JP5762874B2 - Gas turbine combustor, gas turbine, and control method of gas turbine combustor - Google Patents

Description

  The present invention relates to a gas turbine combustor, a gas turbine, and a gas turbine combustor control method.

  A gas turbine power plant supplies fuel and compressed air to a combustor, burns the fuel to generate combustion gas, rotationally drives the turbine with this combustion gas, and guides the driving force of this turbine to the generator to generate electric power. Occur.

  By the way, the combustion gas for rotationally driving the turbine has a higher nitrogen oxide (NOx) concentration as the combustion temperature becomes higher. Therefore, a gas turbine combustor that uses a premixed combustion method that suppresses the local increase in the combustion temperature by burning the premixed gas to generate combustion gas and suppresses the generation of nitrogen oxides (NOx) is known. It has been.

  However, since the combustion of the lean premixed gas is unstable, the fuel is stabilized by controlling the heat generation and temperature distribution in the combustor by supplying fuel from multiple independent fuel systems to multiple fuel nozzles. . Since the fuel distribution condition for stabilizing the flame differs depending on the combustion temperature, the combustion temperature is calculated from the gas turbine state quantity, and the fuel distribution schedule control is performed.

JP-A-6-101808 Japanese Patent Laid-Open No. 11-82067 JP 2010-156308 A Japanese Patent Laid-Open No. 2003-328779 JP 2004-2111625 A

  In the realization of a low NOx combustor, the temperature distribution in the combustor is appropriately controlled by a plurality of fuel systems to stabilize the lean mixed combustion, but the air mixed in the combustion is the state of the outside air to be taken in (temperature and humidity) , These seasonal variations), the temperature, pressure and density change due to the reduced efficiency of the compressor. This change in the state quantity of air changes (increases or decreases) the amount of fuel burned per unit volume (ie, combustion load factor) in the gas turbine combustor even under the same combustion temperature, and changes the flame shape. May make combustion unstable. Flame instability increases pressure fluctuations in the combustor and can cause combustor damage or misfire, so corrections to the fuel distribution control described above are required to stabilize the flame.

  By the way, the calculation method of the combustion temperature is, for example, a method of calculating from the turbine efficiency calculated from the air flow rate sucked by the compressor, the discharge pressure or pressure ratio of the compressor and the exhaust gas temperature of the turbine, or the fuel-air ratio in the gas turbine combustor. And a method of calculating from the composition of the combustion gas. In any of the methods, the combustion load in the gas turbine combustor cannot be expressed, and the change in the combustion load factor with the change in the state quantity of air cannot be handled.

  In other words, the conventional gas turbine combustor which calculates the combustion temperature and stabilizes the combustion of the lean premixed gas cannot represent the combustion load in the gas turbine combustor, and is accompanied by a change in the air state quantity. Cannot cope with changes in combustion load factor.

  Accordingly, the present invention provides a gas turbine combustor, a gas turbine, and a gas turbine combustion capable of stabilizing combustion in response to a change in the combustion load factor in the gas turbine combustor and suppressing generation of nitrogen oxides (NOx). We propose a method for controlling the container.

In order to solve the above-described problem, a gas turbine combustor according to an embodiment of the present invention mixes a plurality of fuel valves capable of adjusting the flow rate of fuel, and the fuel and air flowing from the fuel valve to premix the mixture. A plurality of premixed combustion burners having a premixing chamber, a hollow cylinder having a combustion chamber for generating a combustion gas by burning the premixed gas taken from the premixed combustion burner, and calculating a combustion temperature of the combustion gas The fuel distribution amount reference value for each premixing chamber corresponding to the value and the distribution amount correction value corresponding to the state amount of the air flowing into the premixing chamber are stored in advance, and the combustion gas is calculated from the state amount of the gas turbine. The combustion temperature is calculated and the state quantity of the air flowing into the premixing chamber is measured, and the distribution quantity reference value is corrected with the distribution quantity correction value from the calculation result and the measurement result, and the fuel valve is measured for each fuel valve. fuel And a control unit for controlling the distribution amount, predetermined replacement air flow rate correction value corresponding to the state quantity of the air flowing into the replacement air flow and the premixing chamber corresponding to the combustion temperature calculation value of the combustion gas, wherein When the fuel distribution is stopped in any of the premixing chambers, the fuel distribution is performed by correcting the replacement air flow rate with the replacement air flow rate correction value from the calculation result of the combustion temperature and the measurement result of the state quantity. The flow rate of the air replacing the premixing chamber to be stopped is controlled .

  Moreover, the gas turbine which concerns on embodiment of this invention is equipped with the said gas turbine combustor, It is characterized by the above-mentioned.

Furthermore, a control method for a gas turbine combustor according to an embodiment of the present invention includes a plurality of fuel valves capable of adjusting the flow rate of fuel, and the fuel and air that are connected to the fuel valves to form an air-fuel mixture. A control method for a gas turbine combustor comprising: a plurality of premixers having a premixing chamber; and a hollow cylinder having a combustion chamber connected to the premixer to convert the mixture into a combustion gas, A fuel distribution amount reference value for each premixing chamber corresponding to the combustion temperature calculation value of the combustion gas and a distribution amount correction value corresponding to a state amount of air flowing into the premixing chamber are determined in advance, and the state of the gas turbine The combustion temperature of the combustion gas is calculated from the quantity, the state quantity of the air flowing into the premixing chamber is measured, and the distribution quantity reference value is calculated from the calculation result of the combustion temperature and the measurement result of the state quantity. The premixing chamber is corrected with a correction value. The controls the distribution amount of the fuel, the set of replacement air flow rate correction value corresponding to the state quantity of the air flowing into the replacement air flow and the premixing chamber corresponding to the combustion temperature calculation value of the combustion gas in advance, the premixing When stopping the fuel distribution in any of the chambers, the fuel distribution is stopped by correcting the replacement air flow rate with the replacement air flow rate correction value from the calculation result of the combustion temperature and the measurement result of the state quantity. The flow rate of the air replacing the premixing chamber is controlled .

  According to the present invention, a gas turbine combustor, a gas turbine, and a gas turbine combustion capable of stabilizing combustion in response to a change in a combustion load factor in the gas turbine combustor and suppressing generation of nitrogen oxides (NOx). Can propose a method of controlling the container.

1 is a schematic system configuration diagram showing an example of a gas turbine power plant to which a gas turbine combustor according to a first embodiment of the present invention is applied. 1 is a schematic system configuration diagram showing a gas turbine combustor according to a first embodiment of the present invention. The schematic system block diagram which shows the other example of the gas turbine combustor which concerns on 1st Embodiment of this invention. The control block diagram of the gas turbine power plant to which the gas turbine combustor which concerns on 1st Embodiment of this invention is applied. The figure which shows an example of the distribution function of the gas turbine combustor which concerns on 1st Embodiment of this invention. The figure which shows an example of the correction function of the gas turbine combustor which concerns on 1st Embodiment of this invention. The figure which shows an example of the correction function of the gas turbine combustor which concerns on 1st Embodiment of this invention. The figure which shows an example of the correction function of the gas turbine combustor which concerns on 1st Embodiment of this invention. The schematic system block diagram which shows the gas turbine combustor which concerns on 2nd Embodiment of this invention. The schematic system block diagram which shows the other example of the gas turbine combustor which concerns on 2nd Embodiment of this invention. The control block diagram of the gas turbine power plant to which the gas turbine combustor which concerns on 2nd Embodiment of this invention is applied. The figure which shows an example of the distribution function of the gas turbine combustor which concerns on 2nd Embodiment of this invention. The figure which shows an example of the replacement air supply function of the gas turbine combustor which concerns on 2nd Embodiment of this invention. The figure which shows an example of the replacement air flow rate correction function of the gas turbine combustor which concerns on 2nd Embodiment of this invention. The figure which shows an example of the replacement air flow rate correction function of the gas turbine combustor which concerns on 2nd Embodiment of this invention. The figure which shows an example of the replacement air flow rate correction function of the gas turbine combustor which concerns on 2nd Embodiment of this invention.

  Embodiments of a gas turbine combustor, a gas turbine, and a gas turbine combustor control method according to the present invention will be described with reference to the drawings.

[First Embodiment]
1st Embodiment of the control method of the gas turbine combustor which concerns on this invention, a gas turbine, and a gas turbine combustor is described with reference to FIGS.

  FIG. 1 is a schematic system configuration diagram showing an example of a gas turbine power plant to which the gas turbine combustor according to the first embodiment of the present invention is applied.

  As shown in FIG. 1, a gas turbine power plant 1 according to this embodiment includes a compressor 3 that takes in air from the atmosphere via inlet guide vanes 2 and compresses it into high-temperature and high-pressure combustion air, and an air flow path 5. A gas turbine combustor 6 that takes in combustion air through the gas and burns fuel, a gas turbine 7 that introduces combustion gas from the gas turbine combustor 6 and that is driven to rotate by adiabatic expansion of the combustion gas, and a gas turbine 7. And a generator 8 that drives to obtain an output. The compressor 3 and the gas turbine 7 are rotationally integrated via a turbine shaft 9.

  The gas turbine power plant 1 also includes a plurality of fuel control valves 11a, 11b, and 11c (fuel valves) that can adjust the flow rate of fuel supplied to the gas turbine combustor 6. The gas turbine power plant 1 drives the compressor 3 to send compressed air to the gas turbine combustor 6, while appropriately opening the fuel control valves 11a, 11b, and 11c to send fuel to the gas turbine combustor 6. A high-temperature and high-pressure combustion gas is generated in the gas turbine combustor 6, and the gas turbine 7 is rotationally driven by this combustion gas to obtain an output from the generator 8.

  Furthermore, the gas turbine power plant 1 includes a fuel control device 12 (control unit) that controls the fuel distribution amount for each of the fuel control valves 11a, 11b, and 11c.

  The fuel control device 12 is an arithmetic device such as a computer having a storage unit. The fuel control device 12 includes a gas turbine speed N obtained from a speed detector 15 close to the shaft end gear 13, a compressor inlet air pressure PX1 obtained from an inlet air pressure detector 21 at the inlet of the compressor 3, and the compressor 3. Compressor inlet air absolute humidity HX1 obtained from the inlet air humidity detector 24 at the inlet of the compressor, compressor discharge air pressure PX2 obtained from the compressor discharge air pressure detector 22 at the outlet of the compressor 3, outlet of the compressor 3 The compressor discharge air temperature TX1 obtained from the compressor discharge air temperature detector 23, the exhaust gas temperature TX2 obtained from the exhaust gas temperature detector 25 at the turbine outlet, the generator output MW obtained from the generator output detector 26, and the inlet guide vane The opening degree IGV and the like of 2 are collected as gas turbine operating state quantities.

  Further, the fuel control device 12 performs a predetermined calculation based on various quantities of the gas turbine operating state, outputs fuel distribution control signals FREF1, FREF2, and FREF3 to the fuel control valves 11a, 11b, and 11c, respectively, and the fuel control valve The valve opening degree of 11a, 11b, 11c is controlled, and the distribution amount of the fuel of each valve 11a, 11b, 11c is controlled.

  FIG. 2 is a schematic system configuration diagram showing the gas turbine combustor according to the first embodiment of the present invention.

  As shown in FIG. 2, the gas turbine combustor 6 according to the present embodiment mixes fuel A and air A that flow from the fuel control valves 11 a, 11 b, and 11 c through the fuel nozzles 29 a, 29 b, and 29 c and premixes them. Combustion that generates combustion gas by burning a plurality of premixed combustion burners 32a, 32b, and 32c having premixing chambers 31a, 31b, and 31c to be worried and premixed gas taken from the premixed combustion burners 32a, 32b, and 32c A hollow body 35 having a chamber 33 and a transition piece 36 connected to the combustion chamber 33 and sending combustion gas to the gas turbine 7 are provided.

  The premixed combustion burners 32a, 32b, and 32c are all at one end of a cylindrical hollow body 35. The premixed combustion burners 32a, 32b, and 32c mix the combustion flowing from the fuel control valves 11a, 11b, and 11c together with the high-pressure air that is taken from the compressor 3 in the premixing chambers 31a, 31b, and 31c, so that the fuel is in a lean state. Gas is generated and sent to the combustion chamber 33. One of the premixed combustion burners 32a, 32b, 32c (for example, the premixed combustion burner 32a) generates a premixed gas with a slightly higher fuel-air ratio than the other burners (for example, the premixed combustion burner 32b, 32c). In addition, while functioning as flame holding f (fire type) of the other burners (premixed combustion burners 32b, 32c), a diffusion combustion nozzle (not shown) is provided to stabilize the start-up.

  The gas turbine combustor 6 stabilizes the combustion in the combustion chamber 33 at a relatively low temperature by a burner (premixed combustion burner 32a) for flame holding f (fire type), and a combustion gas G having a low nitrogen oxide (NOx) concentration. Is generated.

  FIG. 3 is a schematic system configuration diagram showing another example of the gas turbine combustor according to the first embodiment of the present invention.

  As shown in FIG. 3, the gas turbine combustor 6A according to this embodiment includes a diffusion combustion burner 38 that diffuses and burns fuel that flows from the fuel control valve 11a through the fuel nozzle 29a in the combustion chamber 33, and a fuel control. A plurality of premixed combustion burners 32b and 32c having premixing chambers 31b and 31c for mixing the fuel flowing from the valves 11b and 11c through the fuel nozzles 29b and 29c and the air A to make a premixed gas; and premixed combustion A hollow body 35 having a combustion chamber 33 for combusting premixed gas taken in from the burners 32b and 32c to generate combustion gas; and a transition piece 36 for connecting the combustion chamber 33 and feeding the combustion gas to the gas turbine 7. .

  The diffusion combustion burner 38 is at one end of the cylindrical hollow body 35. The diffusion combustion burner 38 sends fuel and compressed air into the combustion chamber 33 at a higher fuel / air ratio than the premixed combustion burners 32b and 32c, and functions as a flame holding (fire type) f for the premixed combustion burners 32b and 32c. .

  The premixed combustion burners 32 b and 32 c are located on the side surface of the cylindrical hollow cylinder 35 and in the vicinity of one end of the hollow cylinder 35. The premixed combustion burners 32b and 32c mix the combustion flowing from the fuel control valves 11b and 11c together with the high-pressure air taken from the compressor 3 in the premixing chambers 31b and 31c, thereby generating a premixed gas in a lean fuel state. Premixed gas is fed from the side surface of the cylinder 35 toward the center line of the combustion chamber 33.

  The gas turbine combustor 6A uses the diffusion combustion burner 38 to start the gas turbine 7. When the operation load of the gas turbine 7 reaches a predetermined load, the flow rate of the fuel to the diffusion combustion burner 38 is reduced and premixed instead. The combustion in the combustion chamber 33 is stabilized at a relatively low temperature using the combustion burners 32b and 32c, and a combustion gas G having a low nitrogen oxide (NOx) concentration is generated.

  Next, the fuel control device 12 that controls the fuel distribution amount of the gas turbine combustor 6 will be described.

  FIG. 4 is a control block diagram of a gas turbine power plant to which the gas turbine combustor according to the first embodiment of the present invention is applied.

  As shown in FIG. 4, the fuel control device 12 according to the present embodiment includes the fuel distribution amount reference value and the premixing chamber 31a for each of the premixing chambers 31a, 31b, 31c corresponding to the combustion temperature calculation value of the combustion gas G. , 31b, 31c, the distribution amount correction value corresponding to the state quantity of the air flowing into the cylinder 31b is stored in advance, the combustion temperature of the combustion gas G is calculated from the gas turbine operation state quantities (state quantities of the gas turbine 7), and premixed. The amount of state of the air flowing into the chambers 31a, 31b, 31c is measured, and the distribution amount reference value is corrected with the distribution amount correction value from the calculation result and the measurement result, and the fuel of each premixed combustion burner 32a, 32b, 32c is corrected. Control the amount of distribution. The fuel control device 12 includes a total fuel flow rate calculation unit 41, a combustor temperature calculation unit 42, a storage unit 43, and a distribution control unit 45.

  The total fuel flow rate calculation unit 41 acquires various amounts of gas turbine operation state (specifically, gas turbine speed N, compressor inlet air pressure PX1, compressor discharge air pressure PX2, exhaust gas temperature TX2, and generator output MW). Then, the total flow rate of the fuel is calculated on the basis of the gas turbine operating state quantities and a predetermined arithmetic expression, and the total fuel flow rate control signal FREF is output.

  The combustor temperature calculation unit 42 acquires various amounts of gas turbine operation state (specifically, compressor inlet air pressure PX1, compressor discharge air pressure PX2, exhaust gas temperature TX2, opening IGV of the inlet guide vane 2). The combustion temperature of the combustion gas G in the combustion chamber 33 is calculated on the basis of the gas turbine operating state quantities and a predetermined arithmetic expression, and the combustor control temperature TITREF is output.

  The storage unit 43 indicates the fuel distribution amount reference value (ratio) for each of the premixed combustion burners 32a, 32b, and 32c corresponding to the calculated combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF). Each of 32a, 32b, and 32c is stored in advance as a distribution function.

  The storage unit 43 also includes a combustor control temperature TITREF and state quantities of air flowing into the premixing chambers 31a, 31b, 31c (specifically, compressor discharge air pressure PX2, compressor discharge air temperature TX1, compressor discharge A distribution amount correction value (ratio) corresponding to either the air density ρ or the correction parameter C) is stored in advance as a correction function.

  The distribution control unit 45 distributes the total fuel flow rate control signal FREF based on the combustor control temperature TITREF and the distribution function, and distribution reference values FD1, FD2, FD2, which are distribution amounts before correction of the fuel control valves 11a, 11b, 11c, Find FD3. In addition, the distribution control unit 45 includes any one of the combustor control temperature TITREF, the air state quantity (specifically, the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, the compressor discharge air density ρ, and the correction parameter C). And distribution amount correction values FC2 and FC3 of the fuel control valves 11b and 11c are obtained based on the correction function. The distribution control unit 45 corrects the distribution reference values FD1, FD2, and FD3 with the distribution amount correction values FC2 and FC3 to obtain the flow rates F1, F2, and F3 for the fuel control valves 11a, 11b, and 11c, and the flow rates F1, F2 , F3 corresponding to the distribution fuel control signals FREF1, FREF2, and FREF3 are generated and output to the fuel control valves 11a, 11b, and 11c, and the total fuel flow and the fuel distribution for each of the premixed combustion burners 32a, 32b, and 32c. Control the rate.

The flow rates F1, F2, and F3 obtained by the distribution control unit 45 are based on the following relational expression.
F1 = TF × (FD1-FC2-FC3) ÷ 100
F2 = TF × (FD2 + FC2) ÷ 100
F3 = TF × (FD3 + FC3) ÷ 100
FD1 + FD2 + FD3 = 100%
TF: total fuel flow (total fuel flow control signal FREF)
F1: Fuel flow rate of the fuel control valve 11a F2: Fuel flow rate of the fuel control valve 11b F3: Fuel flow rate of the fuel control valve 11c FD1: Distribution amount before correction of fuel of the fuel control valve 11a (%)
FD2: Fuel distribution amount before correction of fuel control valve 11b (%)
FD3: Fuel distribution amount before correction of fuel control valve 11c (%)
FC2: fuel correction value of fuel control valve 11b (%)
FC3: fuel correction value of fuel control valve 11c (%)

The compressor discharge air density ρ is obtained from the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, and the compressor inlet air absolute humidity HX1 by the following equation.
ρ = {219.6 × (h + 1)} ÷ {(h + 0.622) × (273.15 + T)} × P ÷ 760
ρ: Compressor discharge air density (kg / m ^ 3)
T: Compressor discharge air temperature TX1 as combustion air temperature (° C)
P: Compressor discharge air pressure PX2 as combustion air pressure (kPa_abs)
h: Compressor inlet air absolute humidity HX1 as air compressor inlet absolute humidity (g / g)

Further, the correction parameter C is a value obtained by dividing the compressor discharge air pressure PX2 by the compressor discharge air temperature TX1 while ignoring the humidity item from the compressor discharge air density ρ, and is obtained by the following equation. Correction parameter C = P ÷ (273.15 + T)
P: Compressor discharge air pressure PX2 as combustion air pressure (kPa_abs)
T: Compressor discharge air temperature TX1 as combustion air temperature (° C)

  On the other hand, the fuel control device 12A that controls the fuel distribution amount of the gas turbine combustor 6A replaces the premixed combustion burner 32a of the gas turbine combustor 6 with the diffusion combustion burner 38 of the gas turbine combustor 6A.

  Specifically, the storage unit 43A stores the fuel distribution amount reference value for each of the diffusion combustion burner 38 and the premixed combustion burners 32b and 32c corresponding to the calculated combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF). The (ratio) is stored in advance as a distribution function for each of the diffusion combustion burner 38 and the premixed combustion burners 32b and 32c.

  The storage unit 43A also includes a combustor control temperature TITREF and a state quantity of air flowing into the premixing chambers 31a, 31b, 31c (specifically, compressor discharge air pressure PX2, compressor discharge air temperature TX1, compressor discharge A distribution amount correction value (ratio) corresponding to either the air density ρ or the correction parameter C) is stored in advance as a correction function.

  The distribution control unit 45A distributes the total fuel flow control signal FREF based on the combustor control temperature TITREF and the distribution function, and distribution reference values FD1, FD2, which are distribution amounts before correction of the fuel control valves 11a, 11b, 11c, Find FD3. In addition, the distribution control unit 45A includes any one of the combustor control temperature TITREF, the air state quantity (specifically, the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, the compressor discharge air density ρ, and the correction parameter C). And distribution amount correction values FC2 and FC3 of the fuel control valves 11b and 11c are obtained based on the correction function. Then, the distribution controller 45A corrects the distribution reference values FD1, FD2, and FD3 with the distribution amount correction values FC2 and FC3 to obtain the flow rates F1, F2, and F3 for the fuel control valves 11a, 11b, and 11c, and the flow rates F1, F2 , F3 corresponding to the distribution fuel control signals FREF1, FREF2, and FREF3 are generated and output to the fuel control valves 11a, 11b, and 11c, and the total fuel flow rate, the diffusion combustion burner 38, and the premixed combustion burners 32b and 32c are output. Control the fuel distribution rate.

  FIG. 5 is a diagram illustrating an example of a distribution function of the gas turbine combustor according to the first embodiment of the present invention.

  As shown in FIG. 5, the distribution function of the fuel control devices 12 and 12A according to the present embodiment is based on the fuel control valves 11a and 11b according to the value of the combustion temperature Tf of the combustion gas G (that is, the combustor control temperature TITREF). , 11c, the fuel distribution amount reference value is set.

  The distribution function is set from the viewpoint of the stability of the flame in the combustion chamber 33 and the suppression of the concentration of nitrogen oxides (NOx).

  The distribution function takes a large fuel distribution ratio (FD1) of the premixed combustion burner 32a or the diffusion combustion burner 38 in order to increase the stability of combustion in the low temperature region of the combustion temperature Tf (horizontal axis), while premixing is performed. The remaining amount of fuel is distributed (FD2, FD3) to the combustion burners 32b, 32c to suppress the generation of nitrogen oxides (NOx). Further, the distribution function gradually increases the combustion distribution ratio (FD2, FD3) of the premixed combustion burners 32b, 32c as the combustion temperature Tf increases, thereby improving the stability of the combustion of the premixed combustion burners 32b, 32c. The fuel distribution ratio (FD1) of the premixed combustion burner 32a or the diffusion combustion burner 38 is decreased, and the flame holding f (fire type) is decreased.

  FIGS. 6-8 is a figure which shows an example of the correction function of the gas turbine combustor which concerns on 1st Embodiment of this invention. FIG. 6 relates the combustion temperature of the combustion gas, the air pressure at the inlet of the gas turbine combustor, and the distribution amount correction value, and FIG. 7 shows the combustion temperature of the combustion gas, the air temperature at the inlet of the gas turbine combustor, and the distribution amount correction. FIG. 8 relates the combustion temperature of the combustion gas and the air density or correction parameter at the inlet of the gas turbine combustor and the distribution amount correction value.

  As shown in FIGS. 6 to 8, the correction functions of the fuel control devices 12 and 12A include the value of the combustion temperature Tf of the combustion gas G (that is, the combustor control temperature TITREF) and the inlets of the gas turbine combustors 6 and 6A. FC2 that is a fuel distribution amount correction value for each of the fuel control valves 11b and 11c is set according to any of the air pressure, air temperature, and air density.

  The combustion temperature Tf of the combustion gas G (that is, the combustor control temperature TITREF) is calculated from, for example, the turbine efficiency calculated from the air flow rate sucked by the compressor 3, the discharge pressure or pressure ratio of the compressor, and the exhaust gas temperature of the turbine 7. Alternatively, there is a method of calculating from the fuel-air ratio in the gas turbine combustors 6 and 6A and the composition of the combustion gas. In any of the methods, the combustion load in the gas turbine combustor cannot be expressed, and the change in the combustion load factor with the change in the state quantity of air cannot be handled. Therefore, the fuel control devices 12 and 12A store, as a correction function, a distribution amount correction value corresponding to the state quantity of the air flowing into the premixing chambers 31a, 31b, and 31c, and the air flowing into the premixing chambers 31a, 31b, and 31c. The distribution function is corrected according to the state quantity.

  6 to 8 show the fuel distribution amount correction value FC2 of the fuel control valve 11b, the fuel distribution amount correction value FC3 of the fuel control valve 11c is also set in the same manner. The distribution amount correction value FC3 may be obtained by multiplying the distribution amount correction value FC2 by “−1”. In this case, F1 = TF × FD1 ÷ 100, and the fuel flow rate of the fuel control valve 11a is determined by the pre-correction distribution amount.

  These distribution amount correction value FC2 and distribution amount correction value FC3 are set as appropriate based on operational results of the gas turbine power plant 1 such as experiments, tests, and operations, and respond to changes in the combustion load factor accompanying changes in the air state quantity. Then, the stability of combustion is increased, and the setting is made in advance to suppress the generation of nitrogen oxides (NOx). The upper limit of the distribution amount correction values FC2 and FC3 is + 3%, and the lower limit is −3%.

  That is, the control method of the fuel control device 12 applied to the gas turbine combustor 6 is the fuel distribution amount reference value and the premixing chamber for each of the premixing chambers 31a, 31b, 31c corresponding to the combustion temperature calculation value of the combustion gas G. The distribution amount correction value corresponding to the state quantity of air flowing into 31a, 31b, 31c is determined in advance, the combustion temperature of the combustion gas G is calculated from the state quantity of the gas turbine 7, and the air flowing into the premixing chambers 31a, 31b, 31c , And the distribution amount reference value is corrected with the distribution amount correction value from the calculation result of the combustion temperature and the measurement result of the state amount of the air flowing into the premixing chambers 31a, 31b, 31c. The distribution amount of the fuel for each of the air flowing into 31b and 31c is controlled.

  Further, the control method of the fuel control device 12 applied to the gas turbine combustor 6A is that the premixing chamber 31b corresponding to the combustion temperature calculation value of the combustion gas G, the fuel distribution amount reference value for each 31c, and the premixing chamber 31b, A distribution amount correction value corresponding to the state quantity of air flowing into 31c is determined in advance, the combustion temperature of combustion gas G is calculated from the state quantity of gas turbine 7, and the state quantity of air flowing into premixing chambers 31b and 31c is measured. The distribution amount reference value is corrected with the distribution amount correction value from the calculation result of the combustion temperature and the measurement result of the state quantity of the air flowing into the premixing chambers 31b and 31c, and the air flowing into the premixing chambers 31b and 31c is corrected. Control the amount of fuel distribution.

  According to the gas turbine combustors 6 and 6A, the gas turbine 7 and the control method according to the present embodiment configured as described above, the combustion load in the combustion chamber 33 that is difficult to represent even if the combustion temperature of the combustion gas G is calculated. On the other hand, the fuel is based on the state quantity of the air flowing into the premixing chambers 31a, 31b, 31c (any one of the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, the compressor discharge air density ρ, and the correction parameter C). It becomes possible to correct the fuel distribution amount of the control valves 11a, 11b, and 11c, increase the stability of the premixed combustion against changes in the combustion load factor, and suppress the generation of nitrogen oxides (NOx). . In other words, even if the calculation method is applied as in the conventional gas turbine combustor or the combustion temperature of the combustion gas is obtained by actually measuring the temperature in the combustion chamber, the combustion accompanying the change in the state quantity of air Where it is difficult to cope with a change in the load factor, the gas turbine combustors 6 and 6A, the gas turbine 7 and the control method according to the present embodiment have a state quantity of air flowing into the premixing chambers 31a, 31b and 31c. The relationship with the change in the combustion load factor can be expressed by a correction function, and the fuel distribution amount of the fuel control valves 11a, 11b, and 11c can be corrected to cope with the change in the combustion load factor. It is possible to increase the stability of premixed combustion with respect to and to suppress the generation of nitrogen oxides (NOx).

[Second Embodiment]
A gas turbine combustor, a gas turbine, and a gas turbine combustor control method according to a second embodiment of the present invention will be described with reference to FIGS. 9 to 16.

  FIG. 9 is a schematic system configuration diagram showing a gas turbine combustor according to a second embodiment of the present invention.

  FIG. 10 is a schematic system configuration diagram showing another example of the gas turbine combustor according to the second embodiment of the present invention.

  In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIGS. 9 and 10, the gas turbine combustors 6B and 6C according to the present embodiment close the fuel control valve 11a when the combustion of the combustion gas G is stabilized, and the premixed combustion burner 32a or the diffusion combustion burner 38. Extinguish flame holding (fire type) f. Therefore, the gas turbine combustors 6B and 6C include a replacement air valve 51a capable of supplying the replacement air SA1 to the premixed combustion burner 32a or the diffusion combustion burner 38. The gas turbine combustors 6B and 6C also include replacement air valves 51b and 51c capable of supplying replacement air SA2 and SA3 to the premixed combustion burners 32b and 32c.

  FIG. 11 is a control block diagram of a gas turbine power plant to which the gas turbine combustor according to the second embodiment of the present invention is applied.

  As shown in FIG. 11, in the case of the gas turbine combustor 6B, the fuel control device 12B has a replacement air flow rate corresponding to a combustion temperature calculation value of the combustion gas G and a state quantity of air flowing into the premixing chambers 31a, 31b, 31c. Is stored in advance, and when the fuel distribution is stopped in any one of the premixing chambers 31a, 31b, 31c (specifically, the premixed combustion burner 32a), the combustion temperature calculation result and Control the flow rate of air replacing the premixing chamber 31a, which stops the fuel distribution by correcting the replacement air flow rate with the replacement air flow rate correction value from the measurement result of the state quantity of the air flowing into the premixing chambers 31a, 31b, 31c. To do.

  In addition to the distribution function and the correction function, the storage unit 43B stores in advance the valve opening of the replacement air valve 51a corresponding to the calculated combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF) as a replacement air flow rate function. To do. The valve opening of the replacement air valve 51a corresponds to the replacement air flow rate of the premixed combustion burner 32a.

  The storage unit 43B also includes a combustor control temperature TITREF and state quantities of air flowing into the premixing chambers 31a, 31b, 31c (specifically, compressor discharge air pressure PX2, compressor discharge air temperature TX1, compressor discharge A replacement air flow rate correction value (ratio) corresponding to either the air density ρ or the correction parameter C) is stored in advance as a replacement air flow rate correction function.

  The distribution control unit 45B generates distribution fuel control signals FREF1, FREF2, and FREF3, controls the total fuel flow rate and the fuel distribution ratio for each of the premixed combustion burners 32b and 32c, and generates a replacement air control signal AREF1. . The flow rate of the replacement air in the premixed combustion burner 32a is controlled. Specifically, the distribution control unit 45B obtains the pre-correction valve opening AD1 of the replacement air valve 51a based on the combustor control temperature TITREF and the replacement air flow rate function. In addition, the distribution control unit 45B includes any one of the combustor control temperature TITREF, the air state quantity (specifically, the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, the compressor discharge air density ρ, and the correction parameter C). ) And the replacement air flow rate correction function, the valve opening correction value AC1 of the replacement air valve 51a is obtained. Then, the distribution control unit 45B obtains the valve opening SA1 of the replacement air valve 51a by correcting the pre-correction valve opening AD1 with the valve opening correction value AC1, and obtains the replacement air control signal AREF1 corresponding to the valve opening SA1. This is output to the replacement air valve 51a, and the flow rate of the replacement air in the premixed combustion burner 32a is controlled.

  On the other hand, the fuel control device 12C that controls the fuel distribution amount of the gas turbine combustor 6C replaces the premixed combustion burner 32a of the gas turbine combustor 6B with the diffusion combustion burner 38 of the gas turbine combustor 6C.

  That is, in the case of the gas turbine combustor 6C, the fuel control device 12C sets the replacement air flow rate correction value corresponding to the replacement air flow rate corresponding to the combustion temperature calculation value of the combustion gas G and the state quantity of the air flowing into the diffusion combustion burner 38. When storing the fuel in the diffusion combustion burner 38 in advance, the replacement air flow rate is corrected by the replacement air flow rate correction value from the combustion temperature calculation result and the measurement result of the state quantity of the air flowing into the diffusion combustion burner 38. Thus, the flow rate of the air replacing the diffusion combustion burner 38 is controlled.

  In addition to the distribution function and the correction function, the storage unit 43C previously stores the valve opening degree of the replacement air valve 51a corresponding to the calculated combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF) as a replacement air flow rate function. To do. The valve opening degree of the replacement air valve 51a corresponds to the replacement air flow rate of the diffusion combustion burner 38.

  In addition, the storage unit 43C stores the combustor control temperature TITREF and the state quantity of air flowing into the diffusion combustion burners 38, 31b, 31c (specifically, the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, the compressor discharge A replacement air flow rate correction value (ratio) corresponding to either the air density ρ or the correction parameter C) is stored in advance as a replacement air flow rate correction function.

  The distribution control unit 45C generates distribution fuel control signals FREF1, FREF2, and FREF3, controls the total fuel flow rate and the fuel distribution ratio for each of the premixed combustion burners 32b and 32c, and generates a replacement air control signal AREF1. . The flow rate of the replacement air in the diffusion combustion burner 38 is controlled. Specifically, the distribution control unit 45C obtains the pre-correction valve opening AD1 of the replacement air valve 51a based on the combustor control temperature TITREF and the replacement air flow rate function. In addition, the distribution control unit 45C includes any one of the combustor control temperature TITREF, the air state quantity (specifically, the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, the compressor discharge air density ρ, and the correction parameter C). ) And the replacement air flow rate correction function, the valve opening correction value AC1 of the replacement air valve 51a is obtained. Then, the distribution control unit 45C obtains the valve opening SA1 of the replacement air valve 51a by correcting the pre-correction valve opening AD1 with the valve opening correction value AC1, and obtains the replacement air control signal AREF1 corresponding to the valve opening SA1. This is generated and output to the replacement air valve 51a, and the flow rate of the replacement air in the diffusion combustion burner 38 is controlled.

  FIG. 12 is a diagram illustrating an example of a distribution function of the gas turbine combustor according to the second embodiment of the present invention.

  As shown in FIG. 12, the distribution functions of the fuel control devices 12B and 12C according to the present embodiment are based on the fuel control valves 11a, 11b, and 11b according to the combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF). A fuel distribution amount reference value for each 11c is set.

  The distribution function is set from the viewpoint of the stability of the flame in the combustion chamber 33 and the suppression of the concentration of nitrogen oxides (NOx).

  In the low temperature region of the combustor control temperature TITREF (horizontal axis), the distribution function takes a large fuel distribution ratio of the premixed combustion burner 32a or the diffusion combustion burner 38 in order to increase the stability of the combustion, The remaining amount of fuel is distributed to the premixed combustion burners 32b and 32c that suppress the generation of (NOx). Further, the distribution function stops the fuel distribution of the premixed combustion burner 32a or the diffusion combustion burner 38 while gradually increasing the combustion distribution ratio of the premixed combustion burners 32b and 32c as the combustor control temperature TITREF increases. To do. In this process, the distribution function increases the fuel distribution amount of one of the premixed combustion burners 32b and 32c (for example, the premixed combustion burner 32c) to increase the stability of the premixed combustion, and the premixed combustion burner 32b. , 32c (for example, the premixed combustion burner 32b) reduces the amount of fuel distributed to suppress the generation of nitrogen oxides (NOx).

  The correction function is the same as that shown in FIGS. The distribution amount correction value FC is set as appropriate based on operational results of the gas turbine power plant 1 such as experiments, tests, and operations, and the stability of combustion is adjusted in accordance with the change in the combustion load factor accompanying the change in the air state quantity. And set in advance to suppress the generation of nitrogen oxides (NOx).

The flow rates F1, F2, and F3 obtained by the distribution control units 45B and 45C of the fuel control devices 12B and 12C according to the present embodiment are based on the following relational expressions. The following relational expression is applied to the section where F1 = 0 in FIG.
F1 = 0
F2 = TF × (FD2 + FC) ÷ 100
F3 = TF × (FD3-FC) ÷ 100
FD2 + FD3 = 100%
SA1 = AD1 + AC1 ÷ 100
TF: total fuel flow (total fuel flow control signal FREF)
F1: Fuel flow rate of the fuel control valve 11a F2: Fuel flow rate of the fuel control valve 11b F3: Fuel flow rate of the fuel control valve 11c FD2: Pre-correction distribution amount (%) of the fuel control valve 11b
FD3: Fuel distribution amount before correction of fuel control valve 11c (%)
FC: Fuel correction value (%) for fuel control valves 11b and 11c
SA1: Valve opening degree (or flow rate) of the air of the replacement air valve 51a
AD1: Pre-correction valve opening of the replacement air valve 51a (or pre-correction flow rate)
AC1: Replacement air flow rate correction value (%) of the replacement air valve 51a
Since the replacement air valves 51b and 51c are closed, SA2 = SA3 = 0.

  FIG. 13 is a diagram illustrating an example of a replacement air supply function of the gas turbine combustor according to the second embodiment of the present invention.

  As shown in FIG. 13, the replacement air supply function of the fuel control devices 12B and 12C according to the present embodiment is based on the value of the combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF). Set the valve opening or flow rate.

  The replacement air supply function starts supplying the replacement air to the premixed combustion burner 32a or the diffusion combustion burner 38 so as to replace it when the fuel of the premixed combustion burner 32a or the diffusion combustion burner 38 is stopped. Further, the replacement air supply function gradually increases the supply amount of the replacement air as the combustor control temperature TITREF rises, and prevents moisture from staying in the premixed combustion burner 32a or the diffusion combustion burner 38.

  FIGS. 14 to 16 are diagrams illustrating an example of a replacement air flow rate correction function of the gas turbine combustor according to the second embodiment of the present invention. FIG. 14 relates the combustion temperature of the combustion gas, the air pressure at the inlet of the gas turbine combustor, and the replacement air flow correction value, and FIG. 15 shows the combustion temperature of the combustion gas, the air temperature at the inlet of the gas turbine combustor, and the replacement air. FIG. 16 relates the combustion temperature of the combustion gas and the air density or correction parameter at the inlet of the gas turbine combustor and the replacement air flow correction value.

  As shown in FIGS. 13 to 15, the replacement air flow rate correction function of the fuel control devices 12B and 12C includes the combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF) and the gas turbine combustors 6 and 6A. The replacement air flow rate correction value of the replacement air valve 51a is set according to any of the air pressure, air temperature, and air density at the inlet of the air.

  The combustion temperature of the combustion gas G (that is, the combustor control temperature TITREF) is calculated from, for example, the turbine efficiency calculated from the air flow rate sucked by the compressor 3, the discharge pressure or pressure ratio of the compressor, and the exhaust gas temperature of the gas turbine 7. Alternatively, there is a method of calculating from the fuel-air ratio in the gas turbine combustors 6 and 6A and the composition of the combustion gas. In any of the methods, the combustion load in the gas turbine combustor cannot be expressed, and the change in the combustion load factor with the change in the state quantity of air cannot be handled. Therefore, the fuel control devices 12B, 12C store the replacement air flow rate correction value corresponding to the state quantity of the air flowing into the premixing chambers 31a, 31b, 31c as a replacement air flow rate correction function, and the premixing chambers 31a, 31b, 31c. The replacement air supply function is corrected according to the state quantity of the air flowing into the air.

  The replacement air flow rate correction value AC1 is set as appropriate based on operational results of the gas turbine power plant 1 such as experiments, tests, and operations, and the stability of combustion corresponding to the change in the combustion load factor accompanying the change in the air state quantity. Is set in advance so as to suppress the generation of nitrogen oxides (NOx). The upper limit of the replacement air flow rate correction value AC1 is + 30%, and the lower limit is −30%.

  According to the gas turbine combustors 6B and 6C, the gas turbine 7 and the control method according to the present embodiment configured as described above, the combustion load in the combustion chamber 33 that is difficult to represent even if the combustion temperature of the combustion gas G is calculated. On the other hand, the fuel is based on the state quantity of the air flowing into the premixing chambers 31a, 31b, 31c (any one of the compressor discharge air pressure PX2, the compressor discharge air temperature TX1, the compressor discharge air density ρ, and the correction parameter C). It becomes possible to correct the fuel distribution amount of the control valves 11a, 11b, and 11c, increase the stability of the premixed combustion against changes in the combustion load factor, and suppress the generation of nitrogen oxides (NOx). . In other words, even if the calculation method is applied as in the conventional gas turbine combustor or the combustion temperature of the combustion gas is obtained by actually measuring the temperature in the combustion chamber, the combustion accompanying the change in the state quantity of air Where it is difficult to cope with changes in the load factor, the gas turbine combustors 6B and 6C, the gas turbine 7 and the control method according to the present embodiment have the state quantity of air flowing into the premixing chambers 31a, 31b and 31c. The relationship with the change in the combustion load factor can be expressed by a correction function, and the fuel distribution amount of the fuel control valves 11a, 11b, and 11c can be corrected to cope with the change in the combustion load factor. It is possible to increase the stability of premixed combustion with respect to and to suppress the generation of nitrogen oxides (NOx).

  Therefore, according to the control method for the gas turbine combustors 6, 6A, 6B, 6C, the gas turbine 7, and the gas turbine combustor according to the present embodiment, the combustion load factor in the gas turbine combustors 6, 6A, 6B, 6C. In response to this change, combustion can be stabilized and generation of nitrogen oxides (NOx) can be suppressed.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Gas turbine power plant 2 Inlet guide vane 3 Compressor 5 Air flow path 6, 6A, 6B, 6C Gas turbine combustor 7 Gas turbine 8 Generator 9 Turbine shaft 11a, 11b, 11c Fuel control valve 12, 12A, 12B, 12C Fuel control device 13 Shaft end gear 15 Speed detector 21 Inlet air pressure detector 22 Compressor discharge air pressure detector 23 Compressor discharge air temperature detector 25 Exhaust gas temperature detector 26 Generator output detectors 29a, 29b, 29c Fuel nozzles 31a, 31b, 31c Premixing chambers 32a, 32b, 32c Premixed combustion burner 33 Combustion chamber 35 Hollow barrel 36 Transition piece 38 Diffusion combustion burner 41 Total fuel flow rate calculation unit 42 Combustor temperature calculation units 43, 43A, 43B, 43C Storage unit 45, 45A, 45B, 45C Distribution control unit 51a, 51b, 51c Valve

Claims (6)

Multiple fuel valves with adjustable fuel flow rates;
A plurality of premixed combustion burners having a premixing chamber that mixes the fuel and air flowing from the fuel valve into a premixed gas;
A hollow cylinder having a combustion chamber for combusting the premixed gas taken from the premixed combustion burner to generate combustion gas;
The fuel distribution amount reference value corresponding to the premixing chamber corresponding to the combustion temperature calculation value of the combustion gas and the distribution amount correction value corresponding to the state amount of the air flowing into the premixing chamber are stored in advance, and the gas turbine The combustion gas combustion temperature is calculated from the state quantity and the state quantity of the air flowing into the premixing chamber is measured, and the distribution quantity reference value is corrected with the distribution quantity correction value from the calculation result and the measurement result. A control unit for controlling the distribution amount of the fuel for each fuel valve,
The control unit stores in advance a replacement air flow rate corresponding to a combustion temperature calculation value of the combustion gas and a replacement air flow rate correction value corresponding to a state quantity of air flowing into the premixing chamber. When the fuel distribution is stopped, the premixing chamber stops the fuel distribution by correcting the replacement air flow rate with the replacement air flow rate correction value from the combustion temperature calculation result and the state quantity measurement result. features and to Ruga turbines combustor to control the flow rate of the air to replace. A diffusion combustion burner for diffusing and burning the fuel flowing from the fuel valve in the combustion chamber;
The control unit stores in advance a replacement air flow rate corresponding to a combustion temperature calculation value of the combustion gas and a replacement air flow rate correction value corresponding to a state quantity of air flowing into the diffusion combustion burner, and the diffusion combustion burner When stopping fuel distribution, the flow rate of the air replacing the diffusion combustion burner is controlled by correcting the replacement air flow rate with the replacement air flow rate correction value from the combustion temperature calculation result and the state quantity measurement result. The gas turbine combustor according to claim 1 . The state quantity, according to claim 1 or 2, wherein the pressure of the air flowing into the premix chamber or the diffusion combustion burner, temperature, density, and the pressure is either divided by the said temperature Gas turbine combustor. A gas turbine comprising the gas turbine combustor according to any one of claims 1 to 3 . A plurality of fuel valves capable of adjusting the flow rate of fuel; a plurality of premixers having a premixing chamber connected to the fuel valves to mix the fuel and air to form a mixture; and the premixer A gas turbine combustor control method comprising: a hollow cylinder having a combustion chamber connected to convert the mixture into combustion gas,
The fuel distribution amount reference value for each premixing chamber corresponding to the combustion temperature calculation value of the combustion gas and a distribution amount correction value corresponding to the state quantity of air flowing into the premixing chamber are determined in advance
Calculate the combustion temperature of the combustion gas from the state quantity of the gas turbine,
Measure the amount of state of air flowing into the premixing chamber,
From the calculation result of the combustion temperature and the measurement result of the state quantity, the distribution quantity reference value is corrected with the distribution quantity correction value to control the fuel distribution quantity for each premixing chamber,
A replacement air flow rate correction value corresponding to a replacement air flow rate corresponding to a combustion temperature calculation value of the combustion gas and a state quantity of air flowing into the premixing chamber is determined in advance,
When stopping the fuel distribution in any of the premixing chambers, the fuel distribution is performed by correcting the replacement air flow rate with the replacement air flow rate correction value from the calculation result of the combustion temperature and the measurement result of the state quantity. the method features and be Ruga turbines combustor to control the flow rate of the air to replace the premixing chamber to stop. The gas turbine combustor includes a diffusion combustion burner that is connected to the fuel valve and diffuses combustion in the combustion chamber.
A replacement air flow rate correction value corresponding to a replacement air flow rate corresponding to a combustion temperature calculation value of the combustion gas and a state quantity of air flowing into the diffusion combustion burner is determined in advance,
When the fuel distribution of the diffusion combustion burner is stopped, the diffusion combustion burner is replaced by correcting the replacement air flow rate with the replacement air flow rate correction value from the calculation result of the combustion temperature and the measurement result of the state quantity. The method of controlling a gas turbine combustor according to claim 5 , wherein a flow rate of the air is controlled.

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