JP5656155B1 - Multihull type tidal current power generation facility - Google Patents

Abstract

[PROBLEMS] For tidal current power generation, the optimum design guideline derived from the viewpoint of optimum single unit capacity has not been established yet, and a highly maintainable technology when using a large number of power generation units is presented. There were few. A multihull type tidal current power generation facility according to the present invention uses as a platform a floating body of a multihull type including a catamaran having a structure in which a main body is constructed on land and a power generation unit can be inspected and repaired at sea. A power generation panel composed of a large number of standardized power generation units with a small unit capacity and geometrically packed together is suspended in the sea and operated. In addition, mooring by two mooring lines originating from one foundation on the sea floor, and by selecting the mooring position in the hull, the hull pitching due to the reaction of the power generation load and yawing in the horizontal plane can be suppressed as much as possible. Provide a possible geometric structure. Tidal power generation can be realized by integrating current shipbuilding technology and plant construction technology, and it is suitable as a small-scale tidal power generation demonstration ship and a medium-scale commercial tidal power generation facility. [Selection] Figure 1

Description

The present invention relates to a tidal current power generation facility that converts kinetic energy of a fluid of a tidal current such as the Kuroshio into rotational energy by a hydro turbine or the like and converts it into electric energy by a generator.

Tidal current power generation and wind power generation have a common point by converting fluid kinetic energy into electrical energy. Wind power generation is used in land and in shallow water, and it is already in the late stage of growth when applied to the product life cycle, and a power generation nacelle with a huge windmill on a long cylindrical column is installed so as to be able to swivel. Is converging on global standards.

Tidal current power generation is a theme that attracts attention as a natural energy after wind power generation. When applied to the product life cycle, it is in the early phase of introduction, and many ideas for thought and experiment have been proposed, some of which have been prototyped or entered into verification tests. It has not yet been seen what system will become the global standard in the future.

  Japanese Patent Application Laid-Open No. 2004-068638

Report on Joint Research “Research on Ocean Current Power Generation” Marine Science and Technology Center Tokyo Electric Power Company September 1981

The Kuroshio Current has a strong current zone that extends from the sea surface to a depth of about 200 m and covers a width of 100 km. Moreover, it is known that the tidal current has relatively little daily fluctuation and seasonal fluctuation. Unlike solar power generation and whimsical wind power generation that can generate electricity only on sunny days, if it can be used in earnest, it will become a reliable and stable energy source, and will bear a considerable part of the energy that Japan needs. It has been pointed out that it can.

As will be described later, if a hydro turbine using a convergence and divergence nozzle is used, tidal power generation of 10 kW per m 2 can be performed from a tidal current of 2.5 m / s. If a large tidal current power generation facility supporting underwater that uses up to 200m of water depth is built, it is theoretically possible to extract several million kW of power per 1km of width. As a trump card, it is worth considering feasibility.

Wind power generation with generators at a high position from the surface of the earth has been developed in the direction of increasing the unit capacity, but is the same thing happening with tidal power generation? It is the first object of the present invention to understand the difference between the characteristics of wind power and tidal current, to find the optimum single unit capacity of tidal power generation based on fluid engineering, and to provide a technology for actually loading such a power generation unit. .

The biggest reason why the large-scale tidal power generation plan is currently a dream story is that the demand for ocean development has not been revealed so far, so the technology, experience and equipment to develop a sea of several hundred meters deep are currently available. Because it is not in place. Rather than waiting for those environmental conditions with high social and technical hurdles to be achieved, tidal power generation will become the main energy source by realizing a small tidal power generation facility that is now possible with existing technologies. It is the second object of the present invention to provide a technique for opening up the breakthrough.

Means for solving the first problem will be described. In wind power generation, there was a direction of pursuing economic efficiency to increase the capacity of a single unit. Based on the design philosophy that it is the best way to improve. Let's explain the reason using mathematical formulas.
The energy P (W) obtained from the motion of the fluid is according to equation (1).
P = (1/2) ρ · A · V3 · η (1)
Where ρ is the density (kg / m3), A is the working cross-sectional area (m2), V is the fluid velocity (m / s), and η is the overall efficiency. This equation shows that the output that can be extracted from the motion of the fluid is proportional to the working cross-sectional area A of the fluid.

Since the density of seawater is about 1000 times that of air, tidal power generation that can obtain the same output as wind power generation at a wind speed of 10 m for the same area corresponds to a seawater speed of 1 m. There are many sea areas along the coast of Japan where the Kuroshio current has a flow velocity of 2 to 3 m. These are equivalent to the situation where strong winds of 20 to 30 meters are stably blowing from the same direction throughout the year in terms of wind power, and there is a great potential.

If the flow rate is 2.5 m and the overall efficiency is 0.6 in equation (1) and the working cross-sectional area of the turbine is reduced to half of the area of the inlet using a convergence and divergence nozzle, the flow cross-sectional area is increased to 5 m. A numerical value is derived that about 19 kW of power can be obtained per square meter.

Under this condition, the thrust that the turbine receives from the tidal current due to the power generation load is derived as about 1.2 tonnes per 1 m2 of the tidal cross-sectional area by the definition of (work amount) = (force) × (distance).

Now, let's express the dimension as L, the area as L2 and the volume as L3. In the case of the same shape design, the output of the power generation unit is proportional to the L square (area), and the required material amount is proportional to the L third power (volume). Consider a large machine that is 10 times larger than L, while maintaining the same shape design. The output of a large machine that has been increased 10 times is 100 times proportional to the area, but the required amount of material is required to be 1000 times proportional to the volume. In the basic design for a certain tidal current cross-sectional area, if 100 power generation units can be arranged, the total required material amount is only 100 units. In a large machine, one power generation unit can provide the same output as 100 basic design power generation units, but the required materials are equal to 1000 basic design power generation units. The output per required amount of material is one-tenth that of a basic design power generation unit for a large machine with 10 times the dimensions. Large power generation units are significantly less economical than small power generation units. As can be understood from the above explanation, when tidal current power generation is put into practical use, it is not desirable from the economical viewpoint to increase the unit capacity. Rather than installing one power generation unit having a square cross section with a side L of 50 m, the total cost of the power generation unit is roughly larger when 100 power generation units having a square cross section with a side L of 5 m that can obtain the same output are installed. One tenth is enough.

Then, if the capacity of a single unit is reduced as much as possible, the economic efficiency will be improved. The cost of the structure and surrounding facilities that hold these power generation units seems to be almost neutral to the unit capacity of the power generation unit. The more you do it, the stronger the negative impact from the underwater environment, such as the impact force of waves and the like, the attachment of shells and the entanglement of seaweeds. Each planner will determine and determine the optimum single unit capacity based on comprehensive judgment from the manufacturing, control and maintenance activities. The design parameters will eventually converge to a certain range through demonstration tests and the like.

If the unit capacity of the power generation unit is several tens of kW or several kW, the turbine may be a die-cast product such as aluminum, a plastic injection-molded product or an FRP press-molded product, and the casing may be a stamped product. Conceivable. Compared to the power generation unit with large single-machine capacity by custom-made processing, the latter with small single-machine capacity is overwhelmingly economical because mass production technology can be applied in addition to the inverse scale merit based on the square-cube rule described above. Are better. As described above, it is the core part of the solution means according to the present invention for the first problem to set the required number with a small single machine capacity.

Means for solving the second problem will be described. In the future when tidal current power generation will be used in earnest, the structure of tidal current power generation facilities is tens of thousands of power generation units between a large number of support structures launched from the seabed at equal intervals across the tidal current. It seems that it will be a huge facility with an output of tens of millions of kW. In this subsea-supported tidal current power generation facility, the power generation unit must be maintained while in the sea, and a strong support structure is installed on the bottom of the sea to resist the enormous thrust received from the tidal current as a reaction of power generation. Is necessary, and the hurdle of realization is high at present.

If the scale of power generation is in the range of several thousand kW to several tens of thousands kW, a tidal power generation facility based on a ship moored on a seabed foundation is possible. In the present invention, a power generation panel called a power generation panel, in which a large number of power generation units with a small unit capacity are densely loaded and loaded in a flat shape, is suspended and fixed from the ship during operation, and is generated during movement of the ship. By pulling the panel up to the sea and performing the necessary work while maintaining it up to the sea during maintenance, the inspection and repair work that was difficult because it was underwater in the underwater support type would be lifted up to the sea instead of underwater. It is a means for solving the second problem according to the present invention that is facilitated by the above. In order to make this solution means a reality, the following incidental new technology will be described below.

The power generation panel is a large rectangular structure, and is a multihull structure including a catamaran so that it can be suspended in the sea or pulled up to the sea. The horizontal side of the power generation panel is placed between two adjacent hulls of the multihull ship, and the vertical side of the power generation panel runs along the longitudinal direction of the hull. The power generation panel rotates a quarter of the axis supported by the adjacent hull, takes a vertical position with respect to the hull during power generation, and the main part is submerged, and takes a horizontal position during movement or maintenance. And is stored away from the sea surface.

A structure that integrates two adjacent hulls at sea is called a deck. When viewed from above, the deck that covers the sea surface is provided to avoid the place where the power generation panel is pulled up and fixed. Substation equipment that handles the power sent from the power generation panel, hydrogen generation / storage plant that will be the load of the power, workshops and storages that repair the power generation unit, and other facilities necessary for operation are installed on the deck .

In order to attach and detach the power generation unit from the power generation panel that is fixed horizontally during maintenance, an attachment / detachment device similar to an overhead traveling crane is provided across the two hulls. The detachable device removes the power generation unit from the power generation panel and transports it to the repair factory on the deck, or pulls the power generation unit from the storage, and attaches and fixes it to a predetermined position of the power generation panel. This operation is the same in appearance as the operation for inserting and withdrawing fuel rods from the reactor core. This operation is a mechanism that is performed by one-touch motion. Electric power and signals are exchanged between the power generation panel holder and the power generation unit by mechanically attaching and detaching the power generation unit by a non-contact electromagnetic coupler or the like.

The power generation unit is basically composed of one hydroelectric generator per unit, but if a mechanical and electrical interface with the above-mentioned holding body can be maintained by design, a plurality of smaller hydroelectric generators can be assembled. It may be integrated. This may be done for operational reasons. This corresponds to “Claim 3” of “Claims”.

Above the space occupied by the horizontally fixed power generation panel, there is no deck, so it can be an open space, but if necessary, as a building structure that covers the whole, it can work without being affected by day and night or the weather Can be configured.

The purpose of tidal power generation was to produce electrical energy. How to use the electrical energy produced in offshore facilities depends greatly on the energy demand structure of that era. At present, when there is a fear of power shortage, we would like to send it directly to the demand area as direct power by means such as DC transmission if possible. However, in many cases, this tidal current power generation facility operates far away from the land, and the site may be changed by moving as a ship due to circumstances such as the large meandering of the Kuroshio Current. Is often unsuitable.

At present, there is a movement toward the hydrogenated society in the developed countries. At this facility, the priority purpose is to separate the water into hydrogen and oxygen by electrolysis and transport the hydrogen to the demand area by tanker. There are businesses that have already put into practical use the technology to liquefy hydrogen and transport it by sea at normal temperature and pressure, and social systems for hydrogen production, transport and consumption are being prepared.

What about oxygen produced at the same time as hydrogen? There is a significant amount of demand in the rocket industry fueled by oxygen and hydrogen. Demand is also expected for gasification and melting furnaces and carbon dioxide underground thermal power plants. If there is still a shortage of oxygen demand, it will unfortunately be released into the air.

This facility produces a large amount of hydrogen. It contains trace amounts of deuterium and tritium. These are related to the use of nuclear energy, and the demand is uncertain, but it is also possible to separate them from the produced hydrogen by membrane separation or centrifugation to use them as resources.

During stormy weather such as a typhoon, there is a risk that the hull will be tossed by waves and the mooring lines will be momentarily subjected to high tension and cut. In order to avoid such danger, the mooring point should not be rigid, but a mechanism that softly allows the mooring line to move and brakes the energy received from the waves while braking. Such a mechanism can be easily realized by electric control, but it is desired to be designed as intrinsically safe as possible in case of an equipment failure or power failure.

During stormy weather such as a typhoon, the power generation panel and the power generation unit mounted on the power generation panel will not be damaged due to the impact of waves. On the other hand, if the power generation panel is in a suspended state, the center of gravity of the hull will be at a very low position, and it is certain that the risk of the hull's swinging and overturning due to the impact of waves will be reduced. In any case, when a typhoon strikes, we want to run the turbine idle without taking the power generation load and receive the mechanical blow as much as possible.

The present invention shows that a method of arranging a large number of small turbine generators in a state where they are integrated in a power generation panel is excellent in economic efficiency, rather than arranging a small number of large turbine generators in tidal power generation, and so on. A new technology required for tidal power generation that can cover small to medium power output with a combination of currently available industrial technologies through a multihull type tidal current power generation facility equipped with a flexible power generation panel.

It is a front view of a multihull type tidal current power generation facility. (Example 1) It is a side view of a single panel multihull type tidal current power generation facility. (Example 2) It is a side view of a twin panel multihull type tidal current power generation facility. (Example 3) It is a front view of a power generation panel. Example 4 It is a vertical fragmentary sectional view which passes along the central axis of an electric power generation unit. (Example 5) It is a 45-degree slanting plane fragmentary sectional view which passes along the central axis of an electric power generation unit. (Example 5)

FIG. 1 is a front view of a multihull type tidal current power generation facility according to the present invention. In this figure, 200 power generation units 3 are mounted on a holder 2 which is a part of the power generation panel 1. A mounting front view of the holding body 2 and the power generation unit 3 is shown in FIG. 4, and a side sectional view of the power generation unit 3 is shown in FIG. 5 and FIG. In the example of FIG. 1, two hulls 4 arranged in parallel have a catamaran structure in which an upper structure 5 is integrally formed. Substation equipment and hydrogen production plant that processes the power sent from the power generation unit 3, such as a deck that integrates the two hulls, and a detachable device, repair space, and storage for the power generation unit 3 on the deck A space for personnel who perform maintenance and management of various facilities such as ship maneuvering and power generation panels is housed in the upper structure 5.

The two mooring lines 6 have reached one bottom of the seabed that does not appear in the drawing, and are only shown halfway in FIG. In this invention, the construction of the facility is carried out on land, and the maintenance of the facility is carried out at sea.At present, the stance is not related to the underwater where technology and experience are insufficient. The installation and removal work of the cable is an area where we have almost no experience of large-scale construction so far, and the depth of water is more than 300m, but it must be realized by all means. It is a submarine foundation that is subjected to a tensile force of tens of thousands of tons, and has a different dimension of force from the anchor mooring a ship.

At present, there is no technology or construction equipment that can build a huge foundation on the seabed at a depth of 300m to 1000m. There is also a rocket anti-hand, but there is no track record in the tens of thousands of tons, so at present it is difficult to adopt. Although it is out of the scope of the present invention, this submarine foundation is constructed on the ground by the mega float method, towed or self-navigated, and is submerged like a submarine and submerged and landed on the seabed as a submarine foundation. I think the method will be the most realistic. If it is necessary to change the site, air can be injected into the interior to float and move, which is preferable. Although it is a large scale building with its own weight of several tens of thousands of tons, most of it can be expected to have a simple structure with many repetitions and low construction costs, including an electric propulsion device installed inside, a storage battery, a tidal current generator, The technology required for electronic equipment has already been put into practical use for deep-sea exploration boats and has a proven track record. It is certain that the current shipbuilding industry can build.

The mooring lines 6 are connected to the hull at mooring points 7 on both sides of the hull, and moor the hull at a predetermined position against the tidal current via a mooring arm 8. Two mooring lines 6 approach each other on the bottom of the sea, and when they approach the hull, they reach a mooring point 7 that is wider than the hull. Therefore, when viewed from above, the two mooring lines 6 and two mooring points 7 are An elongated isosceles triangle is formed. This geometric structure generates an azimuth restoring force that prevents the structure, which is a short side of the triangle formed by the two mooring points 7, from moving in a direction deviating from the tidal current. In the case of a ship, it is a geometric structure that has a function of restraining yawing of the hull by exerting a restoring force so that the hull always moves toward the tidal current. This corresponds to part of “Claim 4” of “Claims”.

The greater the distance between the mooring points, the greater the azimuth restoring force. For this reason, in a small scale facility such as a test ship, the mooring arm 8 can be lengthened to obtain a large restoring force. If such a facility removes the mooring line from the submarine foundation and stores it on the ship, sails off the mission and navigates the sea, or approaches the base, the mooring arm is stored parallel to the hull, etc. Provide a solution to narrow This corresponds to “Claim 6” of “Claims”.

Although the above-described measures can ensure the azimuth recoverability of the hull, the power generation panel generates a large Karman vortex behind it, and as a reaction, the entire facility tends to yaw in a short cycle. In order to minimize the effect of this phenomenon on crew members and facility plants, the degree of freedom in the horizontal plane on the bow side can be more firmly limited. Focus on the two hulls on the left and right ends of the multihull. A narrow auxiliary mooring line is stretched from the vicinity of the bow of the leftmost hull to the left side at an inclination angle of, for example, about 45 degrees, and a small left auxiliary submarine foundation is provided at a position reaching the seabed and moored there. A similar auxiliary mooring line is installed on the right side from the bow of the rightmost hull, and a right auxiliary submarine foundation is installed and moored there.

These two auxiliary mooring lines are almost perpendicular to the thrust vector of the tidal current applied to the power generation panel, and are usually tensioned so that the auxiliary mooring lines do not loosen. When the bow movement due to yawing sometimes exceeds the limit, the auxiliary mooring lines are pulled from the left and right auxiliary submarine foundations to suppress the bow movement. In this case, the tension applied to these auxiliary mooring lines is relatively small and is several hundred tons or less, and the tensile strength of the auxiliary mooring lines is not required to be as high as that of the mooring lines. We want to adopt a mooring method with a braking action so that shocking force is not applied to the mooring point of the auxiliary mooring line. This corresponds to “Claim 7” of “Claims”.

The power generation panel 1 is a general term for a large number of power generation units 3, a holding body 2 for mounting and fixing them in a predetermined place, and a strong frame structure for holding them. In FIG. 1, the power generation panel 1 is shown suspended from the space between the two hulls 4 by the rotating shaft structure 9. There is a tip 10 at the bow of the hull 4. The distance between the two hulls is narrowed from the tip 10 toward the rotary shaft structure 9, and a state in which a kind of conversion nozzle is configured can be read from FIG. The upper structure 5 is always designed to be above the sea surface 11.

FIG. 2 is a side view of a single panel multihull tidal current power generation facility having one power generation panel. The front view is FIG. 1 and shares the front view with FIG. The tip 10 is on the upstream side of the hull 4 and the tidal current flows from the right side to the left side in FIG. The power generation panel 1 is suspended from the vicinity of the buoyancy center of the hull. The case where the power generation panel is pulled up to the upstream side with the rotary shaft structure 9 as the rotation axis is referred to as a front storage type, and the case where the power generation panel is pulled up to the downstream side is referred to as a rear storage type. Both are technically valid. In the case of the forward retractable type, when the power generation panel is suspended, surplus buoyancy is generated on the bow side and the lift is lifted. In the case of the rear storage type, when the power generation panel is suspended, a surplus of buoyancy is generated on the stern side and lifts. In FIG. 2, the propulsion pod 12 is visible on the stern side of the hull, and the thruster 13 is visible on the bow side.

The space where the power generation panel 1 inside the upper structure 5 is pulled up is used for storage and maintenance, and this space occupies a large area close to half of the inside of the upper structure 5. The other space is used as a space for personnel who perform maintenance and management of various facilities such as power receiving / transforming facilities and hydrogen production plants, ship handling and power generation panels.

A part of the lower part of the suspended power generation panel 1 in FIG. 2 is a sectional view. The power generation unit 3 which was square from the front in FIG. 1 shows a rectangular side in FIG. The two hulls can be designed to have a low fluid resistance, but the power generation panel 1 has a considerably large fluid resistance when suspended. In order for the facility to remain in place, a large tension is applied to the mooring line 6. When the power generation unit starts power generation, a power generation load is added thereto.

In the numerical example used in the description of the above formula (1), the fluid resistance at a power generation output of about 19 kW per m 2 was about 1.2 tons. If the effective vertical length of the power generation panel of the tidal power generation facility in Fig. 2 is 100 m and the effective width is 50 m, the effective tidal area is 5000 m2, and power generation is included in the total thrust received from the tidal current when the power generation output is 95,000 kW. Assuming that the load due to the load is 6000 tons, the resistance of the hull that is not involved in power generation is ignored, and the hydrodynamic load of the power generation panel is assumed to be 4000 tons, it receives a horizontal thrust of 10,000 tons in total, When the angle of the mooring line is 30 degrees, the tension applied to the mooring line is about 12,000 tons, and the downward vertical component of the tension, that is, the load that the power generation panel for the hull receives from the tidal current is about 6000 tons.

Since the thrust applied to the power generation panel 1 is a distributed load, assuming that the effective length from the buoyancy center of the hull is 100, about 10,000 tons in the horizontal direction at a position of about 70 (reciprocal of square root 2) from the buoyancy center. The same rotational force as the concentrated stress is applied to the hull. Even when the buoyancy is very large, the bow sinks and the stern rises greatly.

Fortunately, there is a position of the mooring point where this rotational force can be neutralized by the downward vertical component of the mooring line. In this numerical example, assuming a horizontal line toward the rear of the hull, an upward force of 10,000 tons is applied to the position 70 from the buoyancy center by rotational force, and the position 118 from the buoyancy center toward the stern. If a 6000 ton weight is loaded downward, the rotational force is neutralized, and the hull remains in a horizontal state and the same state as when a new weight of 6000 ton is added. The mooring point 7 in FIG. 2 is provided at a position closer to the stern because the mooring point is placed at the position of neutralizing the rotational force. Normally, if a mooring point is provided on the stern side, the bow side will be swept away by the tidal current, making it difficult to maintain the posture on the horizontal plane. In order to solve this problem, it is necessary to provide mooring points 7 on both sides of the aforementioned hull, and to form a mooring line 6 drawn from the seabed foundation and an elongated isosceles triangle. These correspond to “Claim 4” of “Claims”.

FIG. 3 is a side view of a twin panel multihull type tidal current power generation facility in which two power generation panels of the power generation panel 1 and the rear power generation panel 14 are suspended on the bow side and the stern side, respectively. The front view is FIG. 1 and shares the front view with FIG. The rotating power generated by the power generation panel, which has become a problem in the single-panel multihull type tidal power generation facility, is canceled by each other at the center of the two power generation panels. The effect of will not appear. For this reason, the mooring point 7 can be provided in the center of buoyancy.

The twin panel system has a gravity balance in the longitudinal direction with respect to the hull when the power generation panel is retracted and suspended, and the mooring point has moved to the bow side from the single panel system. The attitude stability regarding pitching and yawing as a hull is remarkably high. Even if the power generation capacity is doubled, the amount of materials used is expected to be less than doubled. The problem is that since the rear power generation panel 14 on the stern side receives Karman vortex generated by the power generation panel 1 on the bow side, the power generation unit faces the turbulent flow. The influence is related to many factors, such as the flow velocity of the tidal current, the shape of the power generation panel, and the distance between the power generation panels, and it is necessary to carefully examine the adoption of this plan.

FIG. 4 shows an enlarged part of a front view of the power generation panel 1. Here, the outer frame portion of the power generation panel 1 is not shown, the holding body 2 made integrally with the power generation panel 1 is shown in black, and 12 power generation units 3 that are detachably attached and fixed thereto are shown. The power generation unit viewed from the front is a power generation nacelle 16 indicated by a small circle in the center, four pylons 17 supporting the power generation nacelle, five blades of a hydro turbine 18, and a large circle on the outer periphery thereof. Illustrated as the throat of the version nozzle 19. The state seen from the side is shown in FIGS. 5 and 6 described later.

In this figure, let's assume that the power generation panel is lifted to the sea level and is ready for maintenance. The attachment / detachment device performs predetermined positioning with the same movement as the overhead traveling crane, extends a pantograph-type arm downward, and presses the attachment / detachment manipulator at the tip against the power generation unit 3. The operation releases and releases the fixing mechanism that has fixed the power generation unit to the holding body 2 by pushing the fixing release rod of the power generation unit 3. Next, the manipulator lifts the power generation unit 3 by hanging a hanging bracket on the fastener of the power generation unit 3, moves to a predetermined position, and moves to the next operation. The installation of the power generation unit 3 is the reverse operation. The attachment / detachment device moves to a predetermined position, suspends the power generation unit 3 in a predetermined holding body 2, retracts the suspension fitting that has suspended the power generation unit 3, removes it from the fastener of the power generation unit 3, and attaches / detaches as it is. When the manipulator rises, the above-described fixing release rod pushed by the detachable manipulator is released and returns to the original state, and the positioning rod is pushed into the holding body 2 to firmly fix the power generation unit 3 to the holding body. The above description is given as an example, and there are many other design plans for the attachment / detachment mechanism of the detachable manipulator and the power generation unit 3.

FIG. 5 is a partial cross-sectional view passing through the central axis of the power generation unit 3, and FIG. 6 is a partial cross-sectional view along a 45-degree oblique plane passing through the central axis. A total of four pylons 17 and turbines 18 are shown in the outline view in the vertical and horizontal directions that support it. The seawater received by the entire cross-sectional area directly facing the tidal current including the holding body 2 and the power generation unit 3 is a convergence / divergence nozzle 19 formed inside the casing 15 constituting the outer shape of the power generation unit 3, and the power generation nacelle 16 When the turbine 18 is driven through the water channel between them, the speed is increased about twice as long as the dimensional relationship shown in the figure. When extracting electrical energy from the kinetic energy of the fluid, it is worth noting that since the electrical energy proportional to the cube of the flow velocity can be extracted, the convergence and divergence nozzle 19 can be easily installed as shown in FIG. .

Although the situation is the same for wind power generation, whether or not it is possible to install a convergence and divergence nozzle on current wind power generators with ever increasing unit capacity is not feasible when considering typhoons and other factors. Will be judged. For this reason, a method of collecting a large number of small wind power generators into one wind power generation facility has not been taken up as a practical design. On the other hand, tidal current power generation is a great advantage over wind power generation because it can construct a tidal current power generation facility by gathering many small hydroelectric generators, and it is easy to install convergence and divergence nozzles structurally. It is.

In wind power generation, measures against strong winds such as typhoons were indispensable. One of the tidal current power generations that corresponds to a typhoon is a measure against severe waves caused by a typhoon, and the second is a massive tsunami water attack. Destructive waves caused by typhoons are a phenomenon only in the region close to the sea surface, and do not affect the deep region in the sea. Therefore, in the region close to the sea surface, special power generation with typhoon specifications designed with high mechanical strength. It is possible to realistically arrange the unit and arrange the standard generation unit in the region where the water depth is more than a certain level.

The tsunami affects the entire tidal cross section. In the above-mentioned trial calculation example, it was assumed that about 60% of the thrust that should be received by the multihull type tidal power generation facility is thrust received by the turbine in order to extract electric power. When a tsunami strikes, it can detect it and automatically shut off the power line, leaving the generator unloaded, and letting the turbine idle so that a considerable part of the abnormal thrust caused by the tsunami can be released. It is also effective to provide a torque limiter between the turbine and the generator for a momentary surge water flow that cannot be electrically handled, and to provide a means for idling the turbine by mechanical means. Still, the tidal power generation facility, which is based on the hull and is moored on the seabed foundation and has a large hydrodynamic resistance area, will be enormous. This is the most important point in design.

For example, in the case of a tidal current of 2.5 m / s, the output of a power generation panel with an effective depth of 100 m and a width of 50 m is about 100,000 kW, and the vertical load due to the power generation load when the angle is 30 degrees from the seabed of the mooring line is about It is estimated that the total tonnage as a catamaran is about 50,000 tons and stable operation is possible by adding 6000 tons and its own weight. It is a natural energy source that is more efficient than hydropower plants that require huge investment, and we can provide tidal power generation that can be realized at an early stage with the technology and equipment currently available.

DESCRIPTION OF SYMBOLS 1 Power generation panel 2 Holding body 3 Power generation unit 4 Hull 5 Upper structure 6 Mooring line 7 Mooring point 8 Mooring arm 9 Rotating shaft structure 10 Hull tip 11 Sea surface 12 Propulsion pod 13 Thruster 14 Rear power generation panel 15 Case 16 Power generation nacelle 17 Pylon 18 Hydro Turbine 19 Conversion Die Version Nozzle

Claims (7)

  The main body of the facility is a multihull structure in which a plurality of elongated hulls are arranged in parallel and connected to each other at predetermined intervals at the sea. When operating as a power generation facility, power generation with a small single-unit output capacity is within the above-mentioned intervals. One set or two sets of power generation panels with a large number of units mounted are installed at the aforementioned interval between two adjacent hulls. In the case of one set, the suspension is suspended from the vicinity of the buoyancy center in the sea. When suspending as far as possible from the downstream side, taking out the kinetic energy of the tidal current from the power generation unit as electrical energy and using it as electric power for hydrogen production equipment etc. on the facility or submarine power transmission, when moving the facility The power generation panel is moved to the fixed state by pulling it up to the sea of the facility. Pull out the power generation unit from a fixed position and perform the necessary repairs at the repair factory on the facility, or insert and install the newly installed or repaired power generation unit at the predetermined position of the power generation panel Ship-type tidal power generation facility.   The aforementioned power generation unit is configured in a casing having a square, regular hexagonal, etc. cross section toward the tidal current, and a power generation nacelle equipped with a pair of hydro turbines and generators is arranged on the central axis, The convergence divergence nozzle that increases the flow velocity in the water channel along the central axis is configured to be detachable from the power generation panel mechanically and electrically with a one-touch motion by the detachment device. The listed multihull tidal current power generation facility.   The power generation unit according to claim 1, wherein a plurality of sub power generation units that are further downsized from the power generation unit according to claim 2 are assembled and configured in parallel toward the power flow. A shipboard tidal power generation facility.   When suspending a pair of power generation panels between two adjacent hulls, the thrust received from the tidal current during power generation by the power generation panel sinks on the bow side of the facility due to the rotational force generated around the connection point with the facility. The mooring point mooring the two mooring lines stretched from the base of the bottom of the seabed to the left and right in the hull axial direction of the aforementioned facility is located downstream of the power generation panel. The multihull type tidal current power generation facility according to claim 1, wherein pitching due to the rotational force of the facility is suppressed by selecting a position where the downward vertical component cancels the rotational force.   When two sets of power generation panels are suspended at a distance between two hulls adjacent to each other, the hull axis direction of the aforementioned facilities of two mooring lines stretched from the base of one place on the seabed near the buoyancy center of the facility The multihull type tidal current power generation facility according to claim 1, wherein mooring points for mooring the left and right sides of the facility are provided near the buoyancy center of the facility. The support structure overhanging from the hull provides the mooring points for mooring the two mooring lines to the hull as far as possible from left and right to suppress yawing due to the force of turning the hull on the sea surface. the anchor point in the powerful than when directly attached to the hull to increase the horizontal posture restoring force of the hull, or the above support structure is always fixed, Moshiku is accommodated in the form when moving to along the hull The multihull type tidal current power generation facility according to claim 4 , wherein the effective width of the hull can be reduced.   From the bows of the two hulls at the left and right ends, the left side is to the left and the right side is to the right. The multihull type tidal current power generation facility according to claim 1, wherein yawing of the entire facility is suppressed on the bow side.

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