing conditions for the sea, ie that the waves increase or decreases, and thus provides an optimal construction with respect to efficiency.

Further, it provides an improved system in that wave power generator system is easy to install, inspect or maintenance.

The arrangement provides possibilities for different constructions/sizes/material of the floating element.

The system also may easily use existing infrastructure, for instance offshore facilities, where the same personnel are operating the oil production and the wave power generator.

The system may also easily be extended or changed to an optimal size.

The system may be dimensioned to operate during all weather conditions. It may adapt to all weather conditions by changing the buoyancy of the floating device. The floating device may also be filled with ballast water and moved to the wire carriage during extreme weather to protect the floating device.

The system may in addition have an arrangement for transferal of horizontal forces from the main wires into power.

The arrangement for transferal of the horizontal forces may further adapt to different wave heights or intensity of the wave.

Summary of invention

The invention relates to a wave power generator system comprising a top deck arranged on a foundation and a wave power generator arrangement. The arrangement comprises a first and second main wire extending between the top-deck and the seabed, a buoyancy arrangement comprising a floating device, a first generator sheave, second generator sheave, and a generator wire, the generator wire is connected at both ends of the floating device and extending in a loop via the first generator sheave arranged at the top deck and the second generator sheave adapted to be arranged below a sea surface, the floating device is adapted to be moved by waves along the first and second main wire causing the generator wire to rotate the first and second generator sheave,

a first generator is operationally connected to the first generator sheave transferring rotational movement to power in the first generator, the buoyancy arrangement further comprises a ballast water regulator adapted to automatically adjust the buoyancy in the floating device based on the wave heights or wave conditions acting on the floating device (16).

The invention is further related to a method for generating power using the wave power generating system. The method comprises the steps of adjusting the buoyancy in the floating device by introducing ballast into the floating device at measured increasing wave height with a maximum total weight (ballast and net weight) at an upper limit wave height value,

and removing ballast from the floating device at measured decreasing wave height with a minimum total weight (ballast and net weight) at a minimum wave height.

The upper limit value for the wave height may be based on the overall system, like the dimension and/or numbers of main wires and the dimension or size of the floating device.

Beyond the upper limit value of the wave height, there may be a removal of the ballast from the floating device.

Preferable embodiments of the system and method is set out in the accompanying dependent claims, to which reference are made.

Brief description of drawings

Figure 1 shows an overview of a wave power generator system according to the invention, side viewed,

Figure 2 shows an overview of a wave power generator system according to the invention, end viewed,

Figure 3 shows an embodiment of an anchoring device according to the invention,

Figure 4 shows a detailed view of the first and second main wires arranged between the top deck and the anchoring device,

Figure 5 shows a detailed view of the buoyancy arrangement according to the invention,

Figure 6a and b shows a detailed view of the floating device coupled to the first and second main wires, according to the invention,

Figure 7 shows a detailed view of the interior of the floating device according to an embodiment of the invention,

Figure 8 shows an overview of the wire carriage and wire base to which the buoyancy arrangement is coupled,

Figure 9 shows further a detailed view of the wire carriage and the wire base,

Figure 10 shows detail view of the safety device, ie connection between wire carriage and the wire base according to the invention,

Figure 11 shows a detailed view of the interior of one of the generator cells of the top deck, viewed front viewed,

Figure 12 shows a detailed view of the interior of one of the generator cells of the top deck, viewed from above,

Figure 13 shows a detailed view of the interior of a generator cell of the top deck, side viewed,

Figure 14 -17 illustrates different embodiments of horizontal wave power generator arrangements of the wave power generator system,

Figure 14 shows a first embodiment of the horizontal wave power generator arrangement according to the invention,

Figure 15a -15b shows a second embodiment of the horizontal wave power generator arrangement according to the invention,

Figure 16 shows a third embodiment of the horizontal wave power generator arrangement according to the invention,

Figure 17 shows a detailed view of the third embodiment of the horizontal wave power generator arrangement from figure 16.

Detailed description of the invention

The term “vertical wave power generator arrangement” is to be interpreted as the arrangement that generates power from the vertical or substantially vertical forces of the waves, ie the movement of the floating device in a direction between the seabed and top deck of the wave power generator caused by movement of the waves.

The term “horizontal wave power generator arrangement” is to be interpreted as the arrangement that generates power from the horizontal or substantially horizontal forces of the waves, ie the deviation from the horizontal positioning of the floating device caused by wind and/or waves.

The term “wave power generator arrangement” is to be interpreted as an arrangement including the vertical wave power generator arrangement and/or the horizontal wave power arrangement.

The term “wave height” is to be interpreted as the distance from the top to the bottom of a wave. The wave height further indicates the weather conditions, ie that the weather ie calm with small waves or extreme with larger waves.

Figure 1 shows a wave power generator system 1 according to an embodiment of the invention. The wave power generator system 1 shown has a top deck 2 and a foundation 4. The top deck 2 is arranged above a sea surface S, resting on the foundation 4. The foundation 4 is preferably fixed to the seabed.

The system may however also be a floater, but the system must then be a tension leg platform.

The top deck 2 may further be supported by platform bar(s) 5 extending vertically between the seabed B and the top deck 2 and platform wire(s) 6. The platform wire(s) 6 may preferably extend with an inclination between the seabed B and the top deck 2 to provide an additional support and stability for the top deck 2. The arranging of platform bar(s) 5 and wire(s) 6 are illustrated in the figure 1. The foundation 4, the platform bar(s) and the platform wire (s) may be made of steel.

The top deck 2 may also be made up by a plurality of individual generator cells 3. Each generator cells 3 containing a separate wave power generator arrangement.

Each vertical wave power generator arrangement may in its simplicity comprise at least to main wires 13, 14 and a buoyancy arrangement 7. These features will be described further in relation to the figures disclosing the features.

The top deck 2 of figure 1 is divided into two equal modules 2a. Each module 2a has 11 individual generator cells 3 arranged in the length of the top deck 2 in three vertical layers, ie 66 generator cell 3 in total in both modules 2a. Further, there may arranged two generator cells 3 in the width of the top-deck 2, ie on both sides as shown in figure 2. The total number in the illustrating example is thus 120. The number of generator cells 3 are obviously only a suggestion. There may be fewer or more generator cells arranged in the top deck 2. An exemplary size of the generator cells may also be 30 m in the length and 11,5 m width, and 25 m heigh. All of these being alternative embodiments of the invention.

The top deck 2 may also be extended by further generator cells 3 in the lengthwise direction. These may add further wave power generator arrangements, but may also contain other support equipment, such as crane, winch, escape chute, connection for walkway.

Figure 2 shows the wave power generator system 1 of figure 1, viewed from the end.

This figure further illustrates a first main wire 13 and a second main wire 14. The first and second main wires 13, 14 extends between the top-deck 2 and the seabed and is fixedly attached at both ends.

There may be a plurality of first and second wires 13, 14, each pair extending from individual generator cells 3. The plurality of first and second wires 13, 14 may be fixedly connected to the seabed B through one or more anchoring device 8.

The embodiment of the anchoring device 8 shown in figure 3 comprises a manifold 9 with a plurality of suction anchor 10 for connection with the seabed B. The anchoring device 8 may be arranged in parallel with the longitudinal side of the top deck 2.

The anchoring device 8 further has a plurality of first anchoring fastener 11 and a plurality of second anchoring fastener 12. The first and second anchoring fasteners 11, 12 being arranged at the opposite side surface than the suction anchor 10.

The first and second anchoring fasteners 11, 12 is adapted to respectively fasten the first and second main wires 13, 14 at the seabed.

As indicated in figure 4 (and fig.2), there may be a plurality of anchoring devices 8 arranged in parallel. This makes it possible to vary the positioning of the first and second main wires 13, 14 with respect to the top deck 2, ie the angular displacement of the first or second main wires 13, 14 from the top deck 2.

Figure 4 illustrates the plurality of pair of the first and second main wires 13, 14 from the platform 2. Is indicated in the figure 2 that each generator cell 3 may have a first and second main wires 13, 14 extending towards the seabed. This is however only an example of a possible configuration of the wave power generator system 1.

Figure 5 shows a detailed view of the buoyancy arrangement 7 according to the invention. The buoyancy arrangement 7 comprises a generator wire 15 and a floating device 16. The generator wire 15 is connected to the floating device 16 at both ends 20, 21, hereinafter named a first fastening point 20 and a second fastening point 21.

The generator wire 15 extends in a continuous line from the first fastening point 20 to the second fastening point 21. The buoyancy arrangement 7 further comprises a first generator sheave 17 and a second generator sheave 18. The generator wire 15 extends via these generator sheaves 17, 18. The first generator sheave 17 is arranged within the platform 2. The first generator sheave 17 is further in operational connection with a first generator G for transforming the rotational movement of the first generator sheave 17 into power.

The generator G may be a permanent magnet which will rotate and generate power when the floating device 16 moves.

The generator G may also be used as an electrical motor to pull up the floating device 16 for inspection and maintenance. It is preferred that the floating device 16 is self-draining to minimize the load for the motor in the pulling process.

The first generator sheave 17 may be arranged within each generator cell 3 as will be further illustrated and described in relation to figures 11-13.

The second generator sheave 18 may be connected to a wire carriage 40. The wire carriage 40 have a position below the sea surface S. As illustrated in the figure 5, the positioning of the first and second generator sheave 17, 18 with respect to each other, and the length of the generator wire 15 are chosen so that the generator wire 15 forms a substantially tight line. As will be described in relation to figure 13, the first generator sheave 17 is arranged on a platform 48 that with a mechanism to tighten the generator wire 15.

The floating device 16 is arranged at the sea surface S so that it is partly submerged in the sea.

To avoid wear and tear of the generator wire 15 on the floating device 16, there may be arranged a center generator sheave 19. This is preferably arranged on the outside of the floating device 16 to guide the generator wire 15 and avoid contact with the floating device 16.

Figure 6a and 6b shows the connection between the buoyancy arrangement 7 and the first and second main wires 13, 14. The floating device 16 may comprise U-profiles 25a, 25b at each longitudinal side of the floating device.

Figure 6a shows a detailed view of the U-profiles at one side of the floating device 16. The figure shows two oppositely arranged U-profiles 25a, 25b arranged to enclose the first or second main wire 13, 14. Each U-profile 25a, 25b is equipped with a roller bearing 26 and axial bearing 27 to facilitate the sliding of the floating device 16 along the first and second main wires 13, 14.

The figure 6b shows the slidably connection of the floating device 16 to both the first main wire 13 and the second main wire 14.

The floating device 16 is further divided into a buoyancy compartment 22 and a ballast compartment 23. The buoyancy compartment 22 is mainly arranged above the sea surface S, while the ballast compartment 23 is mainly arranged below the sea surface S. The ballast compartment 23 comprises ballast water that is adapted to be filled into and out of the compartment 23 depending on the surrounding environment. The buoyancy compartment 22 is mainly a dry area that contains among other things, equipment for adjusting the buoyancy in the ballast compartment 22. The buoyancy compartment 22 may be accessible through a hatch 24.

The buoyancy compartment 22 and the ballast compartment 23 are dimensioned with respect to optimal buoyancy.

Figure 7 shows a detailed view of the interior of the floating device 16 according to an embodiment of the invention.

The floating device 6 may comprise a ballast water regulator arrangement 37 comprising an air valve 32 and a pipeline 38 for guiding and controlling air or other gas into the ballast compartment 23.

The ballast water regulator arrangement 37 may optionally comprise a compressor (not shown) to force the air or gas into the ballast compartment 23 and consequently force water out of the ballast compartment 23.

Alternatively, the regulation ballast may be performed without a compressor, where the air valve 32 regulates the ballasting the floating device 16 directly. The air valve 21 may be opened when the floating device 16 is above the sea level S to reduce the ballast and further opened when the ballast compartment 23 is below the sea level to increase the ballast. The remaining time the air valve 32 is closed.

The floating device 16 may have a water opening 36 in the bottom part of the floating device 16 allowing water to move into and out of the ballast compartment 23 depending on the buoyancy requirement of the floating device 16.

The ballast water regulator arrangement 37 may further comprise a level transmitter 33 for measuring the level of water in the ballast compartment 23. The ballast water regulator arrangement 37 may further comprise a wireless communication 30 to transfer the signals and controlling the components between the top deck 2 and the individual floating devices 16 wave power generator system 1. In this way the floating device 16 may regulate the amount of ballast water in the ballast compartment 23 automatically.

An example of this regulating is described below under functioning of the system. As a general principle, however, the ballast water regulator 37 is by a control system (not shown) adapted measure the wave heights in the surrounding sea continuously and adapt the floating device 16 to these conditions to prove an optimal exploitation of the energy from the waves. This is done by introducing/ removing ballast to/from the floating device 16 based on the measured wave height or wave conditions. There will be an introduction of ballast with increasing wave height until an upper limit wave height is reached and a removal of ballast when the wave height decreases.

There may also be a decrease of the ballast when the wave height increases beyond the upper limit wave height to compensate for the increased deviation and a possible break of the main wires due to an increased weight of the floating device 16. The upper limit wave height may for instance be 70% of an uppermost extreme maximum height, but other percentage may be possible. The upper limit wave heigh is based on the size of the floating device 16 and the strength of the main wires 13, 14.

The floating device 16 may further comprise a solar panel 29 and battery 31 for providing power to the floating device 16. Further, it may also comprise a central lubricator supply to provide lubrication to rotating parts, such as the bearings 26, 27.

It also may comprise one or more transversal bulkheads 35 to shore up the floating device 35 against the waves and also provide a dampening of any waves of the ballast water within the floating device 16.

For the maintenance operation, the floating device 16 may comprise a screw jack 34 arranged in connection with the water inlet/outlet 36 to clean the inlet/outlet 36 and keep this open. The screw jack 34 may be operated from the buoyancy compartment 22 and extends through the ballast compartment 23 to clean the water inlet/outlet 36.

Figure 8 shows an overview of the wire carriage 40 and a wire base 42 to which the buoyancy arrangement 7 is coupled. The positioning of the wire carriage 40 with respect to the buoyancy arrangement 7 is shown in figure 5. The wire carriage 40 is adapted to be connected to the first and second main wires 13, 14 in a similar way as the floating device 16 as described in figure 6a and 6b.

The wire carriage 40 is adapted to slide along the first and second main wires 13, 14 onto a wire base 42. The wire carriage 40 has wire carrier connector 41 for connection with a wire base connector 43 on the wire base 42.

The wire carriage 40 is connected to the wire base 42 when the wave power generator system 1 is running producing wave energy.

The wire carriage 40 may however be pulled up for inspection and maintenance of the wire carriage 40. This may be performed by the first generator G in a similar way as with the floating device 16 as described above. The first generator G acting now as a motor.

The positioning of the wire base may be near the seabed or a positioning at the lower half of the sea.

The first and second main wires 13, 14 extends further from the wire base 42 towards the seabed B to be fixedly attached to the anchoring device 8 as described above.

The wire carrier connector 41 and the wire base connector 43 constitutes a connection arrangement 39. Figure 9 and 10 illustrates an embodiment of the connection arrangement 39. It is to be noted that the arrow A indicates the downward direction when the wave power generator system is installed.

The connection arrangement 39 comprises a carriage lock lever 44, a carriage lock 45 and a carriage lock spring 47. These features are arranged on the wire carrier 40.

The connection arrangement 39 further comprises the wire base connector 43 of the wire base 42. The wire base connector 43 may have the shape as a hook or similar to connect with the carriage lock 45.

The functioning of the connection arrangement 39 as shown in figure 9 and 10 is that a load may be lowered onto the carriage lock lever 44. The movement of the carriage lock lever 44 downwards due to the load will move the carriage lock from a closed position 45 to an open position 46. While in the open position 46, the wire carriage 40 may be lowered further down towards the wire base 42. When the carriage lock in the open position 46 is positioned so that it is able to connect with the wire base connector 43, the load is removed and the carriage lock spring 47 will force the carriage lock back into the closed position 45. This will connect the wire carriage 40 to the wire base 42.

Figure 11 – 13 shows detailed views of the interior of the generator cell 3 of the top deck 2, viewed from different angles. The figures illustrate the components of one single generator cell 3.

Figure 11 illustrated the generator cell 3 front viewed. The figure illustrates in detail a possible embodiment of the buoyancy arrangement 7 within the generator cell 3. The first generator sheave 17 is illustrated rotationally connected to a generator platform 48. The generator platform 48 may further be suspended from the roof or the generator cell 3.

Figure 12 illustrates the generator cell 3 from above. The first generator sheave 17 may have different positions as shown as 17 and 17’ in the figure.

There may also be arranged a third main wire (not shown) similar to the first and second main wires. When this third main wire is present, the first generator sheave must be arranged in the position 17’.

Further, the first and second main wire 13, 14 may be fixedly attached at the inner side wall or a structure 3a of the generator cell 3.

Figure 13 shows the generator cell from the side. In this view it is further shown that the platform 48 may be moved by a platform wire 49. The generator platform 48 may be rotationally connected at an end oppositely arranged from the first generator sheave 17, 17’. The platform wire 49 may thus be shortened or extended to move the end of the platform 48 with the first generator sheave 17. The shortening or lengthening may be performed by a weight or load. It is also possible to compensate the platform wire hydraulically.

This provides an automatic and constant tightening of the generator wire 15 in the system. This will further avoid that the generator wire 15 spins at varying conditions.

There may further be access to the generator platform 48 through stairs 50 and/or a hatch cover 51.

The functioning of the wave power generator system 1 will be described in the following:

The wave power generator system 1 is in working operation, ie generate power from the waves when the wire carrier 40 is connected to the wire base 42 below the sea surface S.

The buoyancy arrangement 7 is thus arranged between the top deck 2 and the wire carriage 40, by extending the generator wire 15 via the first generator sheave 17 and the second generator sheave 18. The floating device 16 is arranged at the sea surface S and is adapted to be moved by the movement of the waves in the sea.

This will cause generator wire 15 to move along the line extending through the first and second generator sheave 17, 18.

Consequently, the first generator sheave 17 will rotate due to the movement of the generator wire 15. Since the generator G is operationally connected to the first generator sheave 17, the rotational movement will generate power in the generator.

It is to be noted that the above functioning describes one buoyancy arrangement 7 with generator G, wire carriage 40 etc that are arranged in relation to one generator cell 3. The top deck may however comprise a plurality of generator cells, each having buoyancy arrangements 7 with attaching components. All of the buoyancy arrangements 7 works independently in the system 1 to generate power from the waves.

Further the buoyancy of the floating device 16 may be adjusted based on the size of the waves, ie the wave height. The adjustment may be performed automatically by measuring the parameters of the waves to adapt to optimal conditions for exploiting the energy at all wave conditions. The control of the ballasting of the floating device 16 provides a better phase control between the floating device 16 and the waves.

Based on the measured parameters of the waves, the ballast water regulator arrangement 37 may regulate the amount of ballast water in the floating device 16 to adapt to the different weather conditions as described in relation to figure 7.

As described above, the wire carriage 40 and the buoyance arrangement 7 are easy to pull up and inspect and maintenance. The same components are also likewise easy to install in the wave power generator system 1 with minimum equipment and installation time.

The system 1 provides a flexible wave generator arrangement by adding or removing generator cells 3 of the top deck 2. It is necessary to design the system in an optimal way, to utilize the energy most efficiently. To do this, the volume and water surface area of the floating device 13 must be as large as possible.

However, this will likely cause the horizontal wind and wave forces to exceed the resistance for breaking of the main wires 13, 14. This will consequently also put the whole system in risk. To avoid failures like this, it is important to dimension the system 1 by certain criteria and order.

The main wires 13, 14 sets the limit for the rest of the system 1. The main wires 13, 14 are then chosen by the necessary characteristic, dimension, numbers and quality compared to price.

The minimum resistance for breaking for the total number of main wires 1314 is found by deducting the safety margins of the total of main wires 13, 14. The minimum resistance represents the upper limit for the horizontal forces that may act on the floating element. The topside dimensioning and foundation must also safeguard these forces.

The floating device 16 may now be dimensioned based on the upper limit. The dimensioning must include the net weight, volume and design of the floating device 16 during worst case extreme weather conditions without ballast water.

The ballast water regulator arrangement 37 may be controlled automatically due to the wave height at the present time.

At minimum wave height, ie when there is a minimum of wave movements, there are almost no ballast in the floating device 16. The floating device 16 will then follow the waves with maximum buoyancy and minimum net weight.

As the wave height increases, the ballast water regulator arrangement 37 will allow water to be filled in the floating device 16 until reaching an upper limit wave height. This wave height is dimensioned to be approximately 10-30% below a maximum value based on the horizontal forces.

Further, increasing wave height beyond the maximum height will cause an emptying of ballast by the ballast water regulator arrangement 37 until the floating device 16 is completely empty from ballast. When the floating device 16 is completely empty of ballast, the energy transfer may be performed under extreme weather conditions, based on the dimensioning as set out above.

There may also be a failsafe, if the components of the buoyancy arrangement 7 should fail at the same time as extreme weather occur, an alarm will notify to fill up the floating device 16 completely and move the floating device 16 towards the wire carrier 40 below the sea surface S.

The wave power generator arrangement may further comprise a horizontal wave power generator arrangement.

Figure 14-17 shows various embodiments of horizontal wave power generator arrangements.

In general, equal reference numbering refers to equal features in all the illustrated embodiments.

Further, the first and second main wire 13, 14 are extending from the anchoring device 8 or a similar anchoring device to the top deck 2, as also illustrated for instance in fig 2, in all the embodiments. The main wires 13, 14 are further attached to a structure 3a of the cell 3 to which the main wires 13, 14 may be fixedly connected. The figure 14-16 shows equally sets of first and second main wires 13, 14 extending from each generator cell 3.

Further each first and second wire 13, 14 and optionally the third main wire (not shown) are equipped with separate generators or hydraulic cylinders.

In all embodiments, the horizontal wave power generator arrangement and the vertical power generator arrangement may have a common battery bank for the storage of power.

Figure 14 shows a horizontal wave power generator arrangement 70 according to a first embodiment. The embodiment is hereafter referred to as an electrical rotating generator arrangement 70.

The electrical rotating generator arrangement 70 comprises a hydraulic cylinder 72 attached between the main wires 13, 14 and the structure 3a.

The arrangement 70 further comprises a second generator system G1. The second generator system G1 comprises a first accumulator bank 73, a second accumulator bank 75, a hydraulic electric generator 77 and a hydraulic tank 78. The generator system G1 further has a pressure regulator and 74a and a pressure regulator valve 74b to control the flow of hydraulic fluid from the first accumulator bank 73 to the second accumulator bank 75.

The second generator system G1 also has a pressure control 76a and a pressure control valve 76b to control the flow of hydraulic fluid from the second accumulator bank 75. The second generator system G1 comprises pipes 81, 82, 83, 84, 85 for the flow of hydraulic fluid between the components 73, 75, 77, 78. In addition there is illustrates signal lines 87a, 87b, 87c, 87d between various components for the regulation the hydraulic flow.

The functioning of the electrical rotating generator arrangement 70 shown in figure 14 is the following:

When there is a pull in the main wire 13, 14, the hydraulic cylinder 72 will act as a hydraulic reciprocating pump with a spring return, pumping hydraulic fluid under pressure to the first accumulator bank 73.

The pressure regulator valve 74b is arranged between the first and second accumulator bank 73, 75. The valve 74b is further controlled by the pressure regulator 74a that set the limit pressure for opening the pressure regulator valve 74b. The pressure regulator 74a automatically adjust the set point, of the pressure regulator valve 74b based on a measured wave height.

The limit pressure for the pressure regulator valve 74b will increase, with increasing wave heights. This means that the pressure regulator valve 74b may open even at small waves when there is less pumping of hydraulic fluid from the hydraulic cylinder 72 due to small movement of the main wires 13, 14.

The hydraulic fluid further flows into the second accumulator bank 75 when the pressure in the first accumulator bank 73 is exceeds the pressure limit of the pressure regulator valve 74b.

Between the second accumulator bank 75 and the hydraulic electric generator 77, the pressure control valve 76b is arranged. The pressure control valve 76b is further controlled by the pressure control 76a. The pressure control 76a automatically adjust the opening of the pressure regulator valve 76b.

The pressure regulator valve 76b will thus open at an upper pressure H-1 and close at a lower pressure L-1. The value of the upper pressure and lower pressure are not constant but shifts by the different wave heights. This makes it possible to operate the hydraulic electrical generator 77 efficient in any wave heights.

By setting a higher-pressure limit H-1 for the opening of the valve 76b than for closing of the valve 76b, it provides some pressure built up in the system for the power generating process. This provides a more efficient energy transition the built up also gain momentum for the forces in the system to provide a longer period of operation of the generator.

The hydraulic fluid flows further from the hydraulic electric generator 77 when the pressure in the second accumulator bank 75 is above the lower pressure L-1. The hydraulic electric generator 77 will only rotate to produce power when the pressure is between H-1 and L-1.

The flow of hydraulic fluid into the hydraulic electric generator 77 provides the transmission into power in the generator 77.

It is to be noted that the pressure in the second accumulator bank 75 will always have a lower differential pressure than the first accumulator bank 73. This is due to the feeding of the hydraulic motor of the generator 77.

From the hydraulic electrical generator 77, the hydraulic fluid is adapted to flow into a hydraulic tank 78. The hydraulic fluid may then be reused into the hydraulic cylinder 72 by supplying fluid through the pipe 85 back into the hydraulic cylinder 72. The process may then be repeated.

The reference number 86 indicates connection of further pipes similar to the pipe 81 of other wave power generator arrangement. In this way, the arrangement forms a common generator system G1 for transmission of the horizontal force into power in the whole wave power generator system 1.

Figures 15a and 15b shows the horizontal wave power generator arrangement 90 according to a second embodiment. The embodiment is hereinafter named electrical energy transmission arrangement 90.

The electrical energy transmission arrangement 90 comprises the main wire sheave 71 and a second generator G2. The second generator G2 is in this embodiment operationally coupled to the main wire sheave 71 to transfer rotational energy from the main wire sheave 71 to electrical energy. This connection is illustrated in detail in figure 15a. The second generator G2 is connected to the same shaft as the main wire sheave 71.

The second generator G2 is a similar type generator as the generator G that is described in relation to the vertical wave power generator arrangement, ie a rotating permanent magnet generator.

The electrical energy transmission arrangement 90 comprises further an electrical screw jack arrangement 92. The screw jack arrangement 92 comprises an electrical screw jack 93, a screw jack sheave 94 and a tension spring 95. The screw jack sheave 94 is tensioned by a guidepost constituting the tension spring 95 and screw jack 93 in the end to provide a tensioning and slacking of the main wires 13, 14

The functioning of the electrical energy transmission arrangement 90 is the following: the first and second main wires 13, 14 extends from the seabed around respective main wire sheaves 71 towards the structure 3a. The screw jack arrangement 92 is arranged so that the screw jack sheave 94 bear against a part of the main wire 13, 14 arranged between the main wire sheave 71 and the structure 3a. The screw jack arrangement 92 will thus push this portion of the main wire 13, 14 downwards.

When the main wire 13, 14 are tightened by horizontal forces, the screw jack sheave 94 will move along the main wire 13, 14 once the pre-stressing force is exceeded. The main wire sheave 71 and the second generator G2 will at the same time start to rotate. The braking effect of the generator G2 comes into action and the generator then produces power to the battery bank. Without any braking effect the floating element would follow the waves in weightless condition and there would not be possible to exploit any energy.

Figure 16 -17 shows the horizontal wave power generator arrangement 100 according to a third embodiment. The embodiment is hereinafter named electrically linear arrangement 100. This provides the simplest embodiment of the horizontal power generator arrangements.

The electrically linear arrangement 100 comprises a linear permanent magnet generator G3. The linear permanent magnet generator G3 is preferably cylindrical. The linear permanent generator G3 is attached between the structure 3a of the cell 3 and the first and second main wire 13, 14, respectively.

The generator G3 resembles the hydraulic cylinder 72 from the first embodiment in figure 14.

The electrically linear arrangement 100 functions in a way that when the first and second main wires 13, 14 are tightened by horizontal forces, the linear permanent magnet generator G3 will move axially outwardly when the pre tensioning force have been exceed. The braking effect of the generator G2 comes into action and the generator G3 then produces power to the battery bank.

Figure 17 shows the electrically linear arrangement 100 viewed in greater detail. This figure shows a single electrically linear arrangement each attached to each of the pair of main wires 13,14.

How much of the horizontal forces that are possible to transfer into power in the system is dependent of the net weight, volume, design and ballast weight of the floating device 16. This means that the horizontal movement of the waves will push the floating element sideways by a force simultaneously as the floating device 16 moves vertically. The possible energy transfer is limited to the minimum resistance to breaking of the main wires 13, 14. However, it may be a considerable force that also result in a tightening and slacking of the main wires 13, 14 to generate power from the horizontal forces.

The system 1 may also take into consideration the sum of the horizontal and vertical forces when adjusting to an optimal buoyancy of the floating device at a specific wave condition or wave heights.

This may for instance be performed in the interval up to the upper limit wave height. In this area, the floating device may adopt to a higher total weight (net weight and ballast) than required for the specific wave height. However, the potential decrease in the energy transmission from the vertical forces may be gained by an increase in the horizontal forces at this wave height.

Above the upper limit wave height, there may generally be a reduction of the ballast to compensate for dimensions in the system, like the strength of the main wires 13, 14 and the size of the floating device 16. An further ballast increase of the floating device 16 will thus not be applicable in the area above the upper limit wave height.

Claims

1. A wave power generator system, characterised in that it comprises a top deck (2) arranged on a foundation (4) and a wave power generator arrangement comprising

a first and second main wire (13, 14) extending between the top-deck (2) and the seabed,

a buoyancy arrangement (7) comprising a floating device (16), a first generator sheave (17), second generator sheave (18), and a generator wire (15), the generator wire (15) is connected at both ends of the floating device (16) and extending in a loop via the first generator sheave (17) arranged at the top deck (2) and the second generator sheave (18) adapted to be arranged below a sea surface, the floating device (16) is adapted to be moved by waves along the first and second main wire (13, 14) causing the generator wire (15) to rotate the first and second generator sheave (17, 18),

a first generator (G) is operationally connected to the first generator sheave (17) transferring rotational movement to power in the first generator (G), the buoyancy arrangement (7) further comprises a ballast water regulator (37) adapted to automatically adjust the buoyancy in the floating device (16) based on the wave-heights acting on the floating device (16).

2. The wave power generator system according to claim 1, wherein the ballast water regulator (37) comprises a pipeline (38) for flow of gas and an opening (36) for the flow of water into and out of the floating device (16), the ballast further comprises a control unit for measuring the wave-height and regulating the amount of gas and water in the floating device (16) based on the wave height.

3. The wave power generator system according to claim 1 or 2, wherein the top-deck (2) comprises a plurality of generator cells (3), each generator cells (3) comprising separately arranged wave power arrangements.

4. The wave power generator according to claim 1, 2 or 3, wherein the wave power generator system further comprises a wire carriage (40) to which the second generator sheave (18) being attached.

5. The wave power generator according to claim 1, 2 or 3, wherein the wire carriage (40) comprising a wire base (42) adapted to connect the wire carriage (40) at a fixed position below the sea surface (S).

6. The wave power generator according to claim 1, 2 or 3, wherein the wave power generator further comprising an anchoring device (8) adapted to be arranged at the seabed for connecting the first and second main wire (13, 14).

7. The wave power generator according to any one of the claims, wherein each generator cells (3) comprising a generator platform (48) to which the first generator sheave (17) and the generator (G) is attached, the generator platform (48) being hingedly connected in one end and is adapted to tighten the generator wire (15) by moving the free end of the generator platform (48).

8. The wave power generator according to any one of the preceding claims, wherein the wave power generator further comprises at least one horizontal wave power generator arrangement (70, 90, 100), said horizontal wave power generator arrangement (70, 90, 100) being connected between the main wires (13, 14) and a fixed structure (3a) of the generator cell (3), respectively.

9. A method for generating power using the wave power system according to any of the claims 1-9, wherein the method comprises the steps of adjusting the buoyancy in the floating device (16) by introducing ballast into the floating device (16) at measured

increasing wave height with a maximum total weight of the floating device (16) at an upper limit wave height value,

and removing ballast from the floating device (16) at measured decreasing wave height with a minimum total weight of the floating device (16) at a minimum wave height.

10. The method according to claim 9, wherein the method further comprises the steps of additional generation of power by movement of the main wires (13, 14) due to horizontal movement of the floating device (16).