Gas turbine control device, gas turbine control method, and program

Abstract

The present invention provides a gas turbine control device that can shorten the gas turbine startup time regardless of changes in atmospheric temperature. [Solution] The gas turbine control device includes a startup fuel command value output unit that outputs a startup fuel command value, a fuel control unit that calculates a fuel limit value based on the rotational speed and acceleration rate setting value of the gas turbine, and a selection unit that selects the larger of the startup fuel command value and the fuel limit value as the fuel command value. The fuel control unit includes an acceleration rate limit unit that sets the acceleration rate limit value to a first acceleration rate limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value is less than a predetermined value, and switches the acceleration rate limit value to a second acceleration rate limit value that is lower than the first acceleration rate limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value is greater than a predetermined value, and an acceleration rate setting unit that sets the acceleration rate setting value based on the acceleration rate limit value.

Description

Technical Field

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

Background Art

[0002] When starting a gas turbine, after ignition of fuel in the combustor, the rotor is accelerated at a predetermined acceleration rate setting value until the rotor rotational speed reaches a predetermined rotational speed R1 (for example, the rated rotational speed). FIG. 8 is a diagram showing a control example of the rotor rotational speed N [rpm] and the fuel command value CSO [%] by a conventional gas turbine control device. In FIG. 8, N_L shows an example of the measured value of the rotor rotational speed at a low ambient temperature (in winter, etc.), and N_H shows an example of the measured value of the rotor rotational speed at a high ambient temperature (in summer, etc.). CSO_L shows an example of the fuel command value at a low ambient temperature, and CSO_H shows an example of the fuel command value at a high ambient temperature. As shown in FIG. 8, the gas turbine control device always calculates a fuel limit value FLCSO based on the rotor rotational speed N and the acceleration rate setting, and selects the higher value between a warm-up fuel command value WUP CSO, which is a constant value, and the fuel limit value FLCSO as the fuel command value CSO. The gas turbine control device supplies fuel to the combustor based on the fuel command value CSO.

[0003] Referring to the example at low atmospheric temperature shown in Figure 8, we will describe the conventional control method for the fuel command value CSO. Immediately after fuel supply and ignition start (Fuel ON) at time t1, the rotor speed N jumps to a value greater than the target speed based on the acceleration rate setting. Therefore, the gas turbine control device performs feedback control to reduce the difference between the rotor speed N and the target speed, and the fuel limit value FLCSO temporarily decreases. Subsequently, as the jump in rotor speed N settles down, the fuel limit value FLCSO increases. At time t2, when the fuel limit value FLCSO becomes higher than the warm-up fuel command value WUP CSO, the gas turbine control device selects the fuel limit value FLCSO as the fuel command value CSO. The timing when the fuel limit value FLCSO exceeds the warm-up fuel command value WUP CSO is called acceleration entry. Once acceleration begins, the rotor speed N increases according to the set rate of increase, and the fuel limit value FLCSO also increases. At time t4, when the rotational speed N reaches the predetermined rotational speed R1, the startup is complete.

[0004] Patent Document 1 describes a technique for shortening the startup time of a gas turbine by increasing the rate of increase setting after acceleration is initiated. Patent Document 1 also describes a technique for shortening the startup time of a gas turbine by increasing the rate of increase setting value while the rotor speed N before acceleration is being raised from the ignition speed R0 to a predetermined speed, thereby reducing the drop in the fuel limit value FLCSO that accompanies the jump in rotor speed N, suppressing a delay in the timing of acceleration, and shortening the startup time of a gas turbine. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2024-008393 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] At high atmospheric temperatures, the compressor load is smaller compared to at low atmospheric temperatures. Therefore, as shown in the example in Figure 8, the rise in rotor speed N_H after ignition (time t1) at high atmospheric temperatures is larger than the rise in rotor speed N_L at low atmospheric temperatures. Consequently, at high atmospheric temperatures, the difference between rotor speed N1 and the target speed is larger than at low atmospheric temperatures, resulting in a greater drop in the fuel limit value FLCSO_H at high atmospheric temperatures than in low atmospheric temperatures. In this case, if the period for increasing the rate of increase before acceleration is determined based only on rotor speed N, as in conventional technology, at high atmospheric temperatures, the time (time t1 to time t3) until the fuel limit value FLCSO_H, which drops more than at low atmospheric temperatures, exceeds the warm-up fuel command value WUP CSO will be longer. Consequently, at high atmospheric temperatures, the timing of acceleration entry (time t3) will be later than at low atmospheric temperatures (time t2), thus increasing the gas turbine startup time. In the example shown in Figure 8, the startup time is longer at high atmospheric temperatures, from time t5 to time t4.

[0007] The purpose of this disclosure is to provide a gas turbine control device, a gas turbine control method, and a program that can shorten the startup time of a gas turbine regardless of changes in atmospheric temperature. [Means for solving the problem]

[0008] According to one aspect of the present disclosure, a gas turbine control device includes: a startup fuel command value output unit that outputs a startup fuel command value when a gas turbine is started; a fuel control unit that calculates a fuel limit value for the gas turbine based on the rotational speed and acceleration rate setting value of the gas turbine; and a selection unit that selects the larger of the startup fuel command value and the fuel limit value as the fuel command value for the gas turbine. The fuel control unit has an acceleration rate limiting unit that sets the acceleration rate limit value to a first acceleration rate limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value is less than a predetermined value, and switches the acceleration rate limit value to a second acceleration rate limit value that is lower than the first acceleration rate limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value is greater than a predetermined value. The fuel limit value is calculated based on the acceleration rate setting value set by the acceleration rate limit value.

[0009] According to one aspect of the present disclosure, a gas turbine control method includes the steps of: outputting a startup fuel command value when starting a gas turbine; calculating a fuel limit value for the gas turbine based on the rotational speed and acceleration rate setting value of the gas turbine; and selecting the larger of the startup fuel command value and the fuel limit value as the fuel command value for the gas turbine, wherein the step of calculating the fuel limit value includes setting the acceleration rate limit value to a first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is less than a predetermined value, switching the acceleration rate limit value to a second acceleration rate limit value lower than the first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is greater than a predetermined value; and calculating the fuel limit value based on the acceleration rate setting value set by the acceleration rate limit value.

[0010] According to one aspect of the present disclosure, the program causes a gas turbine control device to perform the following steps: output a startup fuel command value when starting up a gas turbine; calculate a fuel limit value for the gas turbine based on the rotational speed and acceleration rate setting value of the gas turbine; and select the larger of the startup fuel command value and the fuel limit value as the fuel command value for the gas turbine, wherein the step of calculating the fuel limit value includes setting the acceleration rate limit value to a first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is less than a predetermined value, switching the acceleration rate limit value to a second acceleration rate limit value that is lower than the first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is greater than a predetermined value; and calculating the fuel limit value based on the acceleration rate setting value set by the acceleration rate limit value. [Effects of the Invention]

[0011] According to the above embodiment, the startup time of the gas turbine can be shortened regardless of changes in atmospheric temperature. [Brief explanation of the drawing]

[0012] [Figure 1] This diagram shows the overall configuration of the gas turbine system according to the first embodiment. [Figure 2] This is a block diagram showing the functional configuration of a gas turbine control device according to the first embodiment. [Figure 3] This is a first block diagram showing the calculation logic of a gas turbine control device according to the first embodiment. [Figure 4] This is a second block diagram showing the calculation logic of a gas turbine control device according to the first embodiment. [Figure 5] This figure shows an example of controlling the rotor speed N [rpm] and fuel command value CSO [%] by a gas turbine control device according to the first embodiment. [Figure 6] This is a block diagram showing the calculation logic of a gas turbine control device according to a modified example of the first embodiment. [Figure 7] It is a schematic block diagram showing the configuration of a computer according to an embodiment. [Figure 8] It is a diagram showing a control example of the rotor rotation speed N [rpm] and the fuel command value CSO [%] by a conventional gas turbine control device.

Mode for Carrying Out the Invention

[0013] <First Embodiment> Hereinafter, embodiments will be described in detail with reference to the drawings.

[0014] (Overall Configuration of Gas Turbine System) FIG. 1 is a diagram showing the overall configuration of a gas turbine system according to the first embodiment. As shown in FIG. 1, the gas turbine system 100 includes a gas turbine 1 and a gas turbine control device 10 that controls the gas turbine 1.

[0015] The gas turbine 1 includes a compressor 2, a combustor 3, and a turbine 4. The compressor 2 and the turbine 4 are connected by a rotor 5. The compressor 2 compresses the air taken in from the outside to generate compressed air. The combustor 3 mixes and burns the compressed air and fuel supplied from the compressor 2 to generate high-temperature combustion gas. The turbine 4 is rotationally driven by the combustion gas generated in the combustor 3. The rotor 5 is provided with a rotation speed measurement unit S1 capable of measuring the rotation speed of the gas turbine 1 (rotor 5). In the following description, the rotation speed of the gas turbine 1 is also referred to as the GT rotation speed N. Also, at the outlet of the compressor 2, there is a pressure measurement unit S2 capable of measuring the discharge pressure P CS of the compressor 2.

[0016] Note that the gas turbine 1 may have a starting motor 6. The starting motor 6 supplies rotational power to the rotor 5 and assists the rotational drive of the gas turbine 1 until the rotational speed of the rotor 5 reaches a rotational speed at which the gas turbine 1 can operate independently during startup of the gas turbine 1.

[0017] (Functional Configuration of Gas Turbine Control Device) Figure 2 is a block diagram showing the functional configuration of a gas turbine control device according to the first embodiment. As shown in Figure 2, the gas turbine control device 10 includes a measurement value acquisition unit 11 and a fuel command value calculation unit 12.

[0018] The measurement value acquisition unit 11 acquires measurement values ​​from sensors provided in various parts of the gas turbine 1. In this embodiment, the measurement value acquisition unit 11 acquires the GT rotational speed N from the rotational speed measurement unit S1 and the discharge pressure P of the compressor 2 from the pressure measurement unit S2. CS Obtain it.

[0019] The fuel command value calculation unit 12 calculates the fuel command value CSO (Control Signal Output) and outputs it to the gas turbine 1. The gas turbine 1 adjusts the opening of the flow control valve 7 so that the amount of fuel supplied to the combustor 3 matches the fuel command value CSO.

[0020] (Calculation logic of the fuel command value calculation unit) Figure 3 is a first block diagram showing the calculation logic of a gas turbine control device according to the first embodiment. As shown in Figure 3, the fuel command value calculation unit 12 includes a startup fuel command value output unit 20, a governor control unit 23, a load limiter control unit 24, a temperature control unit 25, a fuel control unit 26, a low value selection unit 27, a high value selection unit 28 (selection unit), and a fuel command value output unit 29.

[0021] The startup fuel command value output unit 20 outputs a startup fuel command value (startup CSO). The startup fuel command value output unit 20 has an ignition fuel command value output unit 21. In addition, the startup fuel command value output unit 20 may further have a warm-up fuel command value output unit 22, as shown in Figure 3.

[0022] The ignition fuel command value output unit 21 includes an ignition command signal input unit 211, a signal generator 212, and a switch 213. When the gas turbine 1 is started, the ignition command signal input unit 211 receives an ignition command signal (Fuel ON) and turns on the switch 213 to output the ignition fuel command value (ignition CSO) generated by the signal generator 212.

[0023] The warm-up fuel command value output unit 22 includes an ignition detection signal input unit 221, a signal generator 222, and a switch 223. When an ignition detection signal indicating that fuel ignition has been detected is input to the ignition detection signal input unit 221 during the startup of the gas turbine 1, the ignition detection signal input unit 221 turns on the switch 223 and outputs the warm-up fuel command value (WUP CSO; Warm UP Control Signal Output) generated by the signal generator 222.

[0024] The ignition CSO and warm-up fuel command value WUP CSO are examples of start-up fuel command values ​​output by the start-up fuel command value output unit 20. The ignition CSO and warm-up fuel command value WUP CSO are preset fixed values. The warm-up fuel command value WUP CSO is a smaller value than the ignition CSO. Either the ignition CSO or the warm-up fuel command value WUP CSO is output and input to the high value selection unit 28. If the start-up fuel command value output unit 20 has only an ignition fuel command value output unit 21, the start-up fuel command value output unit 20 may output only the ignition CSO as the start-up fuel command value. In this case, the start-up fuel command value output unit 20 continues to output the ignition CSO even after the ignition detection signal is input.

[0025] The governor control unit 23 performs rotational speed control as governor operation after the gas turbine 1 has reached a predetermined rotational speed R1 (e.g., rated rotational speed), and calculates and outputs a control command value GVCSO (Governor Control Signal Output) to bring the GT rotational speed closer to the target rotational speed. The load limiter control unit 24 performs load control as load limiter operation, and calculates and outputs a control command value LDCSO (Load limit Control Signal Output) to bring the actual load closer to the target load. The temperature control unit 25 performs exhaust gas temperature control of the turbine 4 and calculates and outputs a control command value EXCSO (Exhaust Control Signal Output) to keep the exhaust gas temperature within an acceptable range. The temperature control unit 25 also performs blade path temperature control and calculates and outputs a control command value BPCSO (Blade Pass Control Signal Output) to keep the blade path temperature (combustion gas temperature) within an acceptable range. Note that the governor control unit 23, load limiter control unit 24, and temperature control unit 25 may be those of the prior art.

[0026] The fuel control unit 26 calculates a fuel limit value FLCSO (Fuel Limit Control Signal Output) based on the GT rotational speed and the speed increase rate setting value when the gas turbine 1 is started up.

[0027] The low-value selection unit 27 selects and outputs the lowest value from among the control command values ​​GVCSO, LDCSO, EXCSO, BPCSO, and FLCSO calculated by each control unit. The control command value selected by the low-value selection unit 27 is input to the high-value selection unit 28.

[0028] The high-value selection unit 28 selects and outputs the highest value among the input values. Specifically, the high-value selection unit 28 selects and outputs the higher value between the startup fuel command value (either ignition CSO, or ignition CSO and warm-up fuel command value WUP CSO) output by the ignition fuel command value output unit 21 or the startup fuel command value output unit 20, and the lowest value of the control command value selected by the low-value selection unit 27.

[0029] The fuel command value output unit 29 outputs the value selected by the high value selection unit 28 as the fuel command value CSO to the gas turbine 1.

[0030] (Fuel control unit calculation logic) Figure 4 is a second block diagram showing the calculation logic of a gas turbine control device according to the first embodiment. As shown in Figure 4, the fuel control unit 26 includes a fuel limit value calculation unit 31, a rate of increase limit unit 32, a rate of increase setting unit 33, a fuel throttle amount calculation unit 34, and an addition unit 35.

[0031] The fuel limit calculation unit 31 calculates the GT rotational speed N and the discharge pressure P of the compressor 2. CS Based on this, the first fuel limit value FLCSO1 is calculated.

[0032] The acceleration rate limiting unit 32 determines the acceleration rate limiting value for GT rotation speed based on the difference between the fuel limit value FLCSO output by the fuel control unit 26 and the startup fuel command value output by the startup fuel command value output unit 20. Specifically, the acceleration rate limiting unit 32 sets the acceleration rate limiting value to the first acceleration rate limiting value when the fuel limit value FLCSO is lower than the startup fuel command value and the difference between the fuel limit value FLCSO and the startup fuel command value is greater than or equal to a predetermined value. On the other hand, the acceleration rate limiting unit 32 switches the acceleration rate limiting value to a second acceleration rate limiting value, which is lower than the first acceleration rate limiting value, when the difference between the fuel limit value FLCSO and the startup fuel command value approaches a predetermined value.

[0033] The acceleration rate limiting unit 32 includes a subtractor 321, a first determination unit 322, a second determination unit 323, a condition fulfillment determination unit 324, a first signal generator 325, a second signal generator 326, and a switch 327 for performing a process to output a first acceleration rate limit value or a second acceleration rate limit value.

[0034] The subtractor 321 outputs a value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO.

[0035] The first determination unit 322 determines whether the value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO is greater than a predetermined value α (for example, -2[%]). For example, when the startup fuel command value is the warm-up fuel command value WUP CSO, the first determination unit 322 outputs an OFF signal if FLCSO[%]-WUP CSO[%]<α[%], and outputs an ON signal after FLCSO[%]-WUP CSO[%]>α[%].

[0036] The second determination unit 323 determines whether the GT rotational speed N is less than a predetermined rotational speed determination value. The rotational speed determination value may be set to a general upper limit of the rotational speed at which acceleration begins (for example, 1220 rpm). The second determination unit 323 outputs an ON signal if the GT rotational speed N is less than the rotational speed determination value, and outputs an OFF signal if the GT rotational speed N is equal to or greater than the rotational speed determination value.

[0037] The condition fulfillment criterion 324 is an AND circuit and outputs a signal (1) indicating that the condition is met when an ON signal is input from both the first criterion 322 and the second criterion 323, and outputs a signal (0) indicating that the condition is not met when an OFF signal is input from at least one of them.

[0038] The first signal generator 325 and the second signal generator 326 each output different fixed values ​​as acceleration rate limits. The second acceleration rate limit output by the second signal generator 326 is lower than the first acceleration rate limit output by the first signal generator 325. For example, the first signal generator 325 outputs 10%, and the second signal generator 326 outputs 2.7%.

[0039] The switch 327 switches the rate of increase limit value between the signal output by the first signal generator 325 (first rate of increase limit value) and the signal output by the second signal generator 326 (second rate of increase limit value) based on the signal input from the condition fulfillment determination unit 324. When a signal (0) indicating that the condition is not met is input to the switch 327, the first rate of increase limit value of the first signal generator 325 is output as the rate of increase limit value. On the other hand, after a signal (1) indicating that the condition is met is input to the switch 327, the second rate of increase limit value of the second signal generator 326 is output as the rate of increase limit value. The switch 327 also switches to a predetermined rate (for example, 10 6 The first rate-up limit value is (10 min in the example above) at / min. -1 / s) to the second rate-up limit value (2.7min in the above example) -1 Switch to / s gradually.

[0040] In this embodiment, the rate of increase limiting unit 32 monitors the GT rotation speed N with a second determination unit 323 for safety reasons, but in other embodiments, the second determination unit 323 may be omitted. In this case, the condition fulfillment determination unit 324 outputs a signal (1) indicating that the condition is met when an ON signal is input from the first determination unit 322, and outputs a signal (0) indicating that the condition is not met when an OFF signal is input from the first determination unit 322.

[0041] The acceleration rate setting unit 33 sets the acceleration rate setting value based on the acceleration rate limit value. In the example in Figure 4, the acceleration rate limit value is used directly as the acceleration rate setting value. Therefore, in the example in Figure 4, the acceleration rate limiting unit 32 may also perform the function of the acceleration rate setting unit 33. In this case, the fuel control unit 26 calculates the fuel limit value based on the acceleration rate setting value (= acceleration rate limit value) set by the acceleration rate limit value.

[0042] The fuel throttle amount calculation unit 34 calculates the fuel flow throttle amount based on the difference between the GT rotational speed N (measured value) and the target rotational speed of the gas turbine 1 according to the speed increase rate setting value. The fuel throttle amount calculation unit 34 includes a function generator 341, a subtractor 342, and a proportional calculator 343 for calculating the fuel throttle amount.

[0043] The function generator 341 calculates and outputs a target rotational speed obtained by correcting the GT rotational speed N by the acceleration rate setting value. For example, the function generator 341 calculates the target rotational speed by adding the rotational speed increase corresponding to the acceleration rate setting value to the GT rotational speed N. As mentioned above, immediately after ignition, the GT rotational speed N temporarily increases at an acceleration rate exceeding the acceleration rate setting value. Therefore, when the GT rotational speed N increases at an acceleration rate exceeding the acceleration rate setting value in this way, the function generator 341 outputs a target rotational speed that is delayed compared to the actual GT rotational speed N by adding a negative rotational speed increase corresponding to the acceleration rate setting value to the GT rotational speed N.

[0044] The subtractor 342 outputs a value obtained by subtracting the GT rotation speed N (measured value) from the target rotation speed.

[0045] The proportional calculator 343 calculates and outputs the fuel restriction amount by multiplying the difference between the target rotational speed and the GT rotational speed N (measured value) by a predetermined coefficient.

[0046] The addition unit 35 outputs a value obtained by adding the first fuel limit value FLCSO1 calculated by the fuel limit value calculation unit 31 and the fuel restriction amount calculated by the fuel restriction amount calculation unit 34. The value output by the addition unit 35 is used as the fuel limit value FLCSO output by the fuel control unit 26.

[0047] (Example of operation) Figure 5 shows an example of control between rotor speed N [rpm] and fuel command value CSO [%] by a gas turbine control device according to the first embodiment. Here, an example of operation of the gas turbine control device 10 of this embodiment will be described with reference to Figure 5. In Figure 5, N represents an example of an actual measured value of GT rotation speed N under the control of this embodiment. N_L and N_H are examples of actual measured values ​​of GT rotation speed N at low and high atmospheric temperatures under the same conventional control as in Figure 8, as comparative examples. CSO represents an example of a fuel command value CSO under the control of this embodiment. CSO_L and CSO_H are examples of fuel command values ​​CSO at low and high atmospheric temperatures under the same conventional control as in Figure 8.

[0048] Conventional technology monitors only the GT rotational speed N, and when the GT rotational speed N rises to a predetermined speed, the acceleration rate setting is reduced. This means that the acceleration rate setting may be reduced before the fuel limit values ​​FLCSO_L and FLCSO_H have risen sufficiently. As a result, the timing of acceleration initiation, when the fuel limit values ​​FLCSO_L and FLCSO_H exceed the warm-up fuel command value WUP CSO, is delayed.

[0049] On the other hand, as described above, the gas turbine control device 10 according to this embodiment selects the first acceleration rate limit value as the acceleration rate setting value while the fuel limit value FLCSO calculated by the fuel control unit 26 is significantly lower than a predetermined value α from the warm-up fuel command value WUP CSO, and selects a first acceleration rate limit value lower than the first acceleration rate limit value as the acceleration rate setting value after the fuel limit value FLCSO approaches within a predetermined value α from the warm-up fuel command value WUP CSO. In this way, during the warm-up period (the period before acceleration) after the ignition start time t11, the acceleration rate setting value is set to a high value (first acceleration rate limit value) while the fuel limit value FLCSO is significantly lower than the warm-up fuel command value WUP CSO, so that the drop in the fuel limit value FLCSO (the amount of decrease in the fuel limit value FLCSO after the ignition start time t11) that accompanies the jump in GT rotational speed N immediately after ignition can be reduced. By reducing the dip in the fuel limit value FLCSO in this way, the timing of acceleration initiation, when the fuel limit value FLCSO exceeds the warm-up fuel command value WUP CSO, can be advanced. As shown in Figure 5, in this embodiment, acceleration can be initiated at time t12, and the period until acceleration initiation (times t11 to t12) can be shortened compared to the conventional technology (times t11 to t13 at low atmospheric temperatures).

[0050] Furthermore, in this embodiment, the acceleration rate setting value is switched by monitoring the difference between the fuel limit value FLCSO and the warm-up fuel command value WUP CSO, regardless of the GT rotational speed N. Unlike the conventional technology, this makes it possible to suppress the dip in the fuel limit value FLCSO without being affected by the rise in GT rotational speed N due to ambient temperature. Therefore, with the control of this embodiment, the period until acceleration begins (times t11 to t12) at high ambient temperatures can be significantly shortened compared to the conventional technology (times t11 to t14).

[0051] Furthermore, as shown in Figure 5, in this embodiment, because the timing of acceleration initiation (time t12) can be brought forward, the timing of completion of gas turbine 1 startup (time t15) can also be brought forward. As a result, the startup time in this embodiment can be shortened compared to the conventional technology.

[0052] (Effects and Benefits) As described above, the gas turbine control device 10 according to this embodiment includes a warm-up fuel command value output unit 22 that outputs a warm-up fuel command value WUP CSO when the gas turbine 1 is started up, a fuel control unit 26 that calculates a fuel limit value FLCSO for the gas turbine 1 based on the GT rotational speed N and the rate of increase setting value, and a selection unit 28 that selects the larger of the warm-up fuel command value WUP CSO and the fuel limit value FLCSO as the fuel command value CSO for the gas turbine. The fuel control unit 26 includes a rate of increase limit unit 32 that sets the rate of increase limit value to a first rate of increase limit value when the value obtained by subtracting the warm-up fuel command value WUP CSO from the fuel limit value FLCSO is smaller than a predetermined value α, and switches the rate of increase limit value to a second rate of increase limit value that is lower than the first rate of increase limit value when the value obtained by subtracting the warm-up fuel command value WUP CSO from the fuel limit value FLCSO is larger than a predetermined value α, and a rate of increase setting unit 33 that sets a rate of increase setting value based on the rate of increase limit value.

[0053] In this way, the gas turbine control device 10 can reduce the drop in the fuel limit value FLCSO that occurs when the GT rotational speed N jumps immediately after ignition of the gas turbine 1. This allows the timing of acceleration initiation, when the fuel limit value FLCSO exceeds the warm-up fuel command value WUP CSO, to be advanced, thereby shortening the gas turbine 1's startup time. Furthermore, in conventional technology, the rate of increase setting value was determined solely by the GT rotational speed N, which meant that the timing of acceleration initiation could be delayed due to the magnitude of the jump in GT rotational speed at high atmospheric temperatures. In contrast, in this embodiment, the rate of increase limit value is set based on the difference between the fuel limit value FLCSO and the warm-up fuel command value WUP CSO, making it possible to advance the timing of acceleration initiation without being affected by atmospheric temperature. As a result, the gas turbine 1's startup time can be stably shortened regardless of atmospheric temperature.

[0054] Furthermore, the fuel control unit 26 includes a fuel throttle amount calculation unit 34 that calculates the fuel flow throttle amount based on the difference between the measured value of the GT rotational speed N and the target rotational speed corresponding to the speed increase rate setting value.

[0055] In this way, the gas turbine control device 10 can delay the rate of acceleration of the gas turbine 1 so that the GT rotational speed N, which jumped up when the gas turbine 1 was started, approaches the target rotational speed.

[0056] Furthermore, the acceleration rate limiting unit 32 switches to the second acceleration rate limiting value if the measured value of the GT rotational speed N exceeds a predetermined rotational speed determination value, even if the value obtained by subtracting the warm-up fuel command value WUP CSO from the fuel limiting value FLCSO is smaller than a predetermined value α.

[0057] In this way, the gas turbine control device 10 can prevent the fuel limit value FLCSO from becoming abnormally large by mistakenly setting the rate of increase setting value based on a large first rate of increase limit value after the GT rotational speed N has risen sufficiently.

[0058] <Modified form of the first embodiment> Figure 6 is a block diagram showing the calculation logic of a gas turbine control device according to a modified example of the first embodiment. The fuel control unit 26 of the gas turbine control device 10 according to the first embodiment may have some configuration changes as shown in Figure 6. Specifically, as shown in Figure 6, the fuel control unit 26 further includes a second rate-up setting unit 36. In this modified example, the rate-up setting unit 33 has a different configuration from the rate-up limiting unit 32. Other functional configurations are the same as in the first embodiment.

[0059] The second speed-up rate setting unit 36 ​​sets a second speed-up rate setting value based on the GT rotation speed N. For example, if the GT rotation speed N is less than the rotation speed determination value (which may be the same as the rotation speed determination value of the second determination device 323), the second speed-up rate setting unit 36 ​​sets the first setting value as the second speed-up rate setting value. Also, if the GT rotation speed N is equal to or greater than the rotation speed determination value, the second speed-up rate setting unit 36 ​​sets a second setting value that is lower than the first setting value as the second speed-up rate setting value. For example, the first setting value may be the same value as the signal output by the first signal generator 325 of the speed-up rate limiting unit 32 (first speed-up rate limiting value), and the second setting value may be the same value as the signal output by the second signal generator 326 of the speed-up rate limiting unit 32 (second speed-up rate limiting value), or they may be different values.

[0060] Furthermore, the acceleration rate setting unit 33 in this modified example is a low-value selector, which selects the lower of the acceleration rate limit value input from the acceleration rate limiting unit 32 and the second acceleration rate setting value input from the second acceleration rate setting unit 36, and outputs it as the acceleration rate setting value. The value selected by the acceleration rate setting unit 33 (acceleration rate setting value) is input to the fuel throttle amount calculation unit 34 (function generator 341).

[0061] In this way, the gas turbine control device 10 can more reliably prevent the fuel limit value FLCSO from becoming abnormally large, as the rate of increase setting value is incorrectly set based on a large first rate of increase limit value after the GT rotational speed N has risen sufficiently.

[0062] (Computer configuration) Figure 7 is a schematic block diagram showing the configuration of a computer according to one embodiment. The computer 900 comprises a processor 901, main memory 902, auxiliary memory 903, and interface 904. The gas turbine control device 10 described above is implemented in the computer 900. The operation of each processing unit described above is stored in the auxiliary memory 903 in the form of a program. The processor 901 reads the program from the auxiliary memory 903, loads it into the main memory 902, and executes the above processing according to the program. The processor 901 also allocates memory area in the main memory 902 to be used for the above processing according to the program.

[0063] The program may be for implementing a part of the functions to be performed by the computer 900. For example, the program may perform functions in combination with other programs already stored in the auxiliary storage device 903, or in combination with other programs implemented in other devices. In other embodiments, the computer may be equipped with a custom LSI (Large Scale Integrated Circuit) such as a PLD (Programmable Logic Device) in addition to, or in place of, the above configuration. Examples of PLDs include PAL (Programmable Array Logic), GAL (Generic Array Logic), CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array), etc. In this case, some or all of the functions implemented by the processor may be implemented by the integrated circuit.

[0064] Examples of auxiliary storage devices 903 include HDDs (Hard Disk Drives), SSDs (Solid State Drives), magnetic disks, magneto-optical disks, CD-ROMs (Compact Disc Read Only Memory), DVD-ROMs (Digital Versatile Disc Read Only Memory), and semiconductor memory. The auxiliary storage device 903 may be an internal medium directly connected to the bus of the computer 900, or it may be an external medium (external storage device 910) connected to the computer 900 via an interface 904 or a communication line. Furthermore, if this program is distributed to the computer 900 via a communication line, the computer 900 that receives the distribution may expand the program into the main memory 902 and execute the above processing. In at least one embodiment, the auxiliary storage device 903 is a tangible storage medium that is not temporary.

[0065] <Note> The above-described embodiment can be understood, for example, as follows:

[0066] (1) According to the first embodiment, the gas turbine control device 10 includes a startup fuel command value output unit 20 that outputs a startup fuel command value when the gas turbine 1 is started up, a fuel control unit 26 that calculates a fuel limit value FLCSO for the gas turbine 1 based on the rotational speed N and the rate of increase setting value of the gas turbine 1, and a selection unit 28 that selects the larger of the startup fuel command value and the fuel limit value FLCSO as the fuel command value CSO for the gas turbine, wherein the fuel control unit 26 has a rate of increase limit unit 32 that sets the rate of increase limit value to a first rate of increase limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO is less than a predetermined value α, and switches the rate of increase limit value to a second rate of increase limit value which is lower than the first rate of increase limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO is greater than a predetermined value α, and calculates the fuel limit value based on the rate of increase setting value set by the rate of increase limit value.

[0067] In this way, the gas turbine control device 10 can reduce the drop in the fuel limit value FLCSO that occurs when the GT rotational speed N jumps immediately after ignition of the gas turbine 1. As a result, the timing of acceleration initiation, when the fuel limit value FLCSO exceeds the start-up fuel command value (e.g., warm-up fuel command value WUP CSO), can be advanced, thereby shortening the gas turbine 1's startup time. Furthermore, in the conventional technology, the acceleration rate setting value was set depending only on the GT rotational speed N, so the timing of acceleration initiation could be delayed due to the magnitude of the jump in GT rotational speed at high atmospheric temperatures. In contrast, in this embodiment, the acceleration rate limit value is set based on the difference between the fuel limit value FLCSO and the start-up fuel command value, so the timing of acceleration initiation can be advanced without being affected by atmospheric temperature. As a result, the gas turbine 1's startup time can be stably shortened regardless of atmospheric temperature.

[0068] (2) According to the second embodiment, in the gas turbine control device 10 according to the first embodiment, the fuel control unit 26 further includes a fuel throttle amount calculation unit 34 that calculates a fuel flow throttle amount based on the difference between the measured value of the rotational speed N of the gas turbine 1 and the target rotational speed of the gas turbine 1 corresponding to the speed increase rate setting value.

[0069] In this way, the gas turbine control device 10 can delay the rate of acceleration of the gas turbine 1 so that the GT rotational speed N, which jumped up when the gas turbine 1 was started, approaches the target rotational speed.

[0070] (3) According to the third embodiment, in the gas turbine control device 10 according to the first or second embodiment, the fuel control unit 26 further includes a speed rate setting unit 33 for setting a speed rate setting value and a second speed rate setting unit 36 ​​for setting a second speed rate setting value based on a measured value of the rotational speed N of the gas turbine 1, and the speed rate setting unit 33 sets the lower of the speed rate limit value and the second speed rate setting value as the speed rate setting value.

[0071] In this way, the gas turbine control device 10 can more reliably prevent the fuel limit value FLCSO from becoming abnormally large, as the rate of increase setting value is incorrectly set based on a large first rate of increase limit value after the GT rotational speed N has risen sufficiently.

[0072] (4) According to the fourth embodiment, in a gas turbine control device 10 according to any one of the first to third embodiments, the rate of increase limiting unit 32 switches to the second rate of increase limiting value when the measured value of the rotational speed N of the gas turbine 1 exceeds a predetermined rotational speed determination value, even if the value obtained by subtracting the startup fuel command value from the fuel limiting value FLCSO is less than a predetermined value α.

[0073] In this way, the gas turbine control device 10 can prevent the fuel limit value FLCSO from becoming abnormally large by mistakenly setting the rate of increase setting value based on a large first rate of increase limit value after the GT rotational speed N has risen sufficiently.

[0074] (5) According to the fifth embodiment, in the gas turbine control device 10 according to any one of the first to fourth embodiments, the second speed-up rate setting unit 36 ​​sets the second speed-up rate setting value such that the smaller the measured value of the rotational speed N of the gas turbine 1, the higher the value.

[0075] In this way, the gas turbine control device 10 can ensure that the fuel limit value FLCSO rises rapidly during periods when the rotational speed N of the gas turbine 1 is in the low-speed range.

[0076] (6) According to the sixth aspect, the gas turbine control method includes the steps of: outputting a startup fuel command value when the gas turbine 1 is started; calculating a fuel limit value FLCSO for the gas turbine 1 based on the rotational speed N and the rate of increase setting value of the gas turbine 1; and selecting the larger of the startup fuel command value and the fuel limit value FLCSO as the fuel command value CSO for the gas turbine 1, wherein the step of calculating the fuel limit value FLCSO includes setting the rate of increase limit value to a first rate of increase limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO is less than a predetermined value α, switching the rate of increase limit value to a second rate of increase limit value which is lower than the first rate of increase limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO is greater than a predetermined value α; and calculating a fuel limit value based on the rate of increase setting value set by the rate of increase limit value.

[0077] (7) According to the seventh aspect, the program causes the gas turbine control device 10 to execute the following steps: outputting a startup fuel command value when the gas turbine 1 is started; calculating a fuel limit value FLCSO for the gas turbine 1 based on the rotational speed N and the rate of increase setting value of the gas turbine 1; and selecting the larger of the startup fuel command value and the fuel limit value FLCSO as the fuel command value CSO for the gas turbine 1, wherein the step of calculating the fuel limit value FLCSO includes setting the rate of increase limit value to a first rate of increase limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO is less than a predetermined value α, switching the rate of increase limit value to a second rate of increase limit value which is lower than the first rate of increase limit value when the value obtained by subtracting the startup fuel command value from the fuel limit value FLCSO is greater than a predetermined value α; and calculating a fuel limit value based on the rate of increase setting value set by the rate of increase limit value. [Explanation of Symbols]

[0078] 100 Gas Turbine Systems 1 Gas Turbine 2 Compressor 3 Combustor 4 Turbines 5 rotors 6. Starting motor 7 Flow control valve 10 Gas turbine control system 11 Measurement Value Acquisition Unit 12 Fuel command value calculation unit 20 Startup fuel command value output unit 21 Ignition fuel command value output unit 211 Ignition command signal input section 212 Signal Generator 213 switches 22 Warm-up fuel command value output unit 221 Ignition detection signal input section 222 Signal Generator 223 Switch 23 Governor Control Unit 24 Load Limiter Control Unit 25 Temperature control unit 26 Fuel Control Unit 27 Low-value selection section 28 High Price Selection Section 28 Selection Section 29 Fuel command value output unit 31 Fuel Limit Calculation Unit 32 Speed ​​increase rate limiting section 321 Subtractor 322 1st determiner 323 Second determiner 324 Condition establishment determiner 325 First signal generator 326 Second signal generator 327 Switch 33 Speed ​​increase rate setting section 34 Fuel Reduction Amount Calculation Unit 341 Function Generator 342 Subtractors 343 Proportional calculator 35 Addition section 36. Second Speed ​​Increase Setting Section

Claims

1. A startup fuel command value output unit outputs a startup fuel command value when a gas turbine is started up, A fuel control unit that calculates a fuel limit value for the gas turbine based on the rotational speed and acceleration rate setting value of the gas turbine, A selection unit that selects the larger of the above-mentioned startup fuel command value and the above-mentioned fuel limit value as the fuel command value for the gas turbine, Equipped with, The fuel control unit, The acceleration rate limiting unit has a setting that sets the acceleration rate limiting value to a first acceleration rate limiting value when the value obtained by subtracting the startup fuel command value from the fuel limiting value is less than a predetermined value, and switches the acceleration rate limiting value to a second acceleration rate limiting value that is lower than the first acceleration rate limiting value when the value obtained by subtracting the startup fuel command value from the fuel limiting value is greater than a predetermined value. The fuel limit value is calculated based on the acceleration rate setting value set by the acceleration rate limit value. Gas turbine control system.

2. The fuel control unit further includes a fuel throttle amount calculation unit that calculates a fuel flow throttle amount based on the difference between the measured rotational speed of the gas turbine and the target rotational speed of the gas turbine corresponding to the speed increase rate setting value. The gas turbine control device according to claim 1.

3. The fuel control unit further includes a speed-up rate setting unit for setting the speed-up rate setting value and a second speed-up rate setting unit for setting a second speed-up rate setting value based on the measured rotational speed of the gas turbine. The acceleration rate setting unit sets the acceleration rate setting value to the lower of the acceleration rate limit value and the second acceleration rate setting value. The gas turbine control device according to claim 1 or 2.

4. The acceleration rate limiting unit switches to the second acceleration rate limiting value when the measured rotational speed of the gas turbine exceeds a predetermined rotational speed determination value, even if the value obtained by subtracting the startup fuel command value from the fuel limiting value is less than a predetermined value. The gas turbine control device according to claim 1 or 2.

5. The second speed-up rate setting unit sets the second speed-up rate setting value such that it becomes higher the smaller the measured rotational speed of the gas turbine is. The gas turbine control device according to claim 3.

6. A step of outputting the startup fuel command value when starting up a gas turbine, A step of calculating the fuel limit value for the gas turbine based on the rotational speed and acceleration rate setting value of the gas turbine, The steps include selecting the larger of the above-mentioned startup fuel command value and the above-mentioned fuel limit value as the fuel command value for the gas turbine, It has, The step of calculating the aforementioned fuel limit value is: The steps include setting the acceleration rate limit value to a first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is less than a predetermined value, and switching the acceleration rate limit value to a second acceleration rate limit value lower than the first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is greater than a predetermined value, A step of calculating the fuel limit value based on the acceleration rate setting value set by the acceleration rate limit value, Having, Gas turbine control method.

7. A step of outputting the startup fuel command value when starting up a gas turbine, A step of calculating the fuel limit value for the gas turbine based on the rotational speed and acceleration rate setting value of the gas turbine, The steps include selecting the larger of the above-mentioned startup fuel command value and the above-mentioned fuel limit value as the fuel command value for the gas turbine, A program that causes the gas turbine control device to execute, The step of calculating the aforementioned fuel limit value is: The steps include setting the acceleration rate limit value to a first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is less than a predetermined value, and switching the acceleration rate limit value to a second acceleration rate limit value lower than the first acceleration rate limit value if the value obtained by subtracting the startup fuel command value from the fuel limit value is greater than a predetermined value, A step of calculating the fuel limit value based on the acceleration rate setting value set by the acceleration rate limit value, Having, program.

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