Gas turbine control device and gas turbine control method

Abstract

To suppress occurrence of overshoot in a control parameter and deterioration of performance of a gas turbine.SOLUTION: A gas turbine control device for controlling a gas turbine operable using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying second fuel is connected to a first fuel flow path through which first fuel flows calculates a control parameter for controlling the gas turbine by adding a correction value calculated based on a result obtained by applying a delay time to a second flow rate detected by a second flowmeter provided in the second fuel flow path to a basic control value calculated based on a first flow rate of the fuel supplied to the gas turbine. The delay time includes a first delay time obtained by dividing a first pipe volume from an installation position of the second flowmeter to a merging position of the second fuel flow path with respect to the first fuel flow path by the second flow rate, and a second delay time obtained by dividing a second pipe volume from the merging position to the gas turbine by the first flow rate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a gas turbine control device and a gas turbine control method. [Background technology]

[0002] In a steelmaking plant, by-product gases such as blast furnace gas (BFG), Linz-Donawitz converter gas (LDG), finex off gas (FOG), and coke oven gas (COG) are emitted during the process of obtaining iron by reducing iron ore using fossil fuels. Patent Document 1 discloses a technology relating to a gas turbine that uses, as fuel, the by-product gases emitted from such steelmaking plants. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-229919 Summary of the Invention [Problem to be solved by the invention]

[0004] As mentioned above, there are various types of by-product gases discharged from steelmaking plants. While Patent Document 1 uses one type of by-product gas as fuel for the gas turbine, a mixed gas containing multiple types of by-product gases can also be used. For example, a second fuel, which is another by-product gas discharged from the steelmaking plant, can be mixed as needed into a fuel flow path that supplies blast furnace gas as the main first fuel to the gas turbine. In this case, the composition of the mixed gas changes depending on the flow rate of the second fuel, changing the characteristics of the fuel supplied to the gas turbine and affecting the combustion state (temperature, pressure, etc.) of the gas turbine. Therefore, when the characteristics of the fuel supplied to the gas turbine change, it is desirable to correct the control parameters of the gas turbine depending on the flow rate of the second fuel in order to achieve a combustion state appropriate for the changed fuel characteristics.

[0005] The flow rate of the second fuel mixed with the first fuel can be detected, for example, by a flow meter installed in the fuel flow path through which the second fuel flows. However, the flow rate measurement value of the second fuel detected by this flow meter includes a measurement delay by the flow meter and a delay time including the time required for the second fuel to pass through the flow meter and reach the gas turbine. Therefore, if the control parameters described above are corrected based on the flow rate measurement value of the second fuel detected by such a flow meter, the control parameters may be corrected at a time when the second fuel passing through the flow meter has not actually reached the gas turbine, which may result in overshoot of the control parameters and a deterioration in gas turbine performance. In particular, if the steel plant from which the by-product gas is discharged is located far from the gas turbine, the length of the piping through which the by-product gas passes is also long, which increases the impact of such delay time.

[0006] At least one embodiment of the present disclosure has been made in consideration of the above-described circumstances, and has an object to provide a gas turbine control device and a gas turbine control method that are capable of suppressing the occurrence of overshoot in control parameters and degradation of gas turbine performance by correcting control parameters at appropriate timing in accordance with changes in the characteristics of fuel supplied to the gas turbine. [Means for solving the problem]

[0007] In order to solve the above problem, a gas turbine control device according to an embodiment of the present disclosure includes: A gas turbine control device for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from the first fuel is connected to a first fuel flow path through which the first fuel flows, a first flow meter provided in the first fuel flow path for detecting a first flow rate of the fuel; a second flow meter provided in the second fuel flow path for detecting a second flow rate of the second fuel; a gas turbine control unit that calculates a control parameter for controlling the gas turbine by adding a correction value calculated based on a result of applying a delay time to the second flow rate detected by the second flow meter to a basic control value calculated based on the first flow rate; and Equipped with The delay time is a first delay time obtained by dividing a first piping volume from an installation position of the second flow meter to a joining position of the second fuel flow path with the first fuel flow path by the second flow rate; a second delay time obtained by dividing a second piping volume from the joining position to the gas turbine by the first flow rate; Includes.

[0008] To solve the above-described problems, a gas turbine control device according to another embodiment of the present disclosure is a gas turbine control device for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel is connected to a first fuel flow path through which the first fuel flows, a first flow meter provided in the first fuel flow path for detecting a first flow rate of the fuel; a second flow meter provided in the second fuel flow path for detecting a second flow rate of the second fuel; a gas turbine control unit that calculates a control parameter for controlling the gas turbine by adding a correction value corresponding to a value of the second flow rate after the change to a basic control value calculated based on the first flow rate when the second flow rate changes; and Equipped with The gas turbine control unit adds the correction value to the basic control value during a period of change in the second flow rate to which a preset delay time is applied.

[0009] In order to solve the above problem, a gas turbine control method according to an embodiment of the present disclosure includes: 1. A gas turbine control method for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel is connected to a first fuel flow path through which the first fuel flows, the method comprising: a detector disposed in the first fuel flow path and detecting a first flow rate of the fuel; a second flow rate detector provided in the second fuel flow path and detecting a second flow rate of the second fuel; calculating a control parameter for controlling the gas turbine by adding a correction value calculated based on a result of applying a delay time to the second flow rate detected by the second flow meter to a basic control value calculated based on the first flow rate; Equipped with The delay time is a first delay time obtained by dividing a first piping volume from an installation position of the second flow meter to a joining position of the second fuel flow path with the first fuel flow path by the second flow rate; a second delay time obtained by dividing a second piping volume from the joining position to the gas turbine by the first flow rate; Includes.

[0010] In order to solve the above problem, a gas turbine control method according to an embodiment of the present disclosure includes: 1. A gas turbine control method for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel is connected to a first fuel flow path through which the first fuel flows, the method comprising: a detector disposed in the first fuel flow path and detecting a first flow rate of the fuel; a second flow rate detector provided in the second fuel flow path and detecting a second flow rate of the second fuel; calculating a control parameter for controlling the gas turbine by adding a correction value corresponding to a value of the second flow rate after the change to a basic control value calculated based on the first flow rate when the second flow rate changes; Equipped with The correction value is added to the basic control value during a period of change in the second flow rate to which a preset delay time is applied. [Effects of the Invention]

[0011] According to at least one embodiment of the present disclosure, it is possible to provide a gas turbine control device and a gas turbine control method that can suppress the occurrence of overshoot in the control parameters and degradation of the performance of the gas turbine by correcting the control parameters at an appropriate timing in accordance with changes in the properties of the fuel supplied to the gas turbine. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is an overall configuration diagram of a gas turbine facility including a gas turbine control device according to an embodiment; [Figure 2] FIG. 1 is a block diagram of a gas turbine control device according to a reference technique. [Figure 3] 3 is a diagram illustrating an example of gas turbine control performed by the gas turbine control device according to the reference technique shown in FIG. 2. FIG. [Figure 4] FIG. 1 is a block diagram of a gas turbine control device according to a first embodiment. [Figure 5] 5 is a diagram illustrating an example of gas turbine control performed by the gas turbine control device of FIG. 4. [Figure 6]FIG. 5 is a block diagram of a gas turbine control device according to a second embodiment. [Figure 7] FIG. 7 is a diagram illustrating an example of gas turbine control performed by the gas turbine control device of FIG. 6. [Figure 8] This is a modification of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, several embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the configurations described as embodiments or shown in the drawings are merely illustrative examples and are not intended to limit the scope of the present disclosure.

[0014] 1 is an overall configuration diagram of a gas turbine facility 1 including a gas turbine control device 100 according to one embodiment. The gas turbine facility 1 includes a gas turbine 3 to be controlled, and the gas turbine control device 100 for controlling the gas turbine 3.

[0015] The gas turbine 3 is a gas turbine device that can be operated using fuel F supplied from a fuel supply system 2. The detailed configuration of the gas turbine 3 is not shown in FIG. 1 following a known example, but briefly described, the gas turbine 3 generates combustion gas by mixing and burning the fuel F supplied from the fuel supply system 2 with compressed air generated by a compressor (not shown), and drives a turbine with the combustion gas to obtain power. When a generator is connected to the output shaft of the turbine, the rotational energy of the turbine can be converted into electrical energy to generate power.

[0016] The fuel supply system 2 is configured to supply a fuel F to the gas turbine 3. The fuel supply system 2 has a first fuel supply source 4 and a second fuel supply source 6 that can supply, as the fuel F, a first fuel F1 and a second fuel F2, respectively.

[0017] The first fuel F1 and the second fuel F2 are different types of fuel gases, each of which is a by-product gas emitted in a process of obtaining iron by reducing iron ore using fossil fuels in a steelmaking plant. The first fuel F1 and the second fuel F2 can be arbitrarily selected from several examples of such by-product gases, such as blast furnace gas (BFG), Linz-Donawitz converter gas (LDG), finex off gas (FOG), and coke oven gas (COG). In the following description, unless otherwise specified, the first fuel F1 is blast furnace gas and the second fuel F2 is converter gas, but the present invention is not limited thereto.

[0018] A first fuel flow path 8 for supplying a first fuel F1 is connected to the first fuel supply source 4, and a second fuel flow path 10 for supplying a second fuel F2 is connected to the second fuel supply source 6. The first fuel flow path 8 and the second fuel flow path 10 join together at a joining position 12 located downstream of each other. The joining position 12 is connected via a mixing flow path 14 to the gas turbine 3, which is the supply destination of the fuel F.

[0019] The mixing passage 14 is provided with a first flow meter 16 for detecting the flow rate of the fuel F supplied to the gas turbine 3 (hereinafter referred to as the "first flow rate FR1" as appropriate). The second fuel passage 10 is provided with a second flow meter 18 for detecting the flow rate of the second fuel F2 (hereinafter referred to as the "second flow rate FR2" as appropriate). The gas turbine 3 is also provided with an exhaust gas temperature sensor 19 for detecting the temperature Te of the exhaust gas, which is the combustion gas after driving the turbine. The detected values ​​of the first flow meter 16, the second flow meter 18, and the exhaust gas temperature sensor 19 are sent to the gas turbine control device 100 as electric signals, and can be used for various calculations.

[0020] The gas turbine control device 100 is a control unit for controlling the gas turbine 3 having the above-described configuration, and is configured with, for example, a central processing unit (CPU), a random access memory (RAM), a read-only memory (ROM), and a computer-readable storage medium. A series of processes for realizing various functions is stored in a storage medium or the like in the form of a program, for example. The CPU reads the program into the RAM or the like and executes information processing and arithmetic operations to realize various functions. The program may be pre-installed in a ROM or other storage medium, provided in a state stored in a computer-readable storage medium, or distributed via wired or wireless communication means. Examples of computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories.

[0021] In the gas turbine control device 100, a pre-installed program is executed, thereby performing arithmetic processing for controlling the gas turbine 3. In this arithmetic processing, the detection values ​​of the first flow meter 16, the second flow meter 18, and the exhaust gas temperature sensor 19 are input, and the arithmetic processing is performed by sending a control parameter Pc calculated as the calculation result to the gas turbine 3, thereby controlling the gas turbine 3.

[0022] Here, gas turbine control according to the reference technology will be described. Fig. 2 is a block diagram of a gas turbine control device 100 according to the reference technology. The gas turbine control device 100 includes a first flow rate obtaining unit 102, a second flow rate obtaining unit 104, a target exhaust gas temperature calculating unit 106, a correction value calculating unit 108, an exhaust gas temperature obtaining unit 110, and a control parameter calculating unit 112.

[0023] The first flow rate obtaining unit 102 is configured to obtain a first flow rate FR1 detected by a first flow meter 16 installed in the mixing flow path 14. This first flow rate FR1 is the total flow rate of the fuel F supplied to the gas turbine 3, and is input to a target exhaust gas temperature calculating unit 106.

[0024] The target exhaust gas temperature calculation unit 106 is configured to calculate a target exhaust gas temperature Te0 based on the first flow rate FR1 input from the first flow rate acquisition unit 102. The target exhaust gas temperature Te0 is an exhaust gas temperature Te at which the turbine inlet temperature of the gas turbine 3 reaches a predetermined value (e.g., 1000°C) when the fuel F supplied to the gas turbine 3 is only the first fuel F1 (i.e., when the supply amount of the second fuel F2 is zero), and is calculated based on the first flow rate FR1. In the target exhaust gas temperature calculation unit 106, a relationship between the first flow rate FR1 and the target exhaust gas temperature Te0 is prepared in advance as correlation data, and the target exhaust gas temperature Te0 corresponding to the first flow rate FR1 input from the first flow rate acquisition unit 102 is calculated based on the correlation data.

[0025] The second flow rate obtaining unit 104 is configured to obtain the second flow rate FR2 detected by the second flow meter 18 installed in the second fuel flow path 10. The second flow rate FR2 obtained by the second flow rate obtaining unit 104 is input to a correction value calculation unit 108. The correction value calculation unit 108 calculates a correction value Tamd for correcting the target exhaust gas temperature Te0 according to the second flow rate FR2.

[0026] As described above, the target exhaust gas temperature Te0 is calculated as a target value for setting the turbine inlet temperature to a predetermined value when the fuel F supplied to the gas turbine 3 is only the first fuel F1 (i.e., when the second flow rate FR2 is zero). Therefore, when the second fuel F2 is mixed with the fuel F (i.e., when the second flow rate FR2 is not zero), the target exhaust gas temperature Te0 is corrected by adding a correction value Tamd corresponding to a change in the composition of the fuel F due to the second fuel F2. For example, when the first fuel F1, which is blast furnace gas (BFG), is mixed with the second fuel F2, which is converter furnace gas (LDG) with a high calorific value, the calorific value of the fuel F supplied to the gas turbine 3 increases, thereby raising the exhaust gas temperature Te of the gas turbine 3. In this case, if the target exhaust gas temperature Te0 is kept constant, the turbine inlet temperature will drop from the predetermined value, resulting in a performance degradation of the gas turbine 3. Therefore, by adding the correction value Tamd calculated based on the second flow rate FR2 of the second fuel F2 to the target exhaust gas temperature Te0 to perform correction, the turbine inlet temperature can be appropriately maintained even if a change in the composition of the fuel F occurs.

[0027] The target exhaust gas temperature Te0 calculated by the target exhaust gas temperature calculation unit 106 is corrected by adding the correction value Tamd calculated by the correction value calculation unit 108 to obtain the corrected target exhaust gas temperature Te0'. The control parameter calculation unit 112 calculates a control parameter Pc for the gas turbine 3 based on the difference ΔTe between the exhaust gas temperature Te acquired by the exhaust gas temperature acquisition unit 110 and the corrected target exhaust gas temperature Te0'.

[0028] Here, the behavior of the gas turbine 3 controlled by the gas turbine control device 100 according to the reference technology having the above configuration will be described. Fig. 3 is a diagram showing an example of control of the gas turbine 3 by the gas turbine control device 100 according to the reference technology shown in Fig. 2.

[0029] In this control example, the second flow rate FR2 detected by the second flow meter 18 monotonically increases from time t1 to time t2, is kept constant from time t2 to time t3, and monotonically decreases from time t3 to time t4. At this time, the correction value Tamd calculated by the correction value calculation unit 108 also monotonically increases from time t1 to time t2, is kept constant from time t2 to time t3, and monotonically decreases from time t3 to time t4, corresponding to the second flow rate FR2. That is, in the control example of the reference technology, the correction value Tamd behaves such that it increases and decreases at the same timing as the second flow rate FR2 detected by the second flow meter 18.

[0030] However, in the actual fuel supply system 2, a delay time tr is required in no small measure from the time the second fuel F2 passes through the second flow meter 18 in the second fuel flow path 10 until it reaches the gas turbine 3. Therefore, the flow rate FR2' of the second fuel F2 that actually reaches the inlet of the gas turbine 3 behaves with a delay of the delay time tr from the second flow rate FR2, which is the detection value of the second flow meter 18. Therefore, it is desirable that the ideal correction value Tamd (hereinafter referred to as "ideal correction value Tamd'") that is added to the target exhaust gas temperature Te0 in order to maintain the turbine inlet temperature of the gas turbine 3 at a predetermined value when the second fuel F2 is supplied is delayed by the delay time tr from the correction value Tamd calculated by the correction value calculation unit 108 based on the second flow rate FR2 (see the dashed dotted line in the lower graph of FIG. 3 ).

[0031] Comparing the correction value Tamd with the ideal correction value Tamd', it is shown that when the second fuel F2 increases, the correction value Tamd is larger than the ideal correction value Tamd', which may result in an overshoot in the turbine inlet temperature of the gas turbine 3. On the other hand, when the second fuel F2 decreases, the correction value Tamd is smaller than the ideal correction value Tamd', which may result in a performance degradation in the gas turbine 3. These problems with the reference technology can be preferably solved by the following embodiments.

[0032] Fig. 4 is a block configuration diagram of a gas turbine control device 100 according to the first embodiment, and Fig. 5 is a diagram showing an example of control of a gas turbine 3 by the gas turbine control device 100 of Fig. 4. The gas turbine control device 100 according to the first embodiment differs from the above-described reference technology in that it further includes a delay time calculation unit 114.

[0033] The delay time calculation unit 114 is configured to calculate a delay time tr required for the second fuel F2 that has passed through the second flow meter 18 to reach the gas turbine 3. The calculation of the delay time tr by the delay time calculation unit 114 may include, for example, calculation of a first delay time tr1 and a second delay time tr2. Specifically, the first delay time tr1 can be calculated by the following equation by dividing the first piping volume V1 from the installation position of the second flow meter 18 to the junction position 12 by the second flow rate FR2 detected by the second flow meter 18. tr1=V1 / FR2 (1) The second delay time tr2 is calculated by dividing the second piping volume V2 from the joining position 12 to the gas turbine 3 by the first flow rate FR1 detected by the first flow meter 16 using the following equation. tr2=V2 / FR1 (2) Then, the delay time calculation unit 114 calculates the delay time tr by the following equation using the first delay time tr1 and the second delay time tr2 obtained by the above equations (1) and (2). tr=tr1+tr2 (3) The first piping volume V1 and the second piping volume V2 can be specified in advance as design information of each flow path that constitutes the fuel supply system 2.

[0034] The delay time tr calculated in this manner by the delay time calculation unit 114 is applied to the second flow rate FR2 used to calculate the correction value Tamd in the correction value calculation unit 108. That is, the correction value calculation unit 108 calculates the correction value Tamd based on the result of applying the delay time tr to the second flow rate FR2. The correction value Tamd calculated using the second flow rate FR2 to which the delay time tr has been applied in this manner is approximately equal to the ideal correction value Tamd', as shown in FIG.

[0035] Therefore, in the first embodiment, the target exhaust gas temperature Te0 can be corrected using a correction value Tamd that is approximately equal to the ideal correction value Tamd', so that, as in the reference technology described above with reference to Figure 3, it is possible to preferably prevent the correction value Tamd from deviating from the ideal correction value Tamd' when the second fuel F2 is increased or decreased, thereby preventing an overshoot in the turbine inlet temperature or a decrease in performance of the gas turbine 3 (in other words, the deviation area shown by hatching in Figure 3 does not occur).

[0036] Fig. 6 is a block configuration diagram of a gas turbine control device 100 according to a second embodiment, and Fig. 7 is a diagram showing an example of control of the gas turbine 3 by the gas turbine control device 100 of Fig. 6. Compared to the first embodiment described above, the gas turbine control device 100 in the second embodiment includes a delay time setting unit 116 instead of the delay time calculation unit 114.

[0037] The delay time setting unit 116 is configured to set a delay time tr required for the second fuel F2 that has passed through the second flow meter 18 to reach the gas turbine 3. That is, in the second embodiment, the delay time tr is a value set by the delay time setting unit 116.

[0038] The delay time tr, which is a set value, is set so as to specify the timing at which, when the second flow rate FR2 changes, the correction value Tamd calculated by the correction value calculation unit 108 corresponding to the changed value of the second flow rate FR2 is added to the target exhaust gas temperature Te0. Specifically, in Fig. 7, in a period T1 in which the flow rate FR2' of the second fuel F2 at the inlet of the gas turbine 3 (the second flow rate, a flow rate obtained by applying the delay time tr to FR2) monotonically increases, the delay time tr is set so that the correction value Tamd corresponding to the changed flow rate FR2' of the second fuel F2 is added to the target exhaust gas temperature Te0 at the latest timing ta of the period T1 (i.e., the time at which the change of the flow rate of the second fuel F2 supplied to the gas turbine 3 ends). By setting the delay time tr in this manner, the correction value Tamd becomes smaller than the ideal correction value Tamd' during the period T1 (see the hatched area during the period T1 in Figure 7), and therefore, the occurrence of an overshoot in the turbine inlet temperature due to the correction value Tamd exceeding the ideal correction value Tamd' as in the reference technology can be effectively suppressed.

[0039] As described above, according to each of the above embodiments, by calculating the correction value Tamd taking into account the delay time tr until the second fuel F2 passes through the second flow meter 18 and reaches the gas turbine 3, it is possible to preferably prevent overshooting of the control parameter Pc and deterioration of the performance of the gas turbine even when the characteristics of the fuel supplied to the gas turbine 3 change.

[0040] In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described embodiments may be combined as appropriate.

[0041] The contents described in each of the above embodiments can be understood, for example, as follows.

[0042] (1) A gas turbine control device according to one aspect includes: A gas turbine control device for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from the first fuel is connected to a first fuel flow path through which the first fuel flows, a first flow meter provided in the first fuel flow path for detecting a first flow rate of the fuel; a second flow meter provided in the second fuel flow path for detecting a second flow rate of the second fuel; a gas turbine control unit that calculates a control parameter for controlling the gas turbine by adding a correction value calculated based on a result of applying a delay time to the second flow rate detected by the second flow meter to a basic control value calculated based on the first flow rate; and Equipped with The delay time is a first delay time obtained by dividing a first piping volume from an installation position of the second flow meter to a joining position of the second fuel flow path with the first fuel flow path by the second flow rate; a second delay time obtained by dividing a second piping volume from the joining position to the gas turbine by the first flow rate; Includes.

[0043] According to the above aspect (1), the control parameters of the gas turbine are calculated by adding a correction value calculated based on a result of applying a delay time to the flow rate of the second fuel (second flow rate) to a basic control value calculated based on the total fuel flow rate (first flow rate) supplied to the gas turbine. This delay time is calculated to include a first delay time until the second fuel passes through the second flow meter and joins with the first fuel, and a second delay time until the joined fuel reaches the gas turbine. As a result, the control parameters can be obtained by correcting the basic control value in consideration of the delay time until the second fuel passes through the second flow meter and reaches the gas turbine. By controlling the gas turbine using the control parameters obtained in this manner, it is possible to suitably suppress overshooting of the control parameters and degradation of the performance of the gas turbine, even when the characteristics of the fuel supplied to the gas turbine change.

[0044] (2) A gas turbine control device according to another aspect includes: A gas turbine control device for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from the first fuel is connected to a first fuel flow path through which the first fuel flows, a first flow meter provided in the first fuel flow path for detecting a first flow rate of the fuel; a second flow meter provided in the second fuel flow path for detecting a second flow rate of the second fuel; a gas turbine control unit that calculates a control parameter for controlling the gas turbine by adding a correction value corresponding to a value of the second flow rate after the change to a basic control value calculated based on the first flow rate when the second flow rate changes; and Equipped with The gas turbine control unit adds the correction value to the basic control value during a period of change in the second flow rate to which a preset delay time is applied.

[0045] According to the above aspect (2), the control parameters of the gas turbine are calculated by adding a correction value calculated based on the flow rate of the second fuel (second flow rate) to a basic control value calculated based on the total fuel flow rate (first flow rate) supplied to the gas turbine, at a timing that takes a preset delay time into consideration. As a result, the control parameters can be obtained by correcting the basic control value in consideration of the delay time required for the second fuel to reach the gas turbine after passing through the second flow meter. By controlling the gas turbine using the control parameters obtained in this manner, it is possible to preferably suppress overshooting of the control parameters and degradation of the performance of the gas turbine, even when the characteristics of the fuel supplied to the gas turbine change.

[0046] (3) In another embodiment, in the above embodiment (2), When the second fuel is changed to increase, the gas turbine control unit adds the correction value to the basic control value at the time point when the change in the flow rate of the second fuel supplied to the gas turbine ends.

[0047] According to the above aspect (3), when the second fuel changes to increase, the delay time is set so that the timing for adding the correction value to the basic control value coincides with the end point of the change in the flow rate of the second fuel reaching the gas turbine, thereby making it possible to suitably suppress overshooting of the control parameter when the flow rate of the second fuel changes to increase.

[0048] (4) In another embodiment, in any one of the above (1) to (3), The basic control value is a target exhaust gas temperature corresponding to the turbine inlet temperature of the gas turbine.

[0049] According to the above aspect (4), by correcting the target exhaust gas temperature corresponding to the turbine inlet temperature of the gas turbine by adding a correction value calculated based on the flow rate of the second fuel, it is possible to preferably suppress the occurrence of overshoot in the turbine inlet temperature of the gas turbine and the occurrence of performance degradation in the gas turbine even when the flow rate of the second fuel changes.

[0050] (5) In another embodiment, in any one of the above (1) to (4), the first fuel comprises blast furnace gas; The second fuel comprises at least one of converter gas, finex off-gas, or coke oven gas.

[0051] According to the above aspect (5), the present invention is applicable to a gas turbine that uses a fuel obtained by mixing a first fuel, which is blast furnace gas among by-product gases discharged from a steel plant, with a second fuel containing at least one of converter gas, fines off-gas, and coke oven gas.

[0052] (6) A gas turbine control method according to one aspect includes: 1. A gas turbine control method for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel is connected to a first fuel flow path through which the first fuel flows, the method comprising: a detector disposed in the first fuel flow path and detecting a first flow rate of the fuel; a second flow rate detector provided in the second fuel flow path and detecting a second flow rate of the second fuel; calculating a control parameter for controlling the gas turbine by adding a correction value calculated based on a result of applying a delay time to the second flow rate detected by the second flow meter to a basic control value calculated based on the first flow rate; Equipped with The delay time is a first delay time obtained by dividing a first piping volume from an installation position of the second flow meter to a joining position of the second fuel flow path with the first fuel flow path by the second flow rate; a second delay time obtained by dividing a second piping volume from the joining position to the gas turbine by the first flow rate; Includes.

[0053] According to the above aspect (6), the control parameters of the gas turbine are calculated by adding a correction value calculated based on a result of applying a delay time to the flow rate of the second fuel (second flow rate) to a basic control value calculated based on the total fuel flow rate (first flow rate) supplied to the gas turbine. This delay time is calculated to include a first delay time until the second fuel passes through the second flow meter and merges with the first fuel, and a second delay time until the merged fuel reaches the gas turbine. As a result, the control parameters can be obtained by correcting the basic control value in consideration of the delay time until the second fuel passes through the second flow meter and reaches the gas turbine. By controlling the gas turbine using the control parameters obtained in this manner, it is possible to preferably suppress overshooting of the control parameters and degradation of the performance of the gas turbine, even when the characteristics of the fuel supplied to the gas turbine change.

[0054] (7) A gas turbine control method according to another aspect includes: 1. A gas turbine control method for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel is connected to a first fuel flow path through which the first fuel flows, the method comprising: a detector disposed in the first fuel flow path and detecting a first flow rate of the fuel; a second flow rate detector provided in the second fuel flow path and detecting a second flow rate of the second fuel; calculating a control parameter for controlling the gas turbine by adding a correction value corresponding to a value of the second flow rate after the change to a basic control value calculated based on the first flow rate when the second flow rate changes; Equipped with The correction value is added to the basic control value during a period of change in the second flow rate to which a preset delay time is applied.

[0055] According to the above aspect (7), the control parameters of the gas turbine are calculated by adding a correction value calculated based on the flow rate of the second fuel (second flow rate) to a basic control value calculated based on the total fuel flow rate (first flow rate) supplied to the gas turbine, at a timing that takes a preset delay time into consideration. As a result, the control parameters can be obtained by correcting the basic control value in consideration of the delay time required for the second fuel to reach the gas turbine after passing through the second flow meter. By controlling the gas turbine using the control parameters obtained in this manner, it is possible to suitably suppress overshooting of the control parameters and degradation of the performance of the gas turbine, even when the characteristics of the fuel supplied to the gas turbine change. [Explanation of symbols]

[0056] 1. Gas turbine equipment 2 Fuel supply system 3. Gas turbine 4 Primary fuel source 6 Secondary fuel source 8 First fuel passage 10 Second fuel flow path 12 Merging position 14 Mixing channel 16 1st flow meter 18 2nd flow meter 19 Exhaust gas temperature sensor 100 Gas turbine control device 102 1st flow rate acquisition section 104 2nd flow rate acquisition section 106 Target exhaust gas temperature calculation unit 108 Correction value calculation unit 110 Exhaust gas temperature acquisition unit 112 Control parameter calculation unit 114 Delay time calculation unit 116 Delay time setting section F fuel F1 1st fuel F2 2nd fuel FR1 1st flow rate FR2 2nd flow rate Pc control parameter Tamd correction value Tamd´ Ideal correction value Te exhaust gas temperature Te0 Target exhaust gas temperature Te0´ Corrected target exhaust gas temperature tr delay time tr1 First delay time tr2 Second delay time

Claims

1. 1. A gas turbine control device for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel is connected to a first fuel flow path through which the first fuel flows, a first flow meter provided in the first fuel flow path for detecting a first flow rate of the fuel; a second flow meter provided in the second fuel flow path for detecting a second flow rate of the second fuel; a gas turbine control unit that calculates a control parameter for controlling the gas turbine by adding a correction value calculated based on a result of applying a delay time to the second flow rate detected by the second flow meter to a basic control value calculated based on the first flow rate; and Equipped with The delay time is a first delay time obtained by dividing a first piping volume from an installation position of the second flow meter to a joining position of the second fuel flow path with the first fuel flow path by the second flow rate; a second delay time calculated by dividing a second piping volume from the joining position to the gas turbine by the first flow rate; A gas turbine control device comprising:

2. 1. A gas turbine control device for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel is connected to a first fuel flow path through which the first fuel flows, a first flow meter provided in the first fuel flow path for detecting a first flow rate of the fuel; a second flow meter provided in the second fuel flow path for detecting a second flow rate of the second fuel; a gas turbine control unit that calculates, when the second flow rate changes, a control parameter for controlling the gas turbine by adding a correction value corresponding to a value of the second flow rate after the change to a basic control value calculated based on the first flow rate; and Equipped with the gas turbine control unit adds the correction value to the basic control value during a period of change in the second flow rate to which a preset delay time has been applied.

3. 3. The gas turbine control device according to claim 2, wherein, when the second fuel is changed to increase, the gas turbine control unit adds the correction value to the basic control value at a time point at which a change in the flow rate of the second fuel supplied to the gas turbine has ended.

4. 3. The gas turbine control device according to claim 1, wherein the basic control value is a target exhaust gas temperature corresponding to a turbine inlet temperature of the gas turbine.

5. the first fuel comprises blast furnace gas; The gas turbine control device according to claim 1 or 2, wherein the second fuel includes at least one of converter gas, finex off-gas, and coke oven gas.

6. 1. A gas turbine control method for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel flow path is connected to a first fuel flow path through which the first fuel flows, the method comprising: a detector disposed in the first fuel flow path and detecting a first flow rate of the fuel; a second flow rate detector provided in the second fuel flow path and detecting a second flow rate of the second fuel; calculating a control parameter for controlling the gas turbine by adding a correction value calculated based on a result of applying a delay time to the second flow rate detected by the second flow meter to a basic control value calculated based on the first flow rate; Equipped with The delay time is a first delay time obtained by dividing a first piping volume from an installation position of the second flow meter to a joining position of the second fuel flow path with the first fuel flow path by the second flow rate; a second delay time calculated by dividing a second piping volume from the joining position to the gas turbine by the first flow rate; A gas turbine control method comprising:

7. 1. A gas turbine control method for controlling a gas turbine that can be operated using fuel supplied from a fuel supply system in which a second fuel flow path capable of supplying a second fuel different from a first fuel flow path is connected to a first fuel flow path through which the first fuel flows, the method comprising: a detector disposed in the first fuel flow path and detecting a first flow rate of the fuel; a second flow rate detector provided in the second fuel flow path and detecting a second flow rate of the second fuel; calculating a control parameter for controlling the gas turbine by adding a correction value corresponding to a value of the second flow rate after the change to a basic control value calculated based on the first flow rate when the second flow rate changes; Equipped with the correction value is added to the basic control value during a period of change in the second flow rate to which a preset delay time has been applied.

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