Gas turbine burner and gas turbine

Abstract

A gas turbine combustor according to at least one embodiment includes: a low-combustibility fuel flow regulating unit for independently regulating the supply of low-combustibility fuel to a first fuel injector and a second fuel injector; a high-combustibility fuel flow regulating unit for independently regulating the supply of high-combustibility fuel to the first fuel injector and the second fuel injector, the high-combustibility fuel having a higher combustion rate than the low-combustibility fuel; and a controller configured to control the low-combustibility fuel flow regulating unit and the high-combustibility fuel flow regulating unit according to the operating state of the gas turbine, so that the ratio of a first ratio of high-combustibility fuel to the total first fuel injected by the first fuel injector and a second ratio of high-combustibility fuel to the total second fuel injected by the second fuel injector changes.

Description

Technical Field

[0001] This disclosure relates to a gas turbine combustor and a gas turbine. This application claims priority based on Japan Patent Application No. 2021-002117 filed with the Japan Patent Office on January 8, 2021, the contents of which are incorporated herein by reference. Background Technology

[0002] For example, in gas turbines used for power generation, the operating mode is sometimes switched to turndown operation to cope with the fluctuations in electricity demand during the day and night. In turndown operation, the flow rate of combustion gas through the turbine is reduced, causing the gas turbine to operate at a lower output than during rated operation (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-137390 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] If the output of a gas turbine is reduced by operating it under reduced load, the combustion temperature in the burner decreases, resulting in an increase in the production of unburned substances such as carbon monoxide and hydrocarbons, as well as combustion vibration. However, in order to flexibly respond to the aforementioned changes in electricity demand, efforts are being made to reduce the lower limit of the output during reduced load operation and thus expand the application range of gas turbines.

[0008] In order to reduce the lower limit of output during reduced load operation, it is preferable to mix and burn highly combustible fuels such as hydrogen, which have a relatively high combustion rate.

[0009] However, increasing the mixing and combustion rate of highly combustible fuels increases the risk of backfire. In other words, reducing the lower limit of output during reduced-load operation and minimizing the risk of backfire represent a trade-off.

[0010] In view of the above, the purpose of at least one embodiment of this disclosure is to achieve both reducing the lower limit of output during unloaded operation and reducing the risk of tempering.

[0011] Solution for solving the problem

[0012] (1) The gas turbine burner of at least one embodiment of the present disclosure includes:

[0013] First fuel injector;

[0014] Second fuel injector;

[0015] A combustion section that ignites the fuel injected from the first fuel injector and the second fuel injector;

[0016] A low-combustible fuel flow regulating unit is used to independently regulate the supply of low-combustible fuel to the first fuel injector and the second fuel injector.

[0017] A high-combustibility fuel flow regulating unit, used to independently regulate the supply of high-combustibility fuel to the first fuel injector and the second fuel injector, wherein the high-combustibility fuel has a higher combustion rate than the low-combustibility fuel; and

[0018] The controller is configured to control the low-combustibility fuel flow regulating unit and the high-combustibility fuel flow regulating unit according to the operating state of the gas turbine, so as to change the ratio of a first ratio of the high-combustibility fuel to the total first fuel injected by the first fuel injector and a second ratio of the high-combustibility fuel to the total second fuel injected by the second fuel injector.

[0019] (2) The gas turbine of at least one embodiment of the present disclosure has a gas turbine burner with the structure described in (1) above.

[0020] Invention Effects

[0021] According to at least one embodiment of this disclosure, both reducing the lower limit of output during unloaded operation and reducing the risk of tempering are achieved. Attached Figure Description

[0022] Figure 1 This is a schematic structural diagram showing several embodiments of a gas turbine.

[0023] Figure 2 This is a cross-sectional view showing several embodiments of a burner.

[0024] Figure 3 This is a cross-sectional view showing the main parts of a burner according to several embodiments.

[0025] Figure 4A This diagram schematically illustrates the configuration of each fuel injector when viewing a burner of several embodiments from the downstream side to the upstream side along the axial direction of the burner.

[0026] Figure 4B This diagram schematically illustrates the configuration of each fuel injector when viewing a burner of another embodiment from the downstream side to the upstream side along the axial direction of the burner.

[0027] Figure 5 This is a diagram showing an outline of the fuel supply system for a burner according to several embodiments.

[0028] Figure 6A This is a chart illustrating an example of the relationship between the first and second ratios and indicators representing the operating status of a gas turbine.

[0029] Figure 6B This is another example of a chart showing the relationship between the first and second ratios and indicators representing the operating status of a gas turbine.

[0030] Figure 6C These are charts illustrating other examples of the relationship between the first ratio and indicators representing the operating status of the gas turbine.

[0031] Figure 6D These are charts illustrating other examples of the relationship between the first ratio and indicators representing the operating status of the gas turbine.

[0032] Figure 6E This is another example of a graph showing the relationship between the second ratio and an indicator representing the operating status of a gas turbine.

[0033] Figure 7 This is an overall schematic diagram of several implementations of the combustion control device.

[0034] Figure 8 This is a block diagram illustrating the structure of the calculation logic of CLCSO in a combustion control device according to several embodiments. Detailed Implementation

[0035] Hereinafter, several embodiments of the present invention will be described with reference to the accompanying drawings. The dimensions, materials, shapes, and relative arrangements of the constituent components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples.

[0036] For example, expressions such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" indicate relative or absolute configurations, not only in a strict sense, but also in a state of relative displacement by angle or distance with tolerance or to the extent that the same function can be obtained.

[0037] For example, expressions such as "same," "equal," and "homogeneous" that indicate the state of equality of things not only indicate a state of strict equality, but also indicate a state of difference in the degree to which the same function can be obtained due to tolerances.

[0038] For example, the descriptions of shapes such as quadrilaterals and cylindrical shapes not only refer to quadrilaterals and cylindrical shapes in a strict geometric sense, but also to shapes that include concave and convex parts, chamfered parts, etc., within the range where the same effect can be obtained.

[0039] On the other hand, expressions such as "possessing," "containing," "equipped with," "including," or "having" a constituent element are not exclusive expressions that exclude the existence of other constituent elements.

[0040] (Regarding gas turbines 1)

[0041] Figure 1 This is a schematic structural diagram showing several embodiments of a gas turbine 1.

[0042] Reference Figure 1 An example of a gas turbine that is used as an application object of a gas turbine burner in several implementation methods will be described.

[0043] like Figure 1 As shown, the gas turbine 1 in several embodiments includes: a compressor 2 for generating compressed air as an oxidant; a gas turbine combustor 4 for generating combustion gases using compressed air and fuel; and a turbine 6 configured to rotate driven by the combustion gases. In the case of the gas turbine 1 for power generation, a generator (not shown) is connected to the turbine 6, and power is generated using the rotational energy of the turbine 6. In the following description, the gas turbine combustor 4 will also be simply referred to as combustor 4.

[0044] Specific structural examples of each part in the gas turbine 1 of several embodiments will be described.

[0045] The compressor 2 in several embodiments includes: a compressor chamber 10; an air intake 12 disposed on the inlet side of the compressor chamber 10 for intake of air; a rotor 8 configured to pass through both the compressor chamber 10 and the turbine chamber 22 described later; and various blades disposed within the compressor chamber 10. The various blades include: inlet guide vanes 14 disposed on the air intake 12 side; a plurality of stationary vanes 16 fixed to the compressor chamber 10 side; and a plurality of moving vanes 18 arranged alternately relative to the stationary vanes 16 on the rotor 8. It should be noted that the compressor 2 may also include other components such as an extraction chamber (not shown). In such a compressor 2, air intake from the air intake 12 is compressed by the plurality of stationary vanes 16 and the plurality of moving vanes 18 to become high-temperature, high-pressure compressed air. Furthermore, the high-temperature, high-pressure compressed air is delivered from the compressor 2 to the subsequent burner 4.

[0046] Several embodiments of the burner 4 are disposed within the housing 20. For example... Figure 1As shown, multiple burners 4 can also be arranged in a ring around the rotor 8 within the housing 20. Fuel and compressed air generated by the compressor 2 are supplied to the burners 4, and combustion gas is generated as the working fluid of the turbine 6 by burning the fuel. Furthermore, the combustion gas is delivered from the burners 4 to the subsequent turbine 6. It should be noted that structural examples of the burners 4 in several embodiments will be described later.

[0047] Several embodiments of the turbine 6 include a turbine housing 22 and various blades disposed within the turbine housing 22. The various blades include multiple stationary blades 24 fixed to the side of the turbine housing 22 and multiple moving blades 26 installed on the rotor 8 in an alternating arrangement relative to the stationary blades 24. It should be noted that the turbine 6 may also include other components such as outlet guide vanes. In the turbine 6, combustion gas drives the rotor 8 to rotate via the multiple stationary blades 24 and the multiple moving blades 26. This drives a generator connected to the rotor 8.

[0048] An exhaust chamber 30 is connected to the downstream side of the turbine housing 22 via an exhaust chamber 28. The combustion gases after driving the turbine 6 are discharged to the outside through the exhaust chamber 28 and the exhaust chamber 30.

[0049] (Regarding burner 4)

[0050] Figure 2 This is a cross-sectional view showing several embodiments of the burner 4. Figure 3 This is a cross-sectional view showing the main parts of the burner 4 in several embodiments. Figure 4A This diagram schematically illustrates the configuration of each fuel injector when viewed from the downstream side to the upstream side along the axial direction of the burner 4 in several embodiments.

[0051] Reference Figure 2 , Figure 3 and Figure 4A The structure of burner 4 in several embodiments will be described.

[0052] like Figure 2 and Figure 3 As shown, in several embodiments, the burner 4 has multiple burners arranged in a ring around the rotor 8 (see reference). Figure 1 Each burner 4 includes: a burner bushing 46 disposed within a burner chamber 40 defined by the housing 20; and a first fuel injector 41 and a second fuel injector 42 respectively disposed within the burner bushing 46. In several embodiments, the first fuel injector 41 may be a main combustion burner 60, and the second fuel injector 42 may be a pilot combustion burner 50.

[0053] In the following description, the fuel F injected from the first fuel injector 41 is also referred to as the first fuel F1, and the fuel F injected from the second fuel injector 42 is also referred to as the second fuel F2.

[0054] The burner 4 also includes an outer cylinder 45 disposed on the outer periphery of the inner cylinder 47 of the burner bushing 46 inside the housing 20. An air passage 43 for compressed air to flow is formed on the outer periphery of the inner cylinder 47 and the inner periphery of the outer cylinder 45.

[0055] It should be noted that the burner 4 may also include other components such as a bypass pipe (not shown) for redirecting the combustion gases.

[0056] For example, the burner bushing 46 has: an inner cylinder 47 disposed around the pilot burner 50 and a plurality of main burners 60; and a tail cylinder 48 connected to the front end of the inner cylinder 47. That is, the burner bushing 46 corresponds to the combustion section for burning fuel F injected from the first fuel injector 41 and the second fuel injector 42.

[0057] like Figure 3 and Figure 4A As shown, the pilot burner 50 is arranged along the central axis of the burner bushing 46. Furthermore, a plurality of main burners 60 are arranged circumferentially, separated from each other, in a manner that surrounds the outer periphery of the pilot burner 50.

[0058] like Figure 3 As shown, the pilot burner 50 includes: a pilot nozzle (nozzle) 54 connected to a fuel port 52; an ignition burner tube 56 arranged to surround the pilot nozzle 54; and a plurality of swirlers (rotating plates) 58 disposed around the pilot nozzle 54.

[0059] The pilot nozzle 54 extends along the axial direction Da with the burner axis Ac as the center.

[0060] Here, the side extending from the burner axis Ac along the axial direction Da and upstream of the combustion gas flow is designated as the upstream side, and the other side extending downstream of the combustion gas flow is designated as the downstream side. Furthermore, the burner axis Ac is also the burner axis of the pilot burner 50.

[0061] An injection hole (not shown) for injecting fuel F (second fuel F2) is formed at the downstream end of the pilot nozzle 54. A plurality of rotating plates 58 are provided upstream of the location where the injection hole is formed by the pilot nozzle 54. Each rotating plate 58 is used to rotate compressed air about the burner axis Ac. Each rotating plate 58 extends from the outer periphery of the pilot nozzle 54 in a direction including a radial component, approaching the inner peripheral surface of the ignition burner nozzle 56. The ignition burner nozzle 56 has: a main body portion 56a located on the outer periphery of the pilot nozzle 54; and a conical portion 56b connected to the downstream side of the main body portion 56a and gradually increasing in diameter towards the downstream side. The plurality of rotating plates 58 approach the inner peripheral surface of the main body portion 56a in the ignition burner nozzle 56.

[0062] The main combustion burner 60 includes: a main nozzle (nozzle) 64 connected to a fuel port 62; a main burner cylinder 66 arranged to surround the main nozzle 64; an extension tube 65 connecting the main burner cylinder 66 to a burner bushing 46 (e.g., inner cylinder 47); and a swirler (rotating plate) 70 disposed on the outer periphery of the main nozzle 64.

[0063] The main nozzle 64 is a rod-shaped nozzle extending along the axial direction Da, centered on the burner axis Ab, which is parallel to the burner axis Ac. It should be noted that the burner axis Ab of the main combustion burner 60 is parallel to the burner axis Ac; therefore, the axial direction Da with respect to the burner axis Ac and the axial direction Da with respect to the burner axis Ab are in the same direction. Furthermore, the upstream side of the axial direction Da with respect to the burner axis Ac is the upstream side of the axial direction Da with respect to the burner axis Ab, and the downstream side of the axial direction Da with respect to the burner axis Ac is the downstream side of the axial direction Da with respect to the burner axis Ab.

[0064] An injection hole for injecting fuel F (first fuel F1) is formed at the middle portion of the main nozzle 64 along the axial direction Da. Multiple rotating plates 70 are disposed near the location where the injection hole is formed in the main nozzle 64. Each rotating plate 70 is used to rotate compressed air about the burner axis Ab. Each rotating plate 70 extends from the outer periphery of the main nozzle 64 in a direction including a radial component, and approaches the inner circumferential surface of the main burner cylinder 66. The main burner cylinder 66 is located on the outer periphery of the main nozzle 64.

[0065] In the burner 4 with the above structure, compressed air generated by the compressor 2 is supplied from the chamber inlet 40a into the burner chamber 40, and further flows from the burner chamber 40 into the ignition burner nozzle 56 and multiple main burner nozzles 66 via the air passage 43.

[0066] In the pilot burner 50, fuel F injected from the pilot nozzle 54 is sprayed together with compressed air from the downstream end of the ignition burner cylinder 56. The fuel F undergoes diffusion combustion within the burner bushing 46.

[0067] Right now, Figure 2 , Figure 3 and Figure 4A The pilot burner 50 (second fuel injector 42) shown is a diffusion combustion type fuel injector.

[0068] In the main combustion burner 60, compressed air inside the main burner cylinder 66 mixes with fuel F injected from the main nozzle 64 to form a premixed gas PM. The premixed gas PM is then ejected from the downstream end of the extension pipe 65 in the main combustion burner 60. The fuel F in this premixed gas PM undergoes premixed combustion within the burner bushing 46.

[0069] Right now, Figure 2 , Figure 3 and Figure 4A The main combustion burner 60 (first fuel injector 41) shown is a premixed combustion type fuel injector.

[0070] It should be noted that, alternatively, an injection hole for injecting fuel F can be formed in the rotary plate 70, from which fuel F is injected into the main burner cylinder 66. In this case, the portion corresponding to the rod-shaped main nozzle 64 described above forms a hub rod, and the main nozzle is formed having this hub rod and multiple rotary plates 70. Fuel F from the outside is supplied within the hub rod, and fuel F is supplied from the hub rod to the rotary plates 70.

[0071] Figure 4B This diagram schematically illustrates the arrangement of the fuel injectors 41, 42 when viewed from the downstream side to the upstream side along the axial direction of the burner 4 in other embodiments. Figure 4B In the burner 4 shown, the first fuel injector 41 and the second fuel injector 42 are arranged coaxially. Figure 4B The burner 4 shown is configured to inject first fuel F1 from around the second fuel injector 42.

[0072] exist Figure 4B In the burner 4 shown, the first fuel injector 41 and the second fuel injector 42 are arranged circumferentially inside the inner cylinder 47. Figure 4B In the burner 4 shown, both the first fuel injector 41 and the second fuel injector 42 can be premixed combustion type fuel injectors.

[0073] (Regarding fuel F)

[0074] For example, in gas turbines used for power generation, the operating mode is sometimes switched to reduced load operation to cope with the fluctuations in electricity demand between day and night. In reduced load operation, the flow rate of combustion gas through the turbine is reduced, causing the gas turbine to operate at a lower output than at rated operation.

[0075] If the output of a gas turbine is reduced by operating it under reduced load, the combustion temperature in the burner decreases, resulting in an increase in the production of unburned substances such as carbon monoxide and hydrocarbons, as well as combustion vibration. However, in order to flexibly respond to the aforementioned changes in electricity demand, efforts are being made to reduce the lower limit of the output during reduced load operation and thus expand the application range of gas turbines.

[0076] In order to reduce the lower limit of output during reduced load operation, it is preferable to mix and burn highly combustible fuels such as hydrogen, which have a relatively high combustion rate.

[0077] Therefore, in the burner 4 of several embodiments, the configuration is such that, as in conventional burners, natural gas can be used as fuel F, and any of hydrogen, propane, or a mixture of hydrogen and propane can be used as the high-combustibility fuel FH. It should be noted that in the following description, the case of using hydrogen as a high-combustibility fuel is given as an example. Furthermore, in the following description, natural gas, conventionally used as fuel F, is also referred to as low-combustibility fuel FL. That is, high-combustibility fuel FH is a fuel with a higher combustion rate than low-combustibility fuel FL. The combustion rate of fuel F referred to here is, for example, the combustion rate of a mixture of fuel F and air at an equivalence ratio of 1 under standard conditions (0°C, 1013 hPa).

[0078] Natural gas is used as a low-flammability fuel (FL), and any of hydrogen, propane, or a mixture of hydrogen and propane is used as a high-flammability fuel (FH), thereby suppressing the increase in the cost of fuel F.

[0079] (Regarding the fuel F supply system)

[0080] Figure 5 This is a schematic diagram showing the fuel supply system 200 of the burner 4 according to several embodiments. The gas turbine 1 according to several embodiments includes... Figure 5 The fuel F supply system 200 shown. Figure 5 The fuel F supply system 200 shown includes: an L1 supply line 211 for supplying low-flammability fuel FL to a first fuel injector 41; an L2 supply line 212 for supplying low-flammability fuel FL to a second fuel injector 42; an H1 supply line 221 for supplying high-flammability fuel FH to the first fuel injector 41; and an H2 supply line 222 for supplying high-flammability fuel FH to the second fuel injector 42.

[0081] L1 supply line 211 and H1 supply line 221 merge at confluence 231. The fuel supply line after confluence 231 is referred to as the first fuel supply line 201. The first fuel supply line 201 is connected to the fuel port 62 of the main nozzle 64, which is connected to the main combustion burner 60 (first fuel injector 41).

[0082] L2 supply line 212 and H2 supply line 222 merge at confluence 232. The fuel supply line after confluence 232 is referred to as the second fuel supply line 202. The second fuel supply line 202 is connected to the fuel port 52 of the pilot nozzle 44, which is connected to the pilot burner 50 (second fuel injector 42).

[0083] An L1 flow regulating unit 241 is provided on the L1 supply line 211 for regulating the supply of low-combustible fuel FL to the first fuel injector 41. An L2 flow regulating unit 242 is provided on the L2 supply line 212 for regulating the supply of low-combustible fuel FL to the second fuel injector 42.

[0084] An H1 flow regulating unit 243 is provided on the H1 supply line 221 for regulating the supply of highly combustible fuel FH to the first fuel injector 41. An H2 flow regulating unit 244 is provided on the H2 supply line 222 for regulating the supply of highly combustible fuel FH to the second fuel injector 42.

[0085] L1 flow regulating unit 241, L2 flow regulating unit 242, H1 flow regulating unit 243, and H2 flow regulating unit 244 are, for example, flow regulating valves.

[0086] exist Figure 5 In the fuel F supply system 200 shown, the low-flammability fuel flow regulating unit 240L, which independently regulates the supply of low-flammability fuel FL to the first fuel injector 41 and the second fuel injector 42, includes an L1 flow regulating unit 241 and an L2 flow regulating unit 242. Figure 5 In the fuel F supply system 200 shown, the high-combustibility fuel flow regulating unit 240H, which independently regulates the supply of high-combustibility fuel FH to the first fuel injector 41 and the second fuel injector 42, includes an H1 flow regulating unit 243 and an H2 flow regulating unit 244.

[0087] The L1 flow regulating unit 241, L2 flow regulating unit 242, H1 flow regulating unit 243, and H2 flow regulating unit 244 are controlled by a controller configured to control the low-combustibility fuel flow regulating unit 240L and the high-combustibility fuel flow regulating unit 240H. In several embodiments, this controller is implemented by the combustion control device 140 of the gas turbine 1.

[0088] That is, in several embodiments, the first ratio R1 of the highly combustible fuel FH to the total amount of the first fuel F1 injected by the first fuel injector 41, and the second ratio R2 of the highly combustible fuel FH to the total amount of the second fuel F2 injected by the second fuel injector 42 are controlled by the combustion control device 140. Details of the combustion control device 140 will be described later.

[0089] In the burner 4 of several embodiments, highly combustible fuels such as hydrogen with relatively high combustion rates, such as hydrogen, can be mixed and burned, thereby reducing the lower limit of the output of the gas turbine 1 during unloaded operation.

[0090] However, increasing the mixing ratio of the highly combustible fuel FH, i.e., the first ratio R1 and the second ratio R2, increases the risk of backfire. In other words, reducing the lower limit of output during reduced-load operation and reducing the risk of backfire are trade-offs.

[0091] On the other hand, the risk of backfire varies depending on the structure and location of the fuel injector, so the risk of backfire may not be the same for any given fuel injector. Specific examples are described below.

[0092] exist Figure 2 , Figure 3 and Figure 4A In the embodiment shown, the first fuel injector 41 is a premixed combustion fuel injector, and the second fuel injector 42 is a diffusion combustion fuel injector.

[0093] Generally speaking, diffusion combustion fuel injectors have a lower risk of backfire than premixed combustion fuel injectors. Therefore, in Figure 2 , Figure 3 and Figure 4A In the embodiment shown, the second fuel injector 42 is a burner with a lower risk of backfire than the first fuel injector 41.

[0094] It should be noted that, generally speaking, when a fuel injector is surrounded by multiple other fuel injectors, the risk of backfire in the fuel injector that is surrounded is lower than that in the fuel injector that surrounds it.

[0095] Here, in Figure 2 , Figure 3 and Figure 4A In the illustrated embodiment, a plurality of first fuel injectors 41 are arranged around the second fuel injector 42. Therefore, assuming that... Figure 2 , Figure 3 and Figure 4AIn the illustrated embodiment, both the first fuel injector 41 and the second fuel injector 42 are diffusion combustion or premixed combustion fuel injectors. If the fuel injector structures of the first fuel injector 41 and the second fuel injector 42 are the same, then the second fuel injector is a burner with a lower risk of backfire than the first fuel injector.

[0096] In addition, Figure 4B In the embodiment shown, the first fuel injector 41 is configured to be coaxially arranged with the second fuel injector 42, and injects the first fuel F1 from around the second fuel injector 42.

[0097] Generally speaking, when each fuel injector is configured such that one fuel injector is coaxially arranged with the other fuel injector, and the fuel injector of one fuel injector sprays fuel from around the fuel injector of the other fuel injector, the risk of backfire of the fuel injector of the other fuel injector is less than that of the fuel injector of one fuel injector.

[0098] Therefore, assuming as in Figure 4B In the illustrated embodiment, both the first fuel injector 41 and the second fuel injector 42 are diffusion combustion or premixed combustion fuel injectors. If the fuel injector structures of the first fuel injector 41 and the second fuel injector 42 are the same, then the second fuel injector 42 is a burner with a lower risk of backfire than the first fuel injector 41.

[0099] Therefore, in the burner 4 of several embodiments, taking into account the above situation, by changing the relative ratio R of the first ratio R1 and the second ratio R2, it is possible to reduce the lower limit of output during load reduction operation and reduce the risk of backfire.

[0100] That is, in the burner 4 of several embodiments, the combustion control device 140 is configured to control the low combustibility fuel flow regulating section 240L and the high combustibility fuel flow regulating section 240H according to the operating state of the gas turbine 1, so that the relative ratio R of the first ratio R1 and the second ratio R2 changes.

[0101] According to several embodiments, the burner 4 changes the ratio R according to the operating state of the gas turbine 1, thereby achieving both reducing the lower limit of output during load reduction operation and reducing the risk of backfire.

[0102] In a gas turbine 1 with a burner 4 having several implementations, it is possible to simultaneously reduce the lower limit of output during load reduction operation and reduce the risk of backfire, thereby expanding the application range of the gas turbine 1.

[0103] The following section provides a detailed explanation of the changes in the relative ratio R corresponding to the operating state of gas turbine 1.

[0104] Generally, the higher the load on the gas turbine 1, the greater the supply of fuel F, thus increasing the risk of backfire. Therefore, to avoid backfire, the ratio of highly combustible fuel FH to the total amount of fuel F injected by the fuel injectors is preferably reduced as the load on the gas turbine 1 increases. However, as mentioned above, the risk of backfire varies depending on the structure and location of the fuel injectors, so the risk of backfire may not be the same for any of the multiple fuel injectors. Therefore, as mentioned above, if the first fuel injector 41 is a combustor with a higher risk of backfire than the second fuel injector 42, it is preferable that the higher the load on the gas turbine, the greater the reduction in the first ratio R1 compared to the reduction in the second ratio R2. That is, preferably, the higher the load on the gas turbine 1, the smaller the value obtained by dividing the first ratio R1 by the second ratio R2 (the lower the load on the gas turbine 1, the larger the value obtained by dividing the first ratio R1 by the second ratio R2).

[0105] In the following explanation, the relative ratio R is the value obtained by dividing the first ratio R1 by the second ratio R2 (R = R1 / R2).

[0106] Figure 6A This is a chart illustrating an example of the relationship between the first ratio R1 and the second ratio R2 and an index representing the operating state of the gas turbine 1.

[0107] Figure 6B This is another example of a graph showing the relationship between the first ratio R1 and the second ratio R2 and an index representing the operating state of the gas turbine 1.

[0108] Figure 6C and Figure 6D This is a graph showing another example of the relationship between the first ratio R1 and an index representing the operating state of the gas turbine 1.

[0109] Figure 6E This is another example of a graph showing the relationship between the second ratio R2 and an index representing the operating state of the gas turbine 1.

[0110] It should be noted that, in Figures 6A to 6EIn this context, indicators representing the operating status of gas turbine 1 include, for example, the gas turbine inlet combustion gas temperature T1T, the dimensionless value of the gas turbine inlet combustion gas temperature T1T (CLCSO), and the load of gas turbine 1 (generator output: gas turbine output). It should be noted that the gas turbine inlet combustion gas temperature T1T is the temperature of the combustion gas at the inlet of turbine 6. CLCSO will be explained in detail later. Furthermore, the load of gas turbine 1 can be a measured value of the generator output, or a generator output command value transmitted from a central power supply center (not shown) that manages the generator outputs of multiple power generation devices.

[0111] That is, in several embodiments, the above-mentioned index can also be the gas turbine inlet combustion gas temperature T1T.

[0112] Generally speaking, the gas turbine inlet combustion gas temperature T1T is an indicator that more accurately represents the operating state of the gas turbine 1 compared to, for example, the load on the gas turbine 1. If the above indicator is the gas turbine inlet combustion gas temperature T1T, the above-mentioned ratio R can more accurately reflect the operating state of the gas turbine 1, thus improving the control accuracy of the above-mentioned ratio R.

[0113] In several implementations, the above-mentioned index can also be a dimensionless value obtained by making the gas turbine inlet combustion gas temperature T1T dimensionless (CLCSO).

[0114] As mentioned above, the gas turbine inlet combustion gas temperature T1T is an indicator that more accurately represents the operating state of the gas turbine 1 than, for example, the load of the gas turbine 1. However, in recent years, the gas turbine inlet combustion gas temperature T1T has become increasingly high, making it difficult to measure the gas turbine inlet combustion gas temperature T1T for extended periods.

[0115] If the above indicators are CLCSO, then there is no need to measure the gas turbine inlet combustion gas temperature T1T for a long time, which can easily improve the control accuracy of the above relative ratio R.

[0116] In several implementations, the above-mentioned indicators may also be the load of the gas turbine 1.

[0117] Although the load of gas turbine 1 is less accurate as an indicator of the operating status of gas turbine 1 compared to, for example, the gas turbine inlet combustion gas temperature T1T, the value of the load of gas turbine 1 is easier to obtain.

[0118] If the above indicators are the load of gas turbine 1, then the structure used to control the above relative ratio R can be simplified.

[0119] In the following description, an example is given where the indicator representing the operating state of the gas turbine 1 is CLCSO. However, the relationship between CLCSO and the first ratio R1 and the second ratio R2 described below also applies to the above-mentioned indicators other than CLCSO.

[0120] As mentioned above, generally speaking, the higher the load on gas turbine 1, the greater the supply of fuel F, thus increasing the risk of backfire. Therefore, it is preferable, for example, as... Figures 6A to 6D As shown, there is a tendency for the first ratio R1 to decrease as CLCSO increases.

[0121] It should be noted that the lower limit of the first ratio R1 can also be 0.

[0122] It should be noted that, as mentioned above, the second fuel injector 42 is a burner with a lower risk of backfire than the first fuel injector 41, therefore, for example... Figure 6A and Figure 6B As shown, regardless of the size of CLCSO, the second ratio R2 can be a constant value. It should be noted that, preferably, for example, as... Figure 6E As shown, there is a tendency for the second ratio R2 to decrease as CLCSO increases. In this case, the absolute value of the rate of change of the second ratio R2 relative to the change of CLCSO can also be smaller than the absolute value of the rate of change of the first ratio R1 relative to the change of CLCSO. That is, the decrease in the second ratio R2 when CLCSO increases can also be smaller than the decrease in the first ratio R1 when CLCSO increases.

[0123] As described above, the second fuel injector 42 is a burner with a lower risk of backfire than the first fuel injector 41, therefore, for example, Figure 6A and Figure 6B As shown, at least in regions where CLCSO is relatively large, the second ratio R2 can be larger than the first ratio R1, such as... Figure 6B As shown, regardless of the size of CLCSO, the second ratio R2 can be larger than the first ratio R1.

[0124] It could also be, such as Figure 6C and Figure 6D As shown, when CLCSO is within a certain range, the first ratio R1 remains constant regardless of the magnitude of CLCSO. Alternatively, for example, in... Figure 6C In the graph, as represented by the solid line, in the region where CLCSO is a relatively small value (e.g., above 0% and below b1%), the first ratio R1 remains constant regardless of the magnitude of CLCSO. Alternatively, for example, in... Figure 6DAs shown by the solid line in the graph, in the region where CLCSO is a relatively small value (e.g., above 0% and below b3%), the first ratio R1 becomes a constant value regardless of the magnitude of CLCSO.

[0125] Alternatively, it could be, for example, in Figure 6C As shown by the dashed line in the graph, in the region where CLCSO becomes a relatively large value (e.g., above b2% and below 100%), the first ratio R1 becomes a constant value regardless of the magnitude of CLCSO. Alternatively, for example, in... Figure 6D As shown by the solid line in the graph, in the region where CLCSO is a relatively large value (e.g., above 4% and below 100%), the first ratio R1 becomes a constant value regardless of the size of CLCSO.

[0126] It should be noted that, in Figure 6C In the case where b1 < b2, Figure 6D In, b3<b4.

[0127] It should be noted that, although not illustrated, it could also be, in Figure 6C In at least a portion of the region where the size of CLCSO is above b1% and below b2%, the first ratio R1 becomes a constant value regardless of the size of CLCSO. Similarly, it can also be that in Figure 6D In a region where the size of CLCSO is above b3% and below b4%, the first ratio R1 becomes a constant value regardless of the size of CLCSO.

[0128] Alternatively, although not illustrated, it could also be in Figure 6A or Figure 6B In the graph, in a portion of the graph, regardless of the size of CLCSO, there exists a portion where the first ratio R1 becomes the value.

[0129] Regarding the graph of the first ratio R1, it can be seen as follows: Figures 6A to 6C The graph shown, and in Figure 6D In a graph, lines can be represented by solid lines, or, for example, by straight lines. Figure 6D In addition to the dashed lines, graphs can also be represented by curves, or by straight lines and curves.

[0130] It should be noted that, at least in regions where CLCSO is relatively large, if the second ratio R2 is larger than the first ratio R1, then the second ratio R2 changes with respect to the change in CLCSO in the same way as the first ratio R1 changes with respect to the change in CLCSO described above.

[0131] The trends of change in the first ratio R1 and the second ratio R2 relative to CLCSO are summarized as follows.

[0132] In several embodiments of the burner 4, the first fuel injector 41 and the second fuel injector 42 are preferably set with a ratio R as follows: when the indicator representing the operating state (e.g., CLCSO) becomes a first value a1 (refer to...). Figure 6A and Figure 6B In the case of a first value a1, the load of the gas turbine 1 becomes a second value a2, which is a higher load than the first value a1 (see reference). Figure 6A and Figure 6B Compared to the case where the first ratio R1 is divided by the second ratio R2 (i.e., the value of R = R1 / R2 is larger), the value of the first ratio R1 is larger.

[0133] For example, such as Figures 6A to 6D As shown, there is a tendency for the first ratio R1 to decrease as CLCSO increases, such as... Figure 6A and Figure 6B As shown, regardless of the magnitude of CLCSO, if the second ratio R2 is a constant value, then when CLCSO is the first value a1, the value obtained by dividing the first ratio R1 by the second ratio R2 is larger compared to when CLCSO is the second value a2. It should be noted that, for example, as... Figure 6E As shown, even in the case where there is a tendency for the second ratio R2 to decrease as CLCSO increases, it is possible that when CLCSO becomes the first value a1, the value obtained by dividing the first ratio R1 by the second ratio R2 is larger than when CLCSO becomes the second value a2.

[0134] Therefore, the first fuel injector 41 is a burner with a higher risk of backfire than the second fuel injector 42. Thus, the aforementioned relative ratio R is preferred while taking into account both reducing the lower limit of output during reduced load operation and reducing the risk of backfire.

[0135] In several embodiments of the burner 4, the controller, i.e. the combustion control device 140, may also be configured to control the low-combustibility fuel flow regulating section 240L and the high-combustibility fuel flow regulating section 240H so that at least one of the first ratio R1 and the second ratio R2 is different when the above-mentioned index (e.g., CLCSO) is a first value a1 and when the above-mentioned index is a second value a2.

[0136] That is, when the above-mentioned indicator (e.g., CLCSO) is a first value a1 and when the above-mentioned indicator is a second value a2, by making at least one of the first ratio R1 and the second ratio R2 different, the above-mentioned relative ratio R can be made different when the above-mentioned indicator is a first value a1 and when the above-mentioned indicator is a second value a2.

[0137] In several embodiments of the burner 4, the controller, i.e. the combustion control device 140, may also be configured to control the low-combustibility fuel flow regulating section 240L and the high-combustibility fuel flow regulating section 240H so that the first ratio R1 becomes smaller when the above-mentioned index (e.g., CLCSO) becomes the second value a2, compared to the case where the above-mentioned index (e.g., CLCSO) becomes the first value a1.

[0138] Therefore, even if the load on the gas turbine 1 is relatively large, the risk of backfire in the first fuel injector 41, which is higher than that in the second fuel injector 42, can be suppressed.

[0139] In several embodiments of the burner 4, the controller, i.e. the combustion control device 140, may also be configured to control the low-combustibility fuel flow regulating section 240L and the high-combustibility fuel flow regulating section 240H so that when the above-mentioned index (e.g., CLCSO) becomes the second value a2, the second ratio R2 becomes the first ratio R1 or higher.

[0140] Therefore, the first fuel injector 41 is a burner with a higher risk of backfire than the second fuel injector 42. Thus, the risk of backfire in the first fuel injector 41 can be suppressed when the load on the gas turbine 1 becomes larger, and the second ratio R2 in the second fuel injector 42 can be made larger. For example, if the highly combustible fuel FH is a fuel with a relatively low environmental impact, such as hydrogen, the environmental impact can be suppressed by making the second ratio R2 larger.

[0141] In several embodiments of the burner 4, the controller, i.e. the combustion control device 140, may also be configured to control the low-combustibility fuel flow regulating section 240L and the high-combustibility fuel flow regulating section 240H so that when the above-mentioned index (e.g., CLCSO) becomes the second value a2, the second ratio R2 is 0.5 or more.

[0142] Therefore, when the load on the gas turbine 1 is relatively large, the second ratio R2 in the second fuel injector 42 can be made relatively large. For example, if the highly combustible fuel FH is a fuel with a relatively low environmental impact, such as hydrogen, the environmental impact can be suppressed by making the second ratio R2 relatively large.

[0143] (Regarding combustion control device 140)

[0144] Figure 7 This is an overall schematic diagram of the combustion control device 140 in several embodiments.

[0145] based on Figure 7The combustion control device 140 with several embodiments will be described. It should be noted that the processing functions of the combustion control device 140 are constituted by software (computer program) and executed by a computer, but it is not limited to this and can also be constituted by hardware.

[0146] like Figure 7 As shown, in several embodiments of the combustion control device 140, the inputs are a generator output command value from a central power supply center (not shown) and an IGV opening command value from an IGV control device (not shown). It should be noted that the generator output command value is not limited to being from a central power supply center; for example, it can be set by a generator output setter installed in the gas turbine generator set. Furthermore, here, the IGV opening command value is used as the IGV opening value for CLCSO calculation, but it is not necessarily limited to this; for example, the measured value can also be used if the IGV opening value has been measured.

[0147] Furthermore, in the combustion control device 140 of several embodiments, as described above, the following are input as measured values: generator output measured by power meter PW; intake air temperature measured by intake air thermometer Ta; low-combustible fuel temperature measured by low-combustible fuel gas thermometer Tfl; high-combustible fuel temperature measured by high-combustible fuel gas thermometer Tfh; exhaust temperature measured by exhaust temperature meter Th; intake air flow rate measured by intake air flow meter FX1; turbine bypass flow rate measured by turbine bypass flow meter FX2; intake air pressure measured by intake pressure gauge PX4; and engine compartment pressure measured by engine compartment pressure gauge PX5.

[0148] It should be noted that the turbine bypass flow rate is the flow rate of compressed air that flows in the turbine bypass line (not shown) without passing through the burner 4 and the turbine 6.

[0149] A turbine bypass valve (not shown) is installed on the turbine bypass line to adjust the turbine bypass flow rate of compressed air. This is for adjusting the outlet pressure (chamber pressure) of compressor 2, etc.

[0150] Furthermore, in the combustion control device 140 of several embodiments, based on these input signals, etc., the following are determined: L1 valve opening command value for adjusting the supply amount of low-combustible fuel FL to the first fuel injector 41; L2 valve opening command value for adjusting the supply amount of low-combustible fuel FL to the second fuel injector 42; H1 valve opening command value for adjusting the supply amount of high-combustible fuel FH to the first fuel injector 41; and H2 valve opening command value for adjusting the supply amount of high-combustible fuel FH to the second fuel injector 42.

[0151] The L1 valve opening command value is the valve opening command value in the L1 flow regulating unit 241, and the L2 valve opening command value is the valve opening command value in the L2 flow regulating unit 242. The H1 valve opening command value is the valve opening command value in the H1 flow regulating unit 243, and the H2 valve opening command value is the valve opening command value in the H2 flow regulating unit 244.

[0152] The opening command values ​​for valves L1, L2, H1, and H2 are calculated in such a way that CLCSO is related to the first ratio R1 and the second ratio R2 as described above.

[0153] In several embodiments of the burner 4, the supply of low-combustible fuel FL to the first fuel injector 41 is adjusted by setting the valve opening in the L1 flow regulating unit 241 to a valve opening corresponding to the L1 valve opening command value. Furthermore, in several embodiments of the burner 4, the supply of high-combustible fuel FH to the first fuel injector 41 is adjusted by setting the valve opening in the H1 flow regulating unit 243 to a valve opening corresponding to the H1 valve opening command value.

[0154] Therefore, low-flammability fuel FL and high-flammability fuel FH are supplied to the first fuel injector 41 at a first ratio R1 calculated and set by the combustion control device 140.

[0155] In several embodiments of the burner 4, the supply of low-combustible fuel FL to the second fuel injector 42 is adjusted by setting the valve opening in the L2 flow regulating unit 242 to a valve opening corresponding to the L2 valve opening command value. Furthermore, in several embodiments of the burner 4, the supply of high-combustible fuel FH to the second fuel injector 42 is adjusted by setting the valve opening in the H2 flow regulating unit 244 to a valve opening corresponding to the H2 valve opening command value.

[0156] Therefore, low-flammability fuel FL and high-flammability fuel FH are supplied to the second fuel injector 42 at a second ratio R2 calculated and set by the combustion control device 140.

[0157] (About CLCSO)

[0158] Figure 8 This is a block diagram illustrating the structure of the calculation logic of CLCSO in a combustion control device 140 according to several embodiments.

[0159] Combustion Load Command Value (CLCSO) is a parameter obtained by dimensionlessly converting the gas turbine inlet combustion gas temperature T1T, and is a parameter that has a positive correlation with the gas turbine inlet combustion gas temperature T1T (proportional to the gas turbine inlet combustion gas temperature T1T). The CLCSO is set to be 0% when the gas turbine inlet combustion gas temperature T1T is at the lower limit and 100% when the gas turbine inlet combustion gas temperature T1T is at the upper limit. For example, when the lower limit of the gas turbine inlet combustion gas temperature T1T is set to 700°C and the upper limit of the gas turbine inlet combustion gas temperature T1T is set to 1500°C, the CLCSO is expressed by the following equation (1).

[0160] CLCSO(%)={(Actual Output - 700℃MW) / (1500℃MW - 700℃MW)}×100…··(1)

[0161] It should be noted that the actual output is the measured value of the gas turbine output (generator output). 700℃ MW is the output of gas turbine 1 (generator output) at the current time when the gas turbine 1 is in the operating environment, with the gas turbine inlet combustion gas temperature T1T at the lower limit of 700℃. Conversely, 1500℃ MW is the output of gas turbine 1 (generator output) at the current time when the gas turbine 1 is in the operating environment, with the gas turbine inlet combustion gas temperature T1T at the upper limit of 1500℃.

[0162] based on Figure 8 The calculation logic of CLCSO is explained as follows: First, in function generator 151, based on the measured intake air temperature, IGV opening command value, and the turbine bypass ratio (turbine bypass flow / intake air flow) obtained by dividing the measured intake air flow (equivalent to the total compressed air volume) by the measured turbine bypass flow using divider 153, the value of 1500℃MW (temperature regulation MW) is calculated. That is, the value of 1500℃MW considering IGV opening, intake air temperature, and turbine bypass ratio is obtained.

[0163] In function generator 152, the value of 700℃MW is calculated based on the intake air temperature, IGV opening command value, and turbine bypass ratio. That is, the value of 700℃MW is obtained considering IGV opening, intake air temperature, and turbine bypass ratio.

[0164] In the divider 154, the measured intake pressure (atmospheric pressure) is divided by the standard atmospheric pressure set by the signal generator 161 to obtain the atmospheric pressure ratio (intake pressure / standard atmospheric pressure).

[0165] In multiplier 155, the value of 1500℃MW that takes into account atmospheric pressure ratio is obtained by multiplying the value of 1500℃MW obtained by function generator 151 with the atmospheric pressure ratio obtained by divider 154.

[0166] The 1500℃MW value obtained by multiplier 155 can be output to subtractor 157 via learning circuit 162, or directly to subtractor 157. It should be noted that learning circuit 162 is used to correct deviations in the 1500℃MW value caused by characteristic deterioration of gas turbine 1, etc.

[0167] In multiplier 156, the value of 700℃MW that takes into account atmospheric pressure ratio is obtained by multiplying the value of 700℃MW obtained by function generator 152 with the atmospheric pressure ratio obtained by divider 154.

[0168] In subtractor 157, the value of 700℃MW obtained by multiplier 156 is subtracted from the value of 1500℃MW obtained by multiplier 155 (or corrected by learning circuit 162) (1500℃MW-700℃MW: refer to equation (1) above).

[0169] In subtractor 158, the value of 700℃MW obtained by multiplier 156 is subtracted from the actual output, i.e. the measured value of generator output (gas turbine output) (actual output - 700℃MW: refer to equation (1) above).

[0170] Furthermore, in divider 159, the subtraction result of subtractor 158 is divided by the subtraction result of subtractor 157 (refer to equation (1) above). In this way, CLCSO can be calculated. It should be noted that if CLCSO is expressed as a percentage, simply multiply the output value of divider 159 by 100.

[0171] In the rate of change setter 160, the CLCSO changes slightly due to small fluctuations in the gas turbine output (generator output), etc. The valves used to regulate the fuel flow do not frequently repeat opening and closing actions. Therefore, the input value from the divider 159 is not immediately output as CLCSO, but is limited to the specified rate of increase or decrease.

[0172] This disclosure is not limited to the above-described embodiments, but also includes modifications to the above-described embodiments and appropriate combinations thereof.

[0173] The contents described in the above embodiments should be understood as follows.

[0174] (1) A gas turbine combustor 4 according to at least one embodiment of the present disclosure includes: a first fuel injector 41; a second fuel injector 42; a combustor bushing 46 as a combustion section, which combusts fuel F injected from the first fuel injector 41 and the second fuel injector 42; a low-combustibility fuel flow regulating section 240L, which independently regulates the supply amount of low-combustibility fuel FL to the first fuel injector 41 and the second fuel injector 42; a high-combustibility fuel flow regulating section 240H, which independently regulates the supply amount of high-combustibility fuel FH to the first fuel injector 41 and the second fuel injector 42, wherein the combustion rate of the high-combustibility fuel FH is higher than that of the low-combustibility fuel FL; and a combustion control device 140 as a controller. The controller (combustion control device 140) is configured to control the low-combustibility fuel flow regulating unit 240L and the high-combustibility fuel flow regulating unit 240H according to the operating state of the gas turbine 1, so that the ratio R of the first ratio R1 of the high-combustibility fuel FH to the total first fuel F1 injected by the first fuel injector 41 and the second ratio R2 of the high-combustibility fuel FH to the total second fuel F2 injected by the second fuel injector 42 changes.

[0175] According to the structure of (1) above, by making the above relative ratio R vary according to the operating state of the gas turbine 1, the lower limit of output during load reduction operation and the risk of backfire are both reduced.

[0176] (2) In several embodiments, based on the structure described in (1) above, the first fuel injector 41 and the second fuel injector 42 are set to the above-mentioned ratio R as follows: when the index representing the operating state becomes a first value a1, compared to the case where the load of the gas turbine 1 becomes a second value a2 which is a high load compared to the case where the first value a1 is a1, the value obtained by dividing the first ratio R1 by the second ratio R2 (i.e., the ratio R = R1 / R2) becomes larger.

[0177] Based on the structure of (2) above, the relative ratio R is set as follows: when the index representing the operating state becomes the first value a1, compared with the case where it becomes the second value a2, the value obtained by dividing the first ratio R1 by the second ratio R2 becomes larger. Therefore, if the first fuel injector 41 is a burner with a higher risk of backfire than the second fuel injector 42, the above relative ratio R is preferred on the basis of taking into account both reducing the lower limit of output during load reduction operation and reducing the risk of backfire.

[0178] (3) In several embodiments, the controller (combustion control device 140) may be configured to control the low-combustibility fuel flow regulating unit 240L and the high-combustibility fuel flow regulating unit 240H based on the structure of (2) above, so that at least one of the first ratio R1 and the second ratio R2 is different when the above index is the first value a1 and when the above index is the second value a2.

[0179] As in the structure of (3) above, when the above index becomes the first value a1 and when the above index becomes the second value a2, at least one of the first ratio R1 and the second ratio R2 is made different, thereby making the above relative ratio R different when the above index becomes the first value a1 and when the above index becomes the second value a2.

[0180] (4) In several embodiments, the controller (combustion control device 140) may be configured to control the low-combustibility fuel flow regulating unit 240L and the high-combustibility fuel flow regulating unit 240H based on the structure of (2) or (3) above, so that the first ratio R1 becomes smaller when the above index becomes the second value a2 compared to the case where the above index becomes the first value a1.

[0181] According to the structure described in (4) above, even if the load on the gas turbine 1 is relatively large, the risk of backfire in the first fuel injector 41 can be suppressed.

[0182] (5) In several embodiments, the controller (combustion control device 140) may be configured to control the low-combustibility fuel flow regulating unit 240L and the high-combustibility fuel flow regulating unit 240H based on any of the structures in (2) to (4) above, so that when the above-mentioned index becomes the second value a2, the second ratio R2 is greater than or equal to the first ratio R1.

[0183] Based on the structure described in (5) above, for example, if the first fuel injector 41 is a burner with a higher risk of backfire than the second fuel injector 42, then even under a relatively high load on the gas turbine 1, the risk of backfire in the first fuel injector 41 can be suppressed, and the second ratio R2 in the second fuel injector 42 can be made relatively large. For example, if the highly combustible fuel FH is a fuel with a relatively low environmental impact, such as hydrogen, then the environmental impact can be suppressed by making the second ratio R2 relatively large.

[0184] (6) In several embodiments, the controller (combustion control device 140) may be configured to control the low-combustibility fuel flow regulating unit 240L and the high-combustibility fuel flow regulating unit 240H based on any of the structures in (2) to (5) above, and the second ratio R2 is 0.5 or more when the above-mentioned index becomes the second value a2.

[0185] According to the structure described in (6) above, when the load on the gas turbine 1 is relatively large, the second ratio R2 in the second fuel injector 42 can be made relatively large. For example, if the highly combustible fuel FH is a fuel with a relatively low environmental impact, such as hydrogen, the environmental impact can be suppressed by making the second ratio R2 relatively large.

[0186] (7) In several embodiments, it is also possible that, based on any of the structures in (1) to (6) above, the first fuel injector 41 is a premixed combustion type fuel injector and the second fuel injector 42 is a diffusion combustion type fuel injector.

[0187] Generally speaking, diffusion combustion fuel injectors have a lower risk of backfire than premixed combustion fuel injectors.

[0188] According to the structure described in (7) above, the second fuel injector 42 is a burner with a lower risk of backfire than the first fuel injector 41.

[0189] (8) In several embodiments, it is also possible that, based on any of the structures in (1) to (7) above, a plurality of first fuel injectors 41 are arranged around the second fuel injector 42.

[0190] Generally speaking, when a fuel injector is surrounded by multiple other fuel injectors, the risk of backfire is lower for the fuel injectors that are surrounded by other fuel injectors than for the fuel injectors that are surrounded by other fuel injectors.

[0191] According to the structure described in (8) above, the second fuel injector 42 is a burner with a lower risk of backfire than the first fuel injector 41.

[0192] (9) In several embodiments, the first fuel injector 41 may be configured to be coaxially arranged with the second fuel injector 42, based on any of the structures in (1) to (7) above, and to inject the first fuel F1 from around the second fuel injector 42.

[0193] Generally speaking, when the fuel injectors of one party are coaxially arranged with the fuel injectors of the other party, and the fuel injectors of one party spray fuel from around the fuel injectors of the other party, the risk of backfire of the fuel injectors of the other party is smaller than that of the fuel injectors of one party.

[0194] According to the structure described in (9) above, the second fuel injector 42 is a burner with a lower risk of backfire than the first fuel injector 41.

[0195] (10) In several embodiments, it is also possible that, based on any of the structures in (1) to (9) above, the indicator representing the operating state is the gas turbine inlet combustion gas temperature T1T.

[0196] Generally speaking, the gas turbine inlet combustion gas temperature T1T is an indicator that more accurately represents the operating status of the gas turbine 1 than the load (gas turbine output) of the gas turbine 1.

[0197] Based on the structure of (10) above, the above-mentioned relative ratio R can more accurately reflect the operating state of the gas turbine 1, thus improving the control accuracy of the above-mentioned relative ratio R.

[0198] (11) In several embodiments, it is also possible that, based on any of the structures in (1) to (9) above, the index representing the operating state is the dimensionless value obtained by making the gas turbine inlet combustion gas temperature T1T (CLCSO).

[0199] As mentioned above, the gas turbine inlet combustion gas temperature T1T is, for example, an indicator that more accurately represents the operating state of the gas turbine 1 compared to the load (gas turbine output) of the gas turbine 1. However, in recent gas turbines, the gas turbine inlet combustion gas temperature T1T is high, making it difficult to measure the gas turbine inlet combustion gas temperature T1T for extended periods.

[0200] Based on the structure of (11) above, by setting the dimensionless value (CLCSO) of the gas turbine inlet combustion gas temperature T1T as the above index, the control accuracy of the above relative ratio R can be easily improved without long-term measurement of the gas turbine inlet combustion gas temperature T1T.

[0201] (12) In several embodiments, it is also possible that, based on any of the structures in (1) to (9) above, the indicator representing the operating state is the load of the gas turbine 1.

[0202] The load of gas turbine 1, for example, compared with the gas turbine inlet combustion gas temperature T1T, is an indicator of the operating status of gas turbine 1. Although the accuracy is poor, the value is relatively easy to obtain.

[0203] Based on the structure described in (12), by setting the load of the gas turbine 1 to the aforementioned index, the structure for controlling the aforementioned relative ratio R can be simplified.

[0204] (13) In several embodiments, it is also possible that, based on any of the structures in (1) to (12) above, the low-flammability fuel FL is natural gas and the high-flammability fuel FH is any of hydrogen, propane, and a mixture of hydrogen and propane.

[0205] As described in (13) above, the low-combustibility fuel FL can also be the usual fuel for the gas turbine 1, namely natural gas. In this case, the high-combustibility fuel FH can also be any of the following: a fuel with a higher combustion rate than natural gas, namely hydrogen, propane, or a mixture of hydrogen and propane. Thus, the increase in the cost of fuel F can be suppressed.

[0206] (14) The gas turbine 1 of at least one embodiment of the present disclosure has a gas turbine burner 4 with any of the structures in (1) to (13) above.

[0207] Based on the structure described above (14), it is possible to achieve both reducing the lower limit of output during load reduction operation and reducing the risk of backfire, thereby expanding the application range of the gas turbine 1.

[0208] Explanation of reference numerals in the attached figures:

[0209] 1...gas turbine;

[0210] 2...compressor;

[0211] 4...Gas turbine burner (combustion unit);

[0212] 6... Turbine;

[0213] 41...First fuel injector;

[0214] 42...Second fuel injector;

[0215] 46...burner bushing;

[0216] 50...pilot burner;

[0217] 60... Main combustion burner;

[0218] 140...combustion control device;

[0219] 200...supply system;

[0220] 240L...Low-combustible fuel flow regulating section;

[0221] 240H... High-combustible fuel flow regulating section.

Claims

1. A gas turbine burner, wherein, The gas turbine combustor includes: A first fuel injector injects fuel supplied from a first confluence of low-combustible fuel and high-combustible fuel with a combustion rate higher than that of the low-combustible fuel. A second fuel injector injects fuel supplied from a second confluence portion where the low-combustibility fuel and the high-combustibility fuel meet; A combustion section that burns the fuel injected from the first fuel injector and the second fuel injector; A low-combustible fuel flow regulating unit is used to independently regulate the supply of low-combustible fuel to the first fuel injector and the second fuel injector. A high-combustibility fuel flow regulating unit is used to independently regulate the supply of high-combustibility fuel to the first fuel injector and the second fuel injector; as well as The controller is configured to control the low-combustibility fuel flow regulating unit and the high-combustibility fuel flow regulating unit according to the operating state of the gas turbine, so as to change the ratio between a first ratio of the high-combustibility fuel to the total first fuel injected by the first fuel injector and a second ratio of the high-combustibility fuel to the total second fuel injected by the second fuel injector. The low-combustibility fuel flow regulating unit includes: A first low-flammability fuel flow regulating unit is used to regulate the supply of the low-flammability fuel to the first fuel injector; and The second low-flammability fuel flow regulating unit is used to regulate the supply of the low-flammability fuel to the second fuel injector. The high-combustibility fuel flow regulating unit includes: A first high-combustibility fuel flow regulating unit is used to regulate the supply of the high-combustibility fuel to the first fuel injector; and The second high-combustibility fuel flow regulating unit is used to regulate the supply of the high-combustibility fuel to the second fuel injector.

2. The gas turbine burner according to claim 1, wherein, The first fuel injector and the second fuel injector are set to the ratio as follows: when the index representing the operating state is a first value, the value obtained by dividing the first ratio by the second ratio is larger than the value obtained when the gas turbine load is high compared to the case where the index is a second value.

3. The gas turbine burner according to claim 2, wherein, The controller is configured to control the low-flammability fuel flow regulating unit and the high-flammability fuel flow regulating unit so that at least one of the first ratio and the second ratio is different when the index is the first value and when the index is the second value.

4. The gas turbine burner according to claim 2 or 3, wherein, The controller is configured to control the low-flammability fuel flow regulating unit and the high-flammability fuel flow regulating unit so that the first ratio decreases when the index is the second value, compared to when the index is the first value.

5. The gas turbine burner according to claim 2 or 3, wherein, The controller is configured to control the low-flammability fuel flow regulating unit and the high-flammability fuel flow regulating unit so that when the index becomes the second value, the second ratio is greater than or equal to the first ratio.

6. The gas turbine burner according to claim 2 or 3, wherein, The controller is configured to control the low-flammability fuel flow regulating unit and the high-flammability fuel flow regulating unit so that when the index becomes the second value, the second ratio is 0.5 or higher.

7. The gas turbine burner according to any one of claims 1 to 3, wherein, The first fuel injector is a premixed combustion type fuel injector. The second fuel injector is a diffusion combustion fuel injector.

8. The gas turbine burner according to any one of claims 1 to 3, wherein, A plurality of the first fuel injectors are arranged around the second fuel injector.

9. The gas turbine burner according to any one of claims 1 to 3, wherein, The first fuel injector is configured to be coaxially arranged with the second fuel injector, and injects the first fuel from around the second fuel injector.

10. The gas turbine burner according to any one of claims 1 to 3, wherein, The indicator representing the operating state is the gas turbine inlet combustion gas temperature.

11. The gas turbine burner according to any one of claims 1 to 3, wherein, The index representing the operating state is a value obtained by dimensionlessizing the gas turbine inlet combustion gas temperature.

12. The gas turbine burner according to any one of claims 1 to 3, wherein, The indicator representing the operating state is the load of the gas turbine.

13. The gas turbine burner according to any one of claims 1 to 3, wherein, The low-flammability fuel is natural gas. The highly combustible fuel is any one of hydrogen, propane, or a mixture of hydrogen and propane.

14. A gas turbine, wherein, The gas turbine includes the gas turbine burner as described in any one of claims 1 to 13.

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