JPH07119485A - Compressed air storage generating system - Google Patents

Abstract

PURPOSE:To perform individual operation of ACC (Automatic Gain Control) when a CAES (compressed air storage generating system) and an ordinary generating system, such as the ACC, are intercoupled. CONSTITUTION:A low pressure generator/motor 6 and a high pressure generator/ motor 11 are driven as a motor and compressed air generated by a low pressure generator 8 and a high pressure generator 13 is stored in an air storage tank 14. Through outflow of the air, high temperature gas is generated by a combustor 15, and a power is generated by the high pressure generator/low pressure generator 11 through drive of a high pressure turbine 9. Further, outflow gas is burnt by a re-combustor 16 and a power is generated by the low pressure generator/motor 6 through drive of a low pressure gas turbine 4. During individual generation by ACC (Automatic Gain Control), a bypass switching valve 19 is switched to a bypass passage 18. Compressed air generated by the low pressure generator 8 is fed to a re-combustor 16 and a power is generated by the low pressure generator/motor 6 serving as a generator through drive of the low pressure gas turbine 4 by means of high temperature gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generation system including a power generation system equipped with an ordinary gas turbine and a compressed air storage power generation system called CAES.

[0002]

2. Description of the Related Art CAES is an air storage tank 102 in which a generator / motor 101 is driven as a motor by electric power generated by a power generation system (not shown) such as thermal power or nuclear power at midnight, as shown in FIG. Compressed air is stored in the air storage tank, while the air storage tank 10 is used at the peak of daytime when electricity consumption is high.
High temperature gas is generated in the combustor 103 by the air flowing out from the No. 2, and the high pressure gas turbine 104 and the like are driven to generate electricity using the generator / motor 101 as a generator. In this specification, a high-efficiency combined power generation, that is, an AC using a gas turbine and a steam turbine as a normal power generation system
Although C is illustrated, a power generation system using only a gas turbine may be used.

[0003]

[Problems to be Solved by the Invention] Conventionally, CAES and AC
It is separate from C, and gas turbine 10
The exhaust heat of the high temperature gas used for power generation by driving the motors 4, 106 is simply used for preheating the compressed air. That is,
The CAES uses the high pressure gas turbine 1 at the time of power generation.
The exhaust gas discharged from 04 is used for driving the low pressure gas turbine 106 after being recombusted in the recombustor 105,
Furthermore, the exhaust gas discharged from the low-pressure gas turbine 106 is operated so as to be used for preheating air in the regenerator 107. In the conventional CAES, the high temperature gas generated from the compressed air is not effectively used, and the net thermal efficiency is as low as about 32%.

Therefore, if the exhaust heat of the high temperature gas used for power generation by driving the gas turbine by CAES is used not only for the power generation of CAES but also by driving the gas turbine again by ACC, it can be used. The power generation system can improve the thermal efficiency as a whole. That is, CAES and AC
A power generation system that combines C and C is desired.

However, in the case of simply combining ACC and CAES, although gas can be sent from CAES to ACC and CAES and ACC can perform power generation operation at the same time, ACC alone cannot operate. That is, while compressed air is flowing from the air storage tank 102, CAES
Although the ACC and the ACC both generate electricity, the ACC cannot operate normally alone after the compressed air flows out from the air storage tank 102. The reason is that compressed air cannot be sent to the ACC side unless it is once stored in the air storage tank 102. If the ACC cannot operate alone after the air stored in the air storage tank 102 is used up, the utilization rate of the power generation facility is significantly reduced.

The present invention is a high-efficiency power generation system in which a normal power generation system such as ACC and CAES are combined, and a normal power generation system such as ACC can operate independently even when CAES is not in an operating state. The purpose is to provide a power generation system.

[0007]

In order to achieve such an object, the present invention provides a low pressure gas turbine, a low pressure generator / motor connected to the low pressure gas turbine via a first clutch, and a low pressure generator / motor. A low pressure compressor connected to the motor via the second clutch, a high pressure gas turbine, a high pressure generator / motor connected to the high pressure gas turbine via a third clutch, and a high pressure generator / motor to the high pressure generator / motor. Of the high pressure compressor connected through the clutch of No. 4, an air storage tank connected to the downstream side through the low pressure compressor and the high pressure compressor in sequence, and an outlet of the air storage tank and an inlet of the high pressure gas turbine. Between the combustor connected between them, the recombustor connected between the outlet of the high pressure gas turbine and the inlet of the low pressure gas turbine, and between the outlet side of the low pressure compressor and the inlet side of the recombustor. Bypass road to connect And a bypass switching valve for opening and closing the fine said bypass passage.

[0008]

Therefore, during air storage, the low-voltage generator / motor and the high-voltage generator / motor drive as motors,
Compressed air obtained from the low pressure compressor and the high pressure compressor is stored in an air storage tank. During CAES power generation, the air stored in the air storage tank is discharged to generate high temperature gas in the combustor, and the high temperature gas drives the high pressure gas turbine to generate electricity using the high pressure generator / motor as a generator. Then, the gas flowing out of the high pressure gas turbine is burned in the recombustor,
The high temperature gas drives a low pressure gas turbine to generate electric power by using a low pressure generator / motor as a generator. Furthermore, during single power generation of a normal gas turbine power generation system such as ACC, the bypass switching valve is switched to the bypass path side, and the compressed air obtained by the low pressure compressor is sent to the recombustor via the bypass path.
High temperature gas is generated in the re-combustor to drive the low pressure gas turbine to generate electricity using the low pressure generator / motor as a generator.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows an embodiment of the compressed air storage power generation system of the present invention. This power generation system is composed of three units of ACC (combined power generation system).
One of them is a CAES unit with ACC.

That is, the first unit is ACC1 and CAE.
Combining S2 and ACC1, low pressure shaft and CAES
Two high-pressure shafts are provided to form a biaxial structure.

The first unit is a steam turbine 3, a low pressure gas turbine 4 connected to the steam turbine 3, and a low pressure generator / motor 6 connected to the low pressure gas turbine 4 via a first clutch 5. A low pressure compressor 8 connected to the low pressure generator / motor 6 via a second clutch 7, a high pressure gas turbine 9, and the high pressure gas turbine 9
High-voltage generator connected to the vehicle via the third clutch 10 /
A motor 11, a high-pressure compressor 13 connected to the high-voltage generator / motor 11 via a fourth clutch 12, and air connected downstream of the low-pressure compressor 8 and the high-pressure compressor 13 in sequence. A storage tank 14, a combustor 15 connected between the outlet of the air storage tank 14 and the inlet of the high-pressure gas turbine 9, and a connection between the outlet of the high-pressure gas turbine 9 and the inlet of the low-pressure gas turbine 4. The re-combustor 16, the exhaust heat recovery boiler 17 connected between the low-pressure gas turbine 4 and the steam turbine 3, and the outlet side of the low-pressure compressor 8 and the inlet side of the re-combustor 16 are connected. A bypass passage 18 and a bypass switching valve 19 that opens and closes the bypass passage 18 are provided.

Here, the low pressure shaft of the ACC 1 includes a steam turbine 3, a low pressure gas turbine 4, a first clutch 5, a low pressure generator / motor 6, a second clutch 7, a low pressure compressor 8 and the like. It consists of Therefore, during CAES air storage, the first clutch 5 is disengaged and the second clutch 7 is engaged, and the generator / motor 6 drives the compressor 8 as a motor to send compressed air to the CAES 2. Also, CA
At the time of ES power generation, the second clutch 7 is disengaged to connect the first clutch 5, and the low-pressure gas turbine 4 is driven by the high-temperature gas generated by the compressed air flowing out from the air storage tank 14 of the CAES 2 to generate a generator / motor. Generate electricity by 6. Furthermore, during the normal operation of ACC1, the ACC1 operates independently. That is, the compressed air obtained in the low-pressure compressor 8 is guided to the bypass passage 18 by the bypass switching valve 19 to generate high temperature gas in the recombustor 16, and the low temperature gas turbine 4 is driven to generate electric power by the generator / motor 6.

The exhaust heat recovery boiler 17 is arranged at the outlet of the low pressure gas turbine 4 and is provided so as to generate steam by the heat of the gas discharged after the low pressure gas turbine 4 is driven to drive the steam turbine 3. ing. Therefore, the steam turbine 3 and the low-pressure gas turbine 4 cooperate to drive the generator / motor 6.

On the other hand, the high pressure shaft of the CAES 2 includes a high pressure gas turbine 9, a third clutch 10, a high pressure generator / motor 11, a fourth clutch 12, and a high pressure compressor 13.
It is composed of a steam turbine 24 and the like. Therefore, at the time of CAES air storage, the third clutch 10 is disengaged and the fourth clutch 12 is connected, and the generator / motor 11
Is driven as a motor, and the compressed air sent from ACC1 is further driven by the high pressure compressor 13 to be sent to the air storage tank side. At the time of CAES power generation, the fourth clutch 12 is disengaged and the third clutch 10 is connected to generate high temperature gas in the combustor 15 using the compressed air flowing out from the air storage tank 14 to drive the high pressure gas turbine 9. Exhaust gas generated by the generator / motor 11 and discharged from the high-pressure gas turbine 9 is sent to the ACC 1. Furthermore, when the ACC operates alone, this CAES does not operate at all.

The intercooler 21 is connected between the low pressure compressor 8 and the high pressure compressor 13. The rear cooler 22 is connected between the high pressure compressor 13 and the air storage tank 14. Therefore, the air is stored in the air storage tank 14 after being compressed and cooled in two steps to reduce the volume.

On the other hand, the high pressure compressor 13 is connected to a steam turbine 24 via a fifth clutch 23. The steam turbine 24 is configured to be driven by steam generated by the heat obtained when the compressed air is cooled by the intermediate cooler 21 and the rear cooler 22. The exhaust heat generated when the compressed air is cooled in this way is effectively used for driving the high-pressure compressor 13 by driving the steam turbine 24.

Further, the air storage tank 14 is provided with opening / closing valves 27 and 28 on the air inlet side and the air outlet side, respectively, so that one of them is opened during air storage and during CAES power generation. ing. The combustor 15 is the air storage tank 1
It is provided so that air such as LNG burns fuel such as LNG to generate high-temperature gas for driving the high-pressure gas turbine 9. In addition, the reburner 16
Is provided to reburn the gas discharged from the high-pressure gas turbine 9 to drive the low-pressure gas turbine 4.

Further, the bypass passage 18 and the bypass switching valve 19 are provided so as to connect or disconnect the ACC1 and the CAES2 by operating the bypass switching valve 19. The bypass passage 18 sends compressed air from the low pressure compressor 8 to CAES2 when CAES2 is coupled to ACC1.
When the CAES 2 is separated from the ACC 1, the compressed air from the low pressure compressor 8 is directly sent to the recombustor 16, and the high temperature gas generated in the recombustor 16 functions to flow into the low pressure gas turbine 4.

The second and third units are each L
A gas turbine 29 driven by a high temperature gas such as NG,
29, generators 30, 30 connected to the gas turbines 29, 29, and steam turbines 31, 31 driven by exhaust heat from the gas turbines 29, 29 and connected to the generators 30, 30 ing. Of these, CAES
The electric power generated in the second unit is used for air storage.

The power generation system configured as described above is
Generate electricity as follows.

First, the air storage operation of CAES2 is shown in FIG.
FIG. 2 (A) will also be described. This CAES air storage consumes very little power at midnight, in this embodiment from 23:00.
It is held at 7 o'clock. In the first unit, the first and third clutches 5 and 10 are disengaged, and the second, fourth and fifth clutches 7, 12, and 23 are connected to connect the low-voltage generator / motor 6 and the high-voltage generator / motor 11 to each other. Is used as a motor, and the bypass switching valve 19 is set to the coupling state of ACC1 and CAES2.

In this state, the second unit is operated to generate electric power, and the operation of the third unit is stopped. Then, the low-voltage generator / motor 6 and the high-voltage generator / motor 11 of the first unit are driven as electric motors by the electric power from the second unit, and the high-pressure compressor 8 and the low-pressure compressor 13 are rotated. The compressed air obtained by the low-pressure compressor 8 is cooled by the intercooler 21, further compressed by the high-pressure compressor 13, and then cooled by the rear cooler 22, and then the air storage tank 14
Store in. At this time, the heat obtained by cooling the intercooler 21 and the rear cooler 22 causes steam to be generated in the boilers 25 and 26, and the steam causes the steam turbine 24
To drive the high pressure compressor 13 in cooperation with the high pressure gas turbine 9.

Next, FIG. 1 shows the time of power generation of CAES2.
(B) will also be described. The CAES power generation is performed at a predetermined time during the day when the power consumption reaches its peak, that is, 7:00 to 14:40 in this embodiment. At this time, the second and fourth clutches 7 and 12 are disengaged, and the first and third clutches 5 and 1 are released.
0 are connected, and the low-voltage generator / motor 6 and the high-voltage generator / motor 6 are connected to the low-pressure gas turbine 4 and the high-pressure gas turbine 9, respectively, and are ready to be used as generators. Further, the bypass switching valve 19 is
1 and CAES2 are kept in a bound state.

In this state, the opening / closing valve 28 is opened to allow compressed air to flow out from the air storage tank 14. Then, the air flowing out from the air storage tank 14 becomes LN in the combustor 15.
G is burned to generate a high-temperature gas, and this high-temperature gas drives the high-pressure gas turbine 9 to drive the high-voltage generator / motor 11 as a generator to generate electricity, and subsequently, the gas flowing out of the high-pressure gas turbine 9 is generated. The high temperature gas re-combusts in the re-combustor 16 and drives the low pressure gas turbine 4 to drive the low pressure generator / motor 6 as a generator to generate electric power.

Steam is generated in the exhaust heat recovery boiler 17 by the exhaust gas flowing out from the low-pressure gas turbine 4,
The steam drives the steam turbine 3 and cooperates with the low pressure gas turbine 4 to drive the low pressure generator / motor 6 as a generator.

Thus, at the peak of power consumption,
Electric power is generated by the low-voltage generator / motor 6 of the first unit ACC1, the high-voltage generator / motor 11 of the CAES2, the generators 30 and 30 of the second and third units, and all the generators.

Next, the single power generation of ACC is shown in FIG.
(C) will also be described. This ACC power generation is performed at a predetermined time after the peak power consumption, that is, 14:36 in this embodiment.
It will be held from 23:00 to 23:00. At this time, the bypass switching valve 1
9 to switch the bypass 18 to the open state,
Separate CAES2 from 1. In ACC1, the first and second clutches 5 and 7 are connected to connect the low pressure gas turbine 4, the low pressure generator / motor 6, and the low pressure compressor 8.

In this state, the compressed air obtained by the low pressure compressor 8 is sent to the recombustor 16 via the bypass passage 18,
The low-pressure gas turbine 4 is driven by the high-temperature gas obtained by the recombustor 16, and the low-pressure generator / motor 6 cooperates with the steam turbine 3.
Drive as a generator to generate electricity.

As described above, even after the peak power consumption, the low-voltage generator / motor 6 of the ACC1 independently generates power in the first unit, and also generates power in the second and third units.

An example of the power balance for each of the above three operating states will be described below with reference to FIG. Since the efficiency of ACC1 decreases when the load is a partial load, it is desirable to perform rated operation. In addition, CAES2 is naturally operated in rated operation because it is operated during power generation peak hours. In the present embodiment, the rated output of ACC of the second and third units is 330 MW, and the rated output of ACC + CAES of the first unit is 778 MW.

First, at the time of storing CAES air, as shown in FIG.
As shown in (A), 330M in the second unit
W power is generated, 300 MW of which is consumed for air storage in the first unit, and eventually 30 MW of electric power is supplied. In addition, at the time of power generation of CAES, as shown in FIG. 2B, power is generated by both ACC and CAES in the first unit to generate 778 MW, and the second and third units are generated.
Each unit generates 330 MW and a total of 1,438 MW. In addition, at the time of ACC power generation, as shown in FIG.
The CC operates independently and generates 329 MW, generating 330 MW in each of the second and third units, for a total of 98
Generates 9 MW.

If four units of the first to fourth ACCs are provided, the total amount of electric power is 330 MW × 4 and 1,320 MW. On the other hand, as in the present embodiment, the CAE is added to the ACC.
According to the three units including the first unit with S installed and the second and third units only with ACC, it is possible to secure a total power amount of 1,438 MW which exceeds four units at the peak of power consumption. In other words, in the present embodiment, the ACC having the output of about 4 + 1/3 units can be realized by 3 units.

The amount of power generated by the power generation system of this embodiment is shown as a daily load pattern in FIG. As shown in FIG. 3 (A), the first unit operates both ACC and CAES at the peak of 7:00 to 14:36 to generate 778 MW of power,
From 14:36 to 23:33 by ACC alone operation
It generates 0 MW and consumes 300 MW from 23:00 to 7:00 by storing air in CAES. The second unit is
It operates at 330 MW all day long. The third unit generates electric power at 330 MW from 7:00 to 23:00.

A total daily load pattern of the first to third units is shown in FIG. 3 (B).

By the way, if the ACC1 and the CAES2 are simply combined, the compressed air will always flow from the ACC1 to the CES.
A unless it goes through the large-capacity air storage tank 14 of AES2
Not sent to CC1. Therefore, although the CAES does not operate (14:36 to 23:00 in the present embodiment), the ACC is required although a considerable amount of power is required to be supplied.
No hot gas can be supplied to 1, and ACC1 cannot operate alone. Therefore, when simply coupling ACC1 and CAES2, the first unit is completely in the stopped state from 14:36 to 23:00 and only the second and third units are operated. As indicated by the dotted line 32 in), the supplied power is drastically reduced to 660 MW. On the other hand, according to the power generation system of this embodiment,
Since the ACC1 can be operated independently even when the CAES2 is stopped, the power generation amount does not drop sharply to 989 MW even when the power consumption exceeds the peak time period.

The thermal efficiency of this example is as follows. First, the thermal efficiency during CAES operation is as follows.

[Equation 1] Further, the thermal efficiency during ACC operation is as follows.

[Equation 2]

As described above, the power generation system of the present embodiment is C
Since the exhaust gas is sent from AES2 to ACC1, its thermal efficiency is high.

The above-described embodiment is an example of the preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention.

[0040]

As is apparent from the above description, in the compressed air storage power generation system of the present invention, the low-pressure generator / motor and the high-voltage generator / motor are driven as motors during air storage, and the low-pressure compressor and high-pressure compressor are operated. Compressed air obtained by the machine is stored in the air storage tank, and during CAES power generation, the air stored in the air storage tank is discharged to generate high temperature gas in the combustor, and the high temperature gas drives the high pressure gas turbine. To generate electricity by using the high-pressure generator / motor as a generator, and then burn the gas flowing out of the high-pressure gas turbine in a recombustor, and drive the low-pressure gas turbine by the high-temperature gas to generate the low-pressure generator / motor. Power as a machine, and further ACC
At the time of independent power generation of the normal power generation system such as the above, the bypass switching valve is switched to the bypass path side, the compressed air obtained by the low pressure compressor is sent to the recombustor through the bypass path, high temperature gas is generated in the recombustor, and low pressure is generated. The gas turbine is driven and the low-voltage generator / motor is used as a generator to generate electricity.
Since the gas used for power generation by AES is used again for power generation by ACC, thermal efficiency can be improved, and even when CAES is not operating, a normal power generation system such as ACC can operate independently, and the power generation amount of the entire system can be improved. Can be increased. In particular, even when the peak power consumption time period is passed in one day, the ACC or the like can be operated independently, so that the power supply amount does not drop sharply.

[Brief description of drawings]

FIG. 1 is a system diagram of an embodiment of a compressed air storage power generation system of the present invention.

2 is a state diagram of the operation of the power generation system of FIG. 1, (A)
Is for CAES air storage, (B) is for CAES power generation,
(C) is during ACC single operation.

FIG. 3 is a load pattern diagram of the power generation system of FIG.
(A) is a load pattern of each unit of the power generation system, and (B) is a load pattern of the entire system.

FIG. 4 is a system diagram of a conventional CAES.

[Explanation of symbols]

 1 ACC 2 CAES 3 Steam Turbine 4 Low Pressure Gas Turbine 5 First Clutch 6 Low Pressure Generator / Motor 7 Second Clutch 8 Low Pressure Compressor 9 High Pressure Gas Turbine 10 Third Clutch 11 High Pressure Generator / Motor 12 Fourth Clutch 13 High-pressure compressor 14 Air storage tank 15 Combustor 16 Recombustor 17 Exhaust heat recovery boiler 18 Bypass path 19 Bypass switching valve

Claims (1)

[Claims] 1. A low pressure gas turbine, a low pressure generator / motor coupled to the low pressure gas turbine via a first clutch, and a low pressure coupled to the low pressure generator / motor via a second clutch. Compressor, high pressure gas turbine, high pressure generator / motor coupled to the high pressure gas turbine via a third clutch, and high pressure compression coupled to the high pressure generator / motor via a fourth clutch Machine, an air storage tank connected to the downstream side of the low pressure compressor and the high pressure compressor in sequence, and a combustor connected between the outlet of the air storage tank and the inlet of the high pressure gas turbine, A recombustor connected between the outlet of the high-pressure gas turbine and the inlet of the low-pressure gas turbine, a bypass passage connecting the outlet side of the low-pressure compressor and the inlet side of the recombustor, and the bypass passage Bypass to open and close A compressed air storage power generation system comprising: a switching valve.