ES2564743A1 - Wave converter, with float, of low inertia, with pre-immersion system, and mechanical accumulator of rotating double-turn energy mounted in the transformation and accumulation train. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

The object of the invention is an energy converter of sea waves in electrical energy, comprising a guided float that moves linearly vertically in an alternative way and that transfers the energy during the entire upward travel of the float, through a system low-inertia mechanical, to a double-turn rotary mechanical energy accumulator. To achieve greater energy use, it has a partial pre-immersion system of the float, adjustable according to the height of the waves and the tide, acting before every upward movement of the float, triggered by an electric motor, is initiated. The structure of the converter will be mounted fixed on the shoreline or on a floating structure anchored near the coast (nearshore). (Machine-translation by Google Translate, not legally binding)

Description

OBJECT OF THE INVENTION

The present invention relates to a sea wave energy converter in electric energy, which comprises a guided float that moves linearly vertically in an alternative manner and transfers the energy during the entire upward travel of the float, through a low-inertia mechanical system, to a double-turn mechanical energy accumulator.

15 To achieve greater energy use, it has a partial pre-immersion system of the float, adjustable according to the height of the waves, acting before each upward movement of the float begins.

The structure of the converter will be fixed fixed on the coast (shoreline) or on a floating structure anchored near the coast (nearshore).

20 SECTOR OF THE INVENTION

Source ~ of renewable energy. Harnessing the energy of the seas. Wave energy. Clean energies.

25 BACKGROUND OF THE INVENTION

Renewable marine energies constitute energy sources of enormous potential but are very poorly developed. In the current state of the art there are many devices designed to take advantage of marine energy 30 also known as energy from the seas or oceans. Some take advantage of the energy of the brands (marcomotive), others the energy of oceanic thermal gradients (OTEe), others osmotic energy (from salinity gradients), others marine wind energy (produced by marine winds), others the energy of marine currents (inertial) and finally others, such as that proposed by the invention,

35 that take advantage of wave energy also known as wave energy or a motor di.

As for the emplacement with respect to the coast,

i) some are mounted in deep waters (> 50m), away from the coast (offshore), submerged or afloat, both anchored;

ii) others in shallow waters (10-40 m), near the coast (nearshore), floating anchored or with a structure supported at the bottom and

iii) others are mounted on the rocks on the shoreline.

The energy associated with the waves varies from one area to another. It is greater between the 30 ° and 60 ° parallels of both hemispheres. On the Galician and Cantabrian coast, the average value exceeds 40 kW per m of wave front.

The first patents for wave exploitation date back to 1799 in France (Girard and son), and in Great Britain in 1833. Today they exceed one thousand.

As for the float devices (they only take advantage of the potential energy of the waves, not the kinetics) a classification would be [Chozas, P. 29]:

~ Totalizer or terminator: Long converters placed parallel to the wave front, perpendicular to the direction of the wave (eg Duck Salter). They eliminate the incident wave, behind them there is only the wave radiated by the body in its oscillation.

~ Dimmer: with e! axis of! converter in the forward direction of the waves, with the ability to self-orientate (eg Pe! amis). Attenuate, do not eliminate, the incident wave.

~ Punctual absorber: with dimensions much smaller than the wavelength of the waves. They take advantage of the vertical oscillation (ex. OPT of Santoña)

In the process of transferring wave energy into useful energy with float converters, it is possible to distinguish [Chozas, P. 37J a primary conversion:

• from the movement of the waves (with a period of around 10 s) a float moves in a vertical direction (with a speed of about 2 m)

and a secondary school, usually with one of these proposals:

•

and! float drives the piston of an air compressor, which is sent to a pressure vessel or,

•

the float drives the piston of a pump that pumps liquid to an elevated tank or a pressure tank that will then be turbinated to drive an electric generator, or,

•

The float directly drives the translalor of a linear generator. This solution Today, it is unsatisfactory.

As regards float converters, in all current designs the energy use is reduced because, among other reasons, it is not possible to transfer all possible floating displacement energy in the shortest time available.

On the other hand, it is not known, through the available bibliography, of any converter through a float that incorporates a system of pre-immersion aj 5 depending on the height of the waves, to increase the energetic apTOvechamiento.

DESCRIPTION OF THE INVENTION

The lffidimotor converter that the invention proposes pennite, with respect to current converters, increase energy efficiency.

The object of the invention is a wave energy converter in electric energy, with a float and a low inertia mechanical interface to the first energy accumulator which also comprises a system that acts by partially submerging the float, depending on the height of the waves, before each upward float tour begins. In figures 1, 2 and 3 3 possible alternatives of the

15 aspect of this wave converter, with float, low inertia, with pre-immersion system (WEC-FLI-PIS).

The period of the waves, T, is about 10 seconds. When the wave reaches the converter, an increase in the water level in the chamber where the float that drives the float up, but the time that the water remains remains

20 near its upper level is very scarce. The transfer of energy to the accumulator must take place in the short period of time that goes from when the water level in the chamber begins to rise until it reaches its maximum (let's call it "ascent time"). To allow time for this brief interval to transfer energy, a converter with mechanical transmission is designed from the float to the energy accumulator 25. This mechanical transmission is made with low inertia elements (reduced mass in the train elements with linear displacement and low moment of inertia in the train elements subjected to rotation). The use of any fluid as an element for energy transfer to avoid viscous friction is avoided.

The energy that is transferred during the ascending path - "ascending race" 30 is given by

E {/ = rF'ds

,

where F is the force of Archimedes, buoyant force; CI the lower limit of the upward stroke and C2 the upper limit. To maximize this expression, it is that both F and the difference between the limits of integration are the greatest possible.

35 As an electric generator, any rotary, direct or alternating, single-phase or three-phase, synchronous or induction generator can be used. The induction generator is especially suitable for this type of converter

fed (DFIG) (39) because it allows adjusting the rotation speed of the rotor of the

generator using the frequency of rotary currents that are introduced through

dc1 rotor side converter (54) and thus be able to adjust the torque in the accumulators of

energy (24), (30) Y (34), as depicted in Figure 4.

5

The way in which this invention addresses the reduction of the time of this process,

"ascension time" is to achieve, as just said, the conversion with a

very low inertia design of the train elements to the first accumulator and for

the elements with linear displacement are made with very little mass and the

elements with rotary movement with very low moment of inertia.

10

To maximize the use per meter of wave front, the float is designed with

prismatic shape, except at the bottom of the float (which is

permanently submerged) which will be hydrodynamically shaped (omitted in the

attached figures), to reduce pre-inrnersion work.

When the wave in the converter is in its valley position (position 1 of the

fifteen

Figure 7) The float lowers naturally to its lower free position, floating in

rest, the submerged float volume being practically zero. It is from this

moment when starting order is given to the pre-immersion electric motor that

immerse the float until the buoyant force, was Archimedes,

balance the antagonist torque of the first energy accumulator (position 2 of the figure

twenty

7). It should be part of the float emerging. The immersion depth of

float, for maximum utilization, is related to the height of the

wave, Hw, distance from crest to valley. The weight of the float must be very small, for

Simplicity of explanation is going to assume negligible float weight. As first

approach, immersion depth to get e! maximum use

25

energy is equal to the height of the wave. Once the desired immersion is achieved, it is cut

pre-immersion motor power. The time to immerse the

float must be, at most, the time that remains e! water level in your level

lower. Once power is removed to the pre-dive engine, if the water

remains at its lower level, the float will not move because the buoyant force

30

it will be insufficient to overcome the antagonistic pair of the first energy accumulator,

position 3 of figure 7.

When the water level in the chamber starts to rise, the float volume

submerged will increase and therefore also the strength of Archimedes will increase, therefore

the balance will be broken and now the float will begin its ascending career, exercising

3S

a constant force, FF, vertical and up. This linear displacement is

will transmit to the accumulator (24), for example as the one represented in the

Figures, rotating the axis of the first rotary mechanical accumulator (28). Ideally,

The float will move in unison with the wave. Therefore, if the water rose in the chamber a

height Hw, the float will have moved vertically up the same distance

40

Hw (position 4 of Figure 7) equal to the upper integration limit minus the limit of

bottom integration. The energy transferred to the accumulator, according to what has been said, will be:

Eu = rF · ds = F, · H "(J)

5

When the water level returns to its lower position, the float will fall to its resting position in floating (5), homologous to (1). The net energy, E, that can be obtained from the converter, during the period of the wave, T, will be the energy transferred to the accumulator, Eu, according to the expression (2), minus the energy consumed in the float immersion process, ED .

The average power obtainable, P, during the period of the wave, will therefore be:

p = Eu -Ef) T

(W)

10

A converter like the one described could be built with a fixed structure on the shore (shoreline), this would be the most reasonable option for a high-power plant, but for units of reduced power, floating units near the coast (nearshore) could be mounted ).

1 S

BRIEF DESCRIPTION OF THE DRAWINGS

twenty

To complete the description that is being made and in order to help a better understanding of the features of the invention, a descriptive and non-limiting set of figures is attached as an integral part thereof.

25

There are 2 alternatives for the wave energy converter in electric energy, with float and pre-immersion system (WEC-FLI-PIS) for riding on the coast, Figures 1 and 2. A floating WEC-FLI-PlS converter anchored, figure 3; the train of transformation and accumulation, figure 4; a detail of a mechanical double-speed rotary energy accumulator (ARDG), figure 5; a wave of Airy with the representation of ascending work path, figure 6; and a more real representation of the coastal waves with the most representative work points, figure 7.

30

-Figure 1 shows the simplified profile of the wave energy inverter in electric energy, with float and pre-immersion system and a low inertia mechanical interface to the first rotary accumulator to be fixedly fixed on the coast. It includes a spiral spring upward accelerator (optional).

1-Seawater level

2-Float

35

3-Float mast

4-Power transmission chain 5-Cogwheel 6-Chain tension maintainer 7-Motion Accelerator Chain

5 8-Cogwheel 9-Upward accelerator 10-Pre-dive chain 11-Pre-dive motor 12-Pre-dive motor starter

10 13-Anterior guide wall 14-Wheels 41-Steering gear 42-Steering gear 55-Motor shaft with, optional, ratchet mechanism.

15 56-Booth

-Figure 2 is analogous to Figure 1 but with force transmission from the float with traction cable. 15-Traction cable in downward travel. 16-Cable end hook eye.

20 17-Upward traction cable 18-Traction cable guide 43-Beginning chain connection node

-

Figure 3 represents e! Simplified profile of the wave energy converter in

25 electric power, with float and pre-immersion system and a low inertia mechanical interface to the first rotary accumulator to be mounted afloat, anchored, near the coast. It includes a spiral spring upward accelerator (9) (optional). The submerged baffle plate (46) can also be seen, as a guide for the incident wave, fixed to the structure in order to increase the travel of!

30 float. And also the braking plate, submerged, horizontal (47), fixed to the

structure in order to stop the vertical displacement of the converter when the wave reaches the converter. The depth of the sea is not to scale. 45-Floating structure 46-Baffle plate 5 47-Braking plate with vertical displacement. 48-Anchor Chain

49-Dead -Figure 4 represents the train from the gearwheel (8) to the electric generator (39), together with the converters on the network side (53) and the rotor side (54); the control unit

10 (51) of the pre-dive motor (11), the starter (12) and the control unit (52) of the converters. All these elements, for simplicity, are not represented in figures 1, 2 and 3.

20-motion rectifier 21 - Toothed wheel

15 24-Double-turn rotary accumulator (ARDO) 25-Cogwheel wheel 26-Pinion 27-Shaft input to second accumulator 28-Shaft input to first accumulator

20 29-Pinion 30-Rotary double-turn accumulator (ARDO) 31-Rucda toothed crown 32-Pinion 33-Axis to third accumulator

25 34-Double-turn rotary accumulator (ARDO) 35-Cogwheel wheel 36-Pinion 37-Shaft 38-Rotor shaft coupling 39-Rotary electric generator

40-Mains

51-Pre-immersion motor control unit

52-Drive control unit

5 53-Network side converter

54-Rotor side converter

-

Figure 5 represents one of the possibilities of constitution of the mechanical double-turn rotary energy accumulator of low inertia and with the possibility of

10 rotation speed multiplication (ARDG) (24). The shaft (28) and the outer gear ring (25) always rotate in the same direction. In the spring (23) the accumulation of energy occurs, in the form of elastic energy.

-

Figure 6 depicts an Airy wave with the representation of the upward work path, starting from the pre-dive.

15 - Figure 7 is a more real representation of the coastal waves with the most representative work points.

DESCRIPTION OF A PREFERRED EMBODIMENT

20 The particular location shown in Figure 1 will be described. In a zone of coast beaten by the waves, a converter with a fixed structure is mounted that allows free vertical movement, along the chamber, of the prismatic float, lightweight and preferably corrosion resistant material.

25 To avoid collisions between guides and float, wheels are mounted on it on all sides. The mast is mounted on the upper face of the float. Inside the float a light metal structure can be mounted that adequately transmits the efforts to the base of the mast and the float can also be filled with expanded polyurethane foam to give it consistency.

30 For the weight to be reduced, the mast should be hollow. As a material, painted aluminum can be a good option. The knot of chain hooks to the mast can be a reinforcement piece welded to the mast

When the water level inside the converter chamber rises, the float will move with upward movement, the chain (4) is subjected to traction, with a very high tension (depending on the volume of the float it can be of the order of several tonings ) and rotate the wheel (8) in a dextrogyric direction. As can be seen in Figure 4, the mechanical rectifier will transmit the torque to the wheel (21) that is engaged with the pinion (29) that drives the shaft (28) of the first double-turn rotary accumulator (24). For each revolution of the wheel (8), the axle (28) will have turned several revolutions, for example 6. The wheel (21) must be carefully designed so that its moment of inertia is reduced. The shaft (28) will rotate in a levographic direction and flex the spiral metal spring (23) accumulating mechanical energy. The spring container cylinder can rotate and by means of the fixed gear ring on its outside (25) it will transmit the rotation to the pinion (26) to which it is engaged. For every 6 revolutions of the shaft (28), the pinion (26) and the shaft (27) will have rotated, for example, 60 revolutions. With two

10 more stages of accumulation-multiplication, the electric generator will have rotated for each revolution of the wheel (21), for example, 6000 revolutions.

To facilitate the upward movement of the float and reduce the rise time, an upward movement accelerator can be mounted, marked with (9) in Figure 1, consisting for example of a spiral spring with an end fixed to the cylinder

15 static container and the other end fixed to the axle of the wheel (5) on which the chain (7) that pulls the float assembly vertically upwards during the upward travel is mounted.

The upward movement of the float (2) will continue as long as the water level continues to rise. When the water level in the chamber drops, the float 20 will also drop by gravity. During the downward travel of the float, the chain (4) will be barely without tension and will move downwards thanks to the counterweight (6), turning the wheel

(8) Levógiro sense. This levographic rotation of the wheel (8) will not be transmitted to the wheel (21) thanks to the interposition of the mechanical rectifier (20) of Figure 4.

When the water level reaches its lower level and the float is "resting" on the

25 water, detected by the water level and float position sensors respectively, the control unit (51) of figure 4 gives the starter (12) of the pre-immersion motor (1 1) a start command

Once the pre-immersion motor (11) starts, it tensiones the chain (1 O) conveniently directed by the pinion (42), pulling the mast down by 30 in the hitch knot and moving the mast assembly. Ilotador down, Once the notor is submerged to the adjusted depth, the control unit (51) gives the stop command to the pre-immersion motor (11). At that time it will be in an equilibrium situation since the Archimedes force is not enough to rotate the input shaft (28) of the first accumulator (24). When the water level in the chamber begins to rise, the wet surface of the float increases slightly and therefore the new Archimedes force is already sufficient to rotate the shaft (28). During the upward travel of the float, the chain (10), being the pre-immersion motor without power, is practically without tension. The pre-immersion motor shaft, being without power, allows the rotation without difficulty during the displacement

40 ascending the chain (10). It is not necessary, but is optional, the use of ratchet mechanism (ratchet) on the gearwheel of the motor shaft (55).

If the height of the waves that reach the converter decreases, the pre-immersion depth of the float should be reduced, as explained above. The variation in the wave period does not affect the optimum pre-dive depth. A decrease in the height of the waves will cause the input torque on the axis of the electric generator to decrease (having decreased the thrust force of the float) and also its rotation speed. In the event of a decrease in the height of the waves, if the electric generator is a DFIG (39), the frequency of the rotary currents must be increased so that the rotational speed of! generator, adjusting the rotor side converter (54). If the height of the waves does not vary but e! wave period

10 increases, the optimum depth of pre-immersion does not vary nor therefore the input torque to the electric generator but also the convertible power decreases and the frequency of the rotary currents must be increased.

An indication of the energy accumulated in the first double-turn rotary accumulator

(24) and the torque available for the generator is obtained through the measurement of the angle

15 between two "marks": one on the shaft (28) and one on the housing of the first rotary accumulator (24). The signal of two transducers is sent to the control circuit (52) and will be used to adjust the control signal for the network side converter (53) and for the rotor side converter (54).

The embodiment of Figure 2 is analogous to that of Figure 1, but in Figure 2 the

The transfer of energy from the float to the first accumulator (24) is done with cable working only on traction. The advantage with respect to Figure 1 is that the total maSa in alternative vertical displacement is smaller, therefore the acceleration may be greater and the time required to proceed with the transfer of energy from e! float to the smallest accumulator; another advantage in figure 2 is that

25 the height necessary for the booth (56) that houses the machinery is much smaller. As a drawback in Figure 2, it is that it needs fixed anchor points and bearings (18) in the pennanently submerged volume.

The embodiment of Figure 3 is a floating WEC-FLI-PIS converter anchored, with float and mast (another embodiment would be with float and traction cable, that is, as 30 in Figure 2, but afloat). Because it is floating, Figure 3 does not need to be designed to work with tides and therefore the length of the mast does not need to be as high as in the case of the converter with a bottom-supported structure (Figure 1). To increase the vertical travel of the float, a wave router (open-arm concentrator, not shown) can be placed towards the oscillating water chamber and a deflector plate (46), inclined, facing the incident wave front, for the wave to rise to a higher level. It is interesting that when a wave arrives at the converter it does not rise, for this it is provided with a brake plate (47) at the bottom of the converter that stops the vertical movement. To provide a lot of inertia to the converter, the framers of the structure (45) can be partially ballasted. I dont know

40 represents the electrical cable connecting to the network (40). Instead of pouring electrical energy to the general grid on land, an alternative would be to use the electrical energy obtained in producing hydrogen in the same converter.

Figures 1, 2, and 3 are simplified figures, representing only the fundamental components. They also do not represent the machinery represented in the figure

4. The prismatic float (2) in the upper part may have a hydrodynamic, pyramidal or conical shape in the lower part.

As a tension-keeping element at the chain ends (6), small masses or spiral springs can be used.

The terms in which this report has been described must always be taken in a broad and non-limiting sense.

Claims (8)

l.-Mechanical accumulator of double-speed rotary energy multiplier (ARDO) comprising an energy input axis, receiving the mechanical input power with unidirectional, continuous or impulse rotation, and on said axis an end of the elastic accumulator element, metal strip or other material, in spiral, and the other end of the spiral fixed to the inner face of the cylinder that contains it; the outside of said cylinder mounts a circular, concentric, toothed crown and with the rotation of the whole assembly in the same direction of rotation as the axis, transmits the movement with a turn 10 continuous and constant to a pinion, through gear or by chain or drive belt. 2.-Wave-type water column waveform converter, with float, with pre-immersion system, and with double-turn rotary mechanical energy accumulator mounted on the trans-accumulation and accumulation train (WEC-FLI-PlS) to be mounted by 15 fixed structure on the coast line, or near the coast by floating structure, comprising a float, which moves vertically alternately, upward-downward stroke, following the movement of the water surface and mechanically transferred the energy from the float through the mast-chain-toothed rucda-rotation rectifier-speed multiplier mechanism at a 20 ARDO accumulator according to claim 1, for each upward stroke and which includes a partial immersion system of the float, adjustable according to the height of the waves and the tide, before starting each upward course of the float, operated by a electric motor. 3.-Wave water column waveform converter, with float, with system 25 pre-immersion, and with mechanical double-energy rotary energy accumulator mounted on the transformation and accumulation train (WEC-FLl-PIS) to be mounted by means of a ftia structure on the coast line, or near the coast by structure floating, comprising a float that moves vertically alternately, upward-downward stroke, following the movement of the water surface and 30 that mechanically transfers the energy from the float through the flexible cable mechanism working with traction-chain-cogwheel-spin-speed multiplier to an ARDO accumulator according to claim 1, for each upward stroke and which includes an immersion system partial float, adjustable depending on the height of the waves and the tide, before starting each tour 35 float up, powered by an electric motor. 4. Waveform converter (WEC-FLI-PIS) according to claims 2 or 3 comprising an accelerator of upward movement, constituted by a counterweight, which vertically pulls up the float assembly throughout its travel. 5. Waveform converter (WEC-FLI-PIS) according to claims 2 or 3 which comprises an upward motion accelerator, consisting of a spiral spring with a fixed end, which vertically pulls up the float assembly along its entire length. . 6. Waveform converter (WEC-FLI-I'IS) according to any of claims 2 to 5, comprising a prismatic shaped float on its upper part and a hydrodynamic, pyramidal or conical shape on its lower part, for decrease pre-immersion work. 7. Waveform converter (WEC-FLI-PIS) according to any of claims 2 to 6, comprising small masses as tension keeping elements acting on the free ends of the chains. 8. Waveform converter (WEC-FLI-PlS) according to any of claims 2 to 6, which comprises spiral springs as tension maintaining elements acting on the free ends of the chains. 9.-Wave converter (WEC-FLI-PlS) according to any of claims 2 to 8, comprising a double-fed induction generator as an element 15 for setting the sturdy torque of the double-turn rotary mechanical energy accumulators (ARDO).