WO2017181433A1

WO2017181433A1 - Tidal stream generator and stream guiding cover thereof

Info

Publication number: WO2017181433A1
Application number: PCT/CN2016/080084
Authority: WO
Inventors: 林东; 徐虔诚
Original assignee: 杭州林东新能源科技股份有限公司
Priority date: 2016-04-22
Filing date: 2016-04-22
Publication date: 2017-10-26

Abstract

A tidal stream generator and a stream guiding cover thereof are provided. The tidal stream generator comprises a frame, at least one rotary shaft (4), at least one driving unit (6), at least one horizontal axis hydrogenerator (3), and at least one stream guiding cover (5). The rotary shaft (4) is rotatably disposed on the frame. The driving unit (6) is disposed on the surface of the water, and is connected to the rotary shaft (4) to drive the rotary shaft (4) to rotate. The horizontal axis hydrogenerator (3) is fixed on the rotary shaft (4). The stream guiding cover (5) is fixed on the frame, and comprises two water guiding portions (51) and a mid-portion (52). The mid-portion (52) is located between the two water guiding portions (51). An axis (X1) of the rotary shaft (4) and a central axis (X2) of the horizontal axis hydrogenerator (3) intersect at a central point (C). The distance between any point on an inner surface (521) of the mid-portion (52) and the central point (C) is a first distance (S1). An endpoint of a blade (31) of the horizontal axis hydrogenerator (3) farthest from the central point (C) is a farthest endpoint (E). The distance between the farthest endpoint (E) and the central point (C) is a second distance (S2). The first distance (S1) is greater than the second distance (S2). Cross-sections (S) of the mid-portion (52) facing the two ends of the two water guiding portions (51) respectively are round. A radius (R) of the cross sections (S) is slightly greater than a distance between the farthest endpoint (E) and the central axis (X2).

Description

Tidal power generation device and its shroud

Technical field

The invention relates to a power generating device, in particular to a tidal current power generating device and a shroud thereof.

Background technique

Ocean energy (including tidal energy, tidal energy, wave energy, ocean current energy) refers to the energy of seawater flow. As a renewable energy source, it has abundant reserves and wide distribution, and has excellent development prospects and value. The way of utilizing ocean energy is mainly power generation. Its working principle is similar to that of wind power generation, that is, the energy of seawater is converted into electric energy through an energy conversion device. Specifically, first, seawater impacts the turbine, which converts the energy of the water stream into rotational mechanical energy, and then the turbine drives the generator to generate electricity through the mechanical transmission system, and finally converts it into electrical energy.

Nowadays, energy is increasingly in short supply, the greenhouse effect is becoming more and more serious, and energy needs to be low-carbon. Therefore, clean energy such as wind energy and ocean energy is the future development direction of energy. But now these clean energy power generation equipment, in addition to the more mature use of wind energy, the use of ocean energy is still in its infancy, there is no universal and mature equipment. A small number of existing devices also have problems of inefficiency and the inability of devices to be large-scale.

Due to the complex marine environment and high resistance in the water, the installation of traditional marine power generation devices must be carried out in the sea, which is difficult and costly. In addition, due to the long-term contact of the power generation device with seawater, under the long-term erosion and great impact of seawater, the marine energy power generation device should be repaired or replaced periodically after using it for a period of time. However, the maintenance and replacement of the traditional marine power generation equipment are also carried out in the sea, which is difficult and costly. Even because of the damage of some components, the scrapping of the entire marine energy-generating device is one of the important reasons for the high cost of the marine energy-generating device, and it is also a direct cause of the large-scale, commercial operation of the existing marine energy-generating device. the reason.

Especially for horizontal-axis hydro-generators, the maintenance of horizontal-axis hydro-generators is more difficult and costly because all of their equipment (including blades and generators) are underwater. Therefore, even if the horizontal axis hydro-generator has higher power generation efficiency than the vertical-axis hydro-generator, the horizontal-axis hydro-generator cannot be commercialized. However, current technicians in the field of ocean power generation have neglected improvements in the way they install and maintain.

In addition, it is power generation by the tide of the ocean. With the tide and the tide, the direction of the trend will change. Most of the traditional horizontal axis hydro-generators are not able to rotate, resulting in tidal energy generators that can only use high tide or low tide to generate electricity, and the power generation efficiency is extremely low. In order to make full use of the energy generated by high tide and low tide, the prior art personnel choose to install two power generation systems. The impeller of one power generation system is oriented toward the high tide direction, and the impeller of the other power generation system is oriented toward the ebb tide direction. Although it seems to be high tide and low tide The energy generated is fully utilized, but at high tides or low tides, there will always be a set of power generation systems idle. The addition of a power generation system doubles the production cost, and the increase in power generated is far less than the increase in cost, which greatly limits the promotion and application of tidal energy power generation devices.

It should be noted that the tide speeds of high tide and low tide are not constant. When the generator is installed, once the generator is selected, its load is determined. However, the speed of the tidal current is not constant, so the amount of power generation is not constant. In order to save costs and be technically limited, existing tidal current power generation devices can only carry a power generation load below a certain water flow speed, whether it is a horizontal axis hydro-generator or a vertical-axis hydro-generator. Once the water flow rate increases and the power generation exceeds the load, the generator can be easily damaged by overloading. Therefore, in order to prolong the working life of the generator, the conventional tidal energy generating device completely cuts off the water flow once the tidal current exceeds a certain speed, so that the generator stops working, and the power generation efficiency is greatly reduced.

A current tidal energy power generation device draws on the design of a wind energy generator, and adjusts the load of the power generation device by means of pitching. When the water flow speed is large, the blade angle of attack is reduced by the adjusting device; when the water flow speed is small, the blade angle of attack is increased by the adjusting device. However, this design has a lot of drawbacks. Unlike the environment in which wind energy generators are used, horizontal-axis hydro-generators are used in water and are subject to much greater resistance than wind-power generators. Moreover, since the blade angle of the horizontal axis hydro-generator is adjusted, the rotating mechanism is entirely located in the water, and to achieve the rotation of the blade angle, it is necessary to accurately design the tightness between the components of the blade. If the connection is very tight and the friction is too large, it is difficult to adjust the angle of the water surface of the blade, which causes the adjustment device to fail to perform the adjustment effect. In this case, the power generation device cannot improve the efficiency when the water flow is too small, and the generator cannot be truly protected when the water flow is too large. If the connection is too loose, the friction is too small, although it can be easily adjusted, there is a serious problem of loss of sealing. In this way, the water flow will be poured into the interior of the hydro-generator, causing damage to the entire hydro-generator, the maintenance rate is greatly improved, and the cost is greatly increased. Moreover, the turbine generator has several blades to install several rotating mechanisms and control mechanisms, and its cost and technical difficulty increase sharply.

Summary of the invention

In order to overcome at least one of the deficiencies in the prior art, the present invention provides a tidal current power generating device and a shroud thereof.

In order to achieve the above object, the present invention provides a tidal energy power generating apparatus including a frame, at least one rotating shaft, at least one driving unit, at least one horizontal-axis hydro-generator, and at least one shroud. The rotating shaft is rotatably disposed on the frame, the rotating shaft has an axis, and the direction of the axis is perpendicular to the horizontal plane. The drive unit is located on the water surface and is connected to the rotating shaft to drive the rotating shaft. At least one horizontal axis hydro-generator is fixed to the rotating shaft, the horizontal-axis hydro-generator includes blades and a generator, and the horizontal-axis hydro-generator has a central axis, and the direction of the central axis is parallel to the horizontal plane. At least one shroud is fixed to the frame, and the shroud includes two The water guiding portion and the intermediate portion are located between the two water guiding portions. Wherein, the intersection of the axis of the rotating shaft and the central axis of the horizontal axis hydro-generator is a center point, and the distance between any point on the inner surface of the middle portion to the center point is the first distance, and the blade is farthest from the center point. One end point is the farthest point, and the distance between the farth point to the center point is a second distance, and the first distance is greater than the second distance. The intermediate portion faces the two water guiding portions respectively, and the cross section of the two water guiding portions is circular. The plane of the cross section is perpendicular to the horizontal plane and perpendicular to the water flow direction, and the radius of the cross section is slightly larger than the shortest distance between the most distal point and the central axis. .

In an embodiment of the invention, the distance between any point on the inner surface of the intermediate portion to the center point is equal.

In an embodiment of the invention, the distance between any point on the inner surface of the intermediate portion to the center point is slightly greater than the second distance.

In an embodiment of the invention, a cross section of each of the water guiding portions away from the intermediate portion has a rectangular cross section, and a cross section of each of the water guiding portions facing the intermediate portion has a circular cross section, a circular cross section and a rectangular cross section. Both are perpendicular to the horizontal plane and perpendicular to the direction of the water flow, and the area of the circular cross section is smaller than the area of the rectangular cross section.

In an embodiment of the invention, the frame includes an outer frame and at least one inner frame, the inner frame being detachably disposed within the outer frame.

In an embodiment of the invention, at least two horizontal axis hydro-generators are mounted on a mounting shaft and aligned in a direction perpendicular to the horizontal plane within the same inner frame.

In an embodiment of the invention, the number of inner frames is at least three.

According to another aspect of the present invention, the present invention also provides a shroud for use in a tidal energy power generating device, the tidal current power generating device comprising at least one horizontal axis hydro-generator and at least one rotating shaft, and the horizontal shaft hydroelectric generating The machine is fixed to the rotating shaft, the rotating shaft has an axis, the direction of the axis is perpendicular to the horizontal plane, the horizontal axis hydro-generator comprises a blade and a generator, the horizontal axis hydro-generator has a central axis, and the direction of the central axis is parallel to the horizontal plane, wherein The shroud includes two water guiding portions and an intermediate portion, and the intermediate portion is located between the two water guiding portions. The intersection of the axis of the shaft and the central axis of the horizontal axis hydro-generator is the center point, and the distance between any point on the inner surface of the middle portion to the center point is the first distance, and the end point of the blade farthest from the center point The farthest point, the distance between the farthest point and the center point is a second distance, the first distance is greater than the second distance; the cross section of the middle portion facing the two water guiding portions respectively is circular, the cross section The plane is perpendicular to the horizontal plane and perpendicular to the direction of the water flow, and the radius of the cross section is slightly larger than the distance between the most distal point and the central axis.

In an embodiment of the invention, the shroud is of an asymmetrical structure.

In summary, the tidal current power generating device provided by the present invention concentrates the water flow to the horizontal axis hydro-generator by providing a shroud, so that the blades of the horizontal-axis hydro-generator are more stressed and rotate faster. Improve power generation efficiency. By setting the rotating shaft, the load of the generator is innovatively adjusted by changing the orientation of the entire horizontal axis generator instead of changing the water angle of the blade separately, so that the generator can always ensure normal power generation within a safe load regardless of the water flow speed. , greatly improving the efficiency of power generation. In addition, by providing a rotatable shaft, the blades of the horizontal axis hydro-generator can always face the water flow regardless of the high tide or the low tide, thereby ensuring the maximum power generation. By setting a specific size of the shroud to ensure that all the water flowing through the power generating unit is gathered to the rushing blade, the "pressure difference" between the upstream water level and the downstream water level is fully utilized, thereby greatly improving the power generation efficiency. The shroud of the present invention limits the flow of water from flowing directly out of the gap between the shroud and the rotating area of the blade to ensure a higher throughput.

In addition, the present invention provides a detachable inner frame and an outer frame, so that the power generating device can be modularly assembled and replaced on the water surface, greatly reducing maintenance and installation costs, and overcoming the commercialization and large-scale of the conventional tidal energy generating device. The problem.

And, at least three horizontal-axis hydro-generators are arranged in a direction perpendicular to the horizontal plane, and at least two horizontal-axis hydro-generators are arranged in a direction parallel to the horizontal plane, so that the hydro-generator realizes a matrix row Cloth, making full use of the horizontal and vertical tidal currents of the entire sea area, greatly improving power generation efficiency.

Further, in the shroud provided in the embodiment of the present invention, the cross-sectional area of the two ends is larger than the cross-sectional area of the intermediate portion, which has a better function of guiding and collecting, and increases the pressure against the blade. Greatly improve power generation efficiency.

In particular, by setting the shroud to an asymmetrical structure, it is ensured that all currents can be correctly directed to the hydro-generator by the shroud, whether it is high or low tide, thereby maximizing the use of water flow for power generation and power generation. effectiveness.

The above and other objects, features, and advantages of the present invention will become more apparent and understood by the appended claims appended claims

DRAWINGS

1 is a schematic view showing the assembly of a tidal current power generating device according to a first embodiment of the present invention.

2 is a top plan view of a tidal current power generating apparatus according to a first embodiment of the present invention.

3 is a perspective view of a shroud and a horizontal axis hydro-generator provided in accordance with a first embodiment of the present invention.

4 is a side perspective view of a shroud and a horizontal axis hydro-generator provided in accordance with a first embodiment of the present invention.

Figure 5 is a top cross-sectional view of a shroud and a horizontal axis hydro-generator provided in accordance with a first embodiment of the present invention.

Figure 6 is a schematic view of Figure 5 after removal of the shroud.

Figure 7 is a front elevational view of a shroud and a horizontal axis hydro-generator provided in accordance with a first embodiment of the present invention.

Figure 8 is a schematic illustration of a shroud provided in accordance with a second embodiment of the present invention.

detailed description

1 is a schematic view showing the assembly of a tidal current power generating device according to a first embodiment of the present invention. 2 is a top plan view of a tidal current power generating apparatus according to a first embodiment of the present invention. Please refer to Figure 1 and Figure 2 together. The tidal current power generating apparatus provided in the first embodiment of the present invention includes a frame, at least one horizontal-axis hydro-generator 3, at least one rotating shaft 4, at least one shroud 5, and a driving unit 6. The shroud 5 is provided corresponding to the horizontal axis hydro-generator 3.

In the present embodiment, the frame 10 includes an outer frame 1 and at least one inner frame 2, and at least one inner frame 2 is detachably disposed within the outer frame 1. The outer frame 1 can be welded from a steel material. In the present embodiment, the outer frame 1 may have a plurality of fixed piles 11. The fixed pile 11 is formed by pouring concrete in the outer casing. The outer frame 1 is fixed to the sea floor F by piling. In the present embodiment, the outer frame 1 also has a plurality of reduced water flow resistance structures 12. A plurality of reduced water flow resistance structures 12 are located on the water-facing side of the outer frame 1. By setting the water flow resistance structure 12 to the water-facing side of the outer frame 1, the area of the outer casing of the outer frame 1 (hereinafter, the fixed pile 11 is formed here) subjected to the hydraulic impact is greatly reduced, and the force is greatly increased. The stability of the fixed pile 11 formed subsequently. As shown in FIG. 2, the reduced water flow resistance structure 12 is located at the uppermost and lowermost sides of the outer frame 1. In the present embodiment, the cross section of the reduced water flow resistance structure 12 is a triangle. However, the present invention does not limit the specific shape and structure of the water flow resistance structure 12. In other embodiments, the reduced water flow resistance structure can be fabricated as a streamlined type.

In the embodiment, the inner frame 2 can be provided with a hook (not shown), and the outer frame 1 can be provided with a card slot (not shown). The inner frame 2 is embedded by the mutual engagement of the hook and the card slot. Go inside the outer frame 1. However, the present invention does not limit the manner of fixing between the inner frame 2 and the outer frame 1. The present invention is not limited to the specific number of the inner frames 2. Preferably, the number of inner frames 2 is greater than or equal to three. In practical applications, the number of inner frames 2 can be as many as 12 or 14. As shown in FIG. 1, a plurality of inner frames 2 are arranged in a direction parallel to the horizontal plane P, thereby realizing the horizontal expansion of the tidal current power generating device, greatly improving the utilization of tidal energy, and breaking through the existing tidal energy generating device. The drawbacks of achieving scale.

At least one of the rotating shafts 4 is rotatably disposed to the inner frame 2 of the frame 10. The present invention does not limit the number of the rotating shafts 4 in any way. The rotating shaft 4 has an axis X1, and the direction of the axis X1 is perpendicular to the horizontal plane P. Yu Ben In the embodiment, at least two horizontal axis hydro-generators 3 are fixed to one of the rotating shafts 4 and arranged in the same inner frame 2 in a direction D1 perpendicular to the horizontal plane P. As seen from the direction shown in Fig. 1, at least two horizontal axis hydro-generators 3 are longitudinally arranged, thereby realizing the longitudinal expansion of the tidal current power generation device along the depth of the ocean, greatly increasing the power generation, and further overcoming the existing conventional trend. The power generation device cannot achieve the problem of scale.

The sea floor is usually uneven. Due to the presence of rocks, etc., even at a distance of less than ten meters, the difference in the height of the seabed surface is very large. The tidal current power generating device of the present invention can fully utilize the energy in the vertical direction of the ocean, and can flexibly adjust the number of the horizontal axis hydro-generators 3 in the direction D1 according to the distance between the seabed and the water surface. For example, in a place with a relatively high seabed, only two horizontal axis hydro-generators 3 can be fixed on one rotating shaft 4. In a place with a relatively low seabed, four horizontal-axis hydro-generators 3 can be fixed to A shaft 4 is attached. In other words, the number of hydro-generators 3 on each reel does not need to be equal.

In the present invention, an inner frame 2, at least one horizontal axis hydro-generator 3, at least one rotating shaft 4 and one driving unit 6 together form a built-in module 100. In practical applications, at least one horizontal axis hydro-generator 3, at least one rotating shaft 4 and at least one driving unit 6 may be first fixed in an inner frame 2, and then at least one such assembled inner frame 2 is fixed outside. Within the frame 1, a modular installation of the tidal energy generating device is achieved. Specifically, the assembly of the built-in module 100 can be performed on an onshore or offshore platform, and then the built-in module 100 is suspended from the top into the outer frame 1 placed in the sea and the outer frame 1 is fixed, thereby realizing the installation work on the sea surface. , greatly simplify the installation process, reduce installation time and reduce the difficulty of installation in the ocean.

The horizontal axis hydro-generator 3 includes a blade 31 and a generator 32 having a central axis X2 whose direction is parallel to the horizontal plane P. The present invention does not limit the number of the blades 31 of the horizontal axis hydro-generator 3, and each of the horizontal-axis hydro-generators 3 may have two, three or four blades. Since the blades 31 and the generator 32 of the horizontal-axis hydro-generator 3 are all underwater, if the horizontal-axis hydro-generator 3 fails, the conventional tidal power generating device will need to be repaired in the sea. This maintenance is very difficult and costly. However, the tidal current power generating device of the embodiment can directly take out the built-in module 100 from the sea for maintenance or replacement, realize rapid replacement and maintenance of the tidal energy generating device on the sea surface, greatly reduce the maintenance cost, and make the commerce of the tidal power generating device. Realization is achieved.

In the present embodiment, the number of the inner frames 2 is equal to the number of the rotating shafts 4, and the number of the horizontal-axis hydro-generators 3 is larger than the number of the rotating shafts 4. However, the present invention is not limited thereto. In other embodiments, one of the built-in modules 100 may have a plurality of rotating shafts 4 and each of the rotating shafts 4 may have more than two horizontal-axis hydro-generators 3.

Each of the two horizontal-axis hydro-generators 3 mounted on the same rotating shaft 4 rotates in synchronization. The drive unit 6 is coupled to the rotating shaft 4 to drive the rotating shaft 4 to rotate. Since the flow direction of the high tide and the low tide is opposite, no matter which direction the water flow flows in, the blade 31 of the horizontal axis hydro-generator 3 is always directed toward the water flow by the rotation of the rotating shaft 4, thereby improving the utilization of the tidal current energy and improving the power generation efficiency.

In the present invention, the drive unit 6 is located on the water surface. In the prior art, a few horizontal axis hydro-generators can achieve rotation, but the drive units are all located below the water surface, and some even integrate with the generator part. Since the control system, the drive system, the transmission system, the converter system and the power generation system in the prior art are integrated into the blade to form a whole, the volume of the non-blade portion of the existing horizontal-axis hydro-generator is very large, Reduce the performance of electronic components. And the transmission system, including the motor, is very easy to damage and often requires maintenance. The placement of these components under the water surface will greatly increase the difficulty and cost of maintenance. However, the driving unit 6 in the present invention is located above the water surface instead of the water surface, completely solves the above problems, and can greatly reduce the volume of the non-blade portion of the horizontal axis hydro-generator, thereby improving the performance of the electronic components, and finally To achieve the purpose of improving power generation efficiency.

In the present embodiment, the number of the driving units 6 corresponds to the number of the rotating shafts 4. However, the present invention does not limit this. In other embodiments, the control of the two rotating shafts 4 by one driving unit 6 can be realized by a gear mechanism such as a gear. Each of the driving units 6 may include an electric motor and a transmission mechanism, and the transmission mechanism is coupled to one end of the rotating shaft 4, and the electric motor drives the rotating shaft 4 to rotate by the transmission mechanism. However, the present invention is not limited thereto. In other embodiments, the drive unit 6 can include an electric motor and a reducer. Since the existing motor speed is relatively fast, the speed is greatly reduced after passing through the speed reducer, so that the rotation speed and the rotation range of the rotating shaft 4 can be effectively and accurately controlled.

In practical applications, when the water flow flows to the tidal current power generating device in the water flow direction D shown in Fig. 2, the driving unit 6 does not operate. At this time, the blade 31 of the horizontal-axis hydro-generator 3 faces the water flow. When the water flow flows in the opposite direction of the water flow direction D (from top to bottom in FIG. 2) to the tidal current power generating device, the driving unit 6 drives the rotating shaft 4 to rotate, thereby causing the horizontal shaft hydro-generator 3 to rotate 180 degrees. The blade 31 is changed from downward to upward to ensure that the blade 31 of the horizontal axis hydro-generator 3 is always directed toward the water flow. This is especially true for tidal power generation, ensuring maximum power generation.

In particular, the direction of the water flow of the high tide and the low tide in the actual application is not completely parallel, and may not necessarily be perpendicular to the water surface of the horizontal axis hydro-generator 3. Regardless of the direction from which the water flow flows into the horizontal-axis hydro-generator 3, the power generating device of the present invention can control the horizontal-axis hydro-generator 3 to change the orientation through the rotating shaft 4 so that the horizontal-axis hydro-generator 3 is always facing the water flow, thereby maximizing Use tidal energy to the extent and increase power generation.

Moreover, when the actual water flow speed is higher than the rated speed corresponding to the maximum load that the horizontal axis hydro-generator 3 can withstand, at this time, only the rotating shaft 4 is rotated to control the horizontal-axis hydro-generator 3 to rotate away from the water flow direction by an angle. , the load of the horizontal axis hydro-generator 3 can be effectively reduced, and the horizontal-axis hydro-generator 3 is ensured that the horizontal-axis hydro-generator 3 is still not working properly, and the horizontal-axis hydro-generator 3 is still working normally, and the power generation is continuously and stably outputted. . Overcoming the disadvantages of the traditional ocean energy power generation device when the water flow speed is too large, the generator stops working to avoid burning, and the pitch adjustment is not needed, so that the load adjustment of the generator is simpler and more effective. When the actual water flow speed is lower than the rated speed corresponding to the maximum load that the generator 3 can withstand, at this time, it is only necessary to rotate the rotary shaft 4 to control the horizontal shaft hydro-generator 3 so that it rotates in the direction of the water flow direction (ie, the water-facing surface of the blade is perpendicular to In the direction of water flow, the water flow can be utilized to the maximum extent to generate electricity and increase the power generation.

As shown in FIGS. 3 to 7, the shroud 5 has two water guiding portions 51 and one intermediate portion 52. The intermediate portion 52 is located between the two water guiding portions 51. The intersection formed by the axis X1 of the rotating shaft 4 and the central axis X2 of the horizontal-axis hydro-generator 3 is the center point C. The distance between any point on the inner surface 521 of the intermediate portion 52 (point 52a as shown in FIG. 5) to the center point C is the first distance S1, and the end point of each of the blades 31 farthest from the center point C is the most The distance between the far-end point E and the far-end point E to the center point C is the second distance S2, and the first distance S1 is greater than the second distance S2.

In the present embodiment, the distance between any point on the inner surface 521 of the intermediate portion 52 to the center point C is equal, that is, the first distance S1 can be a constant value. Specifically, the movement trajectory of the most distal point E of the blade 31 when the rotary shaft 4 rotates the horizontal axis hydro-generator 3 is a circle as shown in the figure, and the circle is centered on the center point C, the farthest The distance between the endpoint E and the center point C is the radius. The cross section of the intermediate portion 52 (the plane in which the cross section is located is parallel to the horizontal plane P, that is, the section viewed from the direction shown in Fig. 5) is a circular arc shape, and the two circular arc lines shown in Fig. 5 are center points. C is the center of the circle, and the first distance S1 between any point on the inner surface 521 of the intermediate portion 52 to the center point C is the two circumferential lines of the circle made by the radius. In this case, the intermediate portion 52 is a portion of a complete spherical surface after the top and bottom are removed, and the center of the sphere is the center point C.

However, the invention is not limited thereto. In other embodiments, the first distance S1 can be a variable, that is, the first distance S1 between any point on the inner surface 521 of the intermediate portion 52 to the center point C can vary depending on the position of each point. Specifically, in other embodiments, the intermediate portion 52 may still be a curved shape when viewed in the cross-sectional direction, but the curved shape may not be a circular arc shape, and the radius of curvature may be much smaller than the curved shape in the embodiment. Radius of curvature. Or in other embodiments, the intermediate portion 52 may be wavy or polygonal in the cross-sectional direction as long as the first distance S1 is greater than the second distance S2 to ensure that the horizontal axis hydro-generator 3 is changing. The direction can smoothly rotate in the shroud 5.

Preferably, the first distance S1 is slightly larger than the second distance S2, that is, there is only a very small gap between the inner surface 521 of the intermediate portion 52 and the most distal point E of the blade 31, and this gap ensures the horizontal axis water wheel When the generator 3 changes orientation, the farthest point E of the blade 31 does not rub against the inner surface of the intermediate portion 52, while also ensuring that the shroud 5 gathers all the water flow as much as possible in the region where the blade 31 rotates. It is possible that the water flow is not allowed to pass directly through the shroud 5 from the gap without being pushed by the blade 31.

In the present invention, the cross section S of the intermediate portion 52 facing the two ends of the two water guiding portions 51, respectively, is circular, the plane of the cross section S is perpendicular to the horizontal plane P and perpendicular to the water flow direction D, and the radius of the cross section S R is slightly larger than the shortest distance S3 between the most distal point E and the central axis X2 (i.e., a perpendicular from the farthest point E perpendicular to the central axis X2, the length of the perpendicular being the shortest distance S3). The term "slightly larger" as used in the present invention means that the radius R of the cross section S is first greater than the shortest distance S3 such that the intermediate portion 52 does not hinder the rotation of the blade 31, and the area of the cross section S is only the farthest from the blade 31. The area of the circle formed when the end point E is rotated is slightly large so that all of the water flowing toward the blade 31 is almost entirely in the region where the blade 31 is rotated without substantially between the region where the intermediate portion 52 and the blade 31 rotate. The gap flows to the inside of the intermediate portion 52.

The conventional minority horizontal axis hydro-generator 3 can be rotated, but in order to facilitate the rotation of the horizontal-axis hydro-generator 3, the prior art does not consider the optimal size of the shroud 5, but only considers the cross-section S. The radius R is made larger than the second distance S2 between the most distal point E of the blade 31 to the center point C. However, the existing shroud is cylindrical (that is, viewed from a plan view, the left and right sides of the middle portion of the shroud are linear), and since the second distance S2 is certainly greater than the shortest distance S3, this will inevitably lead to a cross section. The radius R of S will be much larger than the shortest distance S3, eventually resulting in a substantial portion of the water flow escaping from the gap between the shroud 5 and the rotating region of the blade 31, i.e., the water flow does not rush toward the blade 31 but directly through the shroud 5 Flow to the downstream. The drawback is that the power generation efficiency will drop significantly, and the performance will be reduced by at least 10%.

In actual use, the water level upstream of the tidal energy generating device and the water level downstream of the tidal energy generating device have a height difference, thereby forming a huge pressure difference. If the shroud 5 is not provided, the differential pressure cannot be effectively utilized for power generation; if most of the water flow passes directly through the shroud 5, the power generation efficiency will not be effectively improved.

In the present embodiment, the cross section 511 of each of the water guiding portions 51 away from the end of the intermediate portion 52 is rectangular, and the end of each of the water guiding portions 51 facing the intermediate portion 52 has a circular cross section, a circular cross section and a rectangular shape. The cross-section 511 is perpendicular to the horizontal plane P and perpendicular to the water flow direction D, the area of the circular cross-section being smaller than the area of the rectangular cross-section. Specifically, each of the water guiding portions 51 has a three-dimensional structure in which one end is rectangular and then transitions to the other end in a circular shape. The area of the circular cross section of the water guiding portion 51 may be approximately equal to the area of the circular cross section S of the intermediate portion.

By providing one end of the water guiding portion 51 as a rectangle, a seamless connection with the end face of the outer frame 1 or the inner frame 2 can be achieved. The shroud used in the existing tidal current power generating device has a circular cross section on the water-facing side. Since the existing frames are all rectangular, a gap is created between the circle and the rectangle during the installation process. If there is no obstacle in the gap, when the current impacts on the horizontal axis hydro-generator, a considerable part of the water will flow from the gap to the horizontal-axis hydro-generator, even hitting the back of the blade, greatly reducing the power generation. If the gap is blocked by the flat plate, the water flow directly hits the flat plate, forming a large stress, which easily damages the structure of the entire frame. In particular, after the plate is blocked, the direction of the water flow changes or even the water flow is disordered, which seriously reduces the utilization of the tidal current energy, thereby reducing the power generation.

By transitioning from a rectangle to a smaller circular area, the water flow channel is narrowed, and the water flow is concentrated to the horizontal axis hydro-generator 3, so that the blade 31 of the horizontal-axis hydro-generator 3 is more stressed and rotates faster. Thereby improving power generation efficiency. In particular, the shroud 5 in this embodiment has a rectangular shape at both ends instead of a rectangular shape at one end, so that the shroud 5 can realize the flow guiding function regardless of the high tide or the low tide.

However, the present invention is not limited thereto, and a structure in which both ends of the water guiding portion are circular may also be applied to the present invention. In the present embodiment, the intermediate portion 52 and the two water guiding portions 51 are respectively coupled together, and by this arrangement, the shroud 5 is formed integrally so that the water flow passes through the inside of the shroud 5 without escaping to the guide. Outside the flow cover 5. However, the present invention is not limited thereto, and it is also within the scope of the present invention to have a gap between the water guiding portion 51 and the intermediate portion 52.

Figure 8 is a schematic illustration of a shroud provided in accordance with a second embodiment of the present invention. The structure and function of the outer frame, the inner frame, the horizontal axis hydro-generator, the rotating shaft and the driving unit are as described in the first embodiment, and are not described herein again. The following only explains the differences.

As shown in Figure 8, each shroud has an asymmetrical structure. Specifically, each shroud also has two water guiding portions 51' and one intermediate portion 52'. Each of the water guiding portions 51' has a three-dimensional structure in which one end is rectangular and then transitions to the other end in a circular shape. However, the intermediate portion 52' is an asymmetrical structure. Specifically, one of the water guiding portions 51' has a first central axis A1, and the other water guiding portion 51' has a second central axis A2. The second central axis A2 and the first central axis A1 form an angle other than zero. .

In actual use, the direction of the tide and the direction of the tide are not the ideal two opposite directions of 180°. Those skilled in the art will easily neglect the deviation of the direction of the high tide and the ebb tide in the actual water, and thus the existing shroud used has a symmetrical structure. There will be a deviation angle between the direction of water flow and the direction of water flow at low tide in different waters, ranging from 3° to 20°. If the tidal current generating device adopts a symmetrical shroud structure, there will be a flow in both the high tide and the low tide, and there will be a guide bush that is completely correctly guided. Therefore, the horizontal axis hydroelectric generator will not be fully fully Use two streams of water to generate electricity. However, by forming between the second central axis A2 and the first central axis A1 The angle is set to be consistent with the angle of deviation between the direction of the tide and the direction of the tide, thus ensuring that all currents are correctly directed by the shroud to the turbine generator, whether it is high or low tide, thereby maximizing the use of water for power generation. Improve power generation efficiency.

The "water flow direction" in the present application refers to the direction of water flow at the time of high tide or low tide, and the other direction in which the water flow hits the barrier is not the direction of the water flow referred to in the present invention. Since any component in the actual application will have a thickness, the "cross section" of the intermediate portion referred to in the present application is actually a "ring", and the "radius of the cross section" referred to in the present application refers to the The inner diameter of the ring.

In summary, the tidal current power generating device provided by the present invention concentrates the water flow to the horizontal axis hydro-generator by providing a shroud, so that the blades of the horizontal-axis hydro-generator are more stressed and rotate faster. Improve power generation efficiency. By setting the rotating shaft, the load of the generator is innovatively adjusted by changing the orientation of the entire horizontal axis generator instead of changing the water angle of the blade separately, so that the generator can always ensure normal power generation within a safe load regardless of the water flow speed. , greatly improving the efficiency of power generation. In addition, by providing a rotatable shaft, the blades of the horizontal axis hydro-generator can always face the water flow regardless of the high tide or the low tide, thereby ensuring the maximum power generation. By setting a specific size of the shroud to ensure that all the water flowing through the power generating unit is gathered to the rushing blade, the "pressure difference" between the upstream water level and the downstream water level is fully utilized, thereby greatly improving the power generation efficiency. The shroud of the present invention limits the flow of water from flowing directly out of the gap between the shroud and the rotating region of the blade to ensure high throughput.

Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the invention, and the invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the scope of the claims.

Claims

A tidal current power generating device, comprising:

frame;

At least one rotating shaft rotatably disposed on the frame, the rotating shaft has an axis, and the direction of the axis is perpendicular to a horizontal plane;

At least one driving unit, located on the water surface, connecting the rotating shaft to drive the rotating shaft to rotate;

At least one horizontal axis hydro-generator coupled to the rotating shaft, the horizontal-axis hydro-generator comprising a blade and a generator, the horizontal-axis hydro-generator having a central axis, the direction of the central axis being parallel to the horizontal plane;

At least one shroud fixed to the frame, the shroud comprising two water guiding portions and an intermediate portion, the intermediate portion being located between the two water guiding portions;

Wherein, the intersection of the axis of the rotating shaft and the central axis of the horizontal axis hydro-generator is a center point, and the distance between any point on the inner surface of the middle portion to the center point is the first distance, and the blade is farthest from the center point. One end point is a farthest point, and a distance between the most distal point and the center point is a second distance, and the first distance is greater than the second distance;

The intermediate portion faces the two ends of the two water guiding portions respectively in a circular cross section, the plane of the cross section is perpendicular to the horizontal plane and perpendicular to the water flow direction, and the radius of the cross section is slightly larger than the farthest point The shortest distance to the central axis.
The tidal current power generating apparatus according to claim 1, wherein a distance from any point on the inner surface of the intermediate portion to the center point is equal.
The tidal current power generating apparatus according to claim 1 or 2, wherein a distance between any point on the inner surface of the intermediate portion to the center point is slightly larger than the second distance.
A tidal current power generating apparatus according to any one of claims 1 to 3, wherein a cross section of each of the water guiding portions away from the intermediate portion has a rectangular cross section, and each of the water guiding portions faces the end of the intermediate portion. The cross section is circular, the circular cross section and the rectangular cross section are both perpendicular to the horizontal plane and perpendicular to the direction of water flow, the area of the circular cross section being smaller than the area of the rectangular cross section.
The tidal current power generating apparatus according to any one of claims 1 to 4, wherein the frame comprises an outer frame and at least one inner frame, and the inner frame is detachably disposed in the outer frame.
The tidal current power generating apparatus according to claim 5, wherein at least two horizontal-axis hydro-generators are fixed to a mounting shaft and arranged in a direction perpendicular to the horizontal plane in the same inner frame.
The tidal current power generating apparatus according to claim 5, wherein the number of the inner frames is at least three.
A shroud for use in a tidal energy generating device, the tidal current generating device comprising at least one horizontal axis hydro-generator and at least one rotating shaft, the horizontal-axis hydro-generator fixed to the rotating shaft The rotating shaft has an axis perpendicular to a horizontal plane, the horizontal axis hydro-generator includes a blade and a generator, the horizontal-axis hydro-generator has a central axis, and a direction of the central axis is parallel to a horizontal plane, wherein The shroud includes:

Two water guiding parts;

The middle portion is located between the two water guiding portions;

Wherein, the intersection of the axis of the rotating shaft and the central axis of the horizontal axis hydro-generator is a center point, and the distance between any point on the inner surface of the middle portion to the center point is the first distance, and the blade is farthest from the center point. One end point is a farthest point, and a distance between the most distal point and the center point is a second distance, and the first distance is greater than the second distance;

The intermediate portion faces the two ends of the two water guiding portions respectively in a circular cross section, the plane of the cross section is perpendicular to the horizontal plane and perpendicular to the water flow direction, and the radius of the cross section is slightly larger than the farthest point The distance to the central axis.
The shroud according to claim 8, wherein the distance between any point on the inner surface of the intermediate portion to the center point is equal.
The shroud according to claim 8 or 9, wherein a cross section of each of the water guiding portions away from the intermediate portion is rectangular, and a cross section of each of the water guiding portions facing the intermediate portion is circular. Both the circular cross section and the rectangular cross section are perpendicular to the horizontal plane and perpendicular to the direction of water flow, the area of the circular cross section being smaller than the area of the rectangular cross section.
A shroud according to claim 8 or claim 9 wherein the distance between any point on the inner surface of the intermediate portion to the center point is slightly greater than the second distance.
The shroud of claim 8 wherein the shroud is of an asymmetrical configuration.