WO2020069725A1

WO2020069725A1 - Floating wave energy converter

Info

Publication number: WO2020069725A1
Application number: PCT/EP2018/076700
Authority: WO
Inventors: Giovanni Parnof
Original assignee: Giovanni Parnof
Priority date: 2018-10-01
Filing date: 2018-10-01
Publication date: 2020-04-09

Abstract

The present invention is a floating wave motor energy converter (fig. 1). The machine, lightweight, floating and easy to install, is hermetically sealed and made of marine-resistant corrosive materials; It leverages the ability to convert Fluid Dynamic Energy from whatever direction it comes from. Floating Units (fig. 2 - 1) allow to produce longitudinal, transversal and vertical stresses that affect only themselves or the entire machine. The machine is perfectly scalable and this makes it ideal for applications in any condition: open sea, proximity to the coast, smaller oceans and seas and then, independently by the deepness of the waters. The machine can be made in different configurations: the Stand Alone configuration (fig.12), the Wind Turbine Coupling configuration (fig.13) and that in which several machines are arranged in a raw or a mesh and every machine is connected to the others by a cable in a specified distance.

Description

FLOATING WAVE ENERGY CONVERTER

SUMMARY

Floating Waves Energy Converter based on a Carrier Structure, Floating Units and a Conversion System. The Carrier Structure rests on Floating Units free to oscillate. The oscillations of the Floating Units actuate the Hydraulic Operating Machines which generate high pressure in an high pressure Accumulation Tank. High pressure Accumulation Tank, with controlled pressure and flux, release fluid to actuate Hydraulic Conversion System and convert fluid dynamics energy into Electrical Energy by using the Generator.

BACKGROUND AND STATE OF ART

The wave energy conversion is the subject of several studies and technological systems and there are many electrical energy production devices starting from that marine motion.

Patent W02006079812 discloses about floating wave energy converter comprising a carrier structure and floating units. In it the floating units are simply spherical and the hydraulic system is exposed and not capable to convert omnidirectional wavy motions. The subject-matter of present invention therefore differs from this known apparatus because the different floating units, invented to improve the absorption of the kinetic energy of the sea waves while at the same time protecting the hydraulic system from the environment, and the different floating carrier which does not need a intervention at the bottom of the sea for installation and maintenance purposes.

Patent CN106640503 discloses an elastic membrane as part of a floating unit housing the hydraulic system. It seems that this system don’t permit oscillation of the floating unit and is capable to make only vertical movements to convert energy. The particular shape of the floating unit of the present invention and its inner Hydraulic System is intended to convert omnidirectional wavy motions thanks to a combined hydraulic system made by Floating and Fixed Branched Junction Elements.

Patents DE19612124 e WO2012050466 disclose hydraulic systems that are however not part of a floating energy converter. The shape of the floats employed therein is also different from that of the present invention.

Patent US0061179 A1 discloses a floating buoy system bound to a central joint at the base. This system is born to exploit the omnidirectional waves, but the presence of the mechanical members (hydraulic hoppers and hydraulic pistons) at the seabed makes this device hard to install and maintain. Patent CN101585568 A discloses a floating buoy system and hydraulic pistons. Even though the mechanical bodies above the surface of the water are presented, it is not conceived to exploit omnidirectional wavy motions, and is suitable for situations of only mono directional motions.

Patent GR0100197 has a branched floating structure with buoys that capture energy radially by requiring operations to external units subject to the wearer's action.

The need to increase conversion efficiency by maximizing conversion from omnidirectional motions, having a more easily installed and maintainable system and increasing the quality of converted energy by means of a stable and controllable conversion leads to the idea of a new system that exceeds the limits of the previous ones. DRAWINGS LIST

1 . Sea iso view

2. Detailed iso view

3. Plant view

4. Section view

5. Floating Unit - iso view

6. Floating Unit - Prospect view

7. Floating Unit - Plant Secction

8. Hydraulic Operating Machines - Section view

9. Floating Unit - Detailed Prospect Section 1

10. Floating Unit - Detailed Prospect Section 2

1 1. Hydraulic Operating Machines - Detail

12. Stand Alone Configuration

13. Wind Turbine Coupled Configuration

14. Wind Turbine anchorage phase

15. Telescopic Stabilizers Tensioners - Detail

STRUCTURE

Assy - Overall, the machine has a Carrier Structure with several different geometric shape which can also be branched. From the Central Carrier Structure (fig.2-2) the Rigid Supporting Arms (fig.2-3) (in variable number) start to arrive at the Floating Units (fig.2-1). The connection to the Floating Unit is carried out via the Joining Body (fig.4-10) which is rigidly tied to the end of the Support Arm and by a Spherical Joint Junction (fig.4-11) at the base of the Floating Unit. In this way, the Floating Unit is free to oscillate both longitudinally and transversely with fulcrum at its lowest point. Binding guides avoid angular motions around the axis of the Joining Body. The Concentric Cylinder System (fig.7-20) allows the Floating Unit to move vertically along the Joining Body approaching and moving away from the Rigid Support Arm. Complete the Joining Body with a threaded bar (fig.10-9) for adjusting the operating distance between the Arm and the Floating Unit and leveling the machine.

Carrier Structure - The Carrier Structure (fig.3-2) is the operating base of the instrumentation. It has an annular configuration with several faces and the number of which depends on the number of Floating Units (fig.3-1) employed for the specific application and in its central part is drilled to eventually permit pylon anchoring. On it stand the hydraulic and electrical apparatus. It is always at a positive rate with respect to the top of the sea. Its buoyancy is guaranteed by the Self-Stabilizing Configuration: the Floating Units arrangement is such as to ensure in any condition that 3 or more Floating Units are always floating. Moreover, the anchorage at the bottom of the sea or to the pylon of the Wind Turbine, oppose resistance to the reversing weather preventing potential critical situations. Rigid Support Arms - The Rigid Support Arms (fig.3-3) are not strictly necessary but, if present, are in fact the Extensions of the Carrier Structure and are fixedly connected to it. The minimum number of arms of the machine is 6 but this number, depending on the conditions of application, may increase. In larger machine models, in calm water conditions, they can let operators reach the Floating Units from the Carrier Structure and vice versa.

Equipment Cabinet - All the equipment is contained within a cabinet made of light and durable material. The summit of this cabin is designed for the assembly of modules that contribute to the supply of energy used for the operation of on-board systems. The generated energy, as accumulated in suitable accumulators, is sufficient to ensure the operation of the Supervision System even for long periods without energy capture. In any case, it is possible to drain part of the energy produced by the Hydraulic Generation System.

HYDRAULIC AND PNEUMATIC CIRCUIT

Assy - The hydraulic circuit (fig.3-6) is a closed system. The carrier fluid fills the whole circuit and it is mostly contained in the Accumulation Tanks (fig.3-4). There are one or more High Pressure Accumulation Tanks and eventually a Low Pressure Accumulation Tank. Through the Hydraulic Operator Machine System (fig.8-25), Floating Units push carrier fluid into the high pressure tanks from which, at controlled pressure and flow, it is sent to the Hydraulic Conversion System (s) (fig.3-5) and then it is collected in the Low Pressure Accumulation Tank and return to the Floating Units.

Hydraulic Operator Machine - The Hydraulic Operator Machine (fig.11) has a Return duct (fig.11-33) and one Mandate due (fig.11 -32), intercepted by non-return valves (fig.11-34) in contrast, for each room in which it is divided by the piston. Both rooms (fig.11-35) work alternatively as Push and Pull Room.

Hydraulic Operator System - The set of hydraulic machines form the relevant System (fig.8). This system, using floating movements and, along the path of the joining body, pushes the carrier fluid from the Floating Unit to the High Pressure Tank, drawing it from the Low Pressure Tank.

Mandates / Returns - Along the Joining Body between Floating Unit and Arm and along the Arm, the pushing circuit from the Floating Unit to the High Pressure Accumulation Tank (fig.4-12) and the return circuit from the Low Pressure Accumulation Tank to the Floating Unit (fig.4-13) run. In addition to the primary circuits, there is also auxiliary pneumatic circuit routed only to the Floating Units for compressed air provision. From the High Pressure Accumulation Tank to the Hydraulic Conversion System runs the Production Circuit (fig.3-7). From the Hydraulic Conversion System to the Low Pressure Accumulation Tank runs the carrier fluid Recovery Circuit (fig. 3-8). Bypass valves are available between circuits to exclude each Floating Unit from the production process. Accumulation Tanks

High Pressure - The machine may be equipped with one or more high pressure Accumulation Tanks. Inside these tanks the carrier fluid is pumped from the Hydraulic Operator System. From these tanks, through controlled rolling valves, the carrier fluid is sent, at pressure and controlled flow, to the Hydraulic Conversion System when the internal pressure of the chamber is such as to guarantee a minimum operating time T even in the absence of motion Wavy. When all High Pressure Tanks are in a dispensing condition and the energy from the wave motion is to exceed that in the Hydraulic Conversion System, the Auxiliary Conversion System may be activated to increase the conversion to Electric Energy.

Low Pressure - The Low Pressure Accumulation Tank, if present, is the collecting area of carrier fluid that is output from the Hydraulic Conversion System. From here the carrier fluid will be called up in Floating Units.

Hydraulic Conversion System - To convert Dynamic Fluid Energy to Electric Energy, a Hydraulic Conversion System is used. Depending on the size of the machine, the appropriate type of Converting System is used according to the available flow rate and fluid flow regimes.

Compressor - To prevent marine water or corrosive marine air from coming into contact with the movable parts and others subject to corrosion, hermetic rooms at positive DR are identified on the machine. The compressor, by means of an auxiliary pneumatic circuit, guarantees the positive DR where necessary, such as water and / or aeriform can be refractory, even in case of anomalies, to come in the housing. The occurrence of an anomaly on the housing is detected by the Control System which, while operating the compressor to withstand the pressure loss, signals the alarm via the Communication System. Inert gas can be used to pressure the rooms.

FLOATING UNIT - The Floating Unit (fig. 5) is the peripheral element of the system directly exposed to wave action. It is designed to exploit and convert longitudinal, transverse, and perpendicular force components to it. A number of floating Units free to move independently of one another hold the whole machine out of the water. At the bottom of the hermetic chamber inside the Floating Unit, sensors ensure monitoring of fluid leaks from the hydraulic circuit.

Hermeticity / Controlled Pressure - The Hydraulic Operator Machines are contained in the Hermetic Chamber (fig.8-21) of the Floating Unit. None of the movable mechanical parts is exposed to the corrosive action of external agents. This condition is guaranteed by the room airtightness and internal controlled pressure. The compressor guarantees the positive DR in the Floating Unit using also inert gases. Advantages - The System ensures easy and quick installation. Maintenance is facilitated since all elements, except for the ballasts in the Stand Alone Configuration, are out of the water. The deterioration of the mechanical system organs by the atmospheric agents is absent due to the presence of inert atmosphere in the Pressurized Hermetic Rooms and to the use of suitable materials for the outer casings. The System ensures also a better efficiency in wave energy conversion from omnidirectional wavy motions and, thanks to the Accumulation Tanks, improves energy quality avoiding discontinuity in energy supply.

ELETTRICAL SYSTEM

Service Generator and Accumulators - Due to the small need for energy required by the Control System, a small field of capturing modules is used, which, on the top body of the machine, allows to optimize the energy capturing. This service generator is realized considering proportionality factors between consumed energy and energy produced to ensure permanent power supply to the Control System. Specific accumulators are designed to provide, at full charge, several days of operation of the Control System in the absence of production.

Control System - The Control System is the responsible part for monitoring and supervising the system parameters and operating conditions.

Through the use of specific sensors it read and measure

• climatic conditions (wind, temperature, humidity)

• leveling of the System

• system position

• the energy produced by the Service Generator

• the power available to the Service Generator

• the charge value of the accumulator

• the energy produced by the primary and secondary generators

• the power available at main generators

• flow carrier fluid in flow and return

• circuit pressures

• pressures of the hermetic rooms

• the pressure of the Accumulation Tanks

Sensor values are stored in an internal database that is periodically backed up via the Communication System. These data are also used locally by the computer to begin the production and transfer the energy collected from Floating Units or to identify critical situations and take the necessary actions (eg Compressed Air Compressor Drive to withstand a leak from the hermetic rooms) and communicate the status of the machine in real time via the Communication System. Communication System - To ensure remote control of the machine, the communication system has a dual channel: Terrestrial and Satellite. The absence of one will involve the use of the other and, in case of simultaneous presence, one or the other will be used as per priority criteria based on service tariffs, bandwidth, goodness of connection.

Shipping System - The energy produced by the System will be sent to the ground by a specific power line or using the one of the wind turbines where this is present. A conditioning and predisposition circuit is the interface between the power line and the machine.

DETAILED DESCRIPTION FLOATING UNIT GEOMETRY

The geometry of the Floating Unit has 8 main faces. All them have pyramid trunk and horizontal circumferential cross section. They also develop in concave form. For the upper 4 (fig. 5-14), the lower, horizontal section grows downwards, while for the lower 4 (fig. 5-15), the higher, the horizontal section grows upward. Both, the 4 upper faces and the lower 4 are connected to each other at 90° angles (fig.7) to form closed ring groups. The upper and lower annular groups join respectively the lower and upper base to form an acute angle (fig. 6-17) along the line on which the floating unit floats. The lower bottom base is a spherical shell portion (fig. 6-18), while the upper one is an elastic and hermetic membrane (fig.6-19) crossed by the Joining Body to the structure.

The entire geometry of the Floating Unit wrap develops in two layers, one inside the other (fig .8- 22,23). Each layer corresponds to surfaces that, together with separating sets, forms watertight chambers (fig.8-24) with the corresponding surfaces of the opposite layer. Its surfaces delimit inside the hermetic chamber (fig.8-21).

Hydraulic Operator System - The Hydraulic Operator System (fig.8) is made up of pairs (opposite to the Joining Body) of Hydraulic Operator Machines (fig.8-25) arranged vertically with respect to the float plane. Couples are divided into two groups: Upper and Lower. For both groups, propulsion chambers face downwards while stems face upwards.

The Upper Group is anchored at the bottom by means of adjustable joints (fig.9-26) to a Branched Joining Element (fig.9-27), rigidly integral with the Joining Body (fig.9-10). Above, other adjustable joints, anchor it to a Floating Branched Junction Element (fig. 9-28) around a sliding joint (fig.9-29) on the Joining Body. This Floating Junction Element, by means of tie rods (Figures 9-31), is maintained in parallel configuration with the inner bottom of the Floating Unit.

The Lower Group is instead anchored at the bottom by means of adjustable joints at the bottom of the Floating Unit (fig. 9-30) and at the top by adjustable joints to a Binding Joining Junction Element (fig .9- 32), rigidly integral with the Joining Body.

In oscillatory movements (typical of calm waves), opposing pairs operate in inverted rooms: pumping one corresponds to the suction of its counterpart and vice versa. In vertical movements (typical of waves with high heights) both work in synchronism by pumping or aspirating from the room in the same position. The number of pairs and their displacement varies depending on the resilient action exercised by the Floating Unit and depending on available spaces. Different number of pairs can be arranged at different angles, maintaining the same possibilities of movement. The operational configuration is based on the specific application conditions to maximize Hydraulic Operator Machine movements and efficiency of the energy conversion.

Telescopic Stabilizer Tensioner System - The anchorage system at the wind turbines requires the use of a tie to be attached to the pylon supporting three telescopic rods (fig.15-1) attached to the Carrier Structure.

Claims

[1 ] 10-faces Floating Unit comprising 8 elements with pyramid trunk plant and horizontal circumferential cross-section that develop in concave form, 1 spherical shell portion bottom base and 1 elastic membrane as top base.

[2] Floating Unit according to claim 1 characterized by 4 upper elements, the lower, with horizontal section growing downwards, 4 lower elements, the higher, with horizontal section growing upwards and connected to each other to form two annular structures, concave outwards, to pairs, respectively, with the lower and upper base to form an acute angle between them along the floating line.

[3] Floating Unit according to claims 1 and 2 characterized by a double layer of metal (external and internal) to form stagnant rooms between the layers and locating inside a hermetically sealed chamber delimited by a flat base at the bottom, on which the Spherical Joint Junction is fixed, and by an elastic membrane at the top.

[4] Floating Unit according to claim 1 ,2 and 3 comprising a Hydraulic Operator System comprising Couples (opposite respect to the Joining Body) of Hydraulic Operator Machines arranged vertically with respect to the float plane and subdivided into two groups (Upper and Lower) with lower chamber propulsion elements and upper stem

[5] Floating Unit according to claim 1 ,2,3 and 4 comprising a Hydraulic Operator System characterized by

- an Upper Group bound downward with adjustable joints at the ends of a first branched junction member rigidly integral with the Joining Body and upward with adjustable joints at the ends of a second branched junction element floating around the Joining Body but, by the use of tie rods, in a parallel configuration with the inner bottom of the Floating Unit;

- a lower group bound downward with adjustable joints integral to the flat base of the Floating Unit and upward with adjustable joints at the ends of a third branched junction element rigidly integral with the Junction Body

[6] Floating Waves Energy Converter, characterized by a structure for solitary operation, pylon coupled operation and in line or mesh operation comprising Floating Units according to claims 1 , 2 and 3 housing inside Hydraulic Operator Systems according to claims 4 and 5.

[7] Floating Waves Energy Converter according to Claim 6 characterized by a minimum number of Floating Units equal to 6 and Hydraulic Operator Systems with a minimum number of operating pairs equal to 2.