Control device for gas turbine, gas turbine system, control method for gas turbine and control program for gas turbine

Abstract

A control device for a gas turbine is a control device for controlling the operation of the gas turbine, comprising: a fuel setpoint calculation unit for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting unit for setting an acceleration rate setpoint of a rotor of the gas turbine. The acceleration rate setting unit is configured to increase the acceleration rate setpoint during the start-up of the gas turbine and after a switching point at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from a constant to a continuous increase.

Description

TECHNICAL FIELD

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

[0002] This application claims priority to Japanese Patent Application No. 2022-110230, filed on July 8, 2022, the contents of which are incorporated herein by reference. BACKGROUND

[0003] When a gas turbine is started, after the fuel is ignited in a combustion chamber, a rotor is accelerated until the rotor speed reaches a predetermined speed (e.g. a rated speed).

[0004] For example, Patent Document 1 describes that a rotor speed is increased at a predetermined rotational acceleration (acceleration rate) determined based on a safety index indicating a relationship between damage to a gas turbine component and a rotational acceleration of a rotor after fuel ignition at the time of starting a gas turbine. Citation listPatent literature

[0005] Patent Document 1: JP2013-221423A SUMMARYTechnical problem

[0006] To shorten the starting time of a gas turbine, it is conceivable to set the acceleration rate (rotational acceleration) of a rotor during gas turbine start-up to a higher value than in the past. However, if the power of a starting motor, etc., is increased more than before to increase the acceleration rate of the rotor during a period immediately after the ignition of the gas turbine when the fuel supply is relatively low, the rotation speed of the rotor increases more than before and the air intake amount in a compressor increases, thereby lowering the fuel-air ratio (F / A ratio) and increasing the possibility of misfire in the combustion chamber.

[0007] In view of the above, it is an object of at least one embodiment of the present invention to provide a control apparatus for a gas turbine, a gas turbine plant, a control method for the gas turbine and a control program for the gas turbine capable of quickly starting the gas turbine while avoiding misfires. Solution to the problem

[0008] A control device for a gas turbine according to at least one embodiment of the present invention is a control device for controlling the operation of a gas turbine, comprising: a fuel setpoint calculation unit for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting unit for setting an acceleration rate setpoint of a rotor of the gas turbine. The acceleration rate setting unit is configured to increase the acceleration rate setpoint during the start-up of the gas turbine and after a switching time at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from a constant increase to a continuous increase.

[0009] Furthermore, a control device for a gas turbine according to at least one embodiment of the present invention is a control device for controlling the operation of a gas turbine, comprising: a fuel setpoint calculation unit for calculating a fuel setpoint to be supplied to the gas turbine; and an engine output setting unit for setting an output setpoint of a starting motor of the gas turbine. The engine output setting unit is configured to increase the output setpoint during start-up of the gas turbine and after a switching time at which the fuel setpoint calculated by the fuel setpoint calculation unit changes from a constant to a continuous increase.

[0010] Furthermore, a gas turbine plant according to at least one embodiment of the present invention comprises: a gas turbine having a compressor for compressing air, a combustor for generating a combustion gas through a combustion reaction between fuel and the compressed air from the compressor, and a turbine configured to be driven by the combustion gas from the combustor; and the control device described above, which is configured to control the operation of the gas turbine.

[0011] Furthermore, a control method for a gas turbine according to at least one embodiment of the present invention is a control method for controlling the operation of the gas turbine, comprising: a fuel setpoint calculation step for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting step for setting an acceleration rate setpoint of a rotor of the gas turbine. The acceleration rate setting step includes increasing the acceleration rate setpoint during the start-up of the gas turbine and after a switching time at which the fuel setpoint calculated in the fuel setpoint calculation step switches from a constant increase to a continuous increase.

[0012] Furthermore, a control program for a gas turbine according to at least one embodiment of the present invention is a control program for controlling the operation of a gas turbine, the control program being configured to cause a computer to execute: a fuel setpoint calculation process for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate adjustment process for adjusting an acceleration rate setpoint of a rotor of the gas turbine. The acceleration rate adjustment process includes increasing the acceleration rate setpoint during the start-up of the gas turbine and after a switching time at which the fuel setpoint calculated in the fuel setpoint calculation process switches from a constant increase to a continuous increase. Beneficial effects

[0013] According to at least one embodiment of the present invention, a control apparatus for a gas turbine, a gas turbine plant, a control method for the gas turbine, and a control program for the gas turbine are provided, which are capable of quickly starting the gas turbine while suppressing misfires. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic configuration diagram of a gas turbine plant having a control device according to an embodiment. Fig. 2 is a schematic configuration diagram of the control device according to an embodiment. Fig. 3 is a block diagram showing arithmetic logic of the control device according to an embodiment. Fig. Figure 4 is a graph showing an example of a relationship between a rotor speed and an acceleration rate command when starting a gas turbine. Fig. Figure 5 is a graph showing an example of a relationship between the rotor speed and an output command of a starting motor when starting the gas turbine. Fig. Figure 6 is a graph showing an example of the relationship between the rotor speed and the acceleration rate command when starting the gas turbine. Fig. 7 is a graph showing an example of temporal variations of the acceleration rate command, the output command of a starting motor, the rotor speed, a fuel command, an exhaust gas temperature, and an actual acceleration rate of a rotor at the start-up of the gas turbine. DETAILED DESCRIPTION

[0014] Some embodiments of the present invention will be described below with reference to the accompanying drawings. However, unless specifically indicated, dimensions, materials, shapes, relative positions, and the like of components described or shown in the drawings are intended to be interpreted as illustrative embodiments only and are not intended to limit the scope of the present invention. (Configuration of the gas turbine plant)

[0015] Fig. 1 is a schematic configuration diagram of a gas turbine plant with a control device according to an embodiment. As shown in Fig. 1, a gas turbine plant 100 comprises a gas turbine 1 and a control device 40 for controlling the operation of the gas turbine 1.

[0016] The gas turbine 1 comprises a compressor 2 for compressing air, a combustion chamber 3 for burning fuel (e.g., natural gas, etc.) to produce a combustion gas, and a turbine 4 configured to be rotated by the combustion gas. The compressor 2 and the turbine 4 are connected via a rotating shaft 5.

[0017] The fuel (e.g., natural gas, etc.) is supplied to the combustion chamber 3, and the compressed air from the compressor 2 is fed into the combustion chamber 3. The fuel is combusted with this compressed air as an oxidizer to generate the combustion gas. The flow rate of the fuel supplied to the combustion chamber 3 can be adjusted via a fuel valve 7.

[0018] The combustion gas generated in the combustion chamber 3 is introduced into the turbine 4 to rotate the turbine 4. The combustion gas that has completed its work in the turbine 4 is discharged from the turbine 4 as exhaust gas. A generator (not shown) can be connected to the turbine 4 via the rotating shaft 5 so that the generator can be driven by the turbine 4 to generate electrical energy.

[0019] As in Fig. As shown in Figure 1, the gas turbine 1 may include a starting motor 6. The starting motor 6 may supply rotational energy to the rotating shaft 5 of the gas turbine 1 to cause the rotating shaft 5 to rotate. The starting motor 6 may be configured to assist the rotational drive of the gas turbine 1 until the gas turbine 1 can rotate independently using its own combustion energy upon starting the gas turbine 1.

[0020] In some embodiments, the above-described generator, which is connected to the gas turbine 1 via the rotating shaft 5, can be supplied with electrical power and function as a starting motor 6. In this case, to rotate the generator as an electric motor, electrical power with variable voltage and variable frequency can be supplied to the generator by a frequency converter such as a static frequency converter (SFC).

[0021] The gas turbine 1 may include a speed measuring part 8 for measuring the speed of a rotating shaft 5 of the gas turbine 1 (rotational speed of a rotor of the gas turbine 1). The speed measuring part 8 may include a speed sensor, such as an encoder. A signal indicating a measured value of the rotor speed by the speed measuring part 8 is sent to the control device 40. (Control device configuration)

[0022] Fig. 2 is a schematic configuration diagram of the control device 40 according to an embodiment. As shown in Fig. As shown in Figure 2, the control device 40 includes a fuel setpoint calculation unit 42 and an acceleration rate setting unit 44. The control device 40 may include a motor output setting unit 46 and / or a storage unit 48. The control device 40 is configured to receive a signal indicating a measured value (actual speed) of the rotor speed from the speed measuring part 8 and process the signal. An arithmetic result in the control device 40 may be sent to the fuel valve 7 or the starting motor 6, and the fuel valve 7 or the starting motor 6 may operate based on the arithmetic result.

[0023] The fuel setpoint calculation unit 42 is configured to calculate a fuel setpoint FI supplied to the gas turbine 1. Based on this fuel setpoint FI, the opening degree of the fuel valve 7 is adjusted. The control device 40 may be configured to adjust the opening degree of the fuel valve 7 to correspond to the fuel setpoint FI.

[0024] The acceleration rate setting unit 44 is configured to set a target acceleration rate of the rotor during startup of the gas turbine 1. The acceleration rate setting unit 44 may be configured to set a different target acceleration rate depending on the rotational speed (a rated rotational speed, etc.) during operation after startup of the gas turbine 1. The target acceleration rate may be used for calculating the fuel setpoint FI by the fuel setpoint calculation unit 42.

[0025] The motor output setting unit 46 is configured to set an output setpoint of the starting motor 6 during the start-up of the gas turbine 1. The output setpoint set by the motor output setting unit 46 is sent to the starting motor 6, and the starting motor 6 operates to receive the set output. When the generator is used as the starting motor 6 together with the frequency converter such as the SFC, the motor output setting unit 46 can be configured to set an output setpoint of the frequency converter as the output setpoint of the starting motor 6.

[0026] The storage unit 48 is configured to store inputs and outputs to the control device 40 or the arithmetic result, etc., in the control device 40. The acceleration rate setting unit 44 may be configured to read and set the acceleration rate set value stored in the storage unit 48. The motor output setting unit 46 may be configured to read and set the output set value stored in the storage unit 48. The storage unit 48 may be a main storage device or an auxiliary storage device of a computer constituting the control device 40.

[0027] The control device 40 includes a computer having a processor (e.g., CPU), a main memory device (e.g., RAM), an auxiliary memory device, an interface, and the like. The control device 40 is configured to receive the signal from the speed measuring part 8 via an interface. The processor is configured to process the thus received signal. Furthermore, the processor is configured to process programs loaded into the main memory device. This realizes the function of each of the above-described functional units (the fuel setpoint calculation unit 42, the acceleration rate setting unit 44, and the engine output setting unit 46).

[0028] The processing of content in the control device 40 takes place in the form of programs that are executed by the processor. The programs can be stored, for example, in auxiliary memory. When the programs are executed, these programs are loaded into the main memory device. The processor is configured to read the programs from the main memory device in order to execute the instructions contained in the programs.

[0029] Fig. 3 is a block diagram showing the arithmetic logic of the fuel setpoint calculation unit 42 of the control device 40 according to an embodiment. The fuel setpoint calculation unit 42 calculates and outputs the fuel setpoint FI to be supplied to the gas turbine 1.

[0030] In Fig. 3, reference numeral 11 denotes an output limiter for the overvoltage protection control, reference numeral 12 a gas turbine speed signal, reference numeral 14 a subtractor, reference numeral 16 a function generator, reference numeral 19 a proportional arithmetic unit, reference numeral 20 a low-value selector, reference numeral 21 denotes a signal generator, reference numeral 22 denotes an adder, reference numeral 23 denotes a low-value selector, reference numeral 24 denotes an arithmetic output for controlling the gas turbine speed, reference numeral 25 denotes an arithmetic output for controlling the generator power, reference numeral 26 denotes an arithmetic output for controlling the gas turbine exhaust gas temperature, reference numerals 27 and 28 denote signal generators, reference numeral 29 denotes a gas turbine fuel ignition command signal, reference numeral 30 denotes a Gas turbine misfire prevention command signal,Reference numerals 31 and 32 denote contact points that close when the respective signals 29 and 30 are turned on, reference numeral 33 denotes a high-value selector, and reference numeral 34 denotes an arithmetic output of the gas turbine control (fuel setpoint output).

[0031] In parts of reference numerals 11 to 22, the fuel flow rate (second target value F2) is calculated and output based on the rotational speed, etc. of the rotor of the gas turbine 1, as described later. The gas turbine speed control arithmetic output 24 outputs the fuel flow rate in a state where the gas turbine is close to the rated speed. The generator power control arithmetic output 25 outputs the fuel flow rate in a state where the generator of the gas turbine 1 is connected to and transmitting power to a power grid. The gas turbine exhaust gas temperature control arithmetic output 26 outputs the fuel flow rate determined based on the exhaust gas temperature of the gas turbine so that a turbine blade, etc. of the gas turbine does not become abnormally hot. The low-value selector 23 selects the lowest value among these outputs and outputs it to the high-value selector 33.

[0032] When starting the gas turbine 1, the fuel flow rate (second setpoint F2) from the parts of reference numerals 11 to 22 is the lowest value among the outputs described above and is therefore selected by the low-value selector 23 and output to the high-value selector 33.

[0033] Meanwhile, when starting the gas turbine 1, the output of the signal generator 27 when the gas turbine fuel ignition command signal 29 is applied, or the output of the signal generator 28 when the gas turbine misfire prevention command signal 30 is applied, is input to the high-value selector 33. The output (first set value F1) of the signal generator 27 or the signal generator 28 is a constant value.

[0034] The high-value selector 33 selects the highest value from a plurality of inputs and outputs it. When the gas turbine 1 is started, the larger of the output signal (first setpoint F1) of the signal generator 27 and the fuel flow rate (second setpoint F2) from the parts of reference numerals 11 to 22 is selected and output to the arithmetic output of the gas turbine controller 34. That is, when the gas turbine 1 is started, the larger of the output signal (first setpoint F1) of the signal generator 27 and the fuel flow rate (second setpoint F2) from the parts of reference numerals 11 to 22 is calculated as the fuel setpoint FI.

[0035] The arithmetic in the parts of reference numerals 11 to 22 is described below. The output signal of the output limiter of the overvoltage protection controller 11 is obtained by the rotation speed (rotor speed) of the gas turbine 1 and a discharge pressure of the compressor. The gas turbine speed signal 12 is a signal received from the speed measuring part 8 (a signal indicating the actual rotor speed of the gas turbine 1) and is input to the subtractor 14 and the function generator 16.

[0036] The function generator 16 receives the actual speed of the rotor from the gas turbine speed signal 12 and also receives the acceleration rate setpoint from the acceleration rate setting unit 44 (see Fig. 2) and calculates a target speed of the rotor of the gas turbine 1 based on the actual rotor speed and the acceleration rate setpoint. The function generator 16 can calculate the target speed by adding an increase in speed corresponding to the acceleration rate to the actual rotor speed.

[0037] The subtractor 14 subtracts the gas turbine speed signal 12 from the output of the function generator 16 and passes the result to the proportional arithmetic unit 19. The proportional arithmetic unit 19 multiplies this by an internally defined coefficient and outputs the result. The low-value selector 20 outputs a value corresponding to the lower of the output of the proportional arithmetic unit 19 and the output of the signal generator 21. The output signal of the signal generator 21 is normally zero, so the output signal of the low-value selector 20 is always negative. The adder 22 outputs a value resulting from the addition of the output signal of the output limiter of the overvoltage protection controller 11 and the output signal of the low-value selector 20. In the parts of reference numerals 11 to 22, the output (second setpoint) is determined in terms of fuel flow, i.e., based on the engine speed, etc.of gas turbine 1. (Gas turbine control sequence)

[0038] Next, a control method for the gas turbine 1 according to some embodiments will be described. A case where the above-described gas turbine 1 is controlled using the above-described control device 40 will be described below. However, in some embodiments, the control method for the gas turbine may be performed using a different device, or some or all of the processes described below may be performed manually.

[0039] Fig. 4 and Fig. 6 are each a graph showing an example of a relationship between the rotor speed and the acceleration rate command value when starting the gas turbine. Fig. Figure 5 is a graph showing an example of a relationship between the rotor speed and the starting motor output setpoint when starting the gas turbine. Fig. 7 is a graph showing an example of temporal variations of the acceleration rate command value, the starting motor output command value, the rotor speed (actual speed) of the rotor, the fuel command value, the exhaust gas temperature, and an actual acceleration rate of the rotor when starting the gas turbine in a variety of cases (cases A to D).

[0040] In Fig. 4 to 7, R0 is a rotor speed at the time of ignition of the gas turbine 1 (time t0 in Fig. 7), and R_rated is a rotation speed (e.g., a rated speed) during operation after starting the gas turbine 1. The starting of the gas turbine 1 includes the period from the start of rotation of the rotor of the gas turbine 1 until the rotor speed increases to a predetermined speed (e.g., the rated speed).

[0041] First, the control flow in case C, which is a conventional typical example, is described with reference to Fig. 7 described.

[0042] In case C, the rotor of gas turbine 1 is rotated by start-up motor 6 in a period before time t0. At this time, an output setpoint of start-up motor 6 is set to M0.

[0043] At time t0, the fuel in the combustion chamber 3 is ignited. The rotor speed at this time is R0. At time t0, the acceleration rate setpoint and the output setpoint of the starting motor 6 are set to predetermined values ​​(e.g., values ​​determined in advance according to the speed, etc., after starting the gas turbine 1). In case C, an acceleration rate setpoint is set to A1, and an output setpoint of the starting motor 6 is set to M1.

[0044] After time t0, the fuel setpoint FI calculated by the fuel setpoint calculation unit 42 is constant. That is, the fuel setpoint calculation unit 42 calculates, as the fuel setpoint FI, the first setpoint F1, which is the larger of the above-described first setpoint F1 (constant value) and the second setpoint F2 calculated from the rotor speed, etc. Fuel is supplied to the gas turbine 1 based on this fuel setpoint FI, and the rotor speed increases to a certain extent, as shown in the graph.

[0045] At time t6, the fuel setpoint switches from a constant increase to a continuous increase. That is, the fuel setpoint FI calculated by the fuel setpoint calculation unit 42 switches from the first setpoint F1, which is the constant value, to the second setpoint F2, which is calculated based on the rotor speed, etc. The time at which the fuel setpoint switches from a constant increase to a continuous increase is called the switching time.

[0046] Even after time t6, the acceleration rate setpoint remains at A1 and the output setpoint of starting motor 6 remains at M1. After time t6, the rotor speed increases at a substantially constant rate. This rate corresponds to the acceleration rate setpoint A1. The rotor speed is increased until the rotor speed reaches the specified speed (e.g., the rated speed).

[0047] Next, the control flow of Case A according to an embodiment will be described. The control flow in Case A is the same as in Case C until the switching time (time t6 in Cases A and C) at which the fuel setpoint switches from a constant to a continuous increase. However, in Case A, after the switching time, the acceleration rate setting unit 44 increases the acceleration rate setpoint from A1 (first acceleration rate) to A2 (second acceleration rate). In the case shown in the graph of Fig. In the example shown in Figure 7, the acceleration rate command value is increased from A1 to A2 between time t6 (the switching time) and time t7, and the acceleration rate command value is maintained at A2 after time t7.

[0048] The acceleration rate setting unit 44 can determine the acceleration rate target value based on the rotor speed. That is, as shown in Fig. 4, the acceleration rate setpoint can be set to A1 until the rotor speed R A1 reached, and as soon as the rotor speed R A1 reached, the acceleration rate setpoint can be increased from A1 to A2. Where R A1 a rotational speed that is not less than the rotational speed at which the switching time occurs. Fig. In the example shown in Figure 4, the acceleration rate setpoint is increased from A1 to A2, while the rotor speed changes from R A1 on R A2 changes.

[0049] In the above-described case A, the acceleration rate command value after the switching timing is A2 and is larger than A1 in the case C. Therefore, in the case A, the gradient of the increase of the rotor speed after the switching timing is larger than in the case C. Therefore, a time required for the rotor speed to increase to the predetermined speed is shortened, and a start time of the gas turbine 1 is shortened.

[0050] To shorten the start-up time of gas turbine 1, as shown in Case D, the acceleration rate setpoint could be set to a relatively large value (A2) from the time of ignition (time t0). However, if, as in Case D, the acceleration rate setpoint is uniformly set to a large value (A2), the rotor speed increases rapidly, and the fuel-air ratio (F / A ratio) decreases due to an increase in the intake air volume in compressor 2, thereby increasing the possibility of misfire in combustion chamber 3. The diagram in Fig. Figure 7 shows that after ignition at time t0, the increase in exhaust gas temperature in case D remains small and decreases due to the decrease in the fuel-air ratio (F / A ratio) resulting from the sharp increase in engine speed.

[0051] In contrast, in Case A described above, it is possible to suppress misfires by suppressing the decrease of the fuel-air ratio (F / A ratio) because the acceleration rate target value is set to a relatively low value (A1) before the shift timing and the acceleration rate target value is increased after the shift timing at which the fuel target value starts to increase continuously.

[0052] Therefore, in case A described above, the gas turbine can be started quickly while misfires are suppressed.

[0053] If the rotor speed of compressor 2 is maintained within a predetermined speed range, stall may occur and the blade may be damaged. In this regard, in Case A described above, since the acceleration rate command is relatively increased after the switching time point where the fuel command changes from constant to continuous increase, it is possible to quickly traverse the speed range where rotational stall occurs in compressor 2. Therefore, the gas turbine can be started quickly while suppressing the occurrence of stall in the compressor.

[0054] In some embodiments, e.g., as in case A described above, the first acceleration rate A1 is set as the acceleration rate target value at a time before the switching time, and the acceleration rate target value is increased to the second acceleration rate A2 after the switching time. In some embodiments, a ratio r A the second acceleration rate A2 to the first acceleration rate (r A =A2 / A1) must be at least 1.2 or at most 1.5.

[0055] After the switching timing, by increasing the acceleration rate command value of the rotor from the value (first acceleration rate A1) before the switching timing to the second acceleration rate A2, it is possible to start the gas turbine 1 in a relatively short time while more effectively suppressing misfires due to the reduction of the fuel-air ratio.

[0056] In case A in Fig. 7, the motor output adjustment unit 46 increases the output setpoint of the starting motor 6 from M1 (first output) to M2 (second output) after the switching time. In the position shown in the graph of Fig. In the example shown in Figure 7, the output setpoint is increased from M1 to M2 between time t6 (the switching time) and time t7, and the output setpoint is maintained at M2 after time t7.

[0057] The motor output setting unit 46 can determine the output setpoint based on the rotor speed. That is, as shown in Fig. 5, the output setpoint can be set to M1 until the rotor speed R M1 reached, and as soon as the rotor speed R M1 reached, the output setpoint can be increased from M1 to M2. Where R M1 a rotational speed that is not less than the rotational speed at which the switching time occurs. Fig. In the example shown in Figure 5, the output setpoint is increased from M1 to M2, while the rotor speed changes from R M1 on R M2 changes.

[0058] In case A described above, the output setpoint of the starting motor 6 is increased during the start-up of the gas turbine 1 and after the switching time at which the fuel setpoint switches from constant to continuous increase. Thus, by increasing the output setpoint of the starting motor together with the acceleration setpoint after the switching time, the rotor can be accelerated while suppressing the increase in the fuel setpoint. This makes it possible to suppress a temperature increase of the combustion gas introduced from the combustor 3 into the turbine 4 (i.e., the increase in the exhaust gas temperature that occurs in Fig. 7 is also suppressed). Therefore, the gas turbine 1 can be started quickly while suppressing misfires and while suppressing damage to the turbine component caused by the high-temperature combustion gas.

[0059] In some embodiments, e.g., as in case A described above, the first output M1 is set as the output setpoint of the starting motor 6 at the time before the switching time, and the output setpoint is increased to the second output M2 after the switching time. In some embodiments, the ratio r B between the second output M2 and the first output (r B =M2 / M1) must be at least 1.2 or at most 1.5.

[0060] After the switching timing, the temperature rise of the combustion gas introduced from the combustor 3 into the turbine 4 can be effectively suppressed by increasing the output setpoint of the starting motor 6 from the value (first output M1) before the switching timing to the second output M2. Therefore, the gas turbine 1 can be started quickly while suppressing misfires, while effectively suppressing damage to the turbine component caused by the high-temperature combustion gas.

[0061] In some embodiments, a ratio r / r AB the ratio r A the second acceleration rate A2 to the first acceleration rate A1 to the ratio r B of the second output M2 to the first output M1, described above, at least 0.8 and at most 1.2.

[0062] In the above-described embodiment, the acceleration setpoint and the starting motor output setpoint are increased by the same amount during the start-up of the gas turbine 1 and after the switching time at which the fuel setpoint switches from constant to continuous increase. Therefore, the gas turbine 1 can be started quickly while effectively suppressing misfires due to the decrease in the fuel-air ratio and damage to the turbine component due to the increase in combustion gas temperature.

[0063] In some embodiments, the acceleration rate setting unit 44 and the motor output setting unit 46 are configured to increase the acceleration rate setpoint and the output setpoint simultaneously after the switching time. For example, in case A in Fig. 7 the acceleration rate setpoint and the output setpoint are increased simultaneously between times t6 and t7.

[0064] In the above-described embodiment, the acceleration setpoint and the starting motor output setpoint are increased simultaneously during the start-up of the gas turbine 1 and after the switching time at which the fuel setpoint switches from constant to continuous increase. Therefore, the gas turbine 1 can be started quickly while effectively suppressing misfires due to the decrease in the fuel-air ratio and damage to the turbine component due to the increase in combustion gas temperature.

[0065] In some embodiments, the acceleration rate setting unit 44 is configured to start increasing the acceleration rate setpoint at the time when the rotor speed increases by 300 rpm from the switching time. In case A in Fig. 7, the acceleration rate setpoint begins to increase at the same time as the switching time (time t6).

[0066] In the embodiment described above, since the acceleration rate command value starts to increase within the short period of time from the time of the switching timing at which the fuel command value switches from a constant increase to a continuous increase until the rotor speed increases by 300 rpm, it is possible to start the gas turbine 1 more quickly while suppressing misfires at the time of starting the gas turbine 1 and after the switching timing.

[0067] In some embodiments, the motor output adjustment unit 46 is configured to start increasing the output setpoint of the starting motor 6 when the rotor speed increases by 300 rpm from the switching time. In case A in Fig. 7 the increase of the output setpoint begins at the same time as the switching time (time t6).

[0068] In the above-described embodiment, since the output command value of the starting motor 6 starts to increase within the short period of time from the time of the switching timing at which the fuel command value switches from a constant increase to a continuous increase until the rotor speed increases by 300 rpm, it is possible to start the gas turbine more quickly during the start-up of the gas turbine 1 and after the switching timing while suppressing the damage of the turbine component due to the temperature increase of the combustion gas.

[0069] Next, the control flow of Case B according to one embodiment will be described. The control flow in Case B is the same as in Case A, in that the acceleration rate setpoint increases from A1 (first acceleration rate) to A2 (second acceleration rate) after the switching time at which the fuel setpoint switches from constant to continuous increase (the time of t6 in Case A, the time of t3 in Case B).

[0070] In case B, during the start-up of the gas turbine 1, the first acceleration rate A1 is set as the acceleration rate target value at a time before the switching time (time t3), and at a time before the time described above, a third acceleration rate A3, which is greater than the first acceleration rate A1, is set as the acceleration rate target value. In the case shown in the diagram of Fig. In the example shown in Figure 7, after the ignition time (time t0) of gas turbine 1, the acceleration rate setpoint is maintained at A3 until time t1, and the acceleration rate setpoint is decreased from A3 to A1 between times t1 and t2. Then, between times t4 and t5, after the switching time (time t3) has elapsed, the acceleration rate setpoint increases from A1 to A2.

[0071] The acceleration rate setting unit 44 can determine the acceleration rate target value based on the rotor speed. That is, as shown in Fig. 6, the acceleration rate setpoint can be set to A3 until the rotor speed drops from R0 to R A3 increases, and as soon as the rotor speed R A3 reached, the acceleration rate setpoint can be reduced from A3 to A1. In the Fig. In the example shown in Figure 6, the acceleration rate setpoint is reduced from A3 to A1, while the rotor speed changes from R A3 on R A4 Furthermore, the acceleration rate setpoint can be maintained at A1 until the rotor speed changes from R A4 on R A1 increased, and as soon as the rotor speed R A1 reached, the acceleration rate setpoint can be increased from A1 to A2. In the Fig. In the example shown in Figure 6, the acceleration rate setpoint is increased from A1 to A2, while the rotor speed changes from R A1 on R A2 changes.

[0072] In Case B, during the start-up of the gas turbine 1, the third acceleration rate A3, which is greater than the first acceleration rate A1, is set as the acceleration rate command value at a second time point (t0 to t1) before a first time point (times t2 to t3) at which the relatively low first acceleration rate A1 is set as the acceleration rate command value before the switching time point (time t3). Therefore, compared with Case A etc. in which the third acceleration rate A3 is not set, the second command value F2, which is based on a deviation between an actual rotational speed and a commanded rotational speed of the rotor, becomes a larger value. Consequently, it is possible to advance the switching time point at which the second command value F2 becomes greater than the first command value F1, thereby enabling the gas turbine to be started more quickly.

[0073] The third acceleration rate A3 described above can be greater than the second acceleration rate A2 set after the switching time. Since the second setpoint F2, which is based on the deviation between the actual speed and the target speed of the rotor, becomes the larger value, it is possible to further advance the switching time at which the second setpoint F2 becomes greater than the first setpoint F1. This allows the gas turbine to be started more quickly.

[0074] The contents described in the above embodiments are to be understood, for example, as follows.

[0075] (1) A control device (40) for a gas turbine according to at least one embodiment of the present invention is a control device for controlling the operation of the gas turbine (1), comprising: a fuel setpoint calculation unit (42) for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting unit (44) for setting an acceleration rate setpoint of a rotor of the gas turbine. The acceleration rate setting unit is configured to increase the acceleration rate setpoint during the start-up of the gas turbine and after a switching time at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from a constant increase to a continuous increase.

[0076] According to the above configuration (1), the acceleration rate command value of the rotor is increased during the start of the gas turbine and after the switching time point where the fuel command value switches from constant to continuous increase. As described above, since the acceleration rate command value is set to a relatively low value before the switching time point and the acceleration rate command value is increased after the switching time point where the fuel command value starts to continuously increase, it is possible to start the gas turbine in a relatively short time while suppressing misfire by suppressing the decrease in the fuel-air ratio (F / A ratio). That is, the gas turbine can be started quickly while suppressing misfire.

[0077] (2) In some embodiments, in the above configuration (1), the acceleration rate setting unit is configured to set a first acceleration rate (A1) as the acceleration rate target value at a time before the switching time and is configured to increase the acceleration rate target value to a second acceleration rate (A2) that is greater than the first acceleration rate after the switching time.

[0078] According to the above configuration (2), after the switching timing, it is possible to start the gas turbine in a relatively short time while more effectively suppressing the misfire due to the decrease in the fuel-air ratio because the acceleration rate command value of the rotor is increased from the value (first acceleration rate) before the switching timing to the second acceleration rate.

[0079] (3) In some embodiments, the control device for the gas turbine in the above configuration (1) or (2) includes a motor output adjustment unit (46) for adjusting an output target value of a starting motor of the gas turbine. The motor output adjustment unit is configured to increase the output target value after the switching timing.

[0080] According to the above configuration (3), the starting motor output setpoint is increased during gas turbine startup and after the switching point at which the fuel setpoint switches from constant increase to continuous increase. After the switching point, by increasing the starting motor output setpoint along with the acceleration setpoint, the rotor can be accelerated while suppressing the increase in the fuel setpoint. This makes it possible to suppress the temperature increase of the combustion gas introduced from the combustor into the turbine. Therefore, the gas turbine can be started quickly while suppressing misfire and damage to the turbine components caused by the high combustion gas temperature.

[0081] (4) In some embodiments, in the above configuration (3), the motor output setting unit is configured to set a first output (M1) as the output target value at a time before the switching time and is configured to increase the output target value to a second output (M2) that is larger than the first output after the switching time.

[0082] According to the above configuration (4), after the switching timing, it is possible to effectively suppress the temperature rise of the combustion gas introduced from the combustor into the turbine because the output setpoint of the starting motor is increased from the value (first output) before the switching timing to the second output. Therefore, the gas turbine can be started quickly while suppressing misfire and effectively preventing damage to the turbine component caused by the high-temperature combustion gas.

[0083] (5) In some embodiments, in the above configuration (3) or (4), the acceleration rate setting unit is configured to set a first acceleration rate as the acceleration rate target value at a time before the switching time and is configured to increase the acceleration rate target value to a second acceleration rate greater than the first acceleration rate after the switching time, the motor output setting unit is configured to set a first output as the output target value at a time before the switching time and is configured to increase the output target value to a second output greater than the first output after the switching time, and a ratio r A / r B a ratio r A the second acceleration rate to the first acceleration rate to a ratio r Bof the second output to the first output is at least 0.8 and at most 1.2.

[0084] According to the above configuration (5), the acceleration setpoint and the starting motor output setpoint are increased by the same amount during gas turbine startup and after the fuel setpoint switches from constant to continuous increase. Therefore, the gas turbine can be started quickly while effectively suppressing misfires due to the decrease in the fuel-air ratio and damage to turbine components due to the increase in combustion gas temperature.

[0085] (6) In some embodiments, in any one of the above configurations (3) to (5), the acceleration rate setting unit and the motor output setting unit are configured to increase the acceleration rate command value and the output command value simultaneously after the switching timing.

[0086] According to the above configuration (6), the acceleration setpoint and the starting motor output setpoint are increased simultaneously during gas turbine startup and after the fuel setpoint switches from constant to continuous increase. Therefore, the gas turbine can be started quickly while effectively suppressing misfires due to a decrease in the fuel-air ratio and turbine component damage due to a rise in combustion gas temperature.

[0087] (7) In some embodiments, in any one of the above configurations (1) to (6), the acceleration rate setting unit is configured to start increasing the acceleration rate command value at a time point when the rotor speed increases by 300 rpm from a time point of the switching timing.

[0088] According to the above configuration (7), it is possible to start the gas turbine faster and suppress misfires at the same time during the start-up of the gas turbine and after the switching timing because the acceleration rate command value starts to increase within the short period from the time of the switching timing at which the fuel command value switches from a constant to a continuous increase until the rotor speed increases by 300 rpm.

[0089] (8) In some embodiments, in any one of the above configurations (1) to (7), the fuel setpoint calculation unit is configured to calculate, as the fuel setpoint, a larger one of a first setpoint, which is a constant value, and a second setpoint, which is calculated based on a deviation between an actual rotational speed and a target rotational speed of the rotor, during the start of the gas turbine, and the switching timing is a timing at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from the first setpoint to the second setpoint.

[0090] According to the above configuration (8), the acceleration rate command value is increased during the start of the gas turbine and after the switching timing at which the fuel command value switches from the first command value, which is the constant value, to the second command value based on the deviation between the actual rotational speed and the target rotational speed of the rotor. As described above, since the acceleration rate command value is set to a relatively low value before the switching timing and the acceleration rate command value is increased after the switching timing at which the fuel command value starts to continuously increase, it is possible to start the gas turbine in a relatively short time while suppressing misfire by suppressing the decrease in the fuel-air ratio (F / A ratio).

[0091] (9) In some embodiments, in the above configuration (8), the fuel setpoint calculation unit is configured to calculate the setpoint rotational speed of the rotor based on the actual rotational speed of the rotor and the acceleration rate setpoint.

[0092] According to the above configuration (9), since the target rotor speed is calculated based on the actual rotor speed and the acceleration rate setpoint, the second fuel setpoint corresponds to the rotor acceleration rate setpoint. Thus, the second setpoint can be calculated according to the set acceleration rate value.

[0093] (10) In some embodiments, in the above configuration (8) or (9), the acceleration rate setting unit is configured to set a first acceleration rate (A1) as the acceleration rate target value at a first time point before the switching time point, and is configured to set a third acceleration rate (A3) greater than the first acceleration rate as the acceleration rate target value at a second time point before the first time point during the start of the gas turbine.

[0094] According to the above configuration (10), during the start-up of the gas turbine, the third acceleration rate, which is greater than the first acceleration rate, is set as the acceleration rate target value at the second time point before the first time point at which the relatively low first acceleration rate is set as the acceleration rate target value before the switching time point. Consequently, it is possible to advance the switching time point at which the second target value based on the deviation between the actual rotational speed and the target rotational speed of the rotor becomes greater than the first target value, thereby enabling the gas turbine to start faster.

[0095] (11) A control device (40) for a gas turbine according to at least one embodiment of the present invention is a control device for controlling the operation of a gas turbine, including: a fuel setpoint calculation unit (42) for calculating a fuel setpoint to be supplied to the gas turbine; and a motor output adjustment unit (46) for adjusting an output setpoint of a starting motor of the gas turbine. The motor output adjustment unit is configured to increase the output setpoint during start-up of the gas turbine and after a switching point at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from a constant increase to a continuous increase.

[0096] According to the above configuration (11), the starting motor output setpoint is increased during gas turbine startup and after the switching point at which the fuel setpoint switches from constant increase to continuous increase. After the switching point, increasing the starting motor output setpoint can accelerate the rotor while suppressing the increase in the fuel setpoint. This makes it possible to suppress the temperature increase of the combustion gas introduced from the combustor into the turbine. This can suppress damage to the turbine component caused by the high-temperature combustion gas.

[0097] (12) A gas turbine plant (100) according to at least one embodiment of the present invention comprises: a gas turbine (1) comprising a compressor (2) for compressing air, a combustion chamber (3) for generating a combustion gas through a combustion reaction between fuel and the compressed air from the compressor, and a turbine (4) configured to be driven by the combustion gas from the combustion chamber; and the control device (40) according to any one of the above (1) to (11), which is configured to control the operation of the gas turbine.

[0098] According to the above configuration (12), the acceleration rate command value of the rotor is increased during the start of the gas turbine and after the switching time point where the fuel command value switches from constant to continuous increase. As described above, since the acceleration rate command value is set to a relatively low value before the switching time point and the acceleration rate command value is increased after the switching time point where the fuel command value starts to continuously increase, it is possible to start the gas turbine in a relatively short time while suppressing misfire by suppressing the decrease in the fuel-air ratio (F / A ratio). That is, the gas turbine can be started quickly while suppressing misfire.

[0099] (13) A control method for a gas turbine according to at least one embodiment of the present invention is a control method for controlling the operation of a gas turbine, comprising: a fuel setpoint calculation step for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting step for setting an acceleration rate setpoint of a rotor of the gas turbine. The acceleration rate setting step includes increasing the acceleration rate setpoint during the start-up of the gas turbine and after a switching time at which the fuel setpoint calculated in the fuel setpoint calculation step switches from a constant increase to a continuous increase.

[0100] According to the above method (13), the acceleration rate command value of the rotor is increased during the start of the gas turbine and after the switching time point at which the fuel command value switches from constant to continuous increase. As described above, since the acceleration rate command value is set to a relatively low value before the switching time point and the acceleration rate command value is increased after the switching time point at which the fuel command value starts to continuously increase, it is possible to start the gas turbine in a relatively short time while suppressing misfire by suppressing the decrease in the fuel-air ratio (F / A ratio). That is, the gas turbine can be started quickly while suppressing misfire.

[0101] (14) A control program for a gas turbine according to at least one embodiment of the present invention is a control program for controlling the operation of a gas turbine, the control program being configured to cause a computer to execute: a fuel setpoint calculation process for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting process for setting an acceleration rate setpoint of a rotor of the gas turbine. The acceleration rate setting process includes increasing the acceleration rate setpoint during the start-up of the gas turbine and after a switching time at which the fuel setpoint calculated in the fuel setpoint calculation process switches from a constant increase to a continuous increase.

[0102] According to the above configuration (14), the acceleration rate command value of the rotor is increased during the start of the gas turbine and after the switching time point at which the fuel command value switches from constant to continuous increase. As described above, since the acceleration rate command value is set to a relatively low value before the switching time point and the acceleration rate command value is increased after the switching time point at which the fuel command value starts to continuously increase, it is possible to start the gas turbine in a relatively short time while suppressing misfire by suppressing the decrease in the fuel-air ratio (F / A ratio). That is, the gas turbine can be started quickly while suppressing misfire.

[0103] Embodiments of the present invention have been described above in detail, but the present invention is not limited thereto and also includes an embodiment obtained by modifying the above-described embodiments and an embodiment obtained by combining these embodiments as appropriate.

[0104] Furthermore, in this specification, an expression of relative or absolute arrangement such as "in one direction", "along one direction", "parallel", "orthogonal", "centered", "concentric" and "coaxial" should not be construed to mean only the arrangement in a strictly literal sense, but also to include a state in which the arrangement is relatively shifted by a tolerance or by an angle or a distance, whereby it is possible to achieve the same function.

[0105] For example, an expression for an equal state such as “the same”, “equal” and “uniform” should not be interpreted as indicating only the state in which the characteristic is exactly the same, but also a state in which there is a tolerance or a difference with which the same function can still be achieved.

[0106] Furthermore, a shape such as a rectangular shape or a cylindrical shape does not only mean the geometrically strict shape, but also a shape with unevenness or beveled corners within the range where the same effect can be achieved.

[0107] Furthermore, in this description, the expressions “comprising”, “including” or “with” a constitutional element are not exclusive expressions that exclude the presence of other constitutional elements. Reference character list 1 gas turbine 2 compressor 3 combustion chamber 4 turbines 5 Rotation shaft 6 Run-up motor 7 Fuel valve 8 Speed ​​measuring unit 11 Output limiter of the overvoltage protection control 12 Gas turbine speed signal 14 subtractors 16 Function generator 19 Proportional calculator 20 Low-value selector 21 Signal generator 22 adders 23 Low-value selector 24 Arithmetic output for gas turbine speed control 25 Arithmetic output to control the generator power 26 Arithmetic output for controlling the gas turbine exhaust gas temperature 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 Arithmetic output of the gas turbine control 40 Control device 42 Fuel setpoint calculation unit 44 Acceleration rate adjustment unit 46 Engine output adjustment unit 48 storage units 100 gas turbine plants QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2022-110230

[0002] JP 2013-221423A

[0005]

Claims

[1] Control device for controlling the operation of a gas turbine, comprising: a fuel setpoint calculation unit for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting unit for setting an acceleration rate target value for a rotor of the gas turbine, wherein the acceleration rate setting unit is configured to increase the acceleration rate setpoint during a start-up of the gas turbine and after a switching time at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from a constant increase to a continuous increase. [2] The control device for the gas turbine according to claim 1, wherein the acceleration rate setting unit is configured to set a first acceleration rate as the acceleration rate command value at a time before the switching time and is configured to increase the acceleration rate command value to a second acceleration rate greater than the first acceleration rate after the switching time. [3] A gas turbine control device according to claim 1 or 2, comprising: a motor output setting unit for setting an output setpoint of a starting motor of the gas turbine, wherein the motor output adjustment unit is configured to increase the output setpoint after the switching time. [4] A control device for a gas turbine according to claim 3, wherein the engine output setting unit is configured to set a first output as an output target value at a time before the switching timing and is configured to increase the output target value to a second output that is larger than the first output after the switching timing. [5] Control device for the gas turbine according to claim 3, wherein the acceleration rate setting unit is configured to set a first acceleration rate as the acceleration rate target value at a time before the switching time and is configured to increase the acceleration rate target value to a second acceleration rate that is greater than the first acceleration rate after the switching time, wherein the motor output setting unit is configured to set a first output as the output setpoint at a time before the switching time and is configured to increase the output setpoint to a second output that is greater than the first output after the switching time, and where a ratio r A / r B a ratio r A the second acceleration rate to the first acceleration rate to a ratio r B of the second output to the first output is at least 0.8 and at most 1.

2. [6] The control device for the gas turbine according to claim 3, wherein the acceleration rate setting unit and the engine output setting unit are configured to increase the acceleration rate command value and the output command value simultaneously after the switching timing. [7] A control device for a gas turbine according to claim 1 or 2, wherein the acceleration rate setting unit is configured to start increasing the acceleration rate command value at a time point when the rotor speed increases by 300 rpm from a time point of the switching time point. [8] Control device for a gas turbine according to claim 1 or 2, wherein the fuel setpoint calculation unit is configured to calculate, as the fuel setpoint, a larger one of a first setpoint value, which is a constant value, and a second setpoint value calculated based on a deviation between an actual rotational speed and a target rotational speed of the rotor, during start-up of the gas turbine, and wherein the switching time is a time at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from the first setpoint to the second setpoint. [9] A control device for a gas turbine according to claim 8, wherein the fuel target value calculation unit is configured to calculate the rotor target speed based on the actual speed of the rotor and the acceleration rate target value. [10] The control device for the gas turbine according to claim 8, wherein the acceleration rate setting unit is configured to set a first acceleration rate as the acceleration rate target value at a first time point before the switching time point and is configured to set a third acceleration rate, which is greater than the first acceleration rate, as the acceleration rate target value at a second time point before the first time point during starting of the gas turbine. [11] Control device for controlling the operation of a gas turbine, comprising: a fuel setpoint calculation unit for calculating a fuel setpoint to be supplied to the gas turbine; and a motor output setting unit for setting an output setpoint of a starting motor of the gas turbine, wherein the engine output adjustment unit is configured to increase the output setpoint during start-up of the gas turbine and after a switching time at which the fuel setpoint calculated by the fuel setpoint calculation unit switches from a constant to a continuous increase. [12] Gas turbine plant, comprising: a gas turbine having a compressor for compressing air, a combustion chamber for generating a combustion gas by a combustion reaction between fuel and the compressed air from the compressor, and a turbine configured to be driven by the combustion gas from the combustion chamber; and the control device according to claim 1 or 11, configured to control the operation of the gas turbine. [13] A control method for controlling the operation of a gas turbine, comprising: a fuel setpoint calculation step of calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting step in which an acceleration rate setpoint of a rotor of the gas turbine is set, wherein the step of adjusting the acceleration rate comprises increasing the set value of the acceleration rate during start-up of the gas turbine and after a switching time at which the fuel setpoint calculated in the step of calculating the fuel setpoint switches from a constant to a continuous increase. [14] Control program for controlling the operation of a gas turbine, the control program is configured to cause a computer to execute: a fuel setpoint calculation process for calculating a fuel setpoint to be supplied to the gas turbine; and an acceleration rate setting process for setting an acceleration rate setpoint for a rotor of the gas turbine, the acceleration rate setting process comprising increasing the acceleration rate setpoint during start-up of the gas turbine and after a switching time at which the fuel setpoint calculated in the fuel setpoint calculation process changes from a constant to a continuous increase.

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