JP7743374B2 - Gas turbine control device, gas turbine facility, gas turbine control method, and gas turbine control program - Google Patents

Description

This disclosure relates to a gas turbine control device, gas turbine equipment, a gas turbine control method, and a gas turbine control program.

When a gas turbine starts up, after fuel is ignited in the combustor, the rotor speed is increased until it reaches a predetermined rotational speed (e.g., rated rotational speed).

For example, Patent Document 1 describes that when starting a gas turbine, after fuel is ignited, the rotor rotation speed is increased at a predetermined rotation acceleration (acceleration rate) determined based on a safety index that indicates the relationship between damage to gas turbine components and the rotor rotation acceleration.

Japanese Patent Application Laid-Open No. 2013-221423

In order to shorten the start-up time of a gas turbine, it is conceivable to set the rotor speed increase rate (rotational acceleration) during gas turbine startup to a value greater than conventional. However, if the output of the startup motor, etc. is increased to increase the rotor speed increase rate during the period immediately after ignition of the gas turbine when the fuel supply amount is relatively small, the rotor rotation speed will rise significantly more than conventional, increasing the amount of air suctioned into the compressor. This will reduce the fuel-air ratio (F/A ratio) and increase the possibility of misfire in the combustor.

In view of the above, at least one embodiment of the present invention aims to provide a gas turbine control device, gas turbine equipment, gas turbine control method, and gas turbine control program that are capable of rapidly starting a gas turbine while suppressing misfires.

A control device for a gas turbine according to at least one embodiment of the present invention comprises:
A control device for controlling operation of a gas turbine, comprising:
a fuel command value calculation unit for calculating a fuel command value to be given to the gas turbine;
a speed increase rate setting unit for setting a speed increase rate setting value of a rotor of the gas turbine;
Equipped with
The speed-up rate setting unit is configured to increase the speed-up rate set value after a switching timing at which the fuel command value calculated by the fuel command value calculation unit switches from a constant value to a continuously increasing value, during startup of the gas turbine.

Furthermore, a control device for a gas turbine according to at least one embodiment of the present invention includes:
A control device for controlling operation of a gas turbine, comprising:
a fuel command value calculation unit for calculating a fuel command value to be given to the gas turbine;
a motor output setting unit for setting an output setting value of the startup motor of the gas turbine;
Equipped with
The motor output setting unit is configured to increase the output set value after a switching timing at which the fuel command value calculated by the fuel command value calculation unit switches from a constant value to a continuously increasing value during startup of the gas turbine.

Moreover, the gas turbine equipment according to at least one embodiment of the present invention includes:
a gas turbine including a compressor for compressing air, a combustor for generating combustion gas by a combustion reaction between the compressed air from the compressor and fuel, and a turbine driven by the combustion gas from the combustor;
the controller as described above configured to control operation of the gas turbine;
Equipped with.

Further, a gas turbine control method according to at least one embodiment of the present invention includes:
1. A control method for controlling operation of a gas turbine, comprising:
a fuel command value calculation step of calculating a fuel command value to be given to the gas turbine;
a speed increase rate setting step of setting a speed increase rate set value of a rotor of the gas turbine;
Equipped with
In the speed-up rate setting step, during startup of the gas turbine, the speed-up rate set value is increased after a switching timing at which the fuel command value calculated in the fuel command value calculation step switches from a constant value to a continuously increasing value.

Further, a control program for a gas turbine according to at least one embodiment of the present invention includes:
A control program for controlling operation of a gas turbine, comprising:
On the computer,
a fuel command value calculation step of calculating a fuel command value to be given to the gas turbine;
a speed-up rate setting step of setting a speed-up rate set value for a rotor of the gas turbine;
configured to cause
In the step of setting a speed-up rate, during startup of the gas turbine, the speed-up rate set value is increased after a switching timing at which the fuel command value calculated in the step of calculating a fuel command value switches from a constant value to a continuously increasing value.

At least one embodiment of the present invention provides a gas turbine control device, gas turbine equipment, gas turbine control method, and gas turbine control program that are capable of rapidly starting a gas turbine while suppressing misfires.

1 is a schematic configuration diagram of a gas turbine facility including a control device according to an embodiment. FIG. 2 is a schematic configuration diagram of a control device according to an embodiment. FIG. 2 is a block diagram illustrating the calculation logic of a control device according to one embodiment. 1 is a graph showing an example of the relationship between the rotor rotation speed and the speed increase rate setting value at the start of the gas turbine. 1 is a graph showing an example of the relationship between the rotor rotation speed and the output setting value of the startup motor when starting up the gas turbine. 1 is a graph showing an example of the relationship between the rotor rotation speed and the speed increase rate setting value at the start of the gas turbine. 1 is a graph showing an example of time-dependent changes in the speed-up rate set value, the startup motor output set value, the rotor rotation speed, the fuel command value, the exhaust gas temperature, and the actual speed-up rate of the rotor when the gas turbine is started up.

Several embodiments of the present invention will be described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention and are merely illustrative examples.

(Gas turbine equipment configuration)
1 is a schematic configuration diagram of a gas turbine facility 100 including a control device according to an embodiment. As shown in FIG. 1, the gas turbine facility 100 includes a gas turbine 1 and a control device 40 for controlling the operation of the gas turbine 1.

The gas turbine 1 includes a compressor 2 for compressing air, a combustor 3 for burning fuel (e.g., natural gas) to generate combustion gas, and a turbine 4 configured to be rotationally driven by the combustion gas. The compressor 2 and turbine 4 are connected via a rotating shaft 5.

Fuel (natural gas, etc.) is supplied to the combustor 3, and compressed air is sent to it from the compressor 2. The fuel is burned using this compressed air as an oxidizer, generating combustion gas. The flow rate of fuel supplied to the combustor 3 can be adjusted by the fuel valve 7.

The combustion gas generated in the combustor 3 is guided to the turbine 4, driving it to rotate. After completing its work in the turbine 4, the combustion gas is discharged from the turbine 4 as exhaust gas. A generator (not shown) may be connected to the turbine 4 via a rotating shaft 5, and the generator may be driven by the turbine 4 to generate electricity.

As shown in FIG. 1, the gas turbine 1 may include a start-up motor 6. The start-up motor 6 is capable of applying rotational power to the rotating shaft 5 of the gas turbine 1 to rotate the rotating shaft 5. The start-up motor 6 may be configured to assist in the rotational driving of the gas turbine 1 when the gas turbine 1 is started up until the gas turbine 1 is able to rotate independently using its own combustion energy.

In some embodiments, the generator described above, which is connected to the gas turbine 1 via the rotating shaft 5, may receive power and function as the start-up motor 6. In this case, to rotate the generator as an electric motor, variable voltage, variable frequency power may be supplied to the generator by a frequency converter such as a static frequency converter (SFC).

The gas turbine 1 may include a rotation speed measurement unit 8 for measuring the rotation speed of the rotating shaft 5 of the gas turbine 1 (rotor rotation speed of the gas turbine 1). The rotation speed measurement unit 8 may include a rotation speed sensor such as an encoder. A signal indicating the rotor rotation speed measured by the rotation speed measurement unit 8 is sent to the control device 40.

(Configuration of control device)
FIG. 2 is a schematic diagram of a control device 40 according to one embodiment. As shown in FIG. 2, the control device 40 includes a fuel command value calculation unit 42 and a speed increase rate setting unit 44. The control device 40 may also include a motor output setting unit 46 and/or a memory unit 48. The control device 40 is configured to receive a signal indicating the measured value (actual rotation speed) of the rotor rotation speed from the rotation speed measurement unit 8 and process the signal. The calculation result of the control device 40 may be sent to the fuel valve 7 or the start-up motor 6, and the fuel valve 7 or the start-up motor 6 may operate based on the calculation result.

The fuel command value calculation unit 42 is configured to calculate a fuel command value FI to be given to the gas turbine 1. The opening of the fuel valve 7 is adjusted based on this fuel command value FI. The control device 40 may be configured to adjust the opening of the fuel valve 7 so that it matches the fuel command value FI.

The speed-up rate setting unit 44 is configured to set a speed-up rate setting value for the rotor during startup of the gas turbine 1. The speed-up rate setting unit 44 may be configured to set different speed-up rate setting values depending on the rotational speed (rated rotational speed, etc.) during operation of the gas turbine 1 after startup. The speed-up rate setting value may be used by the fuel command value calculation unit 42 to calculate the fuel command value FI.

The motor output setting unit 46 is configured to set the output setting value of the startup motor 6 during startup of the gas turbine 1. The output setting value set by the motor output setting unit 46 is sent to the startup motor 6, and the startup motor 6 operates to obtain the set output. Note that when a generator is used as the startup motor 6 together with a frequency conversion device such as an SFC, the motor output setting unit 46 may be configured to set the output setting value of the frequency conversion device as the output setting value of the startup motor 6.

The memory unit 48 is configured to store inputs and outputs to the control device 40, calculation results in the control device 40, etc. The acceleration rate setting unit 44 may be configured to read and set an acceleration rate setting value stored in the memory unit 48. The motor output setting unit 46 may be configured to read and set an output setting value stored in the memory unit 48. The memory unit 48 may include a main memory or auxiliary memory device of the computer that constitutes the control device 40.

The control device 40 includes a computer equipped with a processor (e.g., CPU), main memory (memory device; e.g., RAM), auxiliary memory, and interface. The control device 40 receives signals from the rotation speed measurement unit 8 via the interface. The processor is configured to process the signals received in this manner. The processor is also configured to process programs loaded into the main memory. This realizes the functions of the above-mentioned functional units (fuel command value calculation unit 42, acceleration rate setting unit 44, and motor output setting unit 46).

The processing performed by the control device 40 is implemented as a program executed by the processor. The program may be stored, for example, in an auxiliary storage device. When the program is executed, it is loaded into the main storage device. The processor reads the program from the main storage device and executes the instructions contained in the program.

Figure 3 is a block diagram showing the calculation logic of the fuel command value calculation unit 42 of the control device 40 according to one embodiment. The fuel command value calculation unit 42 calculates and outputs the fuel command value FI to be given to the gas turbine 1.

In Figure 3, reference numeral 11 denotes a surge prevention control output limiter, 12 denotes a gas turbine rotation speed signal, 14 denotes a subtractor, 16 denotes a function generator, 19 denotes a proportional calculator, 20 denotes a low value selector, 21 denotes a signal generator, 22 denotes an adder, 23 denotes a low value selector, 24 denotes a gas turbine rotation speed control calculation output, 25 denotes a generator output control calculation output, 26 denotes a gas turbine exhaust gas temperature control calculation output, 27 and 28 denote signal generators, 29 denotes a gas turbine fuel ignition command signal, 30 denotes a gas turbine misfire prevention command signal, 31 and 32 denote contacts that close when signals 29 and 30 are on, 33 denotes a high value selector, and 34 denotes a gas turbine control calculation output (fuel command value output).

In the sections denoted by reference numerals 11 to 22, the fuel flow rate (second command value F2) is calculated and output based on the rotational speed of the rotor of the gas turbine 1, etc., as described below. The gas turbine rotational speed control calculation output 24 outputs the fuel flow rate when the gas turbine is operating at or near the rated rotational speed. The generator output control calculation output 25 outputs the fuel flow rate when the generator of the gas turbine 1 is connected to the power grid and transmitting power to it. The gas turbine exhaust gas temperature control calculation output 26 outputs the fuel flow rate determined based on the exhaust gas temperature of the gas turbine so that the turbine blades, etc. of the gas turbine do not become abnormally hot. The low value selector 23 selects the lowest value of these outputs and outputs it to the high value selector 33.

When the gas turbine 1 starts up, the fuel flow rate (second command value F2) from the portions denoted by reference numerals 11 to 22 among the above outputs is the lowest value, and is therefore selected by the low-value selector 23 and output to the high-value selector 33.

On the other hand, when the gas turbine 1 is starting up, the output of the signal generator 27 when the gas turbine fuel ignition command signal 29 is on, or the output of the signal generator 28 when the gas turbine misfire prevention command signal 30 is on, is input to the high-value selector 33. The output of the signal generator 27 or the signal generator 28 (first command value F1) is a constant value.

The maximum value selector 33 selects and outputs the maximum value from multiple inputs. When the gas turbine 1 starts up, the larger of the output of the signal generator 27 (first command value F1) and the fuel flow rate from the portion indicated by reference numerals 11 to 22 (second command value F2) is selected and output to the gas turbine control calculation output 34. In other words, when the gas turbine 1 starts up, the larger of the output of the signal generator 27 (first command value F1) and the fuel flow rate from the portion indicated by reference numerals 11 to 22 (second command value F2) is calculated as the fuel command value FI.

The calculations indicated by reference numerals 11 to 22 will now be explained. The output of the surge prevention control output limiter 11 is calculated from the rotation speed (rotor rotation speed) of the gas turbine 1 and the compressor discharge pressure. The gas turbine rotation speed signal 12 is a signal received from the rotation speed measurement unit 8 (a signal indicating the actual rotation speed of the rotor of the gas turbine 1) and is input to the subtractor 14 and function generator 16.

The function generator 16 receives the actual rotor rotation speed from the gas turbine rotation speed signal 12 and the speed-up rate setting value from the speed-up rate setting unit 44 (see Figure 2), and calculates the target rotation speed of the rotor of the gas turbine 1 based on the actual rotor rotation speed and the speed-up rate setting value. The function generator 16 may also calculate the target rotation speed by adding an increase in rotation speed corresponding to the speed-up rate to the actual rotor rotation speed.

Subtractor 14 subtracts gas turbine rotation speed signal 12 from the output of function generator 16 and inputs the result to proportional calculator 19. Proportional calculator 19 multiplies this by an internally set coefficient and outputs the result. Low value selector 20 outputs the lower of the output of proportional calculator 19 and the output of signal generator 21. Since the output of signal generator 21 is normally zero, the output of low value selector 20 is always a negative value. Adder 22 outputs the sum of the output of surge prevention control output limiter 11 and the output of low value selector 20. In this way, in parts 11 to 22, an output related to fuel flow rate (second command value) is calculated based on the rotation speed of gas turbine 1, etc.

(Gas turbine control flow)
Next, a control method for the gas turbine 1 according to some embodiments will be described. Note that, although the following describes a case where the above-described control device 40 is used to control the above-described gas turbine 1, in some embodiments, the control method for the gas turbine may be executed using another device, or some or all of the procedures described below may be performed manually.

Figures 4 and 6 are graphs showing an example of the relationship between the rotor rotational speed and the speed-up rate setting value at gas turbine startup. Figure 5 is a graph showing an example of the relationship between the rotor rotational speed and the startup motor output setting value at gas turbine startup. Figure 7 is a graph showing an example of the time changes in the speed-up rate setting value, startup motor output setting value, rotor rotational speed (actual rotational speed), fuel command value, exhaust gas temperature, and rotor actual speed-up rate at gas turbine startup for multiple cases (Cases A to D).

In Figures 4 to 7, R0 is the rotor rotation speed at the time of ignition of the gas turbine 1 (time t0 in Figure 7), and R_rated is the rotation speed during operation of the gas turbine 1 after startup (e.g., rated rotation speed). Note that startup of the gas turbine 1 includes the period from when the rotor of the gas turbine 1 begins to rotate until the rotor rotation speed increases to a predetermined rotation speed (e.g., rated rotation speed).

First, the control flow for Case C, a typical example of the prior art, will be explained with reference to Figure 7.

In Case C, during the period before time t0, the rotor of the gas turbine 1 is driven to rotate by the startup motor 6. At this time, the output setting value of the startup motor 6 is set to M0.

At time t0, fuel is ignited in the combustor 3. The rotor rotation speed at this time is R0. At time t0, the speed increase rate setting value and the output setting value of the startup motor 6 are set to predetermined values (for example, values determined in advance depending on the rotation speed after startup of the gas turbine 1). In case C, the speed increase rate setting value is set to A1, and the output setting value of the startup motor 6 is set to M1.

From time t0 onwards, the fuel command value FI calculated by the fuel command value calculation unit 42 remains constant. That is, the fuel command value calculation unit 42 calculates the first command value F1, which is the larger of the first command value F1 (constant value) described above and the second command value F2 calculated from the rotor rotation speed, etc., as the fuel command value FI. Fuel is supplied to the gas turbine 1 based on this fuel command value FI, and the rotor rotation speed increases to a certain extent, as shown in the graph.

At time t6, the fuel command value switches from a constant value to a continuously increasing value. That is, the fuel command value FI calculated by the fuel command value calculation unit 42 switches from the first command value F1, which is a constant value, to the second command value F2, which is calculated based on the rotor rotation speed, etc. The point in time when the fuel command value switches from a constant value to a continuously increasing value is called the switching timing.

After time t6, the speed increase rate setting value is maintained at A1, and the output setting value of the startup motor 6 is maintained at M1. After time t6, the rotor rotation speed increases at a substantially constant slope. This slope corresponds to the speed increase rate setting value A1. The rotor rotation speed is then increased until it reaches a predetermined rotation speed (e.g., the rated rotation speed).

Next, the control flow for Case A according to one embodiment will be described. The control flow in Case A is the same as Case C up until the switching timing (time t6 in Cases A and C) when the fuel command value switches from a constant value to a continuously increasing value. However, in Case A, after the switching timing, the speed increase rate setting unit 44 increases the speed increase rate setting value from A1 (first speed increase rate) to A2 (second speed increase rate). In the example shown in the graph in Figure 7, between time t6 (the switching timing) and time t7, the speed increase rate setting value is increased from A1 to A2, and after time t7, the speed increase rate setting value is maintained at A2.

The speed-up rate setting unit 44 may determine the speed-up rate setting value based on the rotor rotation speed. That is, as shown in Fig. 4, the speed-up rate setting value may be set to _A1 until the rotor rotation speed reaches _RA1 , and then the speed-up rate setting value may be increased from _A1 to _A2 once the rotor rotation speed reaches RA1. Here, _RA1 is a rotation speed equal to or greater than the rotation speed at which the switching occurs. In the example shown in Fig. 4, the speed-up rate setting value is increased from A1 to A2 while the rotor rotation speed changes from RA1 to RA2.

In the above-described Case A, the speed increase rate setting value set after the switching timing is A2, which is greater than A1 in Case C. Therefore, in Case A, the slope of the increase in rotor rotation speed after the switching timing is greater than in Case C. This reduces the time required for the rotor rotation speed to increase to the specified rotation speed, and shortens the startup time of the gas turbine 1.

In addition, to shorten the startup time of the gas turbine 1, it is also possible to set the speed increase rate setting to a relatively large value (A2) from the time of ignition (time t0), as shown in Case D. However, if the speed increase rate setting were set to a uniformly large value (A2) as in Case D, the rotor rotation speed would increase sharply, increasing the amount of air suction in the compressor 2 and reducing the fuel-air ratio (F/A ratio), increasing the likelihood of misfire in the combustor 3. In the graph of Figure 7, the increase in exhaust gas temperature in Case D remains low after ignition at time t0, indicating that this is due to the large increase in rotation speed, which reduces the fuel-air ratio (F/A ratio).

In contrast, in the above-mentioned Case A, the acceleration rate setting value is set to a relatively low value (A1) before the switching timing, and is increased after the switching timing when the fuel command value begins to increase continuously, thereby suppressing a decrease in the fuel-air ratio (F/A ratio) and preventing misfires.

Therefore, in the above-mentioned Case A, the gas turbine can be started rapidly while suppressing misfires.

Furthermore, in compressor 2, if the rotor rotation speed is maintained within a specified rotation speed range, rotating stall may occur, resulting in damage to the blades. In this regard, in the above-mentioned Case A, the speed increase rate setting value is set relatively large after the timing at which the fuel command value switches from constant to continuously increasing, allowing compressor 2 to quickly pass through the rotation speed range where rotating stall occurs. Therefore, the gas turbine can be started up quickly while suppressing rotating stall in the compressor.

In some embodiments, for example, as in the above-described case A, the first speed-up rate A1 is set as the speed-up rate setting value before the switching timing, and the speed-up rate setting value is increased to the second speed-up rate A2 after the switching timing. In some embodiments, the ratio _rA of the second speed-up rate A2 to the first speed-up rate ( _rA = A2/A1) may be 1.2 or greater, or 1.5 or greater.

In this way, by increasing the rotor speed increase rate setting value from the value before the switching timing (first speed increase rate A1) to the second speed increase rate A2, the gas turbine 1 can be started up in a relatively short time while more effectively suppressing misfires due to a decrease in the fuel-air ratio.

In Case A in Figure 7, after the switching timing, the motor output setting unit 46 increases the output setting value of the startup motor 6 from M1 (first output) to M2 (second output). In the example shown in the graph in Figure 7, the output setting value is increased from M1 to M2 between time t6 (the time of the switching timing) and time t7, and the output setting value is maintained at M2 after time t7.

The motor output setting unit 46 may determine the output set value based on the rotor rotation speed. That is, as shown in FIG. 5, the output set value may be set to M1 until the rotor rotation speed reaches R _M1 , and once the rotor rotation speed reaches R _M1 , the output set value may be increased from M1 to M2. Here, R _M1 is a rotation speed equal to or greater than the rotation speed at which the switching timing occurs. In the example shown in FIG. 5, the output set value is increased from M1 to M2 while the rotor rotation speed changes from R _M1 to R _M2 .

In the above-described Case A, during startup of the gas turbine 1, the output setting value of the startup motor 6 is increased after the switching timing at which the fuel command value switches from a constant value to a continuously increasing value. In this way, by increasing the startup motor output setting value along with the speed increase rate setting value after the switching timing, the rotor speed can be increased while suppressing the increase in the fuel command value. This suppresses the increase in temperature of the combustion gas introduced from the combustor 3 to the turbine 4 (i.e., the increase in exhaust gas temperature shown in Figure 7 is also suppressed). Therefore, the gas turbine 1 can be rapidly started while suppressing damage to turbine components caused by high-temperature combustion gas and preventing misfires.

In some embodiments, for example, as in the above-described case A, the first output M1 is set as the output set value of the starter motor 6 before the switching timing, and the output set value is increased to the second output M2 after the switching timing. In some embodiments, the ratio _rB of the second output M2 to the first output M1 ( _rB = M2/M1) may be 1.2 or more or 1.5 or more.

In this way, by increasing the output setting value of the startup motor 6 from the value before the switching timing (first output M1) to the second output M2 after the switching timing, it is possible to effectively suppress the temperature rise of the combustion gas introduced from the combustor 3 to the turbine 4. Therefore, it is possible to rapidly start the gas turbine 1 while effectively suppressing damage to turbine components caused by high-temperature combustion gas and preventing misfires.

In some embodiments, the ratio r _A /r _B of the ratio r _A of the second acceleration rate A2 to the first acceleration rate A1 and the ratio r _B of the second output M2 to the first output M1 is 0.8 or more and 1.2 or less.

In the above-described embodiment, during startup of the gas turbine 1, after the timing at which the fuel command value switches from a constant value to a continuous increase, the acceleration rate setting value and the startup motor output setting value are increased by the same amount. This allows the gas turbine 1 to be rapidly started while effectively suppressing misfires due to a decrease in the fuel-air ratio and damage to turbine components due to an increase in the temperature of the combustion gas.

In some embodiments, the acceleration rate setting unit 44 and the motor output setting unit 46 are configured to simultaneously increase the acceleration rate setting value and the output setting value after the switching timing. For example, in case A in Figure 7, the acceleration rate setting value and the output setting value are simultaneously increased between times t6 and t7.

In the above-described embodiment, during startup of the gas turbine 1, the acceleration rate setting value and the startup motor output setting value are simultaneously increased after the timing at which the fuel command value switches from a constant value to a continuous increase. This allows the gas turbine 1 to be rapidly started while effectively suppressing misfires due to a decrease in the fuel-air ratio and damage to turbine components due to an increase in the temperature of the combustion gas.

In some embodiments, the acceleration rate setting unit 44 is configured to start increasing the acceleration rate setting value from the time of the switch timing until the rotor rotation speed increases by 300 rpm. Note that in Case A in Figure 7, the increase in the acceleration rate setting value starts simultaneously with the switch timing (time t6).

In the above-described embodiment, during startup of the gas turbine 1, after the timing at which the fuel command value switches from constant to continuously increasing, the increase in the speed increase rate set value begins within a short period of time from the timing at which the fuel command value switches from constant to continuously increasing until the rotor rotation speed increases by 300 rpm. This allows the gas turbine to start up more quickly while suppressing misfires.

In some embodiments, the motor output setting unit 46 is configured to start increasing the output setting value of the startup motor 6 from the time of the switch timing until the rotor rotation speed increases by 300 rpm. Note that in case A in Figure 7, the increase in the output setting value starts simultaneously with the switch timing (time t6).

In the above-described embodiment, during startup of the gas turbine 1, after the timing at which the fuel command value switches from constant to continuously increasing, the output setting value of the startup motor 6 begins to increase within a short period of time from the timing at which the fuel command value switches from constant to continuously increasing until the rotor rotation speed increases by 300 rpm. This allows the gas turbine to start up more quickly while suppressing damage to turbine components due to an increase in the temperature of the combustion gas.

Next, the control flow for Case B according to one embodiment will be described. The control flow for Case B is the same as for Case A in that the acceleration rate setting value increases from A1 (first acceleration rate) to A2 (second acceleration rate) after the switching timing (time t6 in Case A, time t3 in Case B) at which the fuel command value switches from a constant value to a continuously increasing value.

In Case B, during startup of the gas turbine 1, a first speed-up rate A1 is set as the speed-up rate set value prior to the switching timing (time t3), and a third speed-up rate A3, which is greater than the first speed-up rate A1, is set as the speed-up rate set value prior to that. In the example shown in the graph in Figure 7, after the ignition of the gas turbine 1 (time t0), the speed-up rate set value is maintained at A3 until time t1, and then the speed-up rate set value is reduced from A3 to A1 between times t1 and t2. Thereafter, between times t4 and t5, after the switching timing (time t3), the speed-up rate set value increases from A1 to A2.

The speed-up rate setting unit 44 may determine the speed-up rate setting value based on the rotor rotation speed. That is, as shown in FIG. 6 , the speed-up rate setting value may be set to A3 until the rotor rotation speed increases from R0 to _RA3 , and then the speed-up rate setting value may be decreased from _A3 to A1 once the rotor rotation speed reaches RA3. In the example shown in FIG. 6 , the speed-up rate setting value is decreased from _A3 to A1 while the rotor rotation speed increases from RA3 to _RA4 . Alternatively, the speed-up rate setting value may be maintained at _A1 until the rotor rotation speed increases from _RA4 to _RA1 , and then the speed-up rate setting value may be increased from A1 to A2 once the rotor rotation speed reaches RA1. In the example shown in FIG. 6 , the speed-up rate setting value is increased from _A1 to _A2 while the rotor rotation speed increases from RA1 to RA2.

In Case B, during startup of the gas turbine 1, at a second time point (t0 to t1) prior to a first time point (times t2 to t3) at which a relatively low first speed-up rate A1 is set as the speed-up rate set value before the switching timing (time t3), a third speed-up rate A3 greater than the first speed-up rate A1 is set as the speed-up rate set value. Therefore, compared to Case A, etc., where the third speed-up rate A3 is not set, the second command value F2 based on the deviation between the actual rotor rotation speed and the target rotation speed becomes larger. This makes it possible to advance the switching timing at which the second command value F2 becomes greater than the first command value F1, thereby enabling more rapid startup of the gas turbine.

The third speed-up rate A3 may be greater than the second speed-up rate A2 set after the switching timing. This increases the second command value F2, which is based on the deviation between the actual rotor rotation speed and the target rotation speed, and further accelerates the switching timing at which the second command value F2 becomes greater than the first command value F1. This enables even more rapid startup of the gas turbine.

The contents described in each of the above embodiments can be understood, for example, as follows:

(1) A control device (40) for a gas turbine according to at least one embodiment of the present invention includes:
A control device for controlling operation of a gas turbine (1), comprising:
a fuel command value calculation unit (42) for calculating a fuel command value to be given to the gas turbine;
a speed increase rate setting unit (44) for setting a speed increase rate setting value of the rotor of the gas turbine;
Equipped with
The speed-up rate setting unit is configured to increase the speed-up rate set value after a switching timing at which the fuel command value calculated by the fuel command value calculation unit switches from a constant value to a continuously increasing value, during startup of the gas turbine.

According to the configuration (1) above, during startup of the gas turbine, the rotor speed increase rate setting value is increased after the switching timing at which the fuel command value switches from a constant value to a continuous increase. In this way, the speed increase rate setting value is set to a relatively low value before the switching timing, and is increased after the switching timing at which the fuel command value begins to continuously increase. This allows the gas turbine to start up in a relatively short time while suppressing a decrease in the fuel-air ratio (F/A ratio) and preventing misfires. In other words, the gas turbine can be started up quickly while preventing misfires.

(2) In some embodiments, in the configuration of (1),
The speed-up rate setting unit is configured to set a first speed-up rate (A1) as the speed-up rate setting value before the switching timing, and to increase the speed-up rate setting value to a second speed-up rate (A2) greater than the first speed-up rate after the switching timing.

According to the configuration (2) above, after the switching timing, the rotor speed increase rate setting value is increased from the value before the switching timing (first speed increase rate) to the second speed increase rate, which makes it possible to start the gas turbine in a relatively short time while more effectively suppressing misfires caused by a decrease in the fuel-air ratio.

(3) In some embodiments, in the configuration of (1) or (2),
The control device for the gas turbine includes:
a motor output setting unit (46) for setting an output setting value of a startup motor of the gas turbine;
The motor output setting unit is configured to increase the output setting value after the switching timing.

According to the configuration (3) above, during startup of the gas turbine, the output setting value of the startup motor is increased after the switching timing at which the fuel command value switches from a constant value to a continuously increasing value. In this way, by increasing the startup motor output setting value along with the speed increase rate setting value after the switching timing, the rotor can be increased while suppressing increases in the fuel command value. This makes it possible to suppress increases in the temperature of the combustion gas introduced from the combustor to the turbine. Therefore, the gas turbine can be rapidly started while suppressing damage to turbine components caused by high-temperature combustion gas and preventing misfires.

(4) In some embodiments, in the configuration of (3),
The motor output setting unit is configured to set a first output (M1) as the output setting value before the switching timing, and to increase the output setting value to a second output (M2) greater than the first output after the switching timing.

According to the configuration (4) above, after the switching timing, the output setting value of the startup motor is increased from the value before the switching timing (first output) to the second output, thereby effectively suppressing the temperature rise of the combustion gas introduced from the combustor to the turbine. Therefore, the gas turbine can be rapidly started while effectively suppressing damage to turbine components caused by high-temperature combustion gas and preventing misfires.

(5) In some embodiments, in the configuration of (3) or (4),
the speed-up rate setting unit is configured to set a first speed-up rate as the speed-up rate set value before the switching timing, and to increase the speed-up rate set value to a second speed-up rate greater than the first speed-up rate after the switching timing;
the motor output setting unit is configured to set a first output as the output set value before the switching timing, and to increase the output set value to a second output greater than the first output after the switching timing;
A ratio _rA / _rB of a ratio _rA of the second speed increase rate to the first speed increase rate and a ratio _rB of the second output to the first output is equal to or greater than 0.8 and equal to or less than 1.2.

According to the configuration (5) above, during gas turbine startup, after the timing at which the fuel command value switches from constant to continuously increasing, the acceleration rate setting value and the startup motor output setting value are increased by the same amount. This allows the gas turbine to start up quickly while effectively suppressing misfires due to a drop in the fuel-air ratio and damage to turbine components due to an increase in combustion gas temperature.

(6) In some embodiments, in any of the configurations (3) to (5) above,
The speed increase rate setting unit and the motor output setting unit are configured to simultaneously increase the speed increase rate setting value and the output setting value after the switching timing.

According to the configuration (6) above, during gas turbine startup, the acceleration rate setting value and the startup motor output setting value are increased simultaneously after the timing at which the fuel command value switches from a constant value to a continuous increase. This allows the gas turbine to start up quickly while effectively suppressing misfires due to a drop in the fuel-air ratio and damage to turbine components due to an increase in combustion gas temperature.

(7) In some embodiments, in any of the configurations (1) to (6) above,
The speed increase rate setting unit is configured to start increasing the speed increase rate set value from the time of the switching timing until the rotation speed of the rotor increases by 300 rpm.

According to the configuration (7) above, during startup of the gas turbine, after the timing at which the fuel command value switches from constant to continuously increasing, the increase in the speed increase rate setting value begins within a short period of time from the timing at which the fuel command value switches from constant to continuously increasing until the rotor rotation speed increases by 300 rpm. This allows the gas turbine to start up more quickly while suppressing misfires.

(8) In some embodiments, in any of the configurations (1) to (7) above,
the fuel command value calculation unit is configured to calculate, during startup of the gas turbine, a larger one of a first command value that is a constant value and a second command value that is calculated based on a deviation between an actual rotation speed of the rotor and a target rotation speed of the rotor, as the fuel command value,
The switching timing is a timing at which the fuel command value calculated by the fuel command value calculation unit switches from the first command value to the second command value.

According to the configuration (8) above, during startup of the gas turbine, the rotor speed increase rate set value is increased after the timing at which the fuel command value switches from the first command value, which is a constant value, to the second command value, which is based on the deviation between the actual rotor rotation speed and the target rotor rotation speed. In this way, the speed increase rate set value is set to a relatively low value before the timing of switching, and is increased after the timing at which the fuel command value begins to increase continuously. This allows the gas turbine to start up in a relatively short time while suppressing a decrease in the fuel-air ratio (F/A ratio) and preventing misfires. In other words, the gas turbine can be started up quickly while preventing misfires.

(9) In some embodiments, in the configuration of (8),
The fuel command value calculation unit is configured to calculate the target rotation speed of the rotor based on the actual rotation speed of the rotor and the speed increase rate set value.

According to the configuration (9) above, the target rotation speed of the rotor is calculated based on the actual rotation speed of the rotor and the speed-up rate setting value, so the second command value of the fuel command value corresponds to the speed-up rate setting value of the rotor. Therefore, the second command value can be appropriately calculated according to the speed-up rate setting value.

(10) In some embodiments, in the configuration of (8) or (9),
The speed-up rate setting unit is configured to set a first speed-up rate (A1) as the speed-up rate setting value at a first time point before the switching timing during startup of the gas turbine, and to set a third speed-up rate (A3) greater than the first speed-up rate as the speed-up rate setting value at a second time point before the first time point.

According to the configuration (10) above, during startup of the gas turbine, at a second point in time prior to the first point in time at which a relatively low first speed-up rate is set as the speed-up rate set value before the switching timing, a third speed-up rate greater than the first speed-up rate is set as the speed-up rate set value. This makes it possible to advance the switching timing at which the second command value, based on the deviation between the actual rotor rotation speed and the target rotor rotation speed, becomes greater than the first command value, thereby enabling more rapid startup of the gas turbine.

(11) A control device (40) for a gas turbine according to at least one embodiment of the present invention includes:
A control device for controlling operation of a gas turbine, comprising:
a fuel command value calculation unit (42) for calculating a fuel command value to be given to the gas turbine;
a motor output setting unit (46) for setting an output setting value of a startup motor for the gas turbine;
Equipped with
The motor output setting unit is configured to increase the output set value after a switching timing at which the fuel command value calculated by the fuel command value calculation unit switches from a constant value to a continuously increasing value during startup of the gas turbine.

According to the configuration (11) above, during startup of the gas turbine, the output setting value of the startup motor is increased after the switching timing at which the fuel command value switches from a constant value to a continuous increase. In this way, by increasing the output setting value of the startup motor after the switching timing, the rotor speed can be increased while suppressing the increase in the fuel command value. This makes it possible to suppress the temperature rise of the combustion gas introduced from the combustor to the turbine. Therefore, damage to turbine components caused by high-temperature combustion gas can be suppressed.

(12) A gas turbine facility (100) according to at least one embodiment of the present invention includes:
a gas turbine (1) including a compressor (2) for compressing air, a combustor (3) for generating combustion gas by a combustion reaction between the compressed air from the compressor and fuel, and a turbine (4) driven by the combustion gas from the combustor;
a control device (40) according to any one of (1) to (11) above, configured to control operation of the gas turbine;
Equipped with.

According to the configuration (12) above, during startup of the gas turbine, the rotor speed increase rate set value is increased after the switching timing at which the fuel command value switches from a constant value to a continuous increase. In this way, the speed increase rate set value is set to a relatively low value before the switching timing, and is increased after the switching timing at which the fuel command value begins to continuously increase. This allows the gas turbine to start up in a relatively short time while suppressing a decrease in the fuel-air ratio (F/A ratio) and preventing misfires. In other words, the gas turbine can be started up quickly while preventing misfires.

(13) A method for controlling a gas turbine according to at least one embodiment of the present invention includes:
1. A control method for controlling operation of a gas turbine, comprising:
a fuel command value calculation step of calculating a fuel command value to be given to the gas turbine;
a speed increase rate setting step of setting a speed increase rate set value of a rotor of the gas turbine;
Equipped with
In the speed-up rate setting step, during startup of the gas turbine, the speed-up rate set value is increased after a switching timing at which the fuel command value calculated in the fuel command value calculation step switches from a constant value to a continuously increasing value.

According to the method (13) above, during startup of the gas turbine, the rotor speed increase rate set value is increased after the switching timing at which the fuel command value switches from a constant value to a continuous increase. In this way, the speed increase rate set value is set to a relatively low value before the switching timing, and is increased after the switching timing at which the fuel command value begins to continuously increase. This allows the gas turbine to start up in a relatively short time while suppressing a decrease in the fuel-air ratio (F/A ratio) and preventing misfires. In other words, the gas turbine can be started up quickly while preventing misfires.

(14) A control program for a gas turbine according to at least one embodiment of the present invention includes:
A control program for controlling operation of a gas turbine, comprising:
On the computer,
a fuel command value calculation step of calculating a fuel command value to be given to the gas turbine;
a speed-up rate setting step of setting a speed-up rate set value for a rotor of the gas turbine;
configured to cause
In the step of setting a speed-up rate, during startup of the gas turbine, the speed-up rate set value is increased after a switching timing at which the fuel command value calculated in the step of calculating a fuel command value switches from a constant value to a continuously increasing value.

According to the configuration (14) above, during startup of the gas turbine, the rotor speed increase rate set value is increased after the switching timing at which the fuel command value switches from a constant value to a continuous increase. In this way, the speed increase rate set value is set to a relatively low value before the switching timing, and is increased after the switching timing at which the fuel command value begins to continuously increase. This allows the gas turbine to start up in a relatively short time while suppressing a decrease in the fuel-air ratio (F/A ratio) and preventing misfires. In other words, the gas turbine can be started up quickly while preventing misfires.

The above describes embodiments of the present invention, but the present invention is not limited to the above-described embodiments and also includes modifications to the above-described embodiments and appropriate combinations of these embodiments.

In this specification, expressions expressing relative or absolute arrangement such as "in a certain direction,""along a certain direction,""parallel,""orthogonal,""center,""concentric," or "coaxial" not only express such an arrangement strictly, but also express a state in which there is a relative displacement with a tolerance or an angle or distance to the extent that the same function is obtained.
For example, expressions such as "identical,""equal," and "homogeneous" that indicate that something is in an equal state not only indicate a state of strict equality, but also indicate a state in which there is a tolerance or a difference to the extent that the same function is obtained.
Furthermore, in this specification, expressions representing shapes such as a rectangular shape or a cylindrical shape not only represent rectangular shapes or cylindrical shapes in the strict geometric sense, but also represent shapes including uneven portions, chamfered portions, etc., to the extent that the same effect can be obtained.
Furthermore, in this specification, the expressions "comprise,""include," or "have" a component are not exclusive expressions that exclude the presence of other components.

REFERENCE SIGNS LIST 1 Gas turbine 2 Compressor 3 Combustor 4 Turbine 5 Rotating shaft 6 Start-up motor 7 Fuel valve 8 Rotational speed measurement unit 11 Surge prevention control output limiter 12 Gas turbine rotational speed signal 14 Subtractor 16 Function generator 19 Proportional calculator 20 Low value selector 21 Signal generator 22 Adder 23 Low value selector 24 Gas turbine rotational speed control calculation output 25 Generator output control calculation output 26 Gas turbine exhaust gas temperature control calculation output 27 Signal generator 28 Signal generator 29 Gas turbine fuel ignition command signal 30 Gas turbine misfire prevention command signal 33 High value selector 34 Gas turbine control calculation output 40 Control device 42 Fuel command value calculation unit 44 Speed increase rate setting unit 46 Motor output setting unit 48 Memory unit 100 Gas turbine equipment

Claims (14)

A control device for controlling operation of a gas turbine, comprising:
a fuel command value calculation unit for calculating a fuel command value to be given to the gas turbine;
a speed increase rate setting unit for setting a speed increase rate setting value of a rotor of the gas turbine;
Equipped with
the speed-up rate setting unit is configured to increase the speed-up rate set value after a switching timing at which the fuel command value calculated by the fuel command value calculation unit switches from a constant value to a continuously increasing value, during startup of the gas turbine. 2. The gas turbine control device according to claim 1, wherein the speed-up rate setting unit is configured to set a first speed-up rate as the speed-up rate set value before the switching timing, and to increase the speed-up rate set value to a second speed-up rate that is greater than the first speed-up rate after the switching timing. a motor output setting unit for setting an output setting value of a startup motor of the gas turbine,
3. The gas turbine control device according to claim 1, wherein the motor output setting unit is configured to increase the output setting value after the switching timing. 4. The control device for a gas turbine according to claim 3, wherein the motor output setting unit is configured to set a first output as the output set value at a point in time before the switching timing, and to increase the output set value to a second output that is greater than the first output after the switching timing. the speed-up rate setting unit is configured to set a first speed-up rate as the speed-up rate setting value before the switching timing, and to increase the speed-up rate setting value to a second speed-up rate greater than the first speed-up rate after the switching timing,
the motor output setting unit is configured to set a first output as the output set value before the switching timing, and to increase the output set value to a second output greater than the first output after the switching timing;
4. The gas turbine control device according to claim 3, wherein a ratio _rA / _rB of a ratio _rA of the second speed increase rate to the first speed increase rate and a ratio _rB of the second output to the first output is equal to or greater than 0.8 and equal to or less than 1.2. 4. The gas turbine control device according to claim 3, wherein the speed increase rate setting unit and the motor output setting unit are configured to simultaneously increase the speed increase rate setting value and the output setting value after the switching timing. 3. The gas turbine control device according to claim 1, wherein the speed increase rate setting unit starts increasing the speed increase rate set value until the rotation speed of the rotor increases by 300 rpm from the time of the switching timing. the fuel command value calculation unit is configured to calculate, during startup of the gas turbine, a larger one of a first command value that is a constant value and a second command value that is calculated based on a deviation between an actual rotation speed of the rotor and a target rotation speed of the rotor, as the fuel command value,
3. The gas turbine control device according to claim 1, wherein the switching timing is a timing at which the fuel command value calculated by the fuel command value calculation unit switches from the first command value to the second command value. 9. The gas turbine control device according to claim 8, wherein the fuel command value calculation unit is configured to calculate the target rotation speed of the rotor based on the actual rotation speed of the rotor and the speed increase rate set value. 9. The gas turbine control device according to claim 8, wherein the speed-up rate setting unit is configured to set a first speed-up rate as the speed-up rate set value at a first time point before the switching timing, during startup of the gas turbine, and to set a third speed-up rate larger than the first speed-up rate as the speed-up rate set value at a second time point before the first time point. A control device for controlling operation of a gas turbine, comprising:
a fuel command value calculation unit for calculating a fuel command value to be given to the gas turbine;
a motor output setting unit for setting an output setting value of the startup motor of the gas turbine;
Equipped with
the motor output setting unit is configured to increase the output set value after a switching timing at which the fuel command value calculated by the fuel command value calculation unit switches from a constant value to a continuously increasing value, during startup of the gas turbine. a gas turbine including a compressor for compressing air, a combustor for generating combustion gas by a combustion reaction between the compressed air from the compressor and fuel, and a turbine driven by the combustion gas from the combustor;
a controller according to claim 1 or 11 configured to control operation of the gas turbine;
A gas turbine facility comprising: 1. A control method for controlling operation of a gas turbine, comprising:
a fuel command value calculation step of calculating a fuel command value to be given to the gas turbine;
a speed increase rate setting step of setting a speed increase rate set value of a rotor of the gas turbine;
Equipped with
the ramp-up rate setting step increasing the ramp-up rate set value after a switching timing at which the fuel command value calculated in the fuel command value calculation step switches from a constant value to a continuously increasing value, during startup of the gas turbine. A control program for controlling operation of a gas turbine, comprising:
On the computer,
a fuel command value calculation step of calculating a fuel command value to be given to the gas turbine;
a speed-up rate setting step of setting a speed-up rate set value for a rotor of the gas turbine;
configured to cause
a control program for a gas turbine, wherein, in the speed-up rate setting step, during startup of the gas turbine, the speed-up rate set value is increased after a switching timing at which the fuel command value calculated in the fuel command value calculation step switches from being constant to continuously increasing.