JP2003328779A - Fuel supply system and air-fuel ratio adjusting method for gas turbine and gas turbine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the temperature deviation of fuel gas to be injected from a plurality of combustors. <P>SOLUTION: Each of combustors 20<SB>1</SB>to 20<SB>20</SB>is provided with a sensor 30<SB>1</SB>to measure the premixed flame temperature of each of the combustors 20<SB>1</SB>to 20<SB>20</SB>. The flow rate of the fuel f to be supplied to each combustor is adjusted by adjusting each of flow control valves 10<SB>1</SB>to 10<SB>20</SB>according to the premixed flame temperature of each of the combustors 20<SB>1</SB>to 20<SB>20</SB>. For example, if the premixed flame temperature is higher than the preset temperature, the amount of fuel f to be supplied is decreased and if the premixed flame temperature is lower than the preset temperature, the amount of fuel f to be supplied is increased. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a technique for supplying fuel to a combustor of a gas turbine, and more specifically,
The present invention relates to a fuel supply system for a gas turbine, a fuel-air ratio adjusting method, and a gas turbine, which can reduce temperature deviation of combustion gas injected from a plurality of combustors.

[0002]

2. Description of the Related Art A gas turbine is characterized in that it is relatively small, can obtain a large output, and can be quickly started. Further, the heat of exhaust gas discharged from the gas turbine is recovered by an HRSG (Heat Recovery Steam Generator) to form a gas turbine complex plant, so that the efficiency of the entire plant can be increased. Therefore, in recent thermal power generation, many such gas turbine complex plants are constructed. In particular, in recent years, in order to suppress the generation amount of NOx as much as possible, premixed combustors, in which fuel and air are sufficiently mixed in advance and then burned, have been widely used.

FIG. 9 is an explanatory view showing a fuel supply system in a conventional gas turbine. The gas turbine includes a compressor 940, combustors 920 _{1 to} 920 ₂₀ and a turbine 930. In general, in a gas turbine, the plurality of combustors 920 _{1 to} 920 ₂₀ react the compressed air generated in the compressor 940 with the fuel f to generate high-temperature / high-pressure combustion gas G. Then, the combustion gas G is injected into the turbine 930 to drive the turbine 930. In the conventional gas turbine fuel supply system 900, the flow rate of the fuel f is adjusted to a predetermined pressure by the pressure control valve 902, and then the flow rate thereof is adjusted to a predetermined fuel air ratio by the flow rate control valve 904. Then, the fuel f is supplied to each of the combustors 920 _{1 to} 920 ₂₀ at the same flow rate after being branched after passing through the cutoff valve 906.

[0004]

By the way, the combustor 92
0 by manufacturing tolerances of ₁ etc. and the fuel supply nozzle (not shown), there is a maximum in the possibility of variation of about ± 2% is generated in the fuel-air ratio. However, in the conventional gas turbine fuel supply system 900 (the portion surrounded by the dotted line in the figure), the fuel f is supplied to each of the combustors 920 _{1 to} 920 ₂₀ at the same pressure. The variation of the air ratio could not be changed. As a result, there is a difference of about 40 ° C in the flame temperature, and the NOx generation amount is 10p.
There may be a difference in pm. Further, in the combustor 920 ₁ or the like having a large fuel-air ratio due to the above manufacturing variations, high-cycle oscillating combustion is likely to occur, and the operation of the gas turbine may become unstable. Therefore, the present invention has been made in view of the above, and a fuel supply system and a fuel-air ratio adjusting method of a gas turbine capable of reducing the temperature deviation of combustion gas injected from a plurality of combustors,
Another object of the present invention is to provide a gas turbine.

[0005]

In order to achieve the above object, a fuel supply system for a gas turbine according to a first aspect of the present invention is a gas turbine having a plurality of combustors, the upstream side of at least one of the combustors. A fuel flow rate adjusting means capable of adjusting the flow rate of the fuel supplied to the combustor is provided.

In the fuel supply system of this gas turbine, the flow rate of the fuel supplied to the combustor can be adjusted by the flow rate adjusting valve, the orifice, and other fuel flow rate adjusting means. Therefore, variations in combustion temperature due to manufacturing variations in combustor components such as the combustor inner cylinder, the combustor tail cylinder, and the fuel nozzle (hereinafter collectively referred to as combustor manufacturing variations) are within a predetermined range. Can be suppressed. As a result, even if there is manufacturing variation in each combustor, it is possible to keep the fuel-air ratio constant and reduce variations in premixed flame temperature and combustor internal pressure variation. As a result, it is possible to reduce the amount of NOx generated to the value at the time of design, reduce high cycle oscillatory combustion, and operate the gas turbine stably.

Further, the fuel-air ratio of each combustor can be kept within a predetermined range by the fuel flow rate adjusting means without raising the manufacturing accuracy of each combustor. As a result, even a combustor having manufacturing variations can be used, so that the manufacturing cost of each combustor can be reduced and the yield can be improved. Further, since the combustor can be manufactured even if the manufacturing technology is not so high, it is not necessary to provide sophisticated manufacturing equipment. The fuel flow rate adjusting means may be provided in at least one combustor according to the manufacturing variation of each combustor, and is not necessarily provided in all combustors.

Further, in a gas turbine fuel supply system according to a second aspect of the present invention, in a gas turbine having a plurality of combustors, the flow rate of fuel supplied to the combustors can be adjusted upstream of each combustor. A fuel flow rate adjusting means may be provided. As described above, when the fuel flow rate adjusting means is provided upstream of each combustor, the fuel flow rate supplied to each combustor can be adjusted separately, so that the degree of freedom of adjustment is improved.

A fuel supply system for a gas turbine according to a third aspect of the present invention is the fuel supply system for a gas turbine according to the first or second aspect, wherein the fuel flow rate adjusting means varies the fuel flow rate during fuel supply. It is characterized in that it is a flow rate adjusting valve or other variable flow rate type fuel flow rate adjusting means.

In this gas turbine fuel supply system, the flow rate of the fuel supplied to the combustor can be adjusted by the variable flow rate fuel flow rate adjusting means. You can adjust the ratio. As a result, the gas turbine does not have to be stopped in order to adjust the fuel flow rate, so the fuel-air ratio of each combustor can be easily adjusted, and the gas turbine operating rate can be increased. Also,
It will be easier to handle when automatically controlling the fuel flow rate. Further, even when the fuel supply amount changes due to the load of the gas turbine, the fuel-air ratio of each combustor can be finely adjusted to the optimum range according to the load. This makes it possible to obtain higher NOx reduction and oscillating combustion reduction effects even with respect to load fluctuations.

A fuel supply system for a gas turbine according to a fourth aspect is the fuel supply system for a gas turbine according to the first or second aspect, wherein the fuel flow rate adjusting means is an orifice, a throttle valve, a venturi or other flow rate. It is characterized in that it is a fixed flow rate fuel flow rate adjusting means for changing the fixed type adjusting means to a different flow rate.

When the variable flow rate fuel flow rate adjusting means is used, the flow rate of the fuel once adjusted may change with time even if the flow rate is adjusted to an appropriate flow rate. In this fuel supply system for a gas turbine, the flow rate of the fuel supplied to the combustor is adjusted by changing the fixed flow rate adjusting means such as an orifice or a throttle valve to a different flow rate. Therefore, once the flow rate of the fuel is determined, it is fixed to this flow rate, so that stable operation can be performed while minimizing the fluctuation of the fuel flow rate with the passage of time. Further, since an orifice or the like which is cheaper than the flow rate adjusting valve is used, the manufacturing cost can be suppressed.

A fuel supply system for a gas turbine according to a fifth aspect is the fuel supply system for a gas turbine according to the first or second aspect, wherein the fuel flow rate adjusting means includes an orifice, a throttle valve, a venturi and other flow rates. Fixed type adjusting means, bypass means for bypassing the fixed flow rate adjusting means to supply fuel to the combustor, and either fixed flow rate adjusting means or bypass means for supply to the combustor And a fuel switching means for causing the fuel to flow, and while the fixed flow rate adjusting means is being changed, the fuel is caused to flow through the bypass means to supply the fuel to the combustor.

The fuel supply system for this gas turbine is
The flow rate of the fuel supplied to the combustor is adjusted by the fixed flow rate adjusting means such as an orifice or a throttle valve. During the adjustment, the fixed flow rate adjusting means is bypassed to supply the fuel to the combustor. Therefore, the flow rate of the fuel supplied to the combustor can be adjusted even during operation of the gas turbine. As a result, the fuel-air ratio of each combustor can be easily adjusted, and the gas turbine operating rate can be increased. Further, since the fixed flow rate adjusting means is used, it is possible to minimize the flow rate fluctuation of the fuel with the passage of time and perform stable operation.
Further, since an orifice or the like which is cheaper than the flow rate adjusting valve is used, the manufacturing cost can be suppressed.

A gas turbine according to a sixth aspect includes a compressor for compressing air, a combustor for reacting the air compressed by the compressor with a fuel to generate combustion gas, and the combustor. The fuel supply system according to any one of claims 1 to 5 for supplying fuel, and a turbine driven by the combustion gas generated in the combustor.

Since this gas turbine is equipped with the above fuel supply system, it is possible to suppress variations in combustion temperature due to variations in manufacturing combustors within a predetermined range. As a result, even if there is manufacturing variation in each combustor, it is possible to keep the fuel-air ratio constant and reduce variations in premixed flame temperature and combustor internal pressure variation. As a result, it is possible to reduce the amount of NOx generated to the value at the time of design, reduce high cycle oscillatory combustion, and operate the gas turbine stably. Further, the fuel flow rate adjusting means can keep the fuel-air ratio of each combustor within a predetermined range without raising the manufacturing accuracy of each combustor. As a result, even a combustor with variations in production can be used, and the production cost of the gas turbine can be reduced. Further, since the combustor can be manufactured even if the manufacturing technology is not so high, it is not necessary to provide sophisticated manufacturing equipment.

Further, in the fuel-air ratio adjusting method for a gas turbine according to a seventh aspect of the present invention, in adjusting the fuel-air ratio of a gas turbine having a plurality of combustors, the temperature distribution of the combustor or the combustor internal pressure It is characterized in that the amount of fuel supplied is adjusted according to at least one of the fluctuations.

In this fuel-air ratio adjusting method for a gas turbine, when adjusting the fuel supplied to each combustor to adjust the fuel-air ratio of the gas turbine, the temperature distribution of the combustor or the combustor of the combustor is used as its parameter. At least one of internal pressure fluctuations is used. If the temperature distribution of the combustor having a high correlation with NOx is used as a parameter, the fuel-air ratio of each combustor can be suppressed within a predetermined range with high accuracy. Further, if the combustor internal pressure fluctuation of the combustor highly correlated with the oscillatory combustion is used as a parameter, the fuel-air ratio of each combustor can be suppressed within a predetermined range with high accuracy, and the occurrence of oscillatory combustion can be suppressed quickly. it can. As a result, even if there is manufacturing variation in each combustor, it is possible to keep the fuel-air ratio constant and reduce variations in premixed flame temperature and combustor internal pressure variation. As a result, the amount of NOx generated can be reduced to a value at the time of design, and high cycle oscillatory combustion can be rapidly reduced to stably operate the gas turbine. Further, the fuel flow rate adjusting means can keep the fuel-air ratio of each combustor within a predetermined range without raising the manufacturing accuracy of each combustor. As a result, even a combustor with variations in production can be used, and the production cost of the gas turbine can be reduced.

Further, in the fuel-air ratio adjusting method for a gas turbine according to an eighth aspect, when adjusting the fuel-air ratio of a gas turbine having a plurality of combustors, the flow rate of air supplied to the combustor is adjusted. It is characterized by In this way, by adjusting the flow rate of the air supplied to each combustor, the fuel-air ratio of each combustor can be suppressed within a predetermined range. Can be suppressed within a predetermined range. As a result, even if there is manufacturing variation in each combustor, it is possible to keep the fuel-air ratio constant and reduce variations in premixed flame temperature and combustor internal pressure variation. As a result, it is possible to reduce the amount of NOx generated to the value at the time of design, reduce high cycle oscillatory combustion, and operate the gas turbine stably.

Further, as in the fuel-air ratio adjusting method for a gas turbine according to a ninth aspect, according to the load of the gas turbine, the combustion in which a part of the supplied air is mixed with the combustion gas without being used for combustion. When adjusting the fuel-air ratio of a gas turbine including a plurality of burners, the fuel-air ratio of the combustor may be adjusted by adjusting the amount of air mixed with the combustion gas. When adjusting the fuel-air ratio of a gas turbine including a plurality of combustors having an air flow rate adjusting means capable of adjusting the flow rate of the supplied air, as in the fuel-air ratio adjusting method for a gas turbine according to claim 10. The fuel-air ratio of the combustor may be adjusted by adjusting the air flow rate adjusting means. In the fuel-air ratio adjusting method for these gas turbines, the air flow rate adjusting means already attached to the combustor of the gas turbine or the combustor bypass means for mixing a part of the supplied air with the combustion gas is used. The fuel-air ratio can be adjusted. Therefore, since it is not necessary to provide a new device for adjusting the fuel-air ratio, even the existing gas turbine can easily adjust the fuel-air ratio to increase NOx due to manufacturing variation of the combustor. Can solve such problems.

Further, a method for adjusting a fuel-air ratio of a gas turbine according to an eleventh aspect is the method for adjusting a fuel-air ratio for a gas turbine according to any one of the seventh to tenth aspects, wherein a plurality of combustors are provided. In adjusting the fuel-air ratio of the gas turbine,
It is characterized in that the flow rate of the air supplied to the combustor is adjusted according to at least one of the temperature distribution of the combustor and the fluctuation of the combustor internal pressure of the combustor.

If the temperature distribution of the combustor having a high correlation with NOx is used as a parameter, the fuel-air ratio of each combustor can be suppressed within a predetermined range with high accuracy. Also, if the combustor internal pressure fluctuation of the combustor highly correlated with oscillatory combustion is used as a parameter,
With high accuracy, keep the fuel-air ratio of each combustor within the specified range,
It is possible to quickly suppress the occurrence of oscillatory combustion. As a result, even if there is manufacturing variation in each combustor, it is possible to keep the fuel-air ratio constant and reduce variations in premixed flame temperature and combustor internal pressure variation. As a result, the amount of NOx generated can be reduced to a value at the time of design, and high cycle oscillatory combustion can be rapidly reduced to stably operate the gas turbine. Further, in controlling the fuel-air ratio, the flow rate of the air supplied to the combustor is adjusted, so that the existing air adjusting means can be used for the gas turbine. As a result, even if the existing gas turbine is used, the fuel-air ratio can be easily adjusted and the N caused by the manufacturing variation of the combustor can be adjusted.
Problems such as an increase in Ox can be solved.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail with reference to the drawings. The present invention is not limited to this embodiment. Further, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art.

(Embodiment 1) FIG. 1 is an explanatory view showing a fuel supply system for a gas turbine according to the present invention.
FIG. 2 is an explanatory diagram showing a gas turbine to which the fuel supply system for a gas turbine according to the present invention is applied.
The fuel supply system 100 of the gas turbine, in supplying fuel to a plurality of combustors 20 ₁ or the like, the fuel flow rate adjusting means for adjusting the flow rate of fuel supplied to each combustor 20 ₁ to 20 _20, respectively It is characterized in that it is provided upstream of the combustors 20 _{1 to} 20 ₂₀ . In this example, the flow rate adjusting valves 10 ₁ to 10 ₂₀ are used as the fuel flow rate adjusting means.

This gas turbine fuel supply system 10
At 0, 20 combustors 20 each₁~ 20₂₀
And 20 units of variable flow rate fuel flow rate adjustment means
Regulator valve 10₁-10₂₀To use. The combustor and flow rate
The number of regulators and valves is not limited to this, and gas turbines (illustrated
It can be changed appropriately according to the specifications of (No). Also, Gaster
Trial run the bottles, each combustor 20₁~ 20₂₀Burning in
Variations such as firing temperature and fluctuations in combustor pressure were found.
Flow control valve 10 so that the flow rate is kept within a predetermined range. ₁-10
₂₀After adjusting, remove unnecessary flow rate adjustment valves.
May be used. Therefore, each combustor 20₁~ 20₂₀
Flow rate adjusting valve 10 as fuel flow rate adjusting means₁~
10₂₀At least one combustor
A fuel flow rate adjusting means may be provided.

After the fuel f is adjusted to a predetermined pressure by the pressure adjusting valve 2, the flow rate is adjusted by the flow rate adjusting valve 4 so that the fuel f has a predetermined fuel air ratio. Here, the fuel-air ratio means the ratio f / a of the fuel f and the air a supplied to the combustor (the same applies hereinafter). The fuel f that has passed through the flow rate adjusting valve 4 is branched after passing through the shutoff valve 6 and is supplied to each of the flow rate adjusting valves 10 ₁ to 10 ₂₀ and each of the combustors 20 _{1 to} 20 ₂₀ . The shutoff valve 6 is used for the fuel f when an emergency stop of the gas turbine (not shown) is performed.
Shut off the source of electricity. Here, gas fuel such as natural gas or coal reformed gas is generally used as the fuel f, but liquid fuel such as light oil or heavy light oil is also used as necessary.

As shown in FIG. 2, when the operation of the gas turbine 200 is started, compressed air is supplied from the compressor 210 to the combustors 20 _{1 and the} like. This compressed air is mixed with the fuel f to form a premixed gas and burns to form a premixed flame. Then, high-temperature and high-pressure combustion gas G is generated from the premixed flame, and the turbine 22 of the gas turbine 200 is generated.
Drive 0. Since the generator 230 is connected to the turbine 220, when the turbine 220 is driven, the generator 2
30 generates electric power.

Each of the combustors 20 _{1 to} 20 ₂₀ is provided with a temperature sensor 30 ₁ to 30 ₂₀ (see FIG. 1) to measure the premixed flame temperature of each of the combustors 20 _{1 to} 20 ₂₀ . Then, by adjusting the flow rate adjusting valves 10 ₁ to 10 ₂₀ in accordance with the premixed flame temperatures of the combustors 20 _{1 to} 20 ₂₀ ,
The flow rate of the fuel f supplied to each combustor is adjusted. For example,
When the premixed flame temperature is higher than the preset temperature, less fuel is supplied, and when the premixed flame temperature is lower than the preset temperature, more fuel is supplied. The adjustment of each of the flow rate adjusting valves 10 ₁ to 10 ₂₀ may be performed manually by manual control or by automatic control described later.

Here, in the conventional gas turbine fuel supply system 900 (see FIG. 9), each combustor 920 is used.
It was not possible to adjust the flow rate of the fuel f supplied to _{1 to} 920 ₂₀ . As a result, each combustor 920 _{1 to} 920
_In some cases, there was a difference of about 40 ° C. in the premixed flame temperature due to the manufacturing variation of ₂₀ . Further, in a combustor in which the fuel-air ratio is increased due to the above manufacturing variations, there are cases in which fluctuations in the combustor internal pressure become large and high-cycle oscillatory combustion is likely to occur.

This gas turbine fuel supply system 10
In 0, by the respective combustor 20 ₁ to 20 ₂₀ each of the flow regulating valve 10 ₁ to 10 ₂₀ provided upstream of, can adjust the flow rate of fuel supplied to each combustor 20 ₁ to 20 _20. Therefore, even if there is manufacturing variation in each combustor 20 ₁ to 20 _20, it can reduce the variation of the premixed flame temperature and combustor pressure fluctuations and maintaining the fuel-air ratio constant. This will be described with reference to FIG.

FIG. 3 is an explanatory diagram showing the relationship between the fuel-air ratio f / a of the gas turbine and the combustor internal pressure fluctuation ΔP. Here, the combustor internal pressure fluctuation ΔP is the maximum value Pmax of the combustor internal pressure P.
And the minimum value Pmin, and ΔP = Pmax−Pmi
It can be represented by n. When the fluctuation ΔP of the internal pressure of the combustor is within a predetermined range, the combustion vibration is below a predetermined value, so that the gas turbine can be operated stably. Now, the fuel / air ratio f /
When a is in the range of A, the combustor internal pressure fluctuation ΔP is in the predetermined range ΔP ₁
It becomes the following and shall be able to operate stably.

[0032] FIG. 3 (b), conventional combustor 920 _1-9
Of 20 ₂₀ (see FIG. 9), the fuel-air ratio f / a is the smallest 920 _1, and the fuel-air ratio f / a is the largest 9 20
Shows the 20 _{2 0.} As shown in the same figure, in the conventional combustors 920 _{1 to} 920 ₂₀ , since the fuel-air ratio f / a had a large variation, all the combustors 920 _{1 to} 92 ₁
The range in which 0 ₂₀ can be stably operated was the range of the diagonal lines shown in FIG.

[0033] However, in the fuel supply system 100 (see FIG. 1), the variation of the fuel-air ratio f / a of each combustor 20 ₁ to 20 ₂₀ (see FIG. 1) can be made extremely small. For example, the fuel supply system 100 allows each combustor 20
_When the variation of the fuel-air ratio f / a of _{1 to} 20 ₂₀ (see FIG. 1) is suppressed as shown in FIG. 3 (a), the region of the fuel-air ratio f / a in which stable operation is possible is shown in FIG. Expand to the shaded area in a). As a result, the amount of NOx generated can be reduced to the value at the time of design, and high-cycle oscillating combustion can be reduced to stably operate the gas turbine. In addition, FIG.
Of the combustor 20 ₁ to 20 ₂₀ (see FIG. 1) in the present invention, and 20 ₁ are those fuel-air ratio f / a is the smallest, the 20 ₂₀ and fuel-air ratio f / a is largest of Shows.

Further, since the flow rate adjusting valves 10 ₁ to 10 ₂₀ can significantly reduce the influence caused by the manufacturing variation of the combustors 20 _{1 to} 20 ₂₀ , the manufacturing variation can be corrected as a result. Therefore, each combustor 20 ₁
Because without increasing the 20 ₂₀ manufacturing accuracy of indiscriminately these can be used, it is possible to reduce the manufacturing cost of each combustor 20 ₁ to 20 _20, also yield can be improved. Further, since the combustor can be manufactured even if the manufacturing technology is not so high, it is not necessary to provide sophisticated manufacturing equipment.

In the above description, the temperature of the premixed flame is measured by the temperature sensors 30 ₁ to 30 ₂₀ , and the fuel f supplied to the combustors 20 _{1 to} 20 ₂₀ is measured based on the measured temperature.
Had been adjusted of the flow rate may be measured combustor internal pressure of each combustor 20 ₁ to 20 each combustor includes a pressure sensor ₂₀ 20 ₁ to 20 _20. Here, the fuel f supplied to the combustor
When the flow rate is large, the fuel-air ratio is large, and high-cycle oscillating combustion is likely to occur. When the fuel-air ratio is small, low-cycle oscillating combustion is likely to occur.

Therefore, since a high-cycle oscillatory combustion occurs in a combustor in which the internal pressure of the combustor fluctuates frequently during a certain period of time, the flow rate of the fuel supplied to such a combustor is reduced to reduce the fuel-air ratio. To reduce. This can reduce high cycle oscillatory combustion. Further, in a combustor in which fluctuations in the internal pressure of the combustor are small during a certain period of time, low-cycle oscillating combustion occurs, so the flow rate of fuel supplied to such a combustor is increased to increase the fuel-air ratio. . This can reduce low cycle oscillatory combustion. By doing so, it is possible to reduce oscillating combustion that makes the operation of the gas turbine unstable, so that the gas turbine can be operated stably. As a result, the situation where the gas turbine is stopped due to an increase in oscillatory combustion can be avoided, so that the gas turbine power plant using the fuel supply system 100 of the gas turbine can stably supply electric power.

(Modification) FIG. 4 is an explanatory view showing a part of a gas turbine fuel supply system according to a modification of the first embodiment. This gas turbine fuel supply system 10
Reference numeral 1 is provided with a detection means and a control means for detecting the temperature of the premixed flame or the temperature of the combustor wall affected by the premixed flame (hereinafter, both are collectively referred to as the temperature of the premixed flame). The feature is that the fuel flow rate adjusting means is automatically controlled. Since other configurations are similar to those of the first embodiment, the description thereof will be omitted and the same components will be denoted by the same reference numerals.

As shown in FIG. 4, the temperature sensor 30 ₁ provided in the combustor 20 ₁ measures the temperature T ₁ of the premixed flame generated by the combustor 20 _1. The measured temperature T ₁ of the premixed flame is converted into an electrical signal and then A /
The control device 5 converts the digital signal by the D converter 40.
It is taken into the processing unit 51 of 0. Further, a preset temperature T of the premixed flame is stored in the storage unit 52 of the control device 50, and the processing unit 51 reads this temperature T from the storage unit 52 and compares T with T ₁ .

As a result of comparing T and T ₁ , when T ₁ is lower than the preset temperature T of the premixed flame,
The processing unit 51 sends a control signal to the control unit 53 so as to open the flow rate adjusting valve 11 ₁ and supply more fuel f to the combustor 20 ₁ . In response to this control signal, the control unit 53 operates the flow rate adjusting valve control actuator 55 to open the flow rate adjusting valve 11 ₁ and supply more fuel f to the combustor 20 ₁ to supply the temperature of the premixed flame. To raise. When T ₁ is higher than the preset temperature T of the premixed flame,
On the contrary, the flow rate adjusting valve 11 ₁ is closed to reduce the amount of the fuel f supplied to the combustor 20 ₁ .

If the flow rate adjusting valve 11 ₁ is adjusted by automatic control as in this modification, the temperature of the predetermined premixed flame can be adjusted quickly and reliably. As a result, it is possible to reduce the increase in NOx due to the temperature variation of the premixed flame. Here, as described in the first embodiment, instead of the temperature T ₁ of the premixed flame, a combustor 20 flow regulating valve 11 _{1 1} of the combustor pressure P ₁ as the fuel flow rate control parameter
May be controlled. Fluctuations in the combustor internal pressure P ₁ are directly related to oscillatory combustion. Therefore, in order to perform control to suppress oscillatory combustion in the combustor 20 ₁ or the like, it is preferable to use the combustor internal pressure P ₁ as the fuel flow rate control parameter rather than the premixed flame temperature T ₁ as the fuel flow rate control parameter. However, quicker and more reliable control is possible. In the above description, only the combustor 20 ₁ has been described, but the same applies to the other combustors 20 _{2 and the} like. Here, the control device 50 may be prepared for each combustor 20 ₁ to 20 ₂₀ each, by the use by dividing the single control device 50 times, each flow regulating 11 ₁ to 11 ₂₀ valve You may control.

The storage unit 52 is a non-volatile memory such as a hard disk device, a magneto-optical disk device, a flash memory, a read-only storage medium such as a CD-ROM, or a RAM (Random Access Memory). Such a volatile memory or a combination thereof can be used. Further, the processing unit 51 may be realized by dedicated hardware. Further, the processing unit 51 is composed of a memory and a CPU (central processing unit), and realizes the function by loading a program (not shown) for realizing the function of the processing unit 51 into the memory and executing the program. May be

The control device 50 may realize its function by loading an input device, a display device or the like (neither of which is shown) as a peripheral device into a memory and executing the device. Further, it is assumed that an input device, a display device, etc. (neither shown) are connected as peripheral devices to the control device 50. Here, the input device refers to an input device such as a keyboard and a mouse. The display device refers to a CRT (Cathode Ray Tube), a liquid crystal display device, or the like.

(Second Embodiment) FIG. 5 is an explanatory diagram showing a fuel supply system for a gas turbine according to a second embodiment. The fuel supply system 102 for the gas turbine has substantially the same configuration as the fuel supply system 100 for the gas turbine according to the first embodiment, but uses an orifice that is a fixed flow rate adjusting means instead of the flow rate adjusting valve. The points are different. Since other configurations are similar to those of the first embodiment, the description thereof will be omitted and the same components will be denoted by the same reference numerals.

When operating the gas turbine, the compressor
(Not shown) to each combustor 20₁~ 20₂₀Compressed air
It is supplied and mixed with fuel f. Premixed gas mixture of both
It becomes a combined gas, which burns to form a premixed flame.
Each combustor 20₁~ 20₂₀Upstream of the orifice 12₁~
12₂₀Is provided. And with different opening areas
Liffith Plate 12p₁By replacing it with
Each combustor 20₁~ 20 ₂₀The flow rate of fuel f supplied to
It can be adjusted.

This gas turbine fuel supply system 10
In No. 2, first, the gas turbine is operated, and each combustor 2
The temperature of each premixed flame produced in 0 _{1 to} 20 ₂₀ is measured to grasp the variation in each combustor 20 _{1 to} 20 ₂₀ . Once you understand the variations of each combustor 20 ₁ to 20 _20, supplied to the combustor 20 ₁ to 20 each combustor 20 ₁ to 20 ₂₀ as the temperature of the premixed flame is in the range of provisions to be generated at ₂₀ The flow rate of the fuel f is calculated. Then, an orifice plate 12p ₁ having an opening area corresponding to the flow rate is incorporated into each of the orifices 12 _{1 to} 12 ₂₀ . In this way, the temperature of the premixed flame generated in each combustor 20 _{1 to} 20 ₂₀ is kept within the specified range.

This gas turbine fuel supply system 10
In 2, the respective orifices 12 ₁ to 12 ₂₀ provided upstream of each combustor 20 ₁ to 20 _20, can adjust the flow rate of the fuel supplied to the combustor 20 ₁ to 20 _20. Therefore, even if there is manufacturing variation in each combustor 20 ₁ to 20 _20, can reduce variations in temperature and combustor pressure fluctuations of the premixed flame while maintaining the fuel-air ratio constant.

Further, instead of using an expensive flow rate adjusting valve as in the fuel supply system 100 (see FIG. 1) of the gas turbine according to the first embodiment, an inexpensive orifice is used. This can reduce the manufacturing cost of the gas turbine. Further, since the orifice has a constant opening area, once the flow rate is determined, the flow rate does not change thereafter. As a result, the fuel f
Since the flow rate does not change, stable operation can be performed for a long period of time. In addition, maintenance and inspection work can be reduced.

The fixed flow rate adjusting means may be provided with a differential pressure compensating function. When such a fixed flow rate adjusting means is used, a constant flow rate can be maintained even if the pressure of the fuel f in the upstream and downstream of the fixed flow rate adjusting means fluctuates due to load fluctuation or the like.
The gas turbine can be operated more stably. In place of the orifice 12 ₁ to 12 _20, by using the throttle valve and the venturi as a flow fixed adjusting means, thereby may adjust the flow rate of supplied fuel f to each combustor 20 ₁ to 20 ₂₀ . The same applies to these points.

(Third Embodiment) FIG. 6 is an explanatory view showing a fuel supply system for a gas turbine according to a third embodiment. The fuel supply system 103 for the gas turbine has substantially the same configuration as the fuel supply system 102 for the gas turbine according to the second embodiment, but the fixed flow rate adjusting means and the bypass means are provided upstream of the combustor. And a bypass fuel passage for supplying fuel to the combustor. The fixed fuel adjusting means is adjusted to a predetermined flow rate while the fuel is supplied to the combustor by bypassing the fixed flow rate adjusting means. Since other configurations are similar to those of the first embodiment, the description thereof will be omitted and the same components will be denoted by the same reference numerals.

Orifices 12 _{1 to} 12 ₂₀ are provided upstream of the combustors 20 _{1 to} 20 ₂₀ as fixed flow rate adjusting means. Then, each combustor 2 is replaced by replacing it with an orifice plate 12p _{1 having} a different opening area.
The flow rate of the fuel f supplied to 0 _{1 to} 20 ₂₀ can be adjusted. The upstream side opening / closing valve 13 serving as fuel switching means is provided upstream and downstream of the orifices 12 _{1 to} 12 ₂₀ , respectively.
a _{1 to} 13a ₂₀ and downstream side opening / closing valves 13c _{1 to} 13c ₂₀ are provided. These orifices 12 ₁ to 12
Through ₂₀ in each combustor 20 ₁ to 20 ₂₀ is opened when supplying fuel f. Then, the orifices 12 _{1 to} 12 ₂₀ are closed when the flow rate is adjusted.

The upstream opening / closing valves 13a _{1 to} 13a ₂₀ and the downstream opening / closing valves 13c _{1 to} 13c ₂₀ do not need to have a function of adjusting the flow rate of the fuel f, but have a function of blocking and passing the fuel f. Good. Therefore, it is not necessary to use an expensive flow rate adjusting valve as used in the first embodiment. This is based on the bypass fuel passage opening / closing valve 1 described below.
3b ₁ 13 b ₂₀ is the same.

Further, upstream of each of the combustors 20 _{1 to} 20 ₂₀ , the orifices 12 _{1 to} 12 ₂₀ are bypassed and the combustor 2 is
Bypass fuel passage 60 ₁ for supplying fuel f to 0 _{1 to} 20 ₂₀
-60 ₂₀ are provided. This bypass fuel passage 60
The _through 603 _20, bypass the fuel passage on-off valve 13b ₁ 13 b ₂₀ is provided with a fuel switching means. Then, when the flow rate adjusting orifice 12 ₁ to 12 ₂₀ open these supply fuel f through the bypass fuel passage 60 _through 603 ₂₀ to each combustor 20 ₁ to 20 _20.

This gas turbine fuel supply system 10
In Fig. 3, first, the bypass fuel passage opening / closing valve 13b
_{1 to} 13b ₂₀ are closed, and fuel f is supplied to each combustor 20 _{1 to} 20 ₂₀ through the orifices 12 _{1 to} 12 ₂₀ to operate the gas turbine. Each combustor 20 21 _to this time
The temperature of each premixed flame generated at 0 ₂₀ is measured to grasp the variation of each combustor 20 _{1 to} 20 ₂₀ . Each combustor 2
If the variation of 0 _{1 to} 20 ₂₀ is grasped, each combustor 20 ₁ to
The flow rate of the fuel f supplied to each of the combustors 20 _{1 to} 20 ₂₀ is determined so that the temperature of the premixed flame generated in 20 ₂₀ falls within the specified range. Then, an orifice plate 12p ₁ or the like having an opening area corresponding to this flow rate is prepared.

Next, the bypass fuel passage opening / closing valve 13b ₁
˜13b ₂₀ are opened, and the fuel f is supplied to each of the combustors 20 _{1 to} 20 ₂₀ via the bypass fuel passages 60 _{1 to} 60 ₂₀ to operate the gas turbine. This is to replace the orifice plate 12p _{1 and the} like without stopping the operation of the gas turbine. At this time, the orifices 12 _{1 to} 12 ₂₀
Upstream on-off valves 13a ₁ to ₁ provided upstream and downstream of the
3a ₂₀ and the downstream opening / closing valves 13c _{1 to} 13c ₂₀ are closed. Here, also closing the downstream side switching valve 13c ₁ ~13c _20, the fuel f from the bypass fuel passage 60 _through 603 ₂₀ side to an orifice 12 ₁ to 12 ₂₀ is to prevent backflow. Incidentally, the downstream side switching valve 13c ₁ ~13c ₂₀
Instead of, the check valve that blocks the flow of the fuel f from the bypass fuel passages 60 _{1 to} 60 ₂₀ side toward the orifices 12 _{1 to} 12 ₂₀ side may be used. According to the check valve, the fuel f can be flown to the orifice 12 _{1 and the} like without requiring opening / closing operation, which is preferable because the operation is easy.

[0055] The fuel f through the bypass fuel passage 60 _through 603 ₂₀ while being supplied to each combustor 20 ₁ to 20 _20,
Use the prepared orifice plate 12p ₁ etc.
It is incorporated in 2 ₁ etc. After incorporation is complete, we close the on-off valve 13b ₁ 13 b _{2 0} bypass fuel passage,
Upstream side switching valve 13a ₁ ~13a ₂₀ and the downstream side switching valve 13c ₁
Open up to 13c ₂₀ . And the orifices 12 _{1 to} 12
Supplying fuel f through ₂₀ in each combustor 20 ₁ to 20 _20. In this way, the temperature of the premixed flame generated in each combustor 20 _{1 to} 20 ₂₀ is kept within the specified range.

This gas turbine fuel supply system 10
In 3, the orifice 1 which is a fixed flow rate adjusting means
2 _{1 to} 12 ₂₀ and bypass fuel passages 60 _{1 to} 60 ₂₀ bypassing this and supplying fuel to the combustor. Therefore, even when the gas turbine is in operation, the flow rate of the fuel f can be adjusted by replacing the orifice plates 12p ₁ of the orifices 12 _{1 to} 12 _{20 and} the like. Therefore, since it is many times the flow rate adjusted while operating a gas turbine, it is possible to adjust the fuel-air ratio in each combustor 20 ₁ to 20 ₂₀ more accurately. As a result, the generation of NOx can be further suppressed and the generation of oscillatory combustion can be further suppressed, so that the gas turbine can be operated more stably. Further, since the operation rate of the gas turbine can be increased, the gas turbine can be used for power supply for a longer time. Also, since the fuel-air ratio can be adjusted when power is supplied,
Since it is not necessary to adjust the fuel-air ratio outside the power supply time, labor costs can be saved accordingly.

Further, as shown in FIG. 6 (b), the upstream side opening is performed.
Valve 13a₁And bypass fuel passage opening / closing valve 13b₁With
Instead, the three-way valve 14 is used as fuel switching means.₁using
Good. Orifice 12₁When adjusting the three-way valve 14₁
Adjust the bypass fuel passage 60₁Via combustor 2
0₁Is supplied with fuel f. Orifice 12₁And so on
When finished, three-way valve 14₁Adjust the downstream opening / closing valve 13c₁To
Open and orifice 12 ₁Through the combustor 20₁Fuel to etc
supply f. By doing so, as shown in FIG.
Switching compared to the gas turbine fuel supply system 103
Since the number of flaps can be reduced, manufacturing costs can be reduced.
You can Also, because the number of switching valves is reduced,
The number of moving parts in the fuel supply system can be reduced,
It can be highly reliable.

(Fourth Embodiment) FIG. 7 is an explanatory view showing a fuel supply system for a gas turbine according to a fourth embodiment. The fuel-air ratio adjusting system 105 of this gas turbine is
The bypass passage 70 that supplies the combustion air a supplied from the compressor to the combustor transition piece 21b by bypassing the combustor 21 is provided. The bypass air flow rate adjusting valve 15 provided in the bypass flow passage 70 serves as a bypass air flow rate adjusting valve to adjust the fuel-air ratio of the combustor 21.

Next, a method of adjusting the fuel air ratio in the fuel air ratio adjusting system 105 of the gas turbine will be described.
When the gas turbine has a partial load, the flow rate of the fuel f supplied to the combustor 21 is reduced, but in order to keep the fuel-air ratio constant, the flow rate of the combustion air a supplied from the compressor is also reduced. , It is necessary to reduce according to this decrease. However, if the flow rate of air sent from the compressor is excessively reduced, the compressor may cause surging. As a result, the operation of the turbine may become unstable, and this air flow rate cannot be changed so much. Then, as a result of increasing the amount of the combustion air a supplied to the combustor 21, the fuel-air ratio becomes small and the combustion becomes unstable.
Therefore, a part of the air a supplied to the combustor 21 is caused to flow to the combustor transition piece 20b via the bypass flow passage 70. The air flow rate for bypassing the combustor 21 is adjusted by the bypass air flow rate adjusting valve 15 provided in the bypass flow passage 70.

Fuel-air ratio adjusting system 1 of this gas turbine
In No. 05, variations in the fuel-air ratio due to variations in assembly of the combustor 21 are detected by the bypass air flow rate adjusting valve 15
It is adjusted by. That is, in the combustor 21 having a larger fuel-air ratio than the specified fuel-air ratio, the bypass air flow rate adjusting valve 15 is closed to supply more air to the combustor 21 to reduce the fuel-air ratio. On the other hand, in the combustor 21 having a smaller fuel-air ratio than the specified fuel-air ratio, by opening the bypass air flow rate adjusting valve 15, more air is supplied to the combustor transition piece 21b and supplied to the combustor 21. The fuel-air ratio is reduced by reducing the amount of air used. Thereby, the fuel-air ratios of the plurality of combustors 21 are controlled within a predetermined range.

FIG. 8 is an explanatory view showing another example of the fuel supply system for the gas turbine according to the fourth embodiment. The combustor 22 used in the fuel-air ratio adjusting system 106 of the gas turbine is similar to the combustor 21 in that the bypass passage 70 is used.
The flow rate of the air a supplied from the compressor is adjusted by the air flow rate adjusting valve 16 which is an air flow rate adjusting means without having the above. Therefore, in the fuel-air ratio adjusting system 106 of the gas turbine, the air-flow ratio adjusting valve 16 can adjust the fuel-air ratio variation due to the assembly variation of the combustor 22. That is, in the combustor 22 having a larger fuel-air ratio than the specified fuel-air ratio, the actuator 56 closes the air flow rate adjusting valve 16 to supply more air to the combustor 22 to reduce the fuel-air ratio. To do. On the other hand, in the combustor 22 having a smaller fuel-air ratio than the specified fuel-air ratio, the air flow rate adjusting valve 16 is opened to reduce the amount of air supplied to the combustor 22, thereby reducing the fuel-air ratio. Thereby, the fuel-air ratios of the plurality of combustors 22 are controlled within a predetermined range.

In the fuel-air ratio adjusting systems 105 and 106 of these gas turbines, the fuel-air ratio can be adjusted by utilizing the bypass air flow rate adjusting valve 15 and the air flow rate adjusting valve 16 which are already installed. Therefore, it is economical because it is possible to reduce variations in the temperature of the premixed flame and variations in the internal pressure of the combustor due to variations in manufacturing of the combustors without requiring new equipment investment. As the parameter for controlling the bypass air flow rate adjusting valve 15 or the air flow rate adjusting valve 16, the temperature T of the premixed flame or the combustor internal pressure P of the combustor 20 is used as described in the first embodiment and the like. Can be used.

[0063]

As described above, in the fuel supply system for a gas turbine according to the present invention (claim 1), the flow rate of the fuel supplied to the combustor is adjusted by the fuel flow rate adjusting means. Therefore, variations in combustion temperature due to variations in manufacturing combustors can be suppressed within a predetermined range. As a result, even if there is manufacturing variation in each combustor, it is possible to keep the fuel-air ratio constant and reduce variations in the temperature of the premixed flame and variations in the combustor internal pressure. As a result, NO
It is possible to reduce the amount of x generated to the value at the time of design, reduce high cycle oscillatory combustion, and stably operate the gas turbine.

Further, in the fuel supply system for a gas turbine according to the present invention (claim 2), in a gas turbine having a plurality of combustors, the flow rate of the fuel supplied to the combustors is adjusted upstream of each combustor. A possible fuel flow rate adjusting means is provided. Therefore, the flow rate of the fuel supplied to each combustor can be adjusted separately, and the degree of freedom in adjustment is improved.

In the fuel supply system for the gas turbine according to the present invention (claim 3), the flow rate of the fuel supplied to the combustor is adjusted by the variable flow rate fuel flow rate adjusting means. As a result, the fuel-air ratio of each combustor can be adjusted even during operation of the gas turbine, so there is no need to stop the gas turbine in order to adjust the fuel flow rate.
Therefore, the fuel-air ratio of each combustor can be easily adjusted, and the operating rate of the gas turbine can be increased.

Further, in the fuel supply system for a gas turbine according to the present invention (claim 4), the fuel supplied to the combustor is changed by changing the fixed flow rate adjusting means such as the orifice or the throttle valve to a different flow rate. The flow rate of was adjusted. Therefore, once the flow rate of the fuel is determined, it is fixed to this flow rate, so that stable operation can be performed while minimizing the fluctuation of the fuel flow rate with the passage of time. Also, since it uses an inexpensive orifice etc. compared to the flow rate adjustment valve,
Manufacturing cost can be suppressed.

Further, in the fuel supply system for a gas turbine according to the present invention (claim 5), the flow rate of the fuel supplied to the combustor is adjusted by the fixed flow rate adjusting means such as the orifice and the throttle valve, and the adjustment is being performed. This fixed flow rate adjusting means is bypassed to supply fuel to the combustor. Therefore, the flow rate of the fuel supplied to the combustor can be adjusted even during operation of the gas turbine. As a result, the fuel-air ratio of each combustor can be easily adjusted, and the gas turbine operating rate can be increased. Further, since the fixed flow rate adjusting means is used, it is possible to minimize the flow rate fluctuation of the fuel with the passage of time and perform stable operation.

Further, in the gas turbine according to the present invention (claim 6), since the fuel supply system is provided, it is possible to suppress the variation of the combustion temperature due to the production variation of the combustor within a predetermined range. it can. As a result, even if there is manufacturing variation in each combustor, it is possible to keep the fuel-air ratio constant and reduce variations in the temperature of the premixed flame and variations in the combustor internal pressure. As a result, it is possible to reduce the amount of NOx generated to the value at the time of design, reduce high cycle oscillatory combustion, and operate the gas turbine stably. In addition, since a combustor having manufacturing variations can be used, the manufacturing cost of the gas turbine can be reduced.

Further, in the fuel-air ratio adjusting method of the gas turbine according to the present invention (claim 7), the fuel supplied to each combustor is adjusted to adjust the fuel-air ratio of the gas turbine.
At least one of the combustor temperature distribution and the combustor internal pressure fluctuation is used as the parameter.
As described above, if the temperature distribution of the combustor having a high correlation with NOx is used as a parameter, the fuel-air ratio of each combustor can be suppressed within a predetermined range with high accuracy. Also, if the combustor internal pressure fluctuation of the combustor highly correlated with oscillatory combustion is used as a parameter,
With high accuracy, keep the fuel-air ratio of each combustor within the specified range,
It is possible to quickly suppress the occurrence of oscillatory combustion. As a result, even if there are manufacturing variations in each combustor, the amount of NOx generated can be reduced to the design value by maintaining the fuel-air ratio of each combustor constant, and high-cycle oscillatory combustion can be rapidly reduced. The gas turbine can be operated stably.

Further, in the fuel-air ratio adjusting method of the gas turbine according to the present invention (claim 8), the fuel-air ratio of each combustor is adjusted within a predetermined range by adjusting the flow rate of the air supplied to each combustor. Since it is controlled to be within the range, it is possible to suppress the variation in the combustion temperature due to the variation in manufacturing the combustor within a predetermined range. As a result, even if there is manufacturing variation in each combustor, the fuel-air ratio is kept constant to reduce the amount of NOx generated to the design value, and high cycle oscillatory combustion is reduced to stabilize the gas turbine. And you can drive.

Further, in the fuel-air ratio adjusting method of the gas turbine according to the present invention (claim 9), a part of the supplied air is mixed with the combustion gas without being combusted depending on the load of the gas turbine. In adjusting the fuel-air ratio of a gas turbine having a plurality of combustors, the fuel-air ratio of the combustor is adjusted by adjusting the amount of air mixed with the combustion gas.
Further, in the fuel-air ratio adjusting method for a gas turbine according to the present invention (claim 10), the fuel-air ratio for a gas turbine including a plurality of combustors having air flow rate adjusting means capable of adjusting the flow rate of the supplied air is adjusted. In doing so, the fuel-air ratio of the combustor is adjusted by adjusting the air flow rate adjusting means. In the fuel-air ratio adjusting method for these gas turbines, since the fuel-air ratio can be adjusted by using the existing air flow rate adjusting means and the combustor bypass means, a new device is provided for adjusting the fuel-air ratio. No need. As a result, even with an existing gas turbine, the fuel-air ratio can be easily adjusted to solve problems such as an increase in NOx due to variations in the manufacture of combustors.

Further, in the fuel-air ratio adjusting method of the gas turbine according to the present invention (claim 11), the gas is supplied to the combustor according to at least one of the temperature distribution of the combustor and the fluctuation of the combustor internal pressure. The fuel-air ratio of the combustor was adjusted by adjusting the flow rate of air. In this way, NOx
If the temperature distribution of the combustor that is highly correlated with
The fuel-air ratio of each combustor can be suppressed within a predetermined range with high accuracy. Further, if the combustor internal pressure fluctuation of the combustor highly correlated with the oscillatory combustion is used as a parameter, the fuel-air ratio of each combustor can be suppressed within a predetermined range with high accuracy, and the occurrence of oscillatory combustion can be suppressed quickly. it can. As a result, even if there is manufacturing variation in each combustor, these fuel-air ratios can be kept constant, so the amount of NOx generated can be reduced to the value at the time of design, and high-cycle oscillatory combustion can be performed quickly. The gas turbine can be reduced to operate stably. Further, in the control of the fuel-air ratio, the existing air adjusting means can be used in the gas turbine. Therefore, even in the existing gas turbine, the fuel-air ratio can be easily adjusted to reduce NOx caused by the manufacturing variation of the combustor. Can solve problems such as increase.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a fuel supply system for a gas turbine according to the present invention.

FIG. 2 is an explanatory diagram showing a gas turbine to which a fuel supply system for a gas turbine according to the present invention is applied.

FIG. 3 is an explanatory diagram showing a relationship between a fuel-air ratio f / a of a gas turbine and a combustor internal pressure fluctuation ΔP.

FIG. 4 is an explanatory diagram showing a part of a fuel supply system for a gas turbine according to a modification of the first embodiment.

FIG. 5 is an explanatory diagram showing a fuel supply system for a gas turbine according to a second embodiment.

FIG. 6 is an explanatory diagram showing a fuel supply system for a gas turbine according to a third embodiment.

FIG. 7 is an explanatory diagram showing a fuel supply system for a gas turbine according to a fourth embodiment.

FIG. 8 is an explanatory diagram showing another example of the fuel supply system for the gas turbine according to the fourth embodiment.

FIG. 9 is an explanatory view showing a fuel supply system in a conventional gas turbine.

[Explanation of symbols] 10 ₁ , 11 ₁ flow rate adjusting valve 12 ₁ orifice 12p ₁ orifice plate 13b ₁ bypass fuel passage opening / closing valve 13a ₁ upstream side opening / closing valve 13c ₁ downstream side opening / closing valve 15 bypass air flow rate adjusting valve 16 air flow rate adjusting Valves 20 ₁ , 20 ₂ , 21, 21, 22 Combustor 20b Combustor transition piece 70 Bypass passage 100, 101, 102, 103 Fuel supply system 105, 106 Fuel-air ratio adjusting system 200 Gas turbine 210 Compressor 220 Turbine 30 ₁ Temperature sensor 60 ₁ Bypass fuel passage

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F02C 9/32 F02C 9/32 (72) Inventor Katsunori Tanaka 2-1-1 Niihama, Arai-cho, Takasago, Hyogo Prefecture Mitsubishi Heavy Industries, Ltd. Takasago Plant (72) Inventor, Mako Akamatsu 2-1-1, Niihama, Arai Town, Takasago City, Hyogo Prefecture Mitsubishi Heavy Industries Ltd., Takasago Plant

Claims (11)

[Claims] 1. A gas turbine having a plurality of combustors, comprising a fuel flow rate adjusting means capable of adjusting a flow rate of fuel supplied to the combustor upstream of at least one combustor. Fuel supply system. 2. A gas turbine having a plurality of combustors, characterized in that a fuel flow rate adjusting means capable of adjusting a flow rate of fuel supplied to the combustors is provided upstream of each combustor. Fuel supply system. 3. The fuel flow rate adjusting means is a variable flow rate type fuel flow rate adjusting means such as a flow rate adjusting valve capable of varying the fuel flow rate during the supply of the fuel. Gas turbine fuel supply system. 4. The fuel flow rate adjusting means is an orifice,
The fuel supply system for a gas turbine according to claim 1 or 2, wherein the throttle valve, the venturi, and other fixed flow rate adjusting means are fixed flow rate fuel flow rate adjusting means for changing to different flow rates. 5. The fuel flow rate adjusting means is an orifice,
A throttle valve, a venturi or other fixed flow rate adjusting means, a bypass means for bypassing the fixed flow rate adjusting means to supply fuel to the combustor, and either the fixed flow rate adjusting means or the bypass means. And a fuel switching means for flowing the fuel to be supplied to the combustor, wherein the fuel is supplied to the combustor by flowing the fuel to the bypass means while the fixed flow rate adjusting means is being changed. The fuel supply system for a gas turbine according to claim 1 or 2. 6. A compressor for compressing air, a combustor for reacting the air compressed by the compressor with a fuel to generate combustion gas, and supplying fuel to the combustor. One of
5. A gas turbine, comprising: the fuel supply system according to item 1; and a turbine driven by the combustion gas generated by the combustor. 7. When adjusting the fuel-air ratio of a gas turbine having a plurality of combustors, the amount of fuel to be supplied is adjusted according to at least one of the temperature distribution of the combustor and the fluctuation of the combustor internal pressure. A method for adjusting a fuel-air ratio of a gas turbine, comprising: 8. A method for adjusting a fuel-air ratio of a gas turbine, which comprises adjusting a flow rate of air supplied to the combustor when adjusting a fuel-air ratio of a gas turbine including a plurality of combustors. 9. Combustion when adjusting the fuel-air ratio of a gas turbine provided with a plurality of combustors for mixing a part of the supplied air with the combustion gas without supplying it to the combustion according to the load of the gas turbine. A fuel-air ratio adjusting method for a gas turbine, characterized in that a fuel-air ratio of a combustor is adjusted by adjusting an amount of air mixed with gas. 10. When adjusting the fuel-air ratio of a gas turbine equipped with a plurality of combustors having air flow rate adjusting means capable of adjusting the flow rate of supplied air, the fuel of the combustor is adjusted by adjusting the air flow rate adjusting means. A method for adjusting a fuel-air ratio of a gas turbine, which comprises adjusting an air ratio. 11. When adjusting a fuel-air ratio of a gas turbine having a plurality of combustors, air supplied to the combustor according to at least one of a temperature distribution of the combustor and a fluctuation of a combustor internal pressure of the combustor. The fuel-air ratio adjusting method for a gas turbine according to any one of claims 7 to 10, characterized in that the flow rate is adjusted.