KR101179668B1 - Compressed air storage and electricity generating system connected with offshore wind farm and Compressed air storage tank - Google Patents

Abstract

The present invention relates to a marine wind power generation linked compressed air storage and power generation system and an offshore compressed air storage tank used in the system.
Marine wind power generation linked air storage and power generation system according to the present invention is driven by the electric energy produced by a plurality of wind turbines, wind generators installed on the sea to generate electricity by rotating the windmill by the wind Compressor that sucks air and compresses it. It is used to store compressed air. It is installed within a certain depth of the ocean, and the main tank and main tank are formed with gates through which seawater can flow in and out according to the pressure change of the stored air. It includes a turbine driven by the compressed air discharged from the tank.

Description

Compressed air storage and electricity generating system connected with offshore wind farm and Compressed air storage tank

The present invention relates to an energy storage and power generation system, and more particularly, to a compressed air storage and power generation system for generating electricity by compressing and storing air and then rotating a turbine with compressed air, and a storage tank used in the system. .

Energy storage technology, especially power storage technology, can be divided into three main purposes. The first is to supply electricity without interruption until the power supply is resumed if the power supply is suddenly stopped due to an accident. That is, power is stored in order to operate an uninterruptible power supply (UPS) at the time of power interruption.

The second is to prepare for the case where the supply of electric power is required in a specific time period, and the power storage for load management. That is, as shown in the table of FIG. 1, the power consumption is concentrated at a certain time of day and decreases in the middle of the night, the base supply power, such as nuclear power generation is difficult to control the load during power generation when surplus power is generated when power is generated at night There is no choice but to. Therefore, the surplus power generated by the late-night power generation can be stored to replace the peak power generation during the high-cost generation day, and the energy can be managed efficiently.

Third, the purpose is to improve the output characteristics in connection with the power generation system using renewable energy. The most difficult thing about putting renewables in the public power portfolio is the intermittent nature of renewables. For example, solar and wind power, which is growing at the fastest speed in terms of capacity among the renewable energy technologies currently in operation, cannot be continuously generated and can be supplied only during the sun or wind (see FIG. 2). . In other words, current renewable energies have a problem that they cannot meet their needs during the day when they need the most power.

In this regard, the power storage system is capable of storing renewable power generated at a time other than the maximum load, such as a late night time, in an energy storage device and supplying power to the grid at a time (weekly) when the maximum power is required. In conjunction with, very synergistic effects can be achieved.

Compressed Air Energy Storage (CAES), which compresses and stores air from various power storage systems and drives turbines with this compressed air, is considered to be suitable as a large-capacity power storage device. In particular, considering that pumping power generation, which was a large part of the existing large-scale power storage and power generation, is impossible to further construct due to environmental problems and location, CAES is recognized as the only large capacity power storage device. have.

On the other hand, wind power, which has been spotlighted as renewable energy, is classified into onshore wind power and offshore wind power depending on where the wind power generator is installed. Offshore wind power has better wind volume and quality than land. That is, as shown in Figure 3, assuming the same generation capacity, the height of the hub of the offshore wind turbine is lower than the hub of the onshore wind turbine, the diameter of the rotor is also small. In other words, the facility cost for the same power generation means that the offshore wind power is small, and on the contrary, when the same cost is based on the same equipment, it means that more power can be generated at sea than on land.

As described above, in order to use the offshore wind power with good air flow and air quality, it is required to combine the wind power and the compressed air energy storage system to overcome the intermittent power generation problem. Above all, in combining offshore wind power and CAES, development of offshore CAES structure suitable for offshore conditions is required.

The present invention has been made to solve the above problems, marine wind power generation associated compressed air storage and power generation system and the system that can generate air to the turbine after compressing and storing the air at high pressure using the energy obtained by the marine wind power generation The object is to provide a marine compressed air storage tank for use.

Marine wind power generation linked air storage and power generation system according to the present invention for achieving the above object is a plurality of wind turbines installed on the sea to generate electricity by rotating the windmill by the wind, generated by the wind generator Compressor driven by electric energy and compressed by taking in outside air. The main tank and the compressed air discharged from the main tank for storing the compressed air is installed within a certain depth of the ocean and the gate is formed to allow the inflow and outflow of sea water according to the pressure change of the air stored therein It includes a turbine driven by.

According to the present invention, the main tank is further provided with a water depth holding means for positioning the water within a certain depth range of the ocean, the water holding means is preferably using a neutral buoyancy.

In addition, according to an embodiment of the present invention, the water depth maintaining means, the ballast tank is provided in the main tank is provided with a receiving portion for storing sea water and the water inlet and outlet water flows in and out of the receiving portion The buoyancy of the main tank is adjusted by adjusting the amount of seawater contained in the ballast tank.

In an embodiment of the present invention, the main line for introducing the compressed air from the compressor into the main tank, the introduction line for branching from the main line to introduce the compressed air into the blast tank, and the main It is further provided with a valve installed at the branch of the line and the introduction line to determine the path of the compressed air.

The ballast tank may be installed to surround the outer surface of the main tank.

In addition, in the present invention, the main tank may be connected to a rope extending from an anchor fixed to the sea floor so that the displacement of the main tank may be limited.

In addition, in an embodiment of the present invention, the main tank is disposed in plurality a plurality of spaced apart from each other in the sea, the turbine is installed on the ship moving in the sea, the turbine is installed on the ship while moving in the sea, the main tank The turbine may be driven by being connected to a main line connected to the main line.

Meanwhile, the marine compressed air storage tank according to the present invention maintains the main tank within a certain depth range of the ocean by using a main tank and neutral buoyancy disposed within a certain depth range of the ocean to store the air compressed by the compressor. It is provided with a water depth holding means.

In the present invention, by linking the system for generating compressed air to generate a turbine and offshore wind power generation, it is possible to optimize the oversized transmission and distribution facility, which is the weakest point of wind power generation, and to ensure a constant output power quality can be improved.

In addition, in the wind power generation can not control the amount of power generation can not supply electricity suitable for daytime and late-night time, but when the wind power and compressed air storage and power generation device is connected as in the present invention will be optimally generated according to the power consumption by time zone This improves efficiency.

In addition, in the present invention, the compressed air storage tank for linking with the marine wind power is installed at a certain depth of the ocean, and the compressed air is stored using the water pressure, so that the compressed air can be maintained at a constant pressure. The advantage is very economical.

1 is a table showing a load according to time slots for explaining the purpose of electricity storage.
Figure 2 is a table showing the amount of power generation by time to show the intermittent which is a disadvantage of wind power generation.
3 is a table for comparing the onshore wind power and the offshore wind power.
4 is a schematic configuration diagram of a marine wind power generation compressed air storage and power generation system according to an embodiment of the present invention.
FIG. 5 is a schematic cross-sectional view taken along the line V-V of FIG. 4 to explain the marine compressed air storage tank.
6 is a view for explaining a wind power generator.
7 is a view for explaining a power generation process using compressed air.

Hereinafter, with reference to the accompanying drawings, it will be described in more detail with respect to the marine wind power generation compressed air storage and power generation system and marine type compressed air storage tank used in the system according to an embodiment of the present invention.

4 is a schematic configuration diagram of a marine wind power generation compressed air storage and power generation system according to an embodiment of the present invention, Figure 5 is a schematic cross-sectional view of the V-V line of Figure 4, illustrating the marine compressed air storage tank 6 is a view for explaining a wind power generator, and FIG. 7 is a view for explaining a power generation process using compressed air.

4 to 7, the marine wind power generation compressed air storage and power generation system 100 according to an embodiment of the present invention includes a wind power generator 10, a compressor 20, a turbine 30, and a storage tank. 90 is provided.

The wind power generator 10 is for producing electricity by windmills rotated by wind, and is a known device in which various forms are developed. Thus, the wind power generator 10 will be briefly described only with respect to the basic configuration with reference to FIG.

Referring to FIG. 6, the wind generator 10 includes a windmill 11, a main body 12, and a tower 13. The windmill 11 is configured to be freely rotated by the wind, the main body 12 supports the windmill 11 rotatably and produces electricity by using the rotational force of the windmill 11.

That is, the main body 12 is provided with a low speed rotation shaft 14 connected to the windmill 11, the low speed rotation shaft 14 is coupled to a large diameter gear 15, the gear 15 is a small diameter gear Meshes with (16). Thus, the small diameter gear 16 is rotated at high speed compared to the large diameter gear 15, and the high speed rotation shaft 17 coupled to the small gear 16 is rotated very fast compared to the low speed rotation shaft 16. The high speed rotary shaft 17 is connected to the generator 18 to produce electricity. Of course, the inside of the wind turbine body shown in Figure 6 schematically shows the configuration in order to explain the principle of power generation, the actual device is a very complex configuration.

And the tower 13 supports the windmill 11 and the main body 12, the strength and quality of the wind blowing into the windmill is determined according to the height of the tower (13). That is, since the wind strength is proportional to the height of 7 square roots, it is preferable that the windmill 11 is disposed high to improve the power generation efficiency. For example, when the height of the tower 13 is doubled, the wind speed increases by 10%, and the amount of power generated is increased by about 34%.

A plurality of wind turbines 10 having the above-described configuration is generally installed on a large floating body (f) floating on the sea, but a single wind turbine may be floating individually depending on the small floating body.

The compressor 20 is a known device for compressing air at high pressure, and is installed on the floating body f in this embodiment. When the motor 21 rotates, the compressor sucks air and compresses it to high pressure. And when compressing air in the compressor 20, it compresses in multiple stages several times. Although FIG. 7 shows one compressor 20, a plurality of compressors are actually arranged so that the pressure gradually increases as air passes through these compressors. In this embodiment, the air is stored in the storage tank 90 to be described later at a pressure of about 20 to 25 bar by multi-stage compression using the plurality of compressors 20. The storage pressure may of course vary depending on the conditions.

In addition, a cooler 22 is disposed between the compressors 20 to cool the air heated by the compression to increase the compression efficiency in the subsequent compressor. When the compressed air is finally stored in the storage tank 90, the temperature is lowered through the cooler 23.

The storage tank 90 is a place where the compressed air by the compressor 20 is stored, and the main tank 50 where the ocean is installed at a predetermined depth and the main tank 50 can be maintained within a predetermined depth range. A water depth holding means is provided.

The main tank 50 is made of a high strength and heavy material such as steel, for example, and a space 51 for storing compressed air is formed therein. And one side of the main tank 50 is formed with a gate 52 for the inflow and outflow of sea water. The gate 52 may be provided to be opened and closed, but in this embodiment, it is always kept open.

That is, the main tank 50 is installed at the predetermined depth, for example, 200 m depth, the main tank 50, the water pressure is approximately 20 bar. Therefore, when the air is initially filled with water in the main tank 50 and compressed air from the compressor 20 in a state of being placed at a predetermined depth, the main tank 50 is injected with a pressure slightly higher than 20 bar to the main air. The seawater inside the tank 50 will be discharged, and if the air pressure is adjusted at a certain moment, the water pressure and the air pressure are in equilibrium with each other so that the compressed air can be stored in the main tank 50 completely.

When the compressed air is partially discharged from the main tank 50 to lower the air pressure, seawater is introduced through the gate to compress the air again, and thus, the air pressure in the main tank 50 can be always maintained at 20 bar. That is, until the air is completely discharged in the main tank 50, the air pressure of the compressed air is to maintain a constant pressure by the water pressure.

Turbine can operate efficiently above a certain pressure and generate electricity. When the air is stored in a transformer type, the air in the storage tank can be used only from the maximum pressure to the above-mentioned constant pressure, and the pressure in the storage tank is below the predetermined pressure. It is inefficient because if it falls, the air must be compressed again.

However, in the present invention, since the pressure of the compressed air is maintained at a constant pressure (for example, 20 bar) by the sea water, the turbine can be operated until all the air stored in the main tank 50 is exhausted.

And the upper side of the main tank 50 is connected between the compressor 20 and the main tank 50, the main line 53 through which the compressed air flows is installed, the main tank 50 except the gate 52 And remain sealed.

On the other hand, as described above, in order for the pressure in the main tank 50 to maintain a constant pressure, the main tank 50 should be maintained at a predetermined depth. In the present invention, the main tank 50 is provided with a water depth maintaining means to maintain a constant depth.

In this embodiment, the water depth holding means uses neutral buoyancy, and more specifically, the ballast tank 60 is employed as the water depth holding means. The ballast tank 60 is disposed to surround the main tank 50, and the receiving portion 61 to be filled with sea water is formed between the main tank 50. In addition, the ballast tank 60 is provided with a plurality of water passages 62 through which seawater may flow into and out of the accommodation portion 61.

In addition, an introduction line 63 may be connected to the upper side of the ballast tank 60 to introduce compressed air into the receiving portion 61. The introduction line 63 branches from the main line 53, and a valve 70 is installed between the introduction line 63 and the main line 53. The air compressed from the compressor 20 by the valve 70 is selectively injected into either the space 51 of the main tank 50 or the receiving portion 61 of the ballast tank 60. In addition, according to the exemplary embodiment, a valve through which compressed air may be injected from the space 51 of the main tank 50 to the accommodation portion 61 of the ballast tank 60 may be employed.

By adjusting the amount of seawater in the ballast tank 60 by using compressed air, the density of the entire storage tank 90 is made equal to the density of the seawater so that the area where the storage tank 90 is disposed is equal to the density of the seawater. To maintain a certain depth.

For example, when most of the main tank 50 is filled with compressed air, the density of the entire storage tank 90 is lowered, so that the storage tank 90 may rise due to buoyancy. Therefore, in this case, the seawater is introduced into the receiving portion 61 through the water passage 62, thereby increasing the density of the storage tank 90 and maintaining the water depth of the storage tank 90 constant. That is, when the air pressure of the accommodating part 61 discharges the compressed air in the accommodating part 61 through the introduction line 63 while the water pressure is in equilibrium, the seawater may flow into the accommodating part 61 while the pressure decreases. have.

Conversely, if the air in the main tank 50 consumes a lot of seawater is filled in the main tank 50 by the hydraulic pressure, in this case the density of the storage tank 90 is increased so that the storage tank 90 sinks Can be. Therefore, the seawater is discharged from the receiving portion 61 of the ballast tank 60 through the water inlet 62 so that the storage tank 90 maintains a certain depth by lowering the density of the entire storage tank 90. To this end, the compressed air having a pressure higher than the hydraulic pressure may be injected into the accommodation part 61 through the introduction line 63.

As described above, in the present invention, the main tank 50 can be maintained at a constant depth by using the ballast tank 60, thereby maintaining the pressure of the compressed air in the main tank 50 at a constant pressure. Can be.

In addition, the storage tank 90 may be moved by currents or the like, and may constrain the storage tank 90 with an anchor (not shown) to limit the displacement. Of course, in another embodiment of the present invention can be used as a means for maintaining the depth of the storage tank 90 by installing a rigid anchor on the seabed and connected to the storage tank 90. However, in the present embodiment, the ballast tank is used as the water depth holding means, and the anchor is used for the purpose of preventing the storage tank from moving beyond a certain range by current.

On the other hand, the turbine 30 is installed on the floating body f and is operated by the compressed air discharged from the storage tank 90. That is, compressed air is mixed with fuel in a combustor (not shown) and combusted, and this combustion gas rotates a turbine. When the turbine 30 is rotated to produce electricity in the generator 40 is connected to the turbine.

In this embodiment, since the storage tank is composed of a constant pressure type and the pressure is not as high as 20 bar, only one low-pressure turbine needs to be driven. In other words, when the storage tank is configured as a transformer type, the turbine is also inefficient because the high pressure turbine and the low pressure turbine must be operated together.

Although FIG. 7 shows that the turbine 30 is fixedly installed, the turbine 30 does not have to be fixed on the floating body f. As shown in FIG. 4, the turbine 30 is installed on the ship s. And may be used as a mobile.

That is, as shown in Figure 4, if a large number of floats (f) is provided a large-scale wind farm, the turbine 30 may be installed on the ship while generating power. That is, the main line 53 of the storage tank 90 may be connected to the turbine 30 side to generate electricity. When electricity is produced in the generator 40 connected to the turbine 30 is transmitted to the land via a cable (not shown).

Hereinafter, a description will be given of a power generation process by the marine wind power generation linked air storage and power generation system 100 having the above configuration.

Power generated from the wind turbine 10 supplies power to the motor 21 connected to the compressor 20, and the motor 21 rotates to operate the compressor 20. The compressor 20 compresses air into the storage tank 90, and the final air pressure is about 20 bar as described above. Air is compressed to a target pressure while passing through the plurality of compressors 20 and the cooler 22 between the compressors and finally stored in the storage tank 90.

In the storage tank 90, as compressed air is injected, seawater is discharged through the gate 52. Finally, compressed air is preserved in the storage tank 90 while the pressure of the seawater and the pressure of the compressed air are balanced.

When compressed air is discharged along the main line 53 for power generation, the seawater flows through the gate 52 and pressurizes the decompressed air again so that the air in the storage tank 90 maintains a constant pressure state.

When the compressed air stored in the storage tank 90 is discharged, the compressed air is not immediately introduced into the turbine, but through a heat exchanger 35.

Compressed air through the heat exchanger (35) is introduced into the turbine (30) and burned together with the fuel supplied separately to rotate the turbine, and the burned gas passes through the heat exchanger (35) and is then discharged.

Subsequently, since the compressed air discharged from the storage tank 90 receives heat from the high temperature combustion gas in the heat exchanger 35, it is preheated before being introduced into the turbine 30 to improve power generation efficiency. That is, the first compressed air discharged from the storage tank 90 passes through the heat exchanger 35 but is introduced into the turbine without being preheated because it does not receive heat, but the compressed air subsequently introduced into the turbine Heat exchange with the gas after combustion and preheating.

As the turbine operates, the generator 40 connected with the turbine produces power.

Marine wind power generation linked air storage and power generation system configured as described above has the following advantages as compared to the case of wind power generation only.

That is, in the case of wind power generation, the output change of the wind power generator is severe according to the change of the wind volume and the wind speed. Accordingly, in the case of a large-scale complex, a large-scale complex causes a problem of the power system, and thus requires a large-scale transmission and distribution facility. However, when linked with a system that stores compressed air and generates it as a turbine, it is possible to optimize transmission and distribution facilities, and to guarantee a constant output, thereby improving the quality of power.

In addition, it is impossible to control the amount of power generated in wind power generation, so it is not possible to supply electricity for daytime and midnight hours. However, when combined with compressed air storage and power generation equipment, the power generation can be optimally generated according to power consumption according to time zones.

In addition, in the present invention, the compressed air storage tank for linking with the marine wind power is installed at a certain depth of the ocean, and the compressed air is stored using the water pressure, so that the compressed air can be maintained at a constant pressure. The advantage is very economical.

In addition, an embodiment of the present invention provides an optimal facility for linking with the marine wind power, such as by installing a turbine in a boat to operate mobile.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation and that those skilled in the art will recognize that various modifications and equivalent arrangements may be made therein. It will be possible. Accordingly, the true scope of protection of the present invention should be determined only by the appended claims.

100 ... Offshore wind power generation compressed air storage and power generation system
10 ... wind turbines 20 ... compressors
30 ... turbine 40 ... generator
50 ... main tank 60 ... ballast tank
70 ... valves 90 ... marine compressed air storage tanks

Claims (13)

A plurality of wind turbines installed on the sea to generate electricity by rotating the windmill by the wind;
A compressor driven by the electric energy generated by the wind turbine and sucking and compressing external air;
A main tank for storing the compressed air, the main tank being installed within a predetermined depth of the ocean and having a gate through which seawater can flow in and out according to a pressure change of air stored therein; And
And a turbine driven by the compressed air discharged from the main tank.
It is further provided with a water depth holding means for positioning the main tank within a certain depth range of the ocean,
The water depth holding means is provided in the main tank and the ballast tank is formed with a receiving portion for storing sea water and a water inlet and outflow of the sea water from the receiving portion,
The buoyancy of the main tank is adjusted by adjusting the amount of seawater contained in the ballast tank,
A main line for introducing air compressed by the compressor into the main tank;
An introduction line branching from the main line to introduce the compressed air into the ballast tank,
Offshore wind power generation linked compressed air storage and power generation system characterized in that it further comprises a valve installed at the branch point of the main line and the introduction line to determine the path of the compressed air. delete delete delete delete delete The method of claim 1,
The ballast tank is marine wind power generation linked compressed air storage and power generation system characterized in that it is installed surrounding the outer surface of the main tank. The method of claim 1,
The main tank is connected to the rope extending from the anchor is fixed to the seabed connected to the offshore wind power generation compressed air storage and power generation system characterized in that the displacement is limited. A plurality of wind turbines installed on the sea to generate electricity by rotating the windmill by the wind;
A compressor driven by the electric energy generated by the wind turbine and sucking and compressing external air;
A main tank for storing the compressed air, the main tank being installed within a predetermined depth of the ocean and having a gate through which seawater can flow in and out according to a pressure change of air stored therein; And
And a turbine driven by the compressed air discharged from the main tank.
The main tank is disposed in plurality at a distance from the sea,
The turbine is installed on a ship moving at sea,
The ship with the turbine installed is connected to the main line connected to the main tank while moving in the offshore wind power generation linked air storage and power generation system, characterized in that for driving the turbine. A main tank disposed within a certain depth range of the ocean to store the air compressed by the compressor, and having a gate through which seawater flows in and out according to a pressure change of air stored therein; And
And a water depth maintaining means for maintaining the main tank within a predetermined depth range of the ocean using neutral buoyancy.
The water depth holding means is provided in the main tank and the ballast tank is formed with a receiving portion for storing sea water and a water inlet and outflow of the sea water from the receiving portion,
The buoyancy of the main tank is adjusted by adjusting the amount of seawater contained in the ballast tank,
A main line for introducing air compressed by the compressor into the main tank;
An introduction line branching from the main line to introduce the compressed air into the ballast tank,
The marine compressed air storage tank further comprises a valve which is installed at the branch point of the main line and the introduction line to determine the path of the compressed air. delete delete The method of claim 10,
The ballast tank is a marine compressed air storage tank, characterized in that installed to surround the outer surface of the main tank.

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