Fuel gas composition analysis device and composition analysis method, and prime mover control device provided with the composition analysis device and prime mover control method including the composition analysis method

Abstract

A composition analysis device of fuel gas including a non-active gas and a combustible gas includes a heat generation amount measuring device that measures a heat generation amount per unit amount of the fuel gas, a density measuring device that measures a density of the fuel gas, and a control device that includes a composition calculation section that calculates a composition of the fuel gas using the heat generation amount measured by the heat generation amount measuring device and the density measured by the density measuring device.

Description

Technical Field

[0001] This disclosure relates to a composition analysis apparatus and method for fuel gas, as well as a prime mover control device equipped with the composition analysis apparatus and a prime mover control method including the composition analysis method.

[0002] This application claims priority based on Japan Patent Application No. 2020-181893, filed on October 29, 2020, the contents of which are incorporated herein by reference. Background Technology

[0003] When the fuel gas supplied to a gas turbine contains inert gases such as nitrogen, the concentration of these inert gases affects the combustibility of the fuel gas. Patent Document 1 describes a fuel flow control device that enables stable combustion of the fuel gas in a gas turbine even when the concentration of inert gases varies sequentially. In this fuel flow control device, the concentration of inert gases in the fuel gas is measured, and the fuel gas supply flow rate is controlled based on the measured concentration of inert gases.

[0004] Prior art literature

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2005-127197 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, gas chromatography is generally used to determine the concentration of inactive gases in fuel gas. However, since the detection time of gas chromatography is relatively long, there is a problem that it is difficult to control the fuel flow rate using the fuel flow control device described in Patent Document 1 when the concentration of inactive gases in fuel gas changes constantly.

[0009] In view of the above, the object of at least one embodiment of the present disclosure is to provide a fuel gas composition analysis apparatus and composition analysis method capable of rapidly analyzing the composition of fuel gas, as well as a prime mover control device equipped with the composition analysis apparatus and a prime mover control method including the composition analysis method.

[0010] Solution for solving the problem

[0011] To achieve the above objectives, the fuel gas composition analysis apparatus disclosed herein is a fuel gas composition analysis apparatus comprising inactive gases and combustible gases, wherein the fuel gas composition analysis apparatus includes: a calorific value measuring device that measures the calorific value per unit amount of the fuel gas; a density measuring device that measures the density of the fuel gas; and a control device including a composition calculation unit that uses the calorific value measured by the calorific value measuring device and the density measured by the density measuring device to calculate the composition of the fuel gas.

[0012] Furthermore, the fuel gas composition analysis method disclosed herein is a method for analyzing the composition of fuel gases including inactive gases and combustible gases. The method includes the following steps: measuring the calorific value per unit amount of the fuel gas; measuring the density of the fuel gas; and using the measured calorific value and the density to calculate the composition of the fuel gas.

[0013] Invention Effects

[0014] According to the fuel gas composition analysis apparatus and method disclosed herein, the calorific value per unit quantity and the density of the fuel gas can be measured rapidly, and the composition of the fuel gas can be analyzed using these measured values. Therefore, the composition of fuel gas containing both inactive and combustible gases can be analyzed rapidly. Attached Figure Description

[0015] Figure 1 This is a structural diagram of a fuel gas composition analysis apparatus and a prime mover control device equipped with the composition analysis apparatus according to one embodiment of the present disclosure.

[0016] Figure 2 This is a schematic diagram showing the structure of a gas turbine burner equipped with a fuel gas composition analysis device according to an embodiment of the present disclosure.

[0017] Figure 3 This is a schematic diagram of the control device included in a fuel gas composition analysis apparatus according to one embodiment of the present disclosure.

[0018] Figure 4 This is a diagram illustrating the principle of a fuel gas composition analysis apparatus according to an embodiment of the present disclosure, which calculates the composition of the fuel gas using the density and calorific value of the fuel gas.

[0019] Figure 5 This is a diagram illustrating another principle of the fuel gas composition analysis apparatus according to one embodiment of the present disclosure, which calculates the composition of the fuel gas using the density and calorific value of the fuel gas.

[0020] Figure 6This is a diagram illustrating an example of a control flow for calculating the fuel ratio based on the concentration of inert gases in the fuel gas and the calorific value of the fuel gas using a prime mover control device according to an embodiment of the present disclosure. Detailed Implementation

[0021] Hereinafter, the fuel gas composition analysis apparatus and composition analysis method according to embodiments of the present disclosure will be described with reference to the accompanying drawings. This embodiment represents one aspect of the present disclosure and does not limit the present disclosure; it can be modified arbitrarily within the scope of the technical concept of the present disclosure.

[0022] <Structure of a fuel gas composition analysis apparatus and a prime mover control device according to one embodiment of this disclosure>

[0023] like Figure 1 As shown, the fuel gas composition analysis apparatus 20 of one embodiment of this disclosure is used to analyze the composition of fuel gas supplied to a gas turbine 1, which serves as a prime mover. The fuel gas contains fuel components, such as combustible gases like hydrocarbon fuels, and inert gases like nitrogen. The composition of the fuel gas analyzed by the composition analysis apparatus 20 specifically refers to the concentration of inert gases, the concentration of combustible gases, or both. In the embodiments described below, the method of determining the concentration of inert gases in the fuel gas as a composition analysis will be explained, but it is essentially synonymous with determining the concentration of combustible gases, and determining the concentrations of both inert gases and combustible gases.

[0024] The gas turbine 1 includes: a compressor 2 for generating compressed air; a combustor 4 for generating combustion gases using compressed air and fuel gas; and a turbine 3 configured to rotate driven by the combustion gases. A generator 5 driven by the turbine 3 is connected to the turbine 3. The other end of a fuel supply line 6, one end of which is connected to a fuel supply source (not shown), is connected to the combustor 4.

[0025] like Figure 2 As shown, the burner 4 includes an outer cylinder 11, and inside the outer cylinder 11, an inner cylinder 12 is arranged at predetermined intervals radially centered on the axis of the outer cylinder 11. A tail cylinder 13 is connected to the front end of the inner cylinder 12. A passage for the compressor 2 (see reference) is formed between the outer cylinder 11 and the inner cylinder 12. Figure 1 The compressed air flows through an annular flow path 18. Inside the inner cylinder 12, there is a pilot burner 14 serving as a first burner, and a plurality of main burners 15 serving as second burners arranged to surround the pilot burner 14. The pilot burner 14 has a pilot nozzle 16 serving as a first nozzle, and each main burner 15 has a main nozzle 17 serving as a second nozzle.

[0026] like Figure 1 As shown, the analytical apparatus 20 includes: a density meter 21 and a calorific value meter 22, which are installed in the fuel supply line 6 to measure the density of the fuel gas and the calorific value per unit quantity (unit volume or unit mass, etc.) of the fuel gas, respectively; and a control device 23, which is electrically connected to the density meter 21 and the calorific value meter 22, respectively. The control device 23 inputs the measured values ​​of density ρ0 and calorific value LHV0 as electrical signals from the density meter 21 and the calorific value meter 22, respectively. The structure of the density meter 21 and the calorific value meter 22 is not particularly limited; any structure can be used as long as it can measure density and calorific value. Furthermore, the density meter 21 and the calorific value meter 22 can be separate independent devices, or they can be a single device capable of measuring both density and calorific value. As an example of the latter structure, an explosion-proof calorimeter can be used. Although the control device 23 is not shown in the figure, it includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), I / F (Interface), control circuits, etc., and is implemented by the CPU executing a specified control program stored in ROM.

[0027] A prime mover control device 30 can be installed in the gas turbine 1. This prime mover control device 30 controls the operation of the gas turbine 1 based on the composition of the fuel gas analyzed by the composition analysis device 20. The prime mover control device 30 includes the composition analysis device 20. In the embodiment described below, as a control of the operation of the gas turbine 1, the flow rate to the pilot nozzle 16 (see reference 1) is adjusted. Figure 2 ) and main nozzle 17 (refer to) Figure 2The method of describing the fuel-air ratio is exemplified by the ratio of supplied fuel gas to air, but it is not limited to this method. For example, as a control of the operation of the gas turbine 1, in order to eliminate poor combustion caused by inactive gases, the fuel-air ratio can be adjusted to be higher by switching control of multiple burners. In this embodiment, in the fuel supply line 6, downstream of the density meter 21 and the calorific value meter 22, a fuel ratio control unit 31 for adjusting the fuel ratio is provided as one of the components of the prime mover control device 30 (for example, a control valve that controls the flow rate of fuel gas supplied to the pilot nozzle 16 and the main nozzle 17, respectively). It should be noted that in this embodiment, the fuel ratio control unit 31 is provided outside the control device 23, for example as a control valve, but the adjustment of the fuel-air ratio can also be controlled by a program. Therefore, in this case, for example, the fuel ratio control unit 31 configured to control the fuel ratio by a program can be provided inside the control device 23. In this case, since the fuel ratio control unit 31 is installed in the control device 23, the number of components of the prime mover control device 30 can be reduced.

[0028] like Figure 3 As shown, the control device 23, a component of the composition analysis device 20, includes a composition calculation unit 24. This composition calculation unit 24 calculates the composition of the fuel gas using the density measured by the density measuring device 21 and the calorific value measured by the calorific value measuring device 22. Furthermore, when the prime mover control device 30, which includes the composition analysis device 20, is installed in the gas turbine 1, the control device 23 includes a fuel control unit 25. This fuel control unit 25 calculates a fuel control command for correcting the fuel ratio and outputs the fuel control command to the fuel ratio control unit 31.

[0029] Furthermore, outside the control device 23, in order to form a fuel ratio corresponding to the concentration of inert gases in the fuel gas, a fuel ratio control unit 31 is provided. This unit receives fuel control commands output from the fuel control unit 25 and controls the supply of fuel gas to the pilot nozzle 16 and the main nozzle 17. Here, the control device 23 is electrically connected to the fuel ratio control unit 31, and the fuel control commands are output to the fuel ratio control unit 31 as electrical signals.

[0030] In this embodiment, the example of providing the fuel ratio control unit 31 externally to the control device 23 is described. However, when the fuel ratio control unit 31 is provided internally to the control device 23, it can be separately provided from the fuel control unit 25 within the control device 23, or it can be provided independently within the fuel control unit 25. Furthermore, the fuel ratio control unit 31 can be an electronic component, an integrated program with the control device 23, or an integrated unit with the fuel control unit 25. It should be noted that when the fuel ratio control unit 31 is integrated with the program and either the control device 23 or the fuel control unit 25, the number of components in the control device 23 can be reduced, preventing the overall structure of the control device 23 from becoming overly complex. On the other hand, when the fuel ratio control unit 31 is provided independently as an electronic component, compared to being integrated as a program, it is possible to prevent multiple control units from malfunctioning simultaneously. Furthermore, in the event of a malfunction or when updating the control content, each component can be repaired or updated independently, thus improving operability.

[0031] Operation of a fuel gas composition analysis apparatus according to one embodiment of this disclosure

[0032] Next, the operation of the fuel gas composition analysis apparatus (fuel gas composition analysis method) according to one embodiment of this disclosure will be described. Figure 1 As shown, when the fuel gas supplied to the burner 4 flows in the fuel supply pipeline 6, the density ρ0 and the calorific value per unit volume LHV0 of the fuel gas are measured by the density meter 21 and the calorific value per unit volume, respectively. Data related to the measured density ρ0 and calorific value LHV0 are as follows: Figure 3 As shown, the data is transmitted to the composition calculation unit 24 of the control device 23. Hereinafter, the operation of the composition calculation unit 24 in calculating the composition of the fuel gas (the concentration C of inert gas in the fuel gas) using the measured density ρ0 and calorific value LHV0 will be described in detail.

[0033] In order to calculate the composition of the fuel gas, the composition calculation unit 24 requires, in addition to the density ρ0 and calorific value LHV0, the density ρ1 and calorific value per unit quantity of the combustible gas contained in the fuel gas, as well as the density ρ2 of the inert gas contained in the fuel gas. The combustible gas contains ethane, propane, etc., in addition to methane as its main component, and the density ρ1 varies depending on its composition. Furthermore, if the composition of the combustible gas changes, the calorific value LHV1 will naturally change as well. Therefore, for the combustible gas, the relationship between density ρ1 and calorific value LHV1 is predetermined through experiments, calculations, etc., and this relationship is stored in the composition calculation unit 24. Additionally, the density ρ2 of the inert gas also varies depending on the composition of the inert gas, but since this composition is usually known, the density ρ2 based on this composition is stored in the composition calculation unit 24. It should be noted that the density of a gas varies with its temperature and pressure. However, if the density does not change significantly during the operation of gas turbine 1 and can be assumed to be constant, the effects of temperature and pressure can be ignored. On the other hand, if the temperature and pressure changes during the operation of gas turbine 1 cannot be ignored, the relationship between the density ρ1 of the combustible gas and its calorific value LHV1 also includes the effects of temperature and pressure. The density ρ2 of the inactive gas can be set as a function related to temperature and pressure. The following explanation assumes that the temperature and pressure of the gas do not change significantly.

[0034] If the unit of the concentration C of the inactive gas in the fuel gas is set as mole fraction, then the relationship between the measured value of the density of the fuel gas ρ0, the density of the combustible gas contained in the fuel gas ρ1, and the density of the inactive gas contained in the fuel gas ρ2 is expressed by the following formula (1).

[0035] ρ2C+ρ1(1-C)=ρ0···(1)

[0036] In addition, inactive gases do not burn, so their calorific value is zero. Therefore, the relationship between the measured value of the calorific value of fuel gas LHV0 and the calorific value of combustible gas LHV1 is expressed by the following formula (2).

[0037] 0·C+LHV1(1-C)=LHV0···(2)

[0038] Formula (3) is derived from formula (2).

[0039] C=1-LHV0 / LHV1···(3)

[0040] Substituting formula (3) into formula (1), we get the following formula (4).

[0041] [Mathematical Expression 1]

[0042]

[0043] Here, the relationship between the density ρ1 and the calorific value LHV1 of the combustible gas stored in the calculation unit 24 is set as a linear regression function as shown in the following formula (5).

[0044] LHV1=αρ1+β···(5)

[0045] In formula (5), α and β are both constants.

[0046] Calculate LHV0 / LHV1 using formulas (4) and (5), and substitute it into formula (3) to obtain the following formula (6) for calculating the concentration C of inactive gas in fuel gas.

[0047] [Mathematical Expression 2]

[0048]

[0049] The composition calculation unit 24 calculates the concentration C of the inactive gas in the fuel gas based on formula (6) according to the density ρ0 and calorific value LHV0 measured by the density measuring device 21 and the calorific value measuring device 22 respectively, the density ρ2 of the inactive gas stored in the composition calculation unit 24, and the function shown in formula (5). That is, it calculates the composition of the fuel gas.

[0050] In this way, the calorific value (LHV0) and density (ρ0) of the fuel gas per unit quantity can be measured quickly, and these measured values ​​can be used to analyze the composition of the fuel gas. Therefore, it is possible to quickly analyze the composition of fuel gas containing both inactive and combustible gases.

[0051] like Figure 4 As shown, on the xy plane with density as the x-axis and calorific value as the y-axis, the function represented by formula (5) is the straight line L drawn with a solid line. Inert gases do not burn, so their calorific value is zero, therefore the ρ2 of the inert gas is located at point A on the x-axis. On the other hand, the density ρ1 and calorific value LHV1 of the combustible gas contained in the combustion gas are represented by point B on the straight line L. If the intersection point E is set as the straight line l1 drawn with a dashed line connecting points A and B, and the straight line l2 drawn with a dashed line parallel to the y-axis passing through point D which represents the measured value of the density of the fuel gas located on the x-axis, then the y-coordinate of the intersection point E represents the calorific value LHV0. On this xy plane, the concentration C of the inert gas in the fuel gas, with the unit set as mole fraction, is equivalent to the ratio of the length between points B and E to the length between points A and B.

[0052] When the concentration of inert gases in the fuel gas is as low as a few percent, the concentration C can be approximately calculated using a formula simpler than formula (6). When the concentration of inert gases in the fuel gas is low, such as... Figure 5 As shown, if point F is defined on the straight line L corresponding to the density ρ0 measured by the density measuring device 21, then point B is very close to point F. Therefore, if the calorific value corresponding to point F is defined as LHV1', then the calorific value LHV1' is approximately equal to the calorific value LHV1 corresponding to point B.

[0053] Here,

[0054] LHV1'=αρ0+β···(7)

[0055] Therefore, if LHV1' of the above formula (7) is used instead of LHV1 in formula (3), then formula (3) becomes the following formula (8).

[0056] [Mathematical Expression 3]

[0057]

[0058] It should be noted that, under such circumstances, the relationship between the density ρ1 and the calorific value LHV1 of the combustible gas is not limited to a linear regression function as shown in formula (5), but can be set as any function LHV1 = f(ρ1). Therefore, formula (7) becomes...

[0059] LHV1'=f(ρ0)···(7')

[0060] Formula (8) becomes Formula (9) below.

[0061] [Mathematical Expression 4]

[0062]

[0063] Thus, when the concentration of inactive gases in the fuel gas is low, the concentration C can be approximately calculated using the relatively simple formula (8) or (9) above, and the composition of fuel gas containing inactive and combustible gases can be easily analyzed.

[0064] <Operation of the prime mover control device according to one embodiment of this disclosure>

[0065] Next, the operation (prime mover control method) of a prime mover control device according to one embodiment of this disclosure will be described. Figure 3 As shown, the fuel control unit 25 receives data from the composition calculation unit 24 on the concentration C of the inert gas in the fuel gas and the calorific value LHV0 of the fuel gas per unit volume, and calculates the corresponding values ​​for the concentration C of the inert gas in the fuel gas, which are then directed to the pilot nozzle 16 (refer to the figure). Figure 2 ) and main nozzle 17 (refer to) Figure 2 The ratio of fuel gas supplied is called the fuel ratio.

[0066] exist Figure 6 The diagram illustrates an example of a control process by which the fuel control unit 25 calculates the fuel ratio based on the concentration C and the calorific value LHV0. In normal operation, a reference fuel ratio F0 corresponding to the output of the gas turbine 1 is determined. However, the fuel control unit 25 determines gains G1 and G2 based on the fuel ratios of the concentration C and calorific value LHV0, respectively, and calculates the fuel ratio F1 corresponding to the concentration C of the inactive gas in the fuel gas by adding these gains to the reference fuel ratio F0.

[0067] like Figure 3 As shown, the fuel control unit 25 calculates a fuel control command for controlling the fuel ratio control unit 31 to achieve the calculated fuel ratio, and outputs the fuel control command to the fuel ratio control unit 31. Thus, the fuel ratio control unit 31 controls the fuel supply to the pilot nozzle 16 and the main nozzle 17 at a fuel ratio corresponding to the concentration C of inert gases in the fuel gas, thereby ensuring stable combustion of the fuel gas even if the concentration C of inert gases in the fuel gas changes.

[0068] It should be noted that, in one embodiment of this disclosure, in order to calculate the concentration C of the inert gas in the fuel gas, the calculation unit 24 of the control device 23 continuously obtains the measured values ​​of density ρ0 and calorific value LHV0 measured by the density measuring device 21 and the calorific value measuring device 22, respectively. Accordingly, the concentration C of the inert gas in the fuel gas is appropriately digitized. Alternatively, the control device 23 may be pre-programmed to perform a series of processes for each predetermined period based on a predetermined period, thereby digitizing the concentration C of the inert gas in the fuel gas.

[0069] The contents described in the above embodiments shall be understood as follows.

[0070] [1] One proposed fuel gas composition analysis device is a fuel gas composition analysis device (20) that includes inactive gases and combustible gases.

[0071] The fuel gas composition analysis device includes:

[0072] A calorific value measuring device (22) for measuring the calorific value per unit amount of the fuel gas;

[0073] Density measuring device (21) for measuring the density of the fuel gas; and

[0074] The control device (23) includes a composition calculation unit (24) which calculates the composition of the fuel gas using the calorific value measured by the calorific value measuring device (22) and the density measured by the density measuring device (21).

[0075] According to the fuel gas composition analysis apparatus disclosed herein, the calorific value per unit quantity and the density of the fuel gas can be measured rapidly, and the composition of the fuel gas can be analyzed using these measured values. Therefore, the composition of fuel gas containing both inactive and combustible gases can be analyzed rapidly.

[0076] [2] The fuel gas composition analysis device of another scheme is based on the fuel gas composition analysis device of [1].

[0077] The control device (23) predefines a function representing the relationship between the calorific value LHV1 of the combustible gas per unit quantity and the density ρ1 of the combustible gas.

[0078] The composition calculation unit (24) uses the calorific value measured by the calorific value measuring device (22), the density measured by the density measuring device (21), and the function to calculate the composition of the fuel gas.

[0079] Based on this structure, the calorific value per unit volume of fuel gas and the density of fuel gas can be measured quickly, and these measured values ​​are used to analyze the composition of fuel gas. Therefore, the composition of fuel gas containing inert and combustible gases can be analyzed quickly. Moreover, by pre-defining a function that represents the relationship between the calorific value per unit volume of combustible gas and the density of combustible gas, it is possible to quickly grasp the situation even when the concentration of inert gases in fuel gas changes constantly.

[0080] [3] Another fuel gas composition analysis device is based on the fuel gas composition analysis device in [2].

[0081] The heat generation measured by the calorific value measuring device (22) is set as LHV0.

[0082] The density measured by the density measuring device (21) is set as ρ0.

[0083] Let the density of the inactive gas be ρ2.

[0084] Let the concentration of the inactive gas in the fuel gas be C.

[0085] When the function is set to LHV1 = αρ1 + β using constants α and β,

[0086] The composition calculation unit (24) calculates the concentration C of the inactive gas in the fuel as the composition of the fuel gas based on the following formula.

[0087] [Mathematical Expression 5]

[0088]

[0089] Based on this structure, by using the measured calorific value per unit of fuel gas and the density of fuel gas, the concentration C of inert gas is analyzed as a component of the fuel gas according to the above formula. Therefore, it is possible to accurately analyze the composition of fuel gas containing both inert and combustible gases.

[0090] [4] Another fuel gas composition analysis device is based on the fuel gas composition analysis device in [2].

[0091] The heat generation measured by the calorific value measuring device (22) is set as LHV0.

[0092] The density measured by the density measuring device (21) is set as ρ0.

[0093] Let the concentration of the inactive gas in the fuel gas be C.

[0094] When the function is set to LHV1 = f(ρ1),

[0095] The composition calculation unit (24) calculates the concentration C of the inactive gas in the fuel as the composition of the fuel gas based on the following formula, which uses f(ρ0) obtained by substituting μ0 into the variable ρ1 of the function.

[0096] [Mathematical Expression 6]

[0097]

[0098] Based on this structure, when the concentration C of the inert gas in the fuel gas is as low as a few percent, the concentration C can be approximately calculated using the relatively simple formula described above. Therefore, it is possible to easily analyze the composition of fuel gas containing both inert and combustible gases.

[0099] [5] Another fuel gas composition analysis device is based on the fuel gas composition analysis device in [4].

[0100] When the function is set to f(ρ1) = αρ1 + β using constants α and β,

[0101] The composition calculation unit (24) calculates the concentration C of the inactive gas in the fuel as the composition of the fuel gas based on the following formula (αρ0+β) obtained by substituting ρ0 into the variable ρ1 of the function.

[0102] [Mathematical Expression 7]

[0103]

[0104] Based on this structure, when the concentration C of the inactive gas in the fuel gas is as low as a few percent, the concentration C can be approximately calculated using a simpler formula than the formula of the structure described above [4]. Therefore, it is easier to analyze the composition of fuel gas containing both inactive and combustible gases.

[0105] [6] One embodiment of the prime mover control device is a prime mover control device (30) that controls a prime mover (gas turbine 1) equipped with a burner (4) for igniting the fuel gas.

[0106] The prime mover control device includes:

[0107] Any one of the components of the analysis device (20) from [1] to [5]; and

[0108] The fuel ratio control unit (31) is used to adjust the ratio of the fuel gas supplied to the first nozzle (pilot nozzle 16) and the second nozzle (main nozzle 17) of the burner (4), which are different from each other, i.e., the fuel ratio.

[0109] The control device (23) also includes a fuel control unit (25).

[0110] The fuel control unit (25) calculates a fuel control command for correcting the ratio of the fuel gas, i.e. the fuel ratio, based on the composition of the fuel gas obtained by the composition analysis device (20), and outputs the fuel control command to the fuel ratio control unit (31).

[0111] According to the prime mover control device disclosed herein, by rapidly analyzing the composition of the fuel gas containing inactive and combustible gases, the ratio of fuel gas supplied to the first and second nozzles of the burner, which are different from each other, is controlled, i.e., the fuel ratio, thereby maintaining appropriate combustion characteristics of the burner.

[0112] [7] One scheme's prime mover control device is based on the prime mover control device of [6].

[0113] The fuel ratio control unit (31) is located inside the control device (23) and is configured to receive the fuel control command and control the fuel ratio through a program.

[0114] With this structure, since the fuel ratio control unit is located inside the control device, the number of components in the prime mover control device can be reduced.

[0115] [8] One method for analyzing the composition of fuel gas is a method for analyzing the composition of fuel gas including inactive gases and combustible gases.

[0116] The method for analyzing the composition of the fuel gas includes the following steps:

[0117] The calorific value per unit volume of the fuel gas is measured;

[0118] Measure the density of the fuel gas; and

[0119] The composition of the fuel gas is calculated using the measured calorific value and density.

[0120] According to the fuel gas composition analysis method disclosed herein, the calorific value per unit quantity and the density of the fuel gas can be measured rapidly, and these measured values ​​are used to analyze the composition of the fuel gas. Therefore, it is possible to rapidly analyze the composition of fuel gas containing both inactive and combustible gases.

[0121] [9] The compositional analysis method for fuel gas in another scheme is based on the compositional analysis method for fuel gas in [8].

[0122] A function is predefined to represent the relationship between the calorific value LHV1 per unit quantity of the flammable gas and the density ρ1 of the flammable gas.

[0123] The composition of the fuel gas is calculated using the measured calorific value, the density, and the function.

[0124] According to this method, the calorific value per unit volume and the density of fuel gas can be measured quickly, and these measured values ​​are used to analyze the composition of fuel gas. Therefore, it is possible to quickly analyze the composition of fuel gas containing both inactive and combustible gases.

[0125]

[10] Another method for analyzing the composition of fuel gas is based on the method for analyzing the composition of fuel gas in [9].

[0126] The measured calorific value is set to LHV0.

[0127] Let the measured density be ρ0.

[0128] Let the density of the inactive gas be ρ2.

[0129] Let the concentration of the inactive gas in the fuel gas be C.

[0130] When the function is set to LHV1 = αρ1 + β using constants α and β,

[0131] The concentration C of the inactive gas in the fuel is calculated as the composition of the fuel gas based on the following formula.

[0132] [Mathematical Expression 8]

[0133]

[0134] Using this method, the calorific value per unit volume of fuel gas and the density of fuel gas are measured. Based on the above formula, the concentration C of inert gas is used as the composition of fuel gas for analysis. Therefore, it is possible to accurately analyze the composition of fuel gas containing both inert and combustible gases.

[0135]

[11] Another method for analyzing the composition of fuel gas is based on the method for analyzing the composition of fuel gas in [9].

[0136] The measured calorific value is set to LHV0.

[0137] Let the measured density be ρ0.

[0138] Let the concentration of the inactive gas in the fuel gas be C.

[0139] When the function is set to LHV1 = f(ρ1),

[0140] Based on the following formula, which uses f(ρ0) obtained by substituting ρ0 into the variable ρ1 of the function, the concentration C of the inactive gas in the fuel is calculated as the composition of the fuel gas.

[0141] [Mathematical Expression 9]

[0142]

[0143] According to this method, when the concentration C of inert gas in fuel gas is as low as a few percent, the concentration C can be approximately calculated using the simple formula described above. Therefore, it is possible to easily analyze the composition of fuel gas containing both inert and combustible gases.

[0144]

[12] Another method for analyzing the composition of fuel gas is based on the method for analyzing the composition of fuel gas in

[11] .

[0145] When the function is set to f(ρ1) = αρ1 + β using constants α and β,

[0146] Based on the following formula (αρ0+β) obtained by substituting ρ0 into the variable ρ1 of the function, the concentration C of the inactive gas in the fuel is calculated as the composition of the fuel gas.

[0147] [Mathematical Expression 10]

[0148]

[0149] According to this method, when the concentration C of the inert gas in the fuel gas is as low as a few percent, the concentration C can be approximately calculated using a simpler formula than the formula of the method described above

[11] . Therefore, it is easier to analyze the composition of fuel gas containing both inert and combustible gases.

[0150]

[13] One proposed prime mover control method is a prime mover control method that controls a prime mover (gas turbine 1) equipped with a burner (4) for igniting the fuel gas.

[0151] The prime mover control method includes any one of the component analysis methods from [8] to

[12] .

[0152] Based on the composition of the fuel gas obtained by the composition analysis method, a fuel control command is calculated and output. The fuel control command is used to correct the ratio of the fuel gas supplied to the different first nozzle (pilot nozzle 16) and second nozzle (main nozzle 17) of the burner (4), i.e., the fuel ratio.

[0153] According to the prime mover control method disclosed herein, by rapidly analyzing the composition of fuel gas containing inactive and combustible gases, the ratio of fuel gas supplied to the first and second nozzles of the burner, which are different from each other, is controlled, i.e., the fuel ratio, thereby maintaining appropriate combustion characteristics of the burner.

[0154] Explanation of reference numerals in the attached figures:

[0155] 1...Gas turbine (prime mover);

[0156] 4...burner;

[0157] 16... Pilot nozzle (first nozzle);

[0158] 17...Main nozzle (second nozzle);

[0159] 20...Composition of analytical apparatus;

[0160] 21... Density measuring device;

[0161] 22...calorific value measuring device;

[0162] 23...control device;

[0163] 24... constitutes the arithmetic unit;

[0164] 25... Fuel Control Section;

[0165] 30... Prime mover control device;

[0166] 31... Fuel ratio control unit.

Claims

1. A fuel gas composition analyzing device, the fuel gas comprising a non-active gas and a combustible gas, wherein the fuel gas composition analyzing device comprises: a heat generation amount measuring device that measures a heat generation amount per unit amount of the fuel gas; a density measuring device that measures a density of the fuel gas; and a control device that includes a composition calculating section that calculates a composition of the fuel gas using the heat generation amount measured by the heat generation amount measuring device and the density measured by the density measuring device, a function that represents a relationship of a heat generation amount per unit amount of the combustible gas LHV1 with respect to a density of the combustible gas pi is prescribed in advance in the control device, the heat generation amount measured by the heat generation amount measuring device is set as LHV0, the density measured by the density measuring device is set as p0, a density of the non-active gas is set as p2, a concentration of the non-active gas in the fuel gas is set as C, the function is set as LHV1 = ap1 + β using constants a and β, and the composition calculating section calculates the concentration C of the non-active gas in the fuel gas as the composition of the fuel gas based on the following equation, [Mathematical expression 1] C = (LHV0 - ap0 - β) / (a - p2) 2. A fuel gas composition analyzing device, the fuel gas comprising a non-active gas and a combustible gas, wherein the fuel gas composition analyzing device comprises: a heat generation amount measuring device that measures a heat generation amount per unit amount of the fuel gas; a density measuring device that measures a density of the fuel gas; and a control device that includes a composition calculating section that calculates a composition of the fuel gas using the heat generation amount measured by the heat generation amount measuring device and the density measured by the density measuring device, the heat generation amount measured by the heat generation amount measuring device is set as LHV0, the density measured by the density measuring device is set as p0, a concentration of the non-active gas in the fuel gas is set as C, the function is set as LHV1 = f(p1), and the composition calculating section calculates the concentration C of the non-active gas in the fuel gas as the composition of the fuel gas based on the following equation using f(p0) obtained by substituting p0 for a variable pi of the function, [Mathematical expression 2] C = f(p0) - p0 3. The fuel gas composition analyzing device according to claim 2, wherein the function is set as f(p1) = ap1 + β using constants a and β, and the composition calculating section calculates the concentration C of the non-active gas in the fuel gas as the composition of the fuel gas based on the following equation using (a p0 + β) obtained by substituting p0 for the variable pi of the function, [Mathematical expression 3] C = (LHV0 - a p0 - β) / (a - p2) 4. A prime mover control device that controls a prime mover that includes a combustor that combusts a fuel gas, wherein the prime mover control device comprises: the composition analyzing device according to any one of claims 1 to 3; and ​ ​ ​ ​ ​ ​ ​ ​ ​ 。 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 。 ​ ​ ​ ​ 。 ​ ​ ​ a fuel ratio control section for adjusting a ratio of the fuel gas supplied to mutually different first and second nozzles provided in the combustor, namely, a fuel ratio, the control device further includes a fuel control section, the fuel control section calculates a fuel control command for correcting the fuel ratio based on the composition of the fuel gas obtained by the composition analysis device, and outputs the fuel control command to the fuel ratio control section.

5. The prime mover control device according to claim 4, wherein the fuel ratio control section is provided inside the control device, and is configured to accept the fuel control command and control the fuel ratio by a program.

6. A fuel gas composition analysis method for a fuel gas containing a non-active gas and a combustible gas, wherein the fuel gas composition analysis method includes the following steps: measuring a calorific value per unit amount of the fuel gas; measuring a density of the fuel gas; and calculating a composition of the fuel gas using the measured calorific value and the density, a function representing a relationship of a calorific value LHV1 per unit amount of the combustible gas with respect to a density pi of the combustible gas is defined in advance, the measured calorific value is set as LHV0, the measured density is set as p0, a density of the non-active gas is set as p2, a concentration of the non-active gas in the fuel gas is set as C, the function is set as LHV1 = ap1 + β using constants a and β, the concentration C of the non-active gas in the fuel gas is calculated as the composition of the fuel gas based on the following equation, [mathematical expression 4] 。 7. A fuel gas composition analysis method for a fuel gas containing a non-active gas and a combustible gas, wherein the fuel gas composition analysis method includes the following steps: measuring a calorific value per unit amount of the fuel gas; measuring a density of the fuel gas; and calculating a composition of the fuel gas using the measured calorific value and the density, a function representing a relationship of a calorific value LHV1 per unit amount of the combustible gas with respect to a density pi of the combustible gas is defined in advance, the measured calorific value is set as LHV0, the measured density is set as p0, a concentration of the non-active gas in the fuel gas is set as C, the function is set as LHV1 = f(p1), the concentration C of the non-active gas in the fuel gas is calculated as the composition of the fuel gas based on the following equation using f(p0) obtained by substituting p0 into the variable pi of the function, [mathematical expression 5] 。 8. The fuel gas composition analysis method according to claim 7, wherein in a case where the function is set as f(p1) = ap1 + β using constants a and β, the concentration C of the non-active gas in the fuel gas is calculated as the composition of the fuel gas based on the following equation using (a p0 + β) obtained by substituting p0 into the variable pi of the function, [mathematical expression 6] 。 9. A prime mover control method that controls a prime mover that is provided with a combustor that combusts a fuel gas, wherein the prime mover control method includes the composition analysis method according to any one of claims 6 to 8, a fuel control command that is used to correct a ratio of the fuel gas that is supplied to mutually different first and second nozzles that are provided in the combustor, that is, a fuel ratio, is calculated and outputted on the basis of the composition of the fuel gas that is obtained by the composition analysis method.

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