JP4515330B2 - High humidity gas turbine equipment, control device and control method thereof - Google Patents

Description

  The present invention relates to a high-humidity gas turbine facility that humidifies compressed air combusted in a gas turbine combustor, a control device and a control method therefor.

  In recent years, high-humidity gas turbine equipment that improves the output and efficiency by humidifying compressed air combusted in a gas turbine combustor has been proposed, and is expected to be used for small-scale power generation for plants and cogeneration. ing. This high-humidity gas turbine equipment is more efficient than conventional gas turbine equipment because the volume flow of combustion air increases when humidified. In addition, since the combustion temperature decreases due to an increase in the humidity of the combustion air, it is possible to suppress an increase in the temperature of each part of the turbine and emission of nitrogen oxides.

  In this type of high-humidity gas turbine equipment, generally, compressed air from a compressor humidified by a humidifier is led to a regenerative heat exchanger, where combustion air heated by exhaust gas discharged from the turbine is combined with fuel. Burn in the combustor. Supply water to be added to the compressed air is temporarily stored in a tank that has been preheated with compressed air from a compressor in an air cooler and that preheated with exhaust gas from a turbine in a feed water heater. It is known that the stored water inside is supplied to the humidifier (see Patent Document 1).

JP-A-11-257096

  In the high-humidity gas turbine equipment, when the compressed air for combustion starts to be humidified, the combustion temperature decreases, and the heat recovery amount of the exhaust gas in the regeneration heat exchanger 11 and the feed water heater 12 varies. As a result, the temperature of the feed water that has passed through the feed water heater 12 decreases, and after a certain period of time, the amount of humidification in the humidifier decreases and the exhaust gas temperature begins to rise. These cycles are repeated at the start and stop of humidification of compressed air, and the temperature, pressure, flow rate, and humidity of the entire system including the gas turbine fluctuate periodically, and the amount of power generation and the frequency of produced electricity are unstable for a long time. It becomes. For this reason, it takes a long time to start and stop the plant, and it is difficult to ensure sufficient load followability when the load changes. In small-scale facilities and cogeneration, it is necessary to start / stop / load the plant sequentially in response to fluctuations in daily power demand and steam demand, which improves operational efficiency such as improving load change rate and shortening start / stop time. Improvement is required.

  An object of the present invention is to provide a high-humidity gas turbine equipment that can stabilize the operation state at the time of starting and stopping in a short time and improve the followability to a load change, a control device and a control method therefor.

  In order to achieve the above-mentioned object, the present invention supplies a humidifier with water supplied from an air cooler in a high-humidity gas turbine facility that humidifies compressed air combusted in a gas turbine combustor with a humidifier. A first control valve that can change the ratio of whether to drain or drain, a second control valve that can change the ratio of whether the feed water from the feed water heater is supplied to the humidifier or drain, and the first And a control device that controls the second control valve to adjust the humidification amount of the compressed air in the humidifier.

  According to the present invention, since the mixer can adjust the temperature of the supply water added to the compressed air by the humidifier and adjust the humidification amount of the compressed air in stages, the operating state at the time of starting and stopping can be shortened. It is possible to stabilize with time and improve the follow-up to the load change.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a circuit diagram showing a schematic configuration of a high-humidity gas turbine system according to an embodiment of the present invention.
This system includes a compressor 2 that compresses air, a humidifier 8 that humidifies at least a part of the air (compressed air) compressed by the compressor 2, and compressed air humidified by the humidifier 8. , The turbine 1 driven by the combustion gas generated by the combustor 3, the exhaust gas discharged from the turbine 1 and the humidifier supplied from the humidifier 8 to the combustor 3. A regenerative heat exchanger 11 that exchanges heat with air, a feed water heater 12 that preheats supply water that humidifies compressed air with a humidifier 8 with exhaust gas from the turbine 1, and compressed air with a humidifier 8. An air cooler 32 that preheats the feed water that humidifies the air with compressed air from the compressor 2, a mixer 29 that mixes the feed water preheated with the feed water heater 12 and the feed water preheated with the air cooler 32, The moisture of the exhaust gas that has passed through the feed water heater 12 is rotated. The water recovery device 15 to be used, the air cooler outlet three-way valve 18 capable of changing the ratio of the water supplied from the air cooler 32 to the mixer 29 and the water recovery device 15, and the water supplied from the feed water heater 12 The feed water heater outlet three-way valve 17 that can change the ratio of the gas introduced to the mixer 29 and the water recovery device 15 and the opening degree of these three-way valves 17 and 18 are controlled to control the compressed air in the humidifier 8. And a humidifier control means for adjusting the humidification amount (humidity).

  The air cooler 32 is a device that recovers heat from the compressed air obtained by the compressor 2. The amount of heat recovered from the compressed air by the air cooler 32 is used for preheating the feed water sprayed by the humidifier 8. Further, the air cooler 32 boils the supply water flowing down in the humidifier 8 by gas-liquid contact when the compressed air whose temperature is increased and increased in pressure by the compressor 2 flows into the humidifier 8 as it is.・ It prevents evaporation. That is, by reducing the temperature of the compressed air before it flows into the humidifier 8 by the air cooler 32, it serves to prevent a sudden increase in humidity of the compressed air in the humidifier 8.

  The feed water heater 12 is a device that recovers the heat of the exhaust gas from the turbine 1 that has passed through the regenerative heat exchanger 11. The amount of heat of the exhaust gas recovered by the feed water heater 12 is used for preheating the feed water sprayed by the humidifier 8.

  The feed water heated by the feed water heater 12 and the feed water heated by the air cooler 32 flow down inside the humidifier 8 and are temporarily stored at the bottom of the humidifier 8, and then humidified by the pump 24. It is supplied from the lower part of the vessel 8 to the air cooler 32 and the feed water heater 12. The supply water guided to the air cooler 32 side is supplied to the mixer 29 via the air cooler outlet three-way valve 18. The feed water guided to the feed water heater 12 side is fed to the mixer 29 via the feed water heater outlet three-way valve 17. These three-way valves 17 and 18 can adjust the ratio of water supply to the mixer 29 and the blow pipe 26 that have passed through the feed water heater 17 or the air cooler 18. The opening degree of the three-way valves 17 and 18 is controlled by a command from the humidifier controller 101. In addition, the supply water sent to the blow pipe 26 is drained to the water recovery device 15. For example, while the humidifier 8 is stopped, the three-way valves 17 and 18 are respectively switched to the blow pipe 26 side to drain the supplied water to the water recovery device 15 and during operation of the humidifier 8 (when humidifying compressed air). Switches the three-way valves 17 and 18 to the humidifier 8 side and supplies them to the mixer 29.

  The mixer 29 mixes the supply water from the air cooler 32 and the feed water heater 12, and is a mere junction of the feed water line from the air cooler 32 and the feed water line from the feed water heater 12. is there. The supply water merged in the mixer 29 is supplied to the humidifier 8 without being stored in the mixer 29. The humidifier 8 is a device that adds moisture to the compressed air through a filling enclosed inside. The feed water sprayed from the upper part in the humidifier 8 humidifies the compressed air to the saturation point by the action of gas-liquid contact while flowing down on the surface of the filling. Humidified compressed air is referred to herein as humidified air. When the supply water at the bottom of the humidifier 8 is insufficient, the pump 22 is driven to replenish from the stored water in the water recovery device 15.

  The humidified air that has exited the humidifier 8 is guided to the regenerative heat exchanger 11 via the pipe 9, where the temperature is raised by exchanging heat with the exhaust gas from the turbine 1. As a result, the humidified air rises to about the temperature of the exhaust gas from the turbine 1 and passes through the regenerative heat exchanger 11 so that the moisture in the humidified air is completely evaporated. The humidified air (referred to as combustion air) that has passed through the regenerative heat exchanger 11 is guided to the combustor 3 via the pipe 13.

  In the combustor 3, the combustion air obtained by the regenerative heat exchanger 11 is mixed with the fuel pressurized by the fuel pump 5 and burned. The fuel flow rate is adjusted by controlling the opening degree of the fuel flow rate adjustment valve 6 according to a command from the fuel flow rate adjustment valve control device 102. The shaft power of the turbine 1 obtained by the expansion work of the combustion gas is transmitted to the compressor 2 and the generator 4 through the shaft 20. A part of the shaft power of the turbine 1 is used for pressurization of air in the compressor 2, and the rest is converted into electric power in the generator 4. The combustion gas (that is, exhaust gas) that has driven the turbine 1 and passed through the turbine 1 is guided to the flue 14. A part of the thermal energy of the combustion gas led to the flue 14 is recovered by the regenerative heat exchanger 11 and the feed water heater 12 as described above, and used for heating the humidified air and preheating the feed water. The exhaust gas whose heat has been recovered by the regenerative heat exchanger 11 and the feed water heater 12 is guided to the water recovery device 15 via the flue 28.

  Water in the exhaust gas from the turbine 1 is recovered by the water recovery device 15. This water recovery device 15 is a system in which water is sprayed onto the flue to collect and collect water in the exhaust gas by agglomerating and dropping. The agglomerated water is stored in a liquid pool at the bottom of the water recovery device 15 and supplied to the humidifier 8 by the pump 22 as necessary, as well as being pumped up by the pump 21 and stored in the water recovery device 15 as described above. Sprayed from above. At that time, in order to effectively collect moisture in the exhaust gas, water sprayed in the water recovery device 15 is cooled by the cooling heat exchanger 25 while being pumped up by the pump 21. The exhaust gas whose water has been recovered by the water recovery device 15 is discharged to the atmosphere via the chimney 27. Further, if the stored water is insufficient in the water recovery device 15, water such as a water storage tank (not shown) is replenished by the pump 23.

  Here, the outlet of the mixer 29 is provided with a feed water temperature detector 30 that measures the temperature of the feed water supplied to the humidifier 8. An exhaust temperature detector 31 that measures the temperature of exhaust gas discharged from the turbine 1 is provided at the outlet of the turbine 1. The detection result of the exhaust gas temperature detector 31 is output to the gas turbine control device 100.

  The gas turbine control device 100 receives a load request command (Unit Demand) UD from a central power supply command station (not shown), and outputs a fuel flow command (Fuel Demand) FD so that the plant power generation output follows the load request command UD. Output. The fuel flow command FD is output to the humidifier control device 101 and the fuel flow control valve control device 102 described above. At this time, in this embodiment, when the turbine outlet exhaust temperature Tx (measured value) detected by the exhaust temperature detector 31 described above for the purpose of safety protection exceeds the set value, the fuel flow rate command FD is suppressed and the temperature rises. Prevents damage to the gas turbine. Further, since the turbine outlet exhaust temperature Tx is also used as an index for grasping the performance or operating state of the gas turbine, in this embodiment, it is also used as a reference for determining the plant stabilization.

  Then, the fuel flow rate adjustment valve control device 102 outputs a fuel adjustment valve opening signal 110 corresponding to the fuel flow rate command FD, and controls the opening degree of the fuel flow rate adjustment valve 6. On the other hand, the humidifier control device 101 inputs the fuel flow rate command FD from the gas turbine control device 100 and the mixer outlet temperature Tw from the feed water temperature detector 30, and the air cooler outlet three-way valve 18 according to these input signals. The air cooler outlet three-way valve opening command Cva and the feed water heater outlet three-way valve opening command Cvb for the feed water heater outlet three-way valve 17 are calculated and output.

  When the high-humidity gas turbine plant of the present embodiment configured as described above is started, first, the pump 23 is driven to store the supply water at the bottom of the water recovery device 15, and then the pump 22 is driven to increase the humidity. Feed water is led to the bottom of the vessel 8. Next, the pump 24 is driven and the air cooler 32 → the air cooler outlet three-way valve 18 → the blow pipe 26 → the pump 22 → the path of the humidifier 8 or the feed water heater 12 → the feed water heater outlet three-way valve 17 → the blow pipe. The supply water is circulated through a route of 26 → pump 22 → humidifier 8. By circulating the supply water in this way, air supply of the air cooler 32 and the feed water heater 12 at the time of turbine start-up and load operation is avoided, and the feed water in the air cooler 32 and the feed water heater 12 is avoided. Prevent boiling (steaming phenomenon).

  Next, the gas turbine is started, and the compressed air is supplied to the combustor 3 through the path of the compressor 2 → the pipe 7 → the air cooler 32 → the humidifier 8 → the pipe 9 → the regenerative heat exchanger 11 → the pipe 13 → the combustor 3. Lead. In consideration of the stability of the combustor 3, the supply water to the air cooler 32 and the feed water heater 12 is discharged from the blow pipe 26 at the start-up, and the humidifier 8 does not yet humidify the compressed air. The combustion gas generated in the combustor 3 is driven through the chimney 27 after driving the turbine 1 and then passing through the flue 14 → the regenerative heat exchanger 11 → the feed water heater 12 → the flue 28 → the water recovery device 15.

  When the gas turbine starts, the humidifier 8 is started next. When the humidifier 8 is started, the air cooler outlet three-way valve 18 and the feed water heater outlet three-way valve 17 are appropriately switched to the mixer 29 side, and the compressed air from the compressor 2 is supplied by the supply water supplied through the mixer 29. Start humidifying with the following procedure.

FIG. 2 is a flowchart showing an example of a start / stop procedure of the humidifier 8 by the humidifier controller 101.
In step 201, it is determined whether or not the humidifier 8 can be started / stopped from the fuel flow rate command FD. That is, whether the humidifier 8 can be started or stopped is determined from the state of the fuel flow rate to the combustor 3. For example, when the humidifier 8 is started in a state where the fuel flow rate command FD is low, the combustion becomes unstable due to an increase in the humidification amount. Conversely, when the humidifier 8 is stopped with the fuel flow rate command FD being high, the turbine outlet exhaust temperature rises to the trip temperature. Therefore, in step 201, in order not to cause such a problem, when the value of the fuel flow command FD exceeds the set value A, the humidifier 8 is in a driving state, and the value of the fuel flow command FD is set to the set value B (<A). If it falls below, it is determined whether or not the humidifier 8 can be started / stopped so that the humidifier 8 is stopped (see also step 201 in FIG. 2). In the subsequent step 202, the operation mode (start or stop) of the humidifier 8 is determined from the determination result in step 201. If the humidifier 8 is started as a result of the determination, the humidifier 8 is stopped in step 203. If so, go to Step 207.

  In step 203, the opening degree to the air cooler outlet three-way valve 18 is set so that the supply ratio of feed water preheated by the air cooler 32 to the mixer 29 (0% at this time) becomes 100%. Command Cva is calculated and output. As a result, the humidity of the humidified air supplied from the humidifier 8 to the combustor 3 increases. At this time, as the humidification amount increases, the combustion temperature decreases and the heat balance of the plant fluctuates, but the balance fluctuation due to the switching of the supply water from the air cooler side is temporary and the turbine exhaust temperature decreases. It becomes the characteristic that becomes stable after.

  In the next step 204, fluctuations in the turbine exhaust temperature Tx detected by the exhaust temperature detector 31 and the fuel flow rate command FD transmitted from the gas turbine control device 100 are monitored for a certain period of time, and the gas turbine is stabilized from the fluctuation range. It is determined whether the procedure can be transferred to the subsequent steps. There are various methods for determining the stabilization. Here, as shown in the following (formula 1) to (formula 3), the turbine exit exhaust gas is calculated from the turbine exit exhaust temperature Tx and the time series signal of the fuel flow rate command FD in a certain section. A method of calculating an average value of each of the temperature Tx and the fuel flow rate command FD and a dispersion sum after normalization of the turbine outlet exhaust temperature Tx and the fuel flow rate command FD, and determining a static value using these calculation results. Using.

  Here, T is the current time, Δt is the sampling period of the measurement values Tx and FD, and N is the number of data samples of Tx and FD. J is an index for determining that the gas turbine has settled, and it is determined that the gas turbine has settled when the gas turbine is below a threshold value. The threshold value is obtained from the output of the plant and the capacity of the humidifier 8.

  When the state is stabilized and the gas turbine is settled in step 204, the process proceeds to step 205, where the supply ratio of feed water preheated by the feed water heater 12 to the mixer 29 is set to 0% at this time. Is calculated and output so that the opening degree command Cvb to the feed water heater outlet three-way valve 17 is 100%. As a result, the humidity of the humidified air supplied from the humidifier 8 to the combustor 3 further increases, and the humidity of the compressed air rises to near the rating. At this time, the turbine exhaust temperature and the regeneration heat exchanger outlet exhaust temperature fluctuate due to an increase in humidity, and the humidity of the humidified air from the humidifier 8 fluctuates as the feed water temperature fluctuates. Therefore, the procedure is shifted to the subsequent step 206, and the switching of the operation state of the humidifier 8 is completed after confirming the stabilization of the gas turbine. The static determination in step 206 is the same as in step 204.

  On the other hand, the stop procedure of the humidifier 8 is also performed in the same manner as the startup procedure. That is, when it is determined in step 202 that the humidifier 8 is stopped and the procedure proceeds to step 207, the supply ratio of the supply water from the air cooler 32 to the mixer 29 (at this time, 100%) is 0%. Thus, an opening degree command Cva to the air cooler outlet three-way valve 18 is calculated and output. As a result, the humidity of the humidified air supplied from the humidifier 8 to the combustor 3 is reduced. When the gas turbine is confirmed to be stationary in the following step 208, the process proceeds to step 209, and the supply ratio of the feed water from the feed water heater 12 to the mixer 29 (100% at this time) is set to 0%. Then, the opening degree command Cvb to the feed water heater outlet three-way valve 17 is calculated and output. Thereby, the humidity of the humidified air supplied from the humidifier 8 to the combustor 3 is further reduced. When the stationary state of the gas turbine is confirmed in step 210, the switching of the operation state of the humidifier 8 is finished. The static determination in steps 208 and 210 is the same as in step 204.

FIG. 3 is a graph showing fluctuations in the turbine outlet exhaust temperature Tx when the humidifier 8 is started according to the procedure of FIG.
When the opening degree of the air cooler outlet three-way valve 18 is switched from 0 to 100% (from the blow pipe to the mixer) (step 203 in FIG. 2), the turbine outlet exhaust temperature Tx decreases as the amount of humidification of the compressed air increases. To do. Thereafter, the opening Cvb of the feed water heater outlet three-way valve 17 is switched from 0 to 100% (from the blow pipe to the mixer) (step 205). As the temperature Tx decreases, the temperature of the feed water led from the feed water heater 12 to the mixer 29 decreases, so the mixer outlet temperature Tw of the feed water sprayed by the humidifier 8 also decreases. For this reason, the humidification amount of the compressed air decreases, the turbine outlet exhaust temperature Tx increases, and Tx stabilizes after gradually changing.

  Here, in this embodiment, two systems of a system preheated by the air cooler 32 and a system preheated by the feed water heater 12 are used as systems for supplying the preheated supply water to the humidifier 8. At this time, the amount of heat recovered from the air cooler 32 depends on the temperature of the compressed air from the compressor 2, but the temperature of the compressed air is almost uniquely determined by the rotational speed of the turbine 1 and the discharge pressure of the compressor 2. . Therefore, during the load operation for controlling the gas turbine rotation speed, the heat recovery amount from the air cooler 32 does not vary greatly. Therefore, when the supply water heated by the air cooler 32 is input to the humidifier 8 (step 203), the turbine outlet exhaust temperature Tx and the turbine inlet gas temperature vary depending on the start or stop of humidification of the compressed air. Stable in a short time.

  On the other hand, the amount of heat recovered from the feed water heater 12 depends on the temperature of the exhaust gas at the outlet of the regenerative heat exchanger 11. The exhaust temperature at the outlet of the regenerative heat exchanger 11 includes the amount of heat transferred from the exhaust gas to the humidified air in the regenerative heat exchanger 11, the temperature and humidity of the combustion air flowing into the combustor 3, and the fuel flow rate to the combustor 3. The temperature changes depending on the heat and substance balance values of each part, such as the temperature of the combustion gas flowing into the turbine 1 and the turbine exhaust temperature Tx. Therefore, during load operation, the amount of heat recovered from the feed water heater 12 varies depending on the state of the regenerative heat exchanger 11, the combustor 2, and the turbine 1, and accordingly, the supply water that is supplied to the humidifier 8. Temperature changes. Since the humidification amount of the compressed air at the outlet of the humidifier 8 varies depending on the feed water temperature, the temperature, pressure, and pressure in each part of the turbine 1, the combustor 3, the regenerative heat exchanger 11, the feed water heater 12, and the humidifier 8 are changed. The flow rate fluctuates periodically for a long time, and it takes a long time for the plant operating state to stabilize.

  Therefore, if the order of steps 203 and 205 in FIG. 2 is changed or executed at the same time, the operation state becomes unstable for a long time. As an example, FIG. 4 is a graph showing fluctuations in the turbine outlet exhaust temperature Tx when the steps 203 and 205 in FIG. 2 are switched and the feed water heater 17 is operated before the air cooler 18 when the humidifier 8 is started. It was shown to.

  As shown in FIG. 4, when the feed water heater outlet three-way valve 17 is operated first, the turbine outlet exhaust temperature Tx once decreases with the start of humidification of the compressed air, but thereafter, the feed water mixer outlet temperature Tw. Will begin to rise. The turbine outlet exhaust temperature Tx eventually becomes stable while repeating the increase and decrease in this way, but unlike the overheating in the air cooler 32, the turbine outlet exhaust temperature Tx affects the heating in the feed water heater 12, so the procedure of FIG. Compared with the case of step 203, a long time is required until the operating state is stabilized.

  When the operation state is stabilized after the operation of the feed water heater outlet three-way valve 17, the air cooler outlet three-way valve 18 is operated, but the feed water from the feed water heater 12 has already been led to the mixer 29. Therefore, the heat recovery amount in the feed water heater 12 is changed again. That is, the supply water from the air cooler 32 is supplied to the humidifier 8, so that the humidity of the combustion air increases → the turbine outlet exhaust temperature Tx decreases → the heat recovery by the feed water heater 12 decreases → the humidifier It takes a long time for the gas turbine to reach a steady state by repeating the cycle of the temperature drop of the feed water to 8 → the reduction of the moisture content of the combustion air → the increase of the turbine outlet exhaust temperature Tx. The same applies when the humidification of compressed air is stopped.

FIG. 5 is a graph showing the fluctuation of the turbine outlet exhaust temperature Tx when the air cooler 18 and the feed water heater 17 are operated simultaneously when the humidifier 8 is started, unlike the procedure of FIG.
As shown in FIG. 5, when the three-way valves 17 and 18 are operated at the same time, when the feed water heater 12 is operated, an increase in the amount of water supplied by operating the feed water heater 12 and the air cooler 32 are controlled. The increase in the supply water due to the operation is simultaneously affected by the turbine outlet exhaust temperature Tx. As a result, the amount of humidification of the compressed air rapidly increases and decreases, the cycle fluctuation of the turbine outlet exhaust temperature Tx increases, and a longer time is required until the operating state is stabilized. In addition, since the fluctuation range of the humidification amount of the compressed air becomes larger than necessary, problems such as the turbine exhaust temperature exceeding the rating and reaching the trip temperature or misfiring in the combustor 3 are likely to occur. The same applies when the humidification of compressed air is stopped.

  On the other hand, in the present embodiment, as shown in FIG. 2, first, humidification of compressed air is started by supplying the humidifier 8 with feed water preheated by the air cooler 32 that is not affected by the turbine outlet exhaust temperature Tx. The instability of the operating state at the time is minimized. And even if it starts supply of the feed water preheated with the feed water heater 12 after that, since it is in the state where the turbine exit exhaust temperature fell by addition of the feed water overheated with the air cooler 32, the feed water heater 12 The instability of the operation state accompanying the start of heating of the preheated feed water is also minimized. Moreover, since the feed water preheated by the air cooler 32 and the feed water preheated by the feed water heater 12 are joined together in the mixer 29 in advance, the temperature of the spray water in the humidifier 8 due to the temperature difference between the two. Unevenness does not occur, and a good humidified state of compressed air can be realized. In this way, the humidification amount of the compressed air is adjusted stepwise by supplying the humidifier 8 with the supply water added to the compressed air step by step so that the instability of the operating state is minimized. It is possible to stabilize the operation state at the time of starting and stopping in a short time and improve the followability to the load change.

  Further, when the supply water preheated by the air cooler 32 and the supply water preheated by the feed water heater 12 are merged before being supplied to the humidifier 8, it is possible to temporarily store both in a common tank. However, the space and cost for installing the tank are increased. On the other hand, in this embodiment, the water storage unit 15 of the water recovery device 15 is effectively used, and the feed water preheated by the air cooler 32 and the feed water preheated by the feed water heater 12 are humidified via the mixer 29 when necessary. It was set as the structure which drains to the water collection | recovery apparatus 15 when it supplies to the container 8 and it is not necessary to supply. As a result, the space and cost for installing the tank can be reduced, and the effect of preventing air-cooling of the air cooler 32 and the feed water heater 12 by circulating the feed water can be obtained.

  In addition, as long as the temperature of the water supplied to the humidifier 8 is controlled, for example, a flow rate adjusting valve is provided in a pipe through which the compressed air flows in the air cooler 32, and the air cooler 32 is controlled by controlling the compressed air flow rate. It is also conceivable to adjust the heating amount of the feed water. However, in this case, a pressure loss due to the provision of the flow rate adjusting valve is added, leading to an increase in the pressure loss of the combustion air supplied to the combustor 3. On the other hand, in this embodiment, since the humidification amount of the compressed air is controlled only by the temperature of the water supply to the humidifier 8, the pressure loss of the combustion air is minimized, and a highly efficient system as a whole is constructed. Is possible.

FIG. 6 is a flowchart showing another example of the start / stop procedure of the humidifier 8 by the humidifier controller 101.
In the procedure of FIG. 2, the case where the three-way valves 17 and 18 are switched and controlled has been described. However, the opening degrees of the three-way valves 17 and 18 can be adjusted, and the water supply to the mixer 29 and the water discharge to the water recovery device 15, respectively. The ratio can be adjusted by the opening. The example shown in FIG. 6 is a procedure utilizing such an opening adjustment function of the three-way valves 17 and 18.

  In FIG. 6, steps 301 and 302 are the same as steps 201 and 202 in FIG. When the start mode is determined in step 302, the process proceeds to step 303, and first, the opening Cva of the air cooler outlet three-way valve 18 is set to the intermediate opening x% on the humidifier 8 side (that is, the supply water from the air cooler 32). x% is allowed to flow into the mixer 29), and a part (x%) of the water supplied from the air cooler 32 is supplied to the humidifier 8. Subsequent step 304 is the same as step 204 in FIG. 2, and after confirming that the gas turbine has settled in this step, the procedure proceeds to step 305.

  Step 305 is the same as step 205 in FIG. 2, and the opening degree Cvb of the feed water heater outlet three-way valve 17 is fully opened to the humidifier side (that is, 100% of the feed water from the feed water heater 12 is fed to the mixer 29. Then, the entire amount of water supplied from the feed water heater 12 is supplied to the humidifier 9, and the process proceeds to Step 306.

  In step 306, the opening degree Cva of the air cooler outlet three-way valve 18 is corrected from x% to x '% so that the mixer outlet feed water temperature Tw matches the target value. When the opening degree Cva of the air cooler three-way valve 18 is corrected, in step 307, which is the same as step 304, the stabilization of the gas turbine is confirmed. When the stabilization of the gas turbine is confirmed, the routine proceeds to step 308 where the opening degree Cva of the air cooler outlet three-way valve 18 is fully opened to the humidifier side (that is, 100% of the water supplied from the air cooler 32 is mixed into the mixer). 29) and the humidification start procedure by the humidifier 8 is completed.

  On the other hand, when the stop mode is determined in step 302, the routine proceeds to step 309, where the opening degree Cva of the air cooler outlet three-way valve 18 is changed from 100% of the humidifier side to the intermediate opening degree x% (that is, supplied from the air cooler 32). X% of the water flows into the mixer 29), and a part (x%) of the water supplied from the air cooler 32 is discharged to the blow pipe 26. If it is confirmed in step 310 that is the same as step 304 that the gas turbine has settled, the process proceeds to step 311. Step 311 is the same procedure as Step 209 in FIG. 2, and the opening degree Cvb of the feed water heater outlet three-way valve 17 is fully closed to the humidifier side (that is, 100% of the feed water from the feed water heater 12 is blown). The entire amount of water supplied from the feed water heater 12 is drained to the water recovery device 15.

  In the subsequent step 312, the opening degree Cva of the air cooler outlet three-way valve 18 is corrected from x% to x '% so that the mixer outlet feed water temperature Tw matches the target value, and in the subsequent step 313, the same as step 304 is performed. Check gas turbine stabilization. When the gas turbine is settled, the routine proceeds to step 314, where the opening degree Cva of the air cooler outlet three-way valve 18 is fully closed to the humidifier side (that is, 100% of the water supplied from the air cooler 32 is water). The procedure for stopping the humidification of the compressed air is completed (so that it is drained to the recovery device 15).

  In the control procedure of FIG. 2, when the entire amount of supply water from the feed water heater 12 is poured into the humidifier 8, the turbine outlet exhaust temperature Tx increases with the increase in the humidity of the humidified air at the outlet of the humidifier 8. Fluctuates, and the feed water temperature of the feed water heater 12 fluctuates and the moisture at the outlet of the humidifier 8 fluctuates. On the other hand, in the control procedure of FIG. 6, the mixer outlet water supply temperature Tw is controlled by monitoring the fluctuation of the mixer outlet water supply temperature Tw and adjusting the opening degree of the air cooler outlet three-way valve 18. The moisture fluctuation of the compressed air at the outlet of 8 is suppressed. Thereby, in addition to the effect similar to the control procedure of FIG. 2, the fluctuation | variation of the humidity of the compressed air supplied to the combustor 3 is suppressed more, and starting and stopping of the humidifier 8 can be completed in a shorter time. .

FIG. 7 shows the behavior of the humidifier 8 according to the control procedure of FIG. In this figure, the turbine outlet exhaust temperature Tx, the mixer outlet feed water temperature Tw, and the absolute humidity at the outlet of the humidifier 8 when humidification of compressed air is started by the control procedure of FIG. 6 are shown.
At the time of step 303 (FIG. 6), when the air cooler outlet three-way valve 18 is set to the intermediate opening x%, the mixer outlet feed water temperature Tw matches the feed water temperature at the outlet of the air cooler 32. Further, since humidification in the humidifier 8 is started, the outlet humidity of the humidifier 8 rises and the turbine outlet exhaust temperature Tx falls accordingly.

  Next, the feed water heater outlet three-way valve 17 is switched from the blow pipe 26 side to the mixer 29 side (step 305), and the mixer outlet feed water temperature Tw is controlled by adjusting the opening degree of the air cooler outlet three-way valve 18 (step 305). 306). As a result, the outlet humidity of the humidifier 8 rises and the turbine outlet exhaust temperature Tx also fluctuates in accordance with the humidity change. However, as a result of controlling the mixer outlet feed water temperature Tw substantially constant, the humidity at the outlet of the humidifier 8 is controlled. Transient fluctuations are minimized and the gas turbine settles in a shorter time. Finally, the air cooler outlet three-way valve 18 is completely switched to the mixer 29 side (step 308), and the activation of the humidifier 8 is completed.

  Thus, by performing the control procedure of FIG. 6, the fluctuation | variation of the mixer exit water supply temperature Tw can be suppressed to the minimum, and the operation state at the time of starting of the humidifier 8 can be stabilized in a short time. Can do. The same applies when the humidifier is stopped.

  In the above description, the determination of the gas turbine stabilization and the control of the three-way valves 17 and 18 and the fuel flow rate adjustment valve 6 are executed based on the turbine exhaust temperature Tx and the fuel flow rate command FD. It is also conceivable to use the output, the inlet temperature of the combustor, the compressed air temperature at the outlet of the regeneration heat exchanger 11, the exhaust gas temperature at the outlet of the regeneration heat exchanger 11, and the like.

  Further, in the control procedure of FIG. 6, the opening degree Cva of the air cooler outlet three-way valve 18 is controlled so that the mixer outlet feed water temperature Tw at the start and stop of the humidifier is kept constant. The target temperature TwR may be controlled so that Tw follows TwR as a function of the fuel flow rate command FD or the load request command UD. In this case, a more stable load operation can be achieved by arbitrarily controlling the characteristics of the humidifier 8 when the load changes.

  In the circuit diagram shown in FIG. 1, the three-way valves 17 and 18 are used to adjust the supply ratio to the mixer 29 and the water recovery apparatus 15 heated by the air cooler 32 or the feed water heater 12. Although used, for example, each pipe connected to the mixer 29 and the water recovery device 15 from the air cooler 32 (or the feed water heater 12) is provided with a flow rate adjusting valve, and the same adjustment is made by adjusting the opening of these flow rate adjusting valves. Control may be performed. In this case, the same effect can be obtained.

1 is a circuit diagram illustrating a schematic configuration of a high-humidity gas turbine system according to an embodiment of the present invention. It is a flowchart showing an example of the starting / stopping procedure of the humidifier by the humidifier controller. It is a graph showing the fluctuation | variation of the turbine exit exhaust temperature at the time of starting of the humidifier by the procedure of FIG. It is a graph showing the fluctuation | variation of the turbine exit exhaust temperature at the time of operating a feed water heater before an air cooler at the time of starting of a humidifier. It is a graph showing the fluctuation | variation of the turbine exit exhaust temperature at the time of operating an air cooler and a feed water heater simultaneously at the time of starting of a humidifier. It is a flowchart showing the other example of the starting / stopping procedure of the humidifier by the humidifier controller. It is a figure which shows the behavior of the humidifier by the control procedure of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Turbine 2 Compressor 8 Humidifier 3 Combustor 6 Fuel flow control valve 11 Regenerative heat exchanger 12 Feed water heater 15 Water recovery device 17 Feed water heater outlet three-way valve 18 Air cooler outlet three-way valve 29 Mixer 30 Feed water temperature Detector 31 Exhaust temperature detector 32 Air cooler 100 Gas turbine controller 101 Humidifier controller 102 Fuel flow control valve controller Tw Mixer outlet feed water temperature Tx Turbine outlet exhaust temperature UD Load request command value

Claims (10)

A compressor for compressing air;
A humidifier for humidifying the compressed air compressed by the compressor;
A combustor for burning the compressed air and fuel humidified by the humidifier;
A turbine driven by combustion gas from the combustor;
A regenerative heat exchanger that exchanges heat between the exhaust gas discharged from the turbine and the compressed air supplied from the humidifier to the combustor;
A feed water heater for preheating the feed water added to the compressed air in the humidifier by the exhaust gas that has passed through the regenerative heat exchanger;
An air cooler that preheats the feed water added to the compressed air by the humidifier with the compressed air from the compressor;
A mixer for combining the feed water preheated by the feed water heater and the feed water preheated by the air cooler;
A water recovery device for recovering moisture of exhaust gas that has passed through the feed water heater;
A first control valve capable of changing a rate at which water supplied from the air cooler is led to the mixer and the water recovery device;
A second control valve capable of changing a rate at which feed water from the feed water heater is led to the mixer and the water recovery device;
A high-humidity gas turbine equipment, comprising: a control device that controls the first and second control valves to adjust a humidification amount of the compressed air in the humidifier. The high-humidity gas turbine equipment according to claim 1, wherein the control device includes:
At the start of humidification in the humidifier, the first control valve is controlled to supply water supplied from the air cooler to the mixer, and then the second control valve is controlled to supply water from the feed water heater. Supply water to the mixer,
When humidification is stopped in the humidifier, the first control valve is controlled to drain water supplied from the air cooler to the water recovery device, and then the second control valve is controlled to control the feed water heater. The high-humidity gas turbine equipment is characterized by draining water supplied from the water to the water recovery device.   2. The high-humidity gas turbine facility according to claim 1, further comprising an exhaust temperature detector that detects a temperature of exhaust gas discharged from the turbine, wherein the control device receives a detection signal from the exhaust temperature detector. A high-humidity gas turbine facility that controls the first and second control valves based on a load request command value.   The high-humidity gas turbine equipment according to claim 3, wherein the control device monitors the detection signal of the exhaust temperature detector after controlling the first control valve and after controlling the second control valve. A high-humidity gas turbine facility characterized in that a stationary determination is made and the procedure is shifted or terminated after the stabilization is confirmed. The high-humidity gas turbine equipment according to claim 1, wherein the control device includes:
At the start of humidification in the humidifier, the first control valve is controlled to supply a part of water supplied from the air cooler to the mixer, and then the second control valve is controlled to supply the water supply. Supplying the total amount of water supplied from the heater to the mixer, and further controlling the first control valve to supply the total amount of water supplied from the air cooler to the mixer;
When humidification is stopped in the humidifier, the first control valve is controlled to drain part of the water supplied from the air cooler to the water recovery device, and then the second control valve is controlled to The total amount of water supplied from the feed water heater is drained to the water recovery device, and further, the first control valve is controlled to drain the total amount of water supplied from the air cooler to the water recovery device. High humidity gas turbine equipment.   6. The high-humidity gas turbine equipment according to claim 5, further comprising a feed water temperature detector that detects a temperature of feed water supplied from the mixer to the humidifier, and the control device includes a feed water temperature detector. A high-humidity gas turbine facility characterized by calculating a command signal to the first control valve such that a detection result coincides with a target value.   2. The high-humidity gas turbine equipment according to claim 1, wherein the mixer is a junction of a feed water line from the air cooler and a feed water line from the feed water heater. Turbine equipment. The high-humidity gas turbine equipment according to claim 1,
A fuel flow rate adjustment valve for adjusting the flow rate of fuel supplied to the combustor;
An exhaust temperature detector for detecting the temperature of the exhaust gas discharged from the turbine;
A feed water temperature detector for detecting the temperature of the feed water supplied from the mixer to the humidifier;
A gas turbine control device that calculates a fuel flow rate command value based on a detection signal from the exhaust temperature detector and an input load request command value;
A fuel flow control valve control device that controls the fuel flow control valve in accordance with a fuel flow command value from the gas turbine control device,
The control device that adjusts the humidification amount controls the first and second control valves according to a fuel flow rate command value from the gas turbine control device and a detection signal from the feed water temperature detector, and the humidifier. A high-humidity gas turbine facility, characterized by being a humidifier control device that adjusts the humidification amount of compressed air at the plant.   A compressor that compresses air; a humidifier that humidifies compressed air compressed by the compressor; a combustor that combusts compressed air and fuel humidified by the humidifier; and A turbine driven by combustion gas, a regenerative heat exchanger that exchanges heat between exhaust gas discharged from the turbine and compressed air supplied from the humidifier to the combustor, and the regenerative heat exchanger The feed water heater that preheats the feed water added to the compressed air by the humidifier by the exhaust gas that has passed through, and the feed water that is added to the compressed air by the humidifier by the compressed air from the compressor An air cooler, a mixer for combining the feed water preheated by the feed water heater and the feed water preheated by the air cooler, and water recovery for collecting the moisture content of the exhaust gas that has passed through the feed water heater From the device and the air cooler A first control valve capable of changing a rate at which feed water is led to the mixer and the water recovery device, and a rate at which feed water from the feed water heater is led to the mixer and the water recovery device can be changed. Used in a high-humidity gas turbine facility having a second control valve and an exhaust temperature detector for detecting the temperature of the exhaust gas discharged from the turbine, and controlling the first and second control valves. A control device for adjusting a humidification amount of compressed air in the humidifier. In a control method for a high-humidity gas turbine facility in which compressed air combusted in a gas turbine combustor is humidified by a humidifier,
At the start of humidification of the compressed air in the humidifier, the supply water preheated by the compressed air from the compressor is supplied to the humidifier, and then the supply water preheated by the exhaust gas discharged from the turbine is Join the feed water preheated with compressed air and supply it to the humidifier,
When the humidification of the compressed air is stopped in the humidifier, the supply of water preheated by the compressed air from the compressor is stopped to the humidifier, and then the preheated supply by the exhaust gas discharged from the turbine Stop supplying water to the humidifier,
Thereby, the temperature of the supply water added to compressed air with the said humidifier is adjusted, and the humidification amount of compressed air is adjusted in steps, The control method of the high-humidity gas turbine equipment characterized by the above-mentioned.

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