CONDITION DETECTION DEVICE, OPERATING TAX DEVICE, GAS TURBINE AND CONDITION DETECTION METHOD

Abstract

A state determination device (62) for determining the state of a gas turbine (1) connected to an electric generator (15), the gas turbine (1) comprising a compressor (11) for compressing input air into compressed air, a fuel supply device (14) for supplying fuel, a combustion chamber (12) for mixing the compressed air supplied by the compressor (11) and the fuel supplied by the fuel supply device (14) and combusting a resulting mixture to produce a combustion gas, and a turbine (13) for rotating with the produced combustion gas, wherein the state determination device (62) comprises: an instruction value acquisition unit (102) that detects a difference in a fuel flow instruction value of the fuel supplied by the fuel supply device (14) to the combustion chamber (12), an output detection unit (104) that detects a difference in an output of the electric generator (15), and a determination unit (106) that determines whether a rate of change of the fuel flow instruction value and a rate of change of the output satisfy or deviate from a predetermined relationship, based on the difference in the fuel flow instruction value and the difference in the output.

Description

[0001] The present invention relates to a state determination device, an operating control device, a gas turbine and a state determination method.

[0002] A gas turbine consists of a compressor, a combustion chamber, and a turbine. The gas turbine compresses air drawn in through an air intake using the compressor to produce compressed air at high temperature and pressure. Fuel is then fed into the compressed air through the combustion chamber to create a combustion gas (working fluid) at high temperature and pressure. This combustion gas drives the turbine. An electric generator is coupled to a rotating shaft of the gas turbine, and the gas turbine rotates the coupled electric generator to produce electricity. The combustion gas used to drive the turbine is discharged as exhaust gas from a discharge end of the turbine.

[0003] An operating control device that controls the gas turbine senses the states of the compressor, combustion chamber, and turbine and adjusts the amount of air to be supplied to the compressor and the amount of fuel to be supplied during operation, based on the sense results and an instruction value, in order to control the operation of the gas turbine. JP H04-81527A describes a gas turbine control device comprising a plurality of gas turbine inlet gas temperature detectors arranged in a ring-like manner on a high-temperature inlet section of a gas turbine to sense gas turbine inlet gas temperatures, a plurality of gas turbine exhaust gas temperature detectors arranged in a ring-like manner on a discharge section of the gas turbine to sense gas turbine exhaust gas temperatures, and a first determining unit.a second determination unit that determines whether a gas turbine inlet gas temperature deviation of the temperatures detected by the gas turbine inlet gas temperature detectors is equal to or greater than a permissible value; a second determination unit that estimates or calculates, for the one of the gas turbine inlet gas temperature detectors that has detected a largest or smallest temperature value, an estimated or calculated temperature of the relevant gas turbine inlet gas temperature detector based on temperatures of the gas turbine inlet gas temperature detectors that are adjacent to the relevant gas turbine inlet gas temperature detector, and that determines whether the estimated temperature and the detected temperature of the relevant gas turbine inlet gas temperature detector are equal to or greater than a predetermined value; and a sensor unit that recognizes the relevant gas turbine inlet gas temperature detector that has detected the largest or smallest value as a faulty detector.if both determination conditions of the first and second determination units are met or fulfilled, then it has.

[0004] US 6,230,479 B1 (D1) discloses a load control system for a power plant with a gas turbine. This system determines a fuel delivery instruction based on variations in generator output and shaft speed. To suppress instabilities and thermal stress, a fuel delivery instruction limiter is used. However, this limiter only restricts the rate of change of the command signal to dampen abrupt changes.

[0005] As described in JP H04-81527A, the gas turbine controls its operation using the sensing results from the respective components. In some cases, the gas turbine uses an output from an electric generator connected to the gas turbine as a parameter for controlling its operation, rather than using a mechanical output, which is difficult to sense. However, if operation is controlled using an output from the electric generator, the gas turbine may be unstable.

[0006] One object of the present invention is to provide a state determination device, an operating control device, a gas turbine and a state determination method for determining an operating state of a gas turbine in order to be able to operate the gas turbine more stably.

[0007] To solve the problem described above, a state determination device according to claim 1, an operating control device according to claim 3, a gas turbine according to claim 7, and a state determination method according to claim 8 are disclosed. The dependent claims relate to further advantageous embodiments of the invention. Fig. Figure 1 is a schematic diagram illustrating a gas turbine according to an embodiment of the present invention. Fig. Figure 2 is a schematic diagram illustrating an overall configuration of a state determination device. Fig. Figure 3 is a flowchart illustrating an example of a sequence control of the state determination device. Fig. Figure 4 is a schematic diagram illustrating an overall configuration of a turbine inlet temperature calculation unit. Fig. Figure 5 is a flowchart illustrating an example of a sequence control of the turbine inlet temperature calculation unit. Fig. Figure 6 is a flowchart illustrating an example of a sequence control of the turbine inlet temperature calculation unit. Fig. Figure 7 is a schematic diagram illustrating an overall configuration of another example of the turbine inlet temperature calculation unit.

[0008] Exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0009] Fig. Figure 1 is a schematic diagram illustrating a gas turbine according to an embodiment of the present invention. A gas turbine 1 according to the present embodiment has, as shown in Fig. Figure 1 illustrates a compressor 11, a combustion chamber 12, a turbine 13, a fuel supply device 14, a control device 16, and a rotor 18. The rotor 18 is positioned at central parts of the compressor 11, the combustion chamber 12, and the turbine 13 such that it passes through them. The compressor 11 and the turbine 13 of the gas turbine 1 are coupled by the rotor 18 so that they can rotate together. The gas turbine 1 is controlled by the control device (operating control device) 16. An electric generator 15 is coupled to the gas turbine 1. The electric generator 15 has a rotating part that is coupled to the generator 15 so that they can rotate together, and it rotates with the rotor 18 to generate electricity.

[0010] The compressor 11 compresses air A, which is drawn in through an air inlet, into compressed air A1. An inlet guide vane (IGV) 22, which regulates the amount of air A drawn in through the air inlet, is installed in the compressor 11. The amount of air A is regulated by adjusting the opening of the inlet guide vane 22. More precisely, the inlet guide vane 22 has a plurality of guide vane bodies 22a and an IGV activation unit 22b for changing the guide vane angle of the guide vane bodies 22a. The guide vane angle of the guide vane bodies 22a is adjusted by the IGV activation unit 22b to regulate the opening of the inlet guide vane 22 and thus regulates the amount of air A drawn in. If the opening of the inlet guide vane 22 is enlarged, the amount of air A entering the compressor is increased so that the pressure ratio of the compressor 11 is increased.On the other hand, if the opening of the inlet guide vane 22 is reduced, the amount of air A entering the air is reduced so that the pressure ratio of the compressor 11 is decreased.

[0011] Combustion chamber 12 supplies fuel F to the compressed air A1 compressed by compressor 11, mixes the compressed air A1 and the fuel F, and burns the resulting mixture to produce a combustion gas. The turbine 13 is rotated by the combustion gas produced by combustion chamber 12.

[0012] The rotor 18 is supported axially at both ends by bearings (not shown) and is designed to rotate about an axial center. A drive shaft of the electric generator 15 is coupled to one end of the rotor 18 on the side of the compressor 11 (the positioning is not specifically limited). The electric generator 15 is coaxial with the turbine 13 and can generate electricity by rotating the turbine 13.

[0013] Therefore, the air A drawn in through the air inlet of compressor 11 passes through the inner part of compressor 11 via the inlet guide vane 22 and is compressed into high-temperature, high-pressure air A1. Fuel F is supplied to the compressed air A1 from combustion chamber 12, and the compressed air A1 and fuel F are mixed and combusted to produce a high-temperature, high-pressure combustion gas. The high-temperature, high-pressure combustion gas produced by combustion chamber 12 passes through the inner part of turbine 13, thereby activating (rotating) turbine 13. This rotationally drives rotor 18, which in turn drives the electric generator 15 coupled to rotor 18. Consequently, the electric generator 15, coupled to rotor 18, is driven to generate electricity.Meanwhile, the combustion gas used to drive turbine 13 is released into the atmosphere as exhaust gas.

[0014] A casing pressure gauge 51, an inlet air condition detector 52, a blade path thermometer 53, and an exhaust gas thermometer 54 are provided in the gas turbine 1. The casing pressure gauge 51 is located on a line through which the compressed air A1 flows from the compressor 11 to the combustion chamber 12, more precisely on an inner part of the combustion chamber 12, and measures the pressure (the casing pressure) of the compressed air A1. The inlet air condition detector 52 has an inlet air thermometer 52A, which measures the inlet air temperature of the air A to be introduced into the compressor 11, and an inlet air pressure gauge 52B, which detects the inlet air pressure.The blade path thermometer 53 is located along the line through which the exhaust gas discharged from the turbine 13 flows and measures the temperature of the exhaust gas that has passed a blade of the last stage, which is located on the downstream side of the turbine 13 in the exhaust gas flow direction. The exhaust gas thermometer 54 is located on the downstream side of the blade path thermometer 53 and measures the temperature of the exhaust gas. The gas turbine 1 also acquires information about the output of the electric generator 15 to detect a load on the gas turbine 1. The output of the electric generator 15 can be measured by an output meter provided in the electric generator 15. Signals measured by the casing pressure gauge 51, the intake air condition detector 52, the blade path thermometer 53, and the exhaust gas thermometer 54 are fed to the control device 16.

[0015] The control device 16 controls parts such as the inlet guide vane 22 and a fuel control valve 35 on the basis of an instruction value corresponding to an output such as an output demand or a fuel flow instruction value, measurement results from measuring devices such as the casing pressure gauge 51, the intake air condition detector 52, the rotor blade path thermometer 53 and the exhaust gas thermometer 54, and / or a measurement result of the output of the electric generator 15 to control the operation of the gas turbine 1.

[0016] The control device 16 has a state determination device 62, a turbine inlet temperature calculation unit 64, and an operating control unit 66. In addition to the turbine inlet temperature calculation unit 64, the control device 16 includes other calculation units that estimate or calculate a state value based on the measurement results from the measuring devices, such as the casing pressure gauge 51, the intake air condition detector 52, the blade path thermometer 53, and the exhaust gas thermometer 54, as well as an instruction value.

[0017] Fig. Figure 2 is a schematic diagram illustrating the overall configuration of the state determination device. The state determination device 62 determines an operating state of the gas turbine. More precisely, the state determination device 62 determines whether a relationship between an instruction value at the fuel flow and an output of the electric generator 15 corresponds to or deviates from a predetermined relationship. The state determination device 62 has an instruction value acquisition unit 102, an output acquisition unit 104, and a determination unit 106.

[0018] The instruction value acquisition unit 102 processes a fuel flow instruction signal to detect changes in the fuel flow instruction signal. The fuel flow instruction signal is a signal that determines the flow rate of the fuel to be supplied to the combustion chamber 12. The instruction value acquisition unit 102 has a first-order delay filter 112 and a subtractor 114. The first-order delay filter 112 and the subtractor 114 are arranged in parallel, and the fuel flow instruction signal is input to them. The first-order delay filter (LAG) 112 outputs a fuel flow instruction signal that is the last signal before the current fuel flow instruction signal. The first-order delay filter 112 outputs the last fuel flow instruction signal to the subtractor 114.The subtractor 114 calculates a difference between the fuel flow instruction signal and the last fuel flow instruction signal output by the first-order delay filter 112. The subtractor 114 outputs the calculated difference in the fuel flow instruction signal to the determination unit 106.

[0019] Similarly, only one first-order delay filter 112 is arranged in the instruction value acquisition unit 102, but a plurality of first-order delay filters 112 can be placed so that they are connected in series. If the number of first-order delay filters 112 is increased, a fuel flow instruction signal to be subtracted can be a further preceding fuel flow instruction signal. Likewise, in the present embodiment, the instruction value acquisition unit 102 uses the fuel flow instruction signal; it is sufficient to use one instruction value at the output of the gas turbine 1, and an output request signal for the gas turbine 1 can be used instead of the fuel flow instruction signal.It is sufficient that the instruction value acquisition unit 102 can capture a rate of change (% / SEC) of the instruction value, and a target for which the difference is to be extracted, or a target for which the rate of change is to be extracted, is not specifically limited.

[0020] Output acquisition unit 104 processes an output from the electric generator (acquisition value of an output from the electric generator) to detect a change in the output of the electric generator. The output of the electric generator is a value of an electrical output from the electric generator 15. Output acquisition unit 104 has a first-order delay filter 122 and a subtractor 124. The first-order delay filter 122 and the subtractor 124 are arranged in parallel, and the output of the electric generator is fed into it. The first-order delay filter 122 (LAG) outputs the output of the electric generator that is the last output before the current output of the electric generator. That is, the first-order delay filter 122 outputs the last output of the electric generator before the subtractor 124.Subtractor 124 calculates the difference between the output of the electric generator and the last output of the electric generator as output by the first-order delay filter 122. Subtractor 124 outputs the calculated difference in the output of the electric generator to the target unit 106. It is sufficient that the output detection unit 104 can detect a rate of change (% / sec) of the output, and there is no specific limit to the target for which the difference is to be extracted or the target for which the rate of change is to be extracted.

[0021] The determination unit 106 determines, based on a difference x1 detected by the instruction value acquisition unit 102 and a difference x2 detected by the output acquisition unit 104, whether the operating state of the gas turbine 1 corresponds to a predetermined relationship, more precisely, whether the relationship between the instruction value at the fuel flow and the output of the electric generator 15 corresponds to or deviates from a predetermined relationship. The predetermined relationship is one in which the fuel flow and the output can be considered proportional to each other. The determination unit 106 has a comparison unit 132 and a signal output unit 136. The comparison unit 132 compares the difference x1 detected by the instruction value acquisition unit 102 with the difference x2 detected by the output acquisition unit 104.In the present embodiment, the comparator 132 multiplies the difference x2 by a factor “a” to match the scales of the difference x1 and the signal, and then detects a difference between them to determine whether the difference is greater than a limit ε. More precisely, the comparator 132 checks whether |x1-a*x2|>ε. The comparator 132 determines that the relationship between the instruction value at the fuel flow and the output of the electric generator 15 deviates from the predetermined relationship if |x1-a*x2|>ε, and determines that the relationship between the instruction value at the fuel flow and the output of the electric generator 15 satisfies the predetermined relationship if |x1-a*x2|≤ε.

[0022] The signal output unit 136 outputs a signal based on a result from the comparator unit 132. The signal output unit 136 outputs a signal indicating a state that deviates from the relationship when the comparator unit 132 has determined that the operating state deviates from the relationship, and outputs a signal indicating that the relationship is satisfied when the comparator unit 132 has determined that the operating state satisfies the relationship.

[0023] The sequence of a sequence control of the state determination device 62 is described below with reference to Fig. 3 described. Fig. Figure 3 is a flowchart illustrating an example of the sequence control of the state-determining device. The state-determining device 62 detects a difference in the fuel flow instruction value with the instruction value acquisition unit 102 (step S12) and detects a difference in the output of the electric generator 15 with the output acquisition unit 104 (step S14). The processes at steps S12 and S14 can be performed in parallel or in reverse order. The state-determining device 62 detects a difference in the fuel flow instruction value and a difference in the output of the same time priority.

[0024] Upon detecting the differences, the state determination device 62 determines whether | (difference in fuel flow instruction value) - (difference in electric generator output) |>ε, that is, |x1-a*x2|>ε, using the comparison unit 132 (step S16). If the state determination device 62 has determined that | (difference in fuel flow instruction value) - (difference in electric generator output) |>ε (Yes at step S16), the signal output unit 136 outputs a signal indicating that the operating state deviates from the relationship (step S18). If the state determination device 62 has determined that the | (Difference in fuel flow instruction value) - (Difference in electric generator output) |≤ε (No at step S16), the signal output unit 136 outputs a signal indicating that the operating state corresponds to the relationship (step S20).

[0025] It is sufficient for the state determination device 62 to output only one of the signals indicating that the state deviates from the relationship, or the signal indicating that the state conforms to the relationship, without outputting both. In this case, if the signal is not output, the state can be considered to be the other state than the one indicated by the signal.

[0026] Fig. Figure 4 is a schematic diagram illustrating the overall configuration of the turbine inlet temperature calculation unit. The turbine inlet temperature calculation unit 64 calculates or estimates a turbine inlet temperature that is difficult to measure. The turbine inlet temperature calculation unit 64 calculates a turbine inlet temperature value based on the output (GT - output of the electric generator) detected by the electric generator 15, an IGV signal indicating the opening of the inlet guide vane 22 detected by the IGV activation unit 22b, the compressor inlet temperature detected by the inlet air thermometer 52A, and the compressor inlet pressure detected by the inlet air pressure gauge 52b.

[0027] The turbine inlet temperature calculation unit 64 has a turbine inlet temperature processing unit 140, a turbine inlet temperature correspondence signal output unit 142, a filter 144, a signal switch 146, a signal generator 148 and a signal generator 149.

[0028] The output (the gas turbine (GT) output of the electric generator) detected by the electric generator 15, the IGV signal indicating the opening of the inlet guide vane 22 detected by the IGV activation unit 22b, the compressor inlet temperature detected by the inlet air thermometer 52A, and the compressor inlet pressure detected by the inlet air pressure gauge 52B are input to the gas turbine temperature processing unit 140. The turbine inlet temperature processing unit 140 performs processing based on the input values ​​to calculate an estimated or calculated value of the turbine inlet temperature.

[0029] The turbine inlet temperature correspondence signal output unit 142 outputs a signal corresponding to the turbine inlet temperature calculated by the turbine inlet temperature processing unit 140 to the respective parts that perform the control using the turbine inlet temperature.

[0030] Filter 144 is arranged on a channel through which the GT output of the electric generator is fed to the turbine inlet temperature processing unit 140. Filter 144 is a time constant filter that can delay fluctuations in the signal acquired by the electric generator 15 and fed to the turbine inlet temperature processing unit 140 by changing the time constant. Filter 144 switches the filter time constant based on a signal input via the signal switch 146.

[0031] The signal switch 146 is connected to the signal generators 148 and 149 and switches based on the signal input from the state determination device 62, depending on whether the signal generated by signal generator 148 is input to filter 144, or whether the signal generated by signal generator 149 is input to filter 144. Signal generators 148 and 149 each generate different signals. When the signal indicating that the state corresponds to the relationship is received, the signal switch 146 outputs the signal from signal generator 148 to filter 144. When the signal indicating that the state deviates from the relationship is received, the signal switch 146 outputs the signal from signal generator 149 to filter 144.The filter 144 applies a first time constant (a time constant with normal times) when the signal is input from the signal generator 148, and applies a second time constant, which has a value greater than the first time constant, when the signal is input from the signal generator 149.

[0032] Fig. Figure 5 is a flowchart illustrating an example of a sequence control of the turbine inlet temperature calculation unit. Fig. Figure 5 illustrates a filter selection process. The turbine inlet temperature calculation unit 64 determines whether the state determination device 62 has determined that the state deviates from the relationship (step S30). If the state determination device 62 has determined that the state does not deviate from the relationship (No at step S30), the turbine inlet temperature calculation unit 64 uses the time constant with normal times (step S32). If the state determination device 62 has determined that the state deviates from the relationship (Yes at step S30), the turbine inlet temperature calculation unit 64 uses the time constant, which has a larger value than the normal times (step S34).

[0033] The turbine inlet temperature calculation unit 64 switches between the time constants of the filter 144 based on the result of the state determination device 62 in the manner described above, thereby causing a value with smaller fluctuation than the value of the output detected by the electric generator 15, which is to be input to the turbine inlet temperature processing unit 140, in the state which deviates from the relationship.

[0034] The operating control unit 66 controls the operation of the respective parts in the gas turbine 1 based on information output from the state determination device 62 and the turbine inlet temperature calculation unit 64, the measurement results from the various measuring devices, and the instruction value. For example, the operating control unit 66 performs an IGV control to adjust the IGV activation unit 22b, which activates the inlet guide vane 22, to the quantity of air (the air input quantity) to be introduced into the compressor 11. The operating control unit 66 controls the IGV activation unit 22b to change the opening (hereinafter the "IGV opening") of the inlet guide vane 22 to adjust the quantity of air A to be introduced into the compressor 11. More precisely, the operating control unit 66 controls the IGV opening so that it is closed during full-load operation.The nominal opening is the opening at a time when the gas turbine output becomes a nominal output. The operating control unit 66 also performs fuel control to control the fuel adjusting valve 35, which is provided on a fuel supply line 34 for supplying fuel F to the combustion chamber 12, in order to adjust the supply quantity of fuel F. The operating control unit 66 controls the fuel adjusting valve 35 to adjust the amount of fuel F to be supplied (injected) to the compressed air A1.

[0035] As described above, in the present embodiment, the state-determining device 62 can determine whether the gas turbine 1 is operating in a state that corresponds to or deviates from the predetermined relationship. That is, the state-determining device 62 can determine whether the output of the electric generator 15 is affected or influenced by the number of rotations of a system connected to the electric generator 15 by performing a comparison of the difference between the rate of change (% / sec) of the GT output of the electric generator and the rate of change (% / sec) of the fuel flow instruction (CSO) signal, which is an example of the rate of change of the mechanical output of the gas turbine 1.This means that, based on a positive proportional relationship maintained between the rate of change of the fuel flow instruction value and the rate of change of the GT output of the electric generator, it is possible to detect whether the GT output of the electric generator fluctuates due to a change in the number of system rotations, depending on whether the rate of change of the fuel flow instruction value and the rate of change of the GT output of the electric generator deviate from this positive proportional relationship. This allows the state-determining device 62 to suitably detect whether the electric generator 15 is affected by the number of rotations of the connected system. It is preferable for the state-determining device 62 to detect a calorie or a heat unit of the fuel and perform a correction based on the heat unit when the fuel flow is used.

[0036] The control device 16 of the present embodiment can operate the gas turbine stably by adjusting the gas turbine output of the electric generator, which is to be input to the turbine inlet temperature calculation unit 64 on the basis of the result of the state determination device 62, more precisely by adjusting the gas turbine output of the electric generator to a value with smaller fluctuation than the current value when the state deviates from the relationship.

[0037] In the embodiment described above, the time constant is set such that it adjusts the gas turbine output of the electric generator to a value with less fluctuation than the current value when the state-determining device 62 has determined that the state deviates from the relationship. However, the adjustment is not limited to this, and it is sufficient that the fluctuation in the gas turbine output of the electric generator can be reduced. For example, if the state-determining device 62 has determined that the state deviates from the relationship, a value can be set as the gas turbine output of the electric generator at a time when the state is determined to conform to the relationship (a value immediately before leaving, a final value).

[0038] The turbine inlet temperature calculation unit 64 can switch between using and not using the result of the state determination device 62 depending on the state of the gas turbine. Fig. Figure 6 is a flowchart illustrating an example of the sequence control of the turbine inlet temperature calculation unit. The turbine inlet temperature calculation unit 64 determines whether the gas turbine 1 is in a stable operating state (step S40). The stable operating state is a state in which the gas turbine 1 operates under a rated condition or in a state that maintains a predetermined output for a time equal to or longer than a predetermined period. If the turbine inlet temperature calculation unit 64 has determined that the turbine 1 is operating in the stable operating state (Yes at step S40), a control is executed based on the result of the state determination device 62 (step S42). That is, the sequences in Fig. The five steps described above are executed. If the turbine inlet temperature calculation unit 64 has determined that the gas turbine 1 is not in a stable operating state (No at step S40), a control operation is executed without using the result of the state determination device 62 (step S44).

[0039] If the gas turbine 1 is not in a stable operating state, the turbine inlet temperature calculation unit 64 does not use the result of the state determination device 62, thus enabling highly responsive control in an operation such as during start-up or while the output fluctuates based on an instruction value.

[0040] While the GT output of the electric generator is set based on the result of the state-determining device 62 in the present embodiment, the present embodiment is not limited to this. The turbine inlet calculation unit 64 can set the calculated value of the turbine inlet temperature based on the GT output of the electric generator, i.e., in the present embodiment, based on the result of the state-determining device 62.

[0041] Fig. Figure 7 is a schematic diagram illustrating an overall configuration of another example of the turbine inlet temperature calculation unit. A turbine inlet temperature calculation unit 64a, which is in Fig.Figure 7 illustrates the turbine inlet temperature processing unit 140, the turbine inlet temperature correspondence signal output unit 142, the filter 144, a filter 150, a signal switch 152, a signal generator 156 and a signal generator 154.

[0042] The output (the gas turbine (GT) output of the electric generator) detected by the electric generator 15, the IGV signal indicating the opening of the inlet guide vane 22 detected by the IGV activation unit 22b, the compressor inlet temperature detected by the inlet air thermometer 52A, and the compressor inlet pressure detected by the inlet air pressure gauge 52b are input to the turbine inlet temperature processing unit 140. The turbine inlet temperature processing unit 140 performs processing based on the input values ​​to calculate the calculated value of the turbine inlet temperature.

[0043] The turbine inlet temperature correspondence signal output unit 142 outputs a signal corresponding to the turbine inlet temperature calculated by the turbine inlet temperature processing unit 140 to respective parts that perform control using the turbine inlet temperature.

[0044] Filter 144 is arranged on a channel through which the GT output of the electric generator is fed to the turbine inlet temperature processing unit 140. Filter 144 is a filter with an adjustable time constant, which introduces a delay in the fluctuation of the signal acquired by the electric generator 15 and fed to the turbine inlet temperature processing unit 140. It is not necessary to introduce a delay by adjusting the time constant of filter 144.

[0045] Filter 150 is located between the turbine inlet temperature processing unit 140 and the turbine inlet temperature correspondence signal output unit 142. Filter 150 is a filter that can modify the time constant by changing its value and can introduce a delay in the fluctuation of a signal input from the turbine inlet temperature processing unit 140 to the turbine inlet temperature correspondence signal output unit 142. Filter 150 switches its time constant based on a signal input via the signal switch 152.

[0046] The signal switch 152 is connected to the signal generators 156 and 154 and switches, depending on the signal input from the state determination device 62, whether a signal generated by signal generator 156 is input to filter 150, or a signal generated by signal generator 154 is input to filter 150. Signal generators 156 and 154 each generate different signals. If a signal indicating that the state corresponds to the relationship is received, the signal switch 152 outputs the signal from signal generator 156 to filter 150. If a signal indicating that the state deviates from the relationship is received, the signal switch 152 outputs the signal from signal generator 154 to filter 150.Filter 150 applies a first time constant (a time constant with normal timing) when the signal from signal generator 156 is input, and applies a second time constant, which has a larger value than the first time constant, when the signal from signal generator 154 is input. The first time constant can be one that allows a signal to pass through unchanged.

[0047] The turbine inlet temperature calculation unit 64a adjusts the calculation result of the turbine inlet temperature calculation unit 140, instead of adjusting the gas turbine output of the electric generator, based on the result of the state determination device 62, in order to reduce fluctuations in the calculated value when the state deviates from the relationship and to stabilize the operation of the gas turbine. In this way, identical effects can be achieved as by reducing the fluctuation in the value calculated based on the gas turbine output of the electric generator.

[0048] In the embodiment described above, a case was described where a device using a gas turbine output of the electric generator is described, specifically the turbine inlet temperature calculation unit 64. However, identical effects with other devices using the gas turbine output of the electric generator can be achieved by similarly performing a correction to reduce a fluctuation in the gas turbine output of the electric generator, or by correcting to reduce a fluctuation in a value calculated using the gas turbine output of the electric generator based on the result of the state determination device 62 when the state deviates from the relationship. Reference symbol list 1 gas turbine 11 Compressor 12 Combustion chamber 13 Turbine 14 Fuel supply device 15 electric generator 16 Control device (operating control device) 18 Rotor 22 Inlet guide scoop 22a Guide vane body 22b IGV Activation Unit 34 Fuel supply line 35 Fuel control valve 51 Housing pressure gauge 52 Air condition detector 52A Air Entry Thermometer 52B Air pressure gauge 53 shovel path thermometers 54 Fuel gas thermometers 62 Condition determination device 64, 64a Turbine inlet temperature calculation unit 66 Operating control unit 102 Instruction value acquisition unit 104 Output recording unit 106 Unit of determination 112 First-order delay value 114 Subtractors 122 First-order delay value 124 subtractors 132 comparison unit 136 Signal output unit 140 Turbine inlet temperature processing unit 142 Turbine inlet temperature correspondence signal output unit 144 filters 146 Signal switches 148 signal generators 149 signal generators 150 filters 152 Signal switches 154 signal generators 156 signal generators

Claims

[1] A state determination device (62) for determining the state of a gas turbine (1) connected to an electric generator (15), the gas turbine (1) comprising a compressor (11) for compressing input air into compressed air, a fuel supply device (14) for supplying fuel, a combustion chamber (12) for mixing the compressed air supplied by the compressor (11) and the fuel supplied by the fuel supply device (14) and burning a resulting mixture to produce a combustion gas, and a turbine (13) for rotating with the produced combustion gas, wherein the state determination device (62) comprises: an instruction value acquisition unit (102) that detects a difference in a fuel flow instruction value of the fuel supplied by the fuel supply device (14) to the combustion chamber (12), an output detection unit (104) that detects a difference in an output of the electric generator (15), and a determination unit (106) that determines whether a rate of change of the fuel flow instruction value and a rate of change of the output satisfy or deviate from a predetermined relationship, based on the difference in the fuel flow instruction value and the difference in the output. [2] The state determination device (62) according to claim 1, wherein The instruction value acquisition unit (102) detects a difference between a detected fuel flow instruction value and a fuel flow instruction value that was last detected, and The output recording unit (104) records a difference between a recorded output and an output that was last recorded. [3] An operating control device (16) comprising: the state determination device (62) according to claim 1 or 2, and a control device (16) that controls the gas turbine (1) on the basis of the fuel flow instruction value and the output of the electric generator (15). [4] The operating control device (16) according to claim 3, wherein the control device (16) changes a value of the detected output of the electric generator (15) to a value with a lower fluctuation when the state determination device (62) has determined that an operation of the gas turbine (1) deviates from a predetermined relationship. [5] The operating control device (16) according to claim 4, wherein the control device (16) uses a final value as a value of the output of the electric generator (15) when the state determination device (62) has determined that an operation of the gas turbine (1) deviates from a predetermined relationship. [6] The operating control device (16) according to claim 3, wherein the control device (16) changes a calculated value to a value with a lower fluctuation on a basis of a value of the output of the electric generator (15) when the state determination device (62) has determined that an operation of the gas turbine (1) deviates from a predetermined relationship. [7] A gas turbine (1) comprising: a compressor (11) that compresses input air into compressed air, a fuel supply device (14) that supplies a fuel, a combustion chamber (12) which mixes the compressed air supplied by the compressor (11) and the fuel supplied by the fuel supply device (14) and burns a resulting mixture to produce combustion gas, a turbine (13) which is rotated with the generated combustion gas, and the operating control device (16) according to one of claims 3 to 6. [8] A state determination procedure for determining a state of a gas turbine (1) connected to an electric generator (15), the gas turbine (1) comprising a compressor (11) that compresses input air into compressed air, a fuel supply device (14) that supplies fuel, a combustion chamber (12) that mixes the compressed air supplied by the compressor (11) and the fuel supplied by the fuel supply device (14) and combusts a resulting mixture to produce combustion gas, and a turbine (13) that rotates with the combustion gas, the state determination procedure comprising the following steps: Detecting a difference in a fuel flow instruction value of the fuel supplied by the fuel supply device (14) to the combustion chamber (12), Detecting a difference in an output of the electric generator (15), and Determine whether a rate of change of the fuel flow instruction value and a rate of change of the output satisfy or deviate from a predetermined relationship, based on the difference in the fuel flow instruction value and the difference in the output.

Images