System and method for controlling temperature in an air intake

Abstract

A system includes a temperature control system (11) configured to be coupled to an intake section (14) of a gas turbine system (10). The temperature control system (11) includes a variable heating system (12) having one or more heaters (28) configured to heat a gas stream in the intake section (14) as the gas stream is cooled by an evaporative cooling system (13, 26). The temperature control system (11) is configured to control the variable heating system (12) to vary an amount of heat supplied by the one or more heaters (28) based on at least one temperature measurement relative to a temperature threshold.

Description

Background Technology

[0001] The subject matter disclosed herein relates to gas turbines, and more specifically, to systems and methods for changing the temperature of air received by the inlet of a gas turbine.

[0002] A gas turbine or gas turbine engine may include an intake section, a compressor section, a combustion section, a turbine section, and an exhaust section. In operation, the intake section receives air from the ambient environment, and the compressor section compresses this air. The compressed air flows to the combustion section, which uses the compressed air to burn one or more fuels to produce hot combustion gases. These hot combustion gases drive the rotation of the turbine section, which in turn drives the compressor section and one or more loads such as a generator.

[0003] The temperature of the air received by the compressor section from the intake section affects the compression of the air and the power output by the gas turbine. For example, lower intake temperature allows the compressor section to supply a larger mass flow of compressed air to the combustion section at a lower temperature, thereby increasing the power output by the gas turbine. However, if the gas turbine generates excessive power due to excessively low intake temperature, adjustments can be made (e.g., partially closing the inlet guide vanes) to reduce the gas turbine's power output. Higher intake temperature causes the compressor section to supply a smaller mass flow of compressed air to the combustion section at a higher temperature, thereby reducing the power output by the gas turbine.

[0004] Therefore, it is necessary to control the intake air temperature in order to control the mass flow of compressed air and the power output of the gas turbine. Summary of the Invention

[0005] The following outlines certain embodiments equivalent to the scope of the originally filed claims. These embodiments are not intended to limit the scope of the invention, but rather are intended only to provide a brief overview of the possible forms of the invention. In practice, the systems and methods of the invention may include various forms that may be similar to or different from the embodiments set forth below.

[0006] In some embodiments, the system includes a temperature control system configured to be coupled to an intake section of a gas turbine system. The temperature control system includes a variable heating system having one or more heaters configured to heat the airflow in the intake section when the airflow is cooled by an evaporative cooling system. The temperature control system is configured to control the variable heating system to vary the heat supplied by the one or more heaters based on at least one temperature measurement relative to a temperature threshold.

[0007] In some embodiments, the method includes controlling a temperature control system to regulate the temperature of the airflow in the inlet section of a gas turbine system. The method also includes controlling an evaporative cooling system to cool the airflow in the inlet section. Furthermore, the method includes controlling a variable heating system having one or more heaters to heat the airflow in the inlet section, wherein controlling the variable heating system includes varying the heat supplied by the one or more heaters based on at least one temperature measurement relative to a temperature threshold.

[0008] In some embodiments, the system includes a temperature control system configured to be coupled to an inlet section of a gas turbine system. The temperature control system includes an evaporative cooling system configured to cool the airflow in the inlet section. The temperature control system also includes a variable heating system having one or more heaters configured to heat the airflow in the inlet section. Furthermore, the temperature control system includes a controller configured to control the variable heating system to vary the heat supplied by the one or more heaters based on at least one temperature measurement relative to a temperature threshold. Attached Figure Description

[0009] These and other features, aspects, and advantages of the invention will be better understood when the following detailed description is read with reference to the accompanying drawings, in which the same reference numerals denote the same parts throughout the drawings, wherein:

[0010] Figure 1 This is a block diagram of an implementation scheme for a gas turbine system with a temperature control system, which includes an evaporative cooling system and a variable heating system.

[0011] Figure 2 yes Figure 1 A diagram illustrating the implementation scheme of the evaporative cooling system for a gas turbine system;

[0012] Figure 3 yes Figure 1 A diagram of an implementation scheme for a variable heating system for a gas turbine; and

[0013] Figure 4 Is using Figures 1 to 3 A flowchart illustrating the implementation scheme for a temperature control system that controls the temperature in the intake section of a gas turbine system. Detailed Implementation

[0014] One or more specific embodiments of the present invention will now be described. To provide a concise description of these embodiments, not all features of the actual implementation may be described in the specification. It should be understood that in the development of any such actual implementation, as in any engineering or design project, many implementation-specific decisions must be made to achieve the developer's specific objectives, such as complying with system-related and business-related constraints, which may vary from implementation to implementation. Furthermore, it should be understood that such development work can be complex and time-consuming, but remains a routine task of design, fabrication, and manufacturing for those skilled in the art who benefit from this disclosure.

[0015] When describing elements of various examples of the invention, the articles “a,” “an,” “the,” and “the” are intended to refer to one or more elements present in the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that additional elements may be present in addition to the listed elements. Furthermore, it should be understood that references to “an example” or “example” in this disclosure are not intended to be construed as excluding the existence of other examples that also include the listed features.

[0016] In the context of this invention, the terms “about” or “approximately” are intended to indicate that the indicated value is not precise and that the actual value may differ from the indicated value without substantially altering the manner in which the relevant operation is performed. For example, as used herein, the terms “about” or “approximately” are intended to convey suitable values ​​within specific tolerances (e.g., ±10%, ±5%, ±1%, and ±0.5%), as will be understood by those skilled in the art.

[0017] As discussed in detail below, the disclosed embodiments include a temperature control system in the intake section upstream of the compressor section of the gas turbine, wherein the temperature control system includes a cooling system (e.g., an evaporative cooling system) and a variable heating system (e.g., one or more heaters). The variable heating system is configured to regulate the temperature when the evaporative cooling system is capable of continuous operation. The evaporative cooling system reduces the temperature of the intake air upstream of the compressor section, thereby contributing to improved efficiency of the compressor section. Specifically, the evaporative cooling system may be configured to reduce the intake air temperature so that the compressor section can supply a larger mass flow of compressed air to the combustion section at a lower temperature, thereby increasing the power output from the gas turbine.

[0018] If the intake air temperature drops to a temperature equal to or below one or more lower temperature thresholds, the temperature control system can selectively enable the variable heating system to counteract the cooling effect by raising the intake air temperature above one or more temperature thresholds. Lower temperature thresholds may include anti-icing temperature thresholds. Anti-icing temperature thresholds may be lower temperature limits that help suppress ice formation, such as temperatures at least above the freezing point. In some embodiments, temperature thresholds may be selected to achieve power output by the gas turbine at a certain level without having to at least partially shut down the compressor's inlet guide vanes (IGV). In some embodiments, temperature thresholds may be selected to reduce emission levels below a threshold.

[0019] An evaporative cooling system can be configured to cool the intake air by mixing it with an evaporative cooling medium, which includes an absorbed cooling liquid (e.g., water). However, the evaporative cooling system can operate in a completely wetted state when in use or completely dry when not in use. That is, in some embodiments, the evaporative cooling system may not have a "partial load" operating point. In embodiments not disclosed, the evaporative cooling system may overcool the intake air.

[0020] There are numerous situations where gas turbine output is limited, and any additional power exceeding that limit cannot be accepted by the grid. In these cases, gas turbine operators typically need to shut down the evaporative cooling system and / or at least partially disable the inlet guide vanes (IGV) of the compressor section. Shutting down the evaporative cooler can result in the unit producing less power than the scheduled output, making this operation not always a viable option. While disabling the IGV allows the gas turbine operator to modulate the unit output to below its limits, it has a significant and detrimental impact on gas turbine efficiency and leads to increased fuel consumption. The disclosed implementation aims to address these drawbacks of conventional evaporative cooling systems.

[0021] Therefore, the disclosed embodiments use a variable heating system to assist the evaporative cooling system, which enables fine control of the temperature of the air received by the intake section to achieve the desired power output. Generally, the variable heating system includes a variable heating controller and one or more variable heaters (e.g., electric heaters, heat exchangers, etc.), which may be located within the intake section, such as near the evaporative cooling system (e.g., upstream, downstream, or in generally overlapping axial positions relative to the evaporative cooling system). In some cases, the variable heating system can be retrofitted into an existing intake section that includes an evaporative cooling system.

[0022] In normal operation, the variable heating controller is configured to generate control signals based on feedback indicating the conditions of the gas turbine and / or ambient air, to cause the one or more heaters to heat the received air. In some embodiments, the variable heating controller may receive feedback from one or more sensors (e.g., temperature sensors, humidity sensors, and pressure sensors, etc.) indicating the conditions (e.g., temperature, humidity, and pressure) of the ambient air or air within various components of the gas turbine (e.g., the temperature of air in the pre-compression compressor, the air flowing into the combustion zone after compression, and the exhaust gas, as discussed in more detail herein). In some embodiments, the feedback may include the operating conditions of the gas turbine, such as the current power output by the gas turbine and the position of the inlet guide vanes (IGV). Furthermore, when the operating parameters of the gas turbine deviate from thresholds (such as the desired power output of the gas turbine), the controller can use the feedback to modify the operation of one or more heaters. In this way, the variable heating system can at least partially automate the control of the temperature of the air received by the gas turbine to achieve the desired power output and efficiency.

[0023] Figure 1 This is a diagram illustrating an embodiment of a gas turbine system 10 with a temperature control system 11 configured to control the temperature of the intake airflow 9 (e.g., airflow) entering the gas turbine system 10. Specifically, the temperature control system 11 includes a variable heating system 12 and a cooling system 13 (e.g., an evaporative cooling system 26), which is disposed along an intake section 14 (e.g., an intake duct) and configured to provide a desired temperature to the intake air 9. In some embodiments, the variable heating system 12 is configured to provide varying amounts of heat to the intake air, while the cooling system 13 (e.g., the evaporative cooling system 26) operates continuously in full operating mode. In other words, the evaporative cooling system 26 can simply be configured to operate in an "on" configuration, while the variable heating system 12 is used to regulate the intake air temperature based on one or more temperature thresholds.

[0024] As discussed in further detail below, the variable heating system 12 may be integrated with and / or separate from the cooling systems 13, 26. For example, the variable heating system 12 may be at least partially or completely contained within the cooling systems 13, 26 (e.g., contained within a common housing 15), or contained upstream of and / or downstream of the cooling systems 13, 26. Furthermore, the variable heating system 12 and / or the cooling systems 13, 26 may be at least partially or completely located within the intake section 14 (e.g., the intake duct).

[0025] In the illustrated embodiment, the gas turbine system 10 includes an intake section 14 with a temperature control system 11, a compressor section 16, a combustion section 18, and a turbine 20. The compressor section 16 may include a plurality of inlet guide vanes (IGVs) 22 arranged downstream of the intake section 14. In at least some cases, such as in land-based gas turbines, the turbine 20 may drive a generator 24. (As opposed to...) Figure 2 In more detail, the intake section 14 includes a cooling system 13 (e.g., an evaporative cooling system 26) to cool the air received by the intake section 14.

[0026] The intake section 14 also includes one or more heaters 28 of the variable heating system 12. These one or more heaters 28 may be located at different positions within the intake section 14, such as in series and / or in parallel with respect to the flow direction through the intake section 14. For example, the one or more heaters 28 may be located at a first axial position 30 upstream of the evaporative cooling system 26, a second axial position 32 at least partially overlapping with the axial position of the evaporative cooling system 26, and / or a third axial position 34 downstream of the evaporative cooling system 26. Figure 3 As discussed in further detail, the approximate axial position of the one or more heaters 28 relative to the evaporative cooling system 26 may have some advantages, such as reducing the likelihood of icing of the IGV 22 and reducing the amount of cooling fluid consumed by the air received by the intake section 14 from the evaporative cooling system 26.

[0027] In operation, intake section 14 receives air from the surrounding environment (e.g., intake 9). As air flows through intake section 14, evaporative cooling system 26 can cool the air, and / or the one or more heaters 28 can heat the air. The cooled and / or heated air then flows through a plurality of IGVs 22 located at the inlet of compressor section 16. Generally, the location of the plurality of IGVs 22 controls the amount of air flowing into compressor section 16, and thus controls the power output by gas turbine 10. Compressor section 16 includes one or more compressor stages (e.g., 1 to 30 compressor stages) that progressively compress the air upstream of combustion section 18.

[0028] Combustion section 18 combusts fuel together with compressed air from compressor section 16 to generate hot combustion gases (or exhaust gases). Combustion section 18 may include one or more burners, such as annular burners or multiple burner canisters arranged circumferentially around the axis of gas turbine 10. Each burner in combustion section 18 includes one or more fuel nozzles 19 that inject fuel into the combustion chamber for combustion. Hot combustion gases (or exhaust gases) flow through turbine section 20 and drive the turbine section to rotate. For example, the hot combustion gases may drive the rotation of one or more turbine stages (e.g., 1 to 5 turbine stages) in turbine section 20. The rotating turbine section 20 then drives one or more loads (such as compressor section 16) and external loads (such as generator 24) to rotate via a common shaft.

[0029] In some embodiments, the operation of the temperature control system 11 (e.g., the variable heating system 12 and cooling systems 13, 26) and / or the gas turbine system 10 may be at least partially controlled by a controller 36 having a processor 38 that can execute instructions stored in memory 40 and / or storage medium 42, or execute instructions based on input provided by a user via input / output (I / O) device 44. Memory 40 and / or storage medium 42 may be read-only memory (ROM), random access memory (RAM), flash memory, optical storage medium, or hard disk drive, to name just a few. For example, in operation, processor 38 may send appropriate control signals to actuate valves of fuel supply system 21 to regulate fuel supply to fuel nozzles 19 in combustion section 18. As another example, processor 38 may send appropriate control signals to control the operation of temperature control system 11 (such as cooling systems 13, 26 and variable heating system 12 (e.g., one or more heaters 28)) to regulate the temperature of intake air 9. For example, the processor 38 can send appropriate control signals to control the operation of the IGV 22 (such as turning the IGV 22 on or off) based on the operation of the gas turbine 10 and the temperature control system 11.

[0030] In some embodiments, controller 36 can be used to regulate the operation of one or more heaters 28, evaporative cooling system 26, and / or IGV 22 based on feedback from an operator (e.g., via I / O device 44) and / or from sensors 46 coupled to intake section 14, compressor section 16, combustion section 18, turbine section 20, and / or generator 24. For example, sensors 46 may include temperature sensors, pressure sensors, humidity sensors, exhaust gas sensors, vibration sensors, gap sensors, flame sensors, or any combination thereof. As another example, sensors 46 in intake section 14 and / or compressor section 16 may monitor the temperature, pressure, and humidity of the airflow 9. Sensors 46 in combustion section 18 may monitor the temperature and pressure of the incoming fuel and air, the temperature and pressure of the combustion gases, and the emission levels of the combustion gases. For example, emissions may include nitrogen oxides (NOx), sulfur oxides (SOx), carbon dioxide (CO2), carbon monoxide (CO), and particulate matter. Similarly, sensor 46 in turbine section 20 can monitor the temperature, pressure, and emission levels of the hot combustion gases, vibrations in turbine section 20, clearances between rotating and stationary components, and the power output by turbine section 20. Sensor 46 coupled to generator 24 can monitor power output, generator 24 temperature, grid stability of the power grid, and other parameters associated with the operation of generator 24. It should be noted that... Figure 1 The location of sensor 46 shown is intended to be exemplary and non-limiting. That is, sensor 46 may be located in one or more of the locations shown, as well as any other location within the gas turbine system 10. Temperature control system 11 may be configured to regulate the temperature of the intake air based on sensor input from any of the sensors 46.

[0031] Figure 2 This is a diagram illustrating an embodiment of an evaporative cooling system 26 having multiple evaporative coolers 27. In some embodiments, the temperature control system 11 may selectively enable or disable one or more of the multiple evaporative coolers 27 to change the cooling capacity of the evaporative cooling system 26. In the illustrated embodiment, each evaporative cooler 27 of the evaporative cooling system 26 includes a fluid tank 48 for storing a cooling fluid (e.g., water) and an evaporative cooling medium 50 for heat exchange between the cooling fluid and the air received by the intake section 14.

[0032] In operation, cooling fluid exits fluid tank 48 via pump suction line 52, which supplies cooling fluid to pump 54. Cooling fluid exits pump 54 via supply line 56, whereby the cooling fluid flows through flow meter 58. As illustrated in the example embodiment, main line 60 and an auxiliary line 62 parallel to main line 60 are located downstream of flow meter 58. Auxiliary line 62 includes orifice plate 64 for regulating the flow rate of cooling fluid exiting supply line 56. Additionally, auxiliary line 62 may include one or more additional valves 66 (e.g., regulating valves). As shown, auxiliary line 62 engages main line 60 at connector 68. However, in other embodiments, evaporative cooling system 26 may not include auxiliary line 62, flow meter 58, and orifice plate 64. In any case, the cooling fluid flow from pump 54 can flow into evaporative cooling medium 50, where the cooling fluid is absorbed by evaporative cooling medium 50, and thus the evaporative cooling medium 50 becomes wetted, as described above. In some embodiments, the collector tray 70 may be positioned downstream of the evaporative cooling medium 50. The collector tray 70 may collect any residual cooling fluid flowing out of the evaporative cooling medium 50 and provide a cooling fluid flow to the drain line 72, which feeds the cooling fluid flow back into the fluid tank 48.

[0033] In some embodiments, each evaporator 27 of the evaporative cooling system 26 may include a plurality of evaporative cooling media 50, wherein each evaporative cooling media 50 has one or more supply lines 56, each supply line being configured to supply cooling fluid from one or more fluid tanks 48. The evaporative cooling media 50 may be arranged in series or in parallel. The evaporative cooling media 50 facilitate evaporative cooling to help cool the intake air 9 in the intake section 14. For example, each evaporator 27 of the evaporative cooling system 26 may include two, three, four, five or more supply lines 56 and evaporative cooling media 50. It should be noted that this embodiment allows the gas turbine system 10 to operate at the desired power output over a wider operating temperature range, such as extremely high and extremely low temperatures. For example, the evaporative cooling system 26 may be configured to selectively enable or disable one or more evaporator coolers 27 and / or one or more evaporative cooling media 50 in each evaporator cooler 27.

[0034] It should be noted that in some implementations, the controller (e.g., as described above relative to...) Figure 1The controller 36 discussed may be used to control the operation of pump 54 and / or flow meter 58. Furthermore, in at least some cases, controller 36 may receive measurements from one or more sensors 46 that provide indications of the operation of the evaporative cooling system 26, such as whether pump 54 is operating and / or the level of cooling fluid in fluid tank 48. Additionally, controller 36 may receive flow measurement values ​​via flow meter 58. In any case, such as relative to… Figure 4 In more detail, controller 36 can use these measurements to control the operation of both cooling systems 13, 26 and variable heating system 12.

[0035] Figure 3 yes Figure 1 A diagram of an embodiment of the variable heating system 12 of the temperature control system 11 further illustrates various heaters 28 configured to heat the air 9 received by the intake section 14. For example, heaters 28 may include a heated fluid injector 74, an electric heater 76, and a heat exchanger 78. Although only one heated fluid injector 74, one electric heater 76, and one heat exchanger 78 are shown, some embodiments of the variable heating system 12 may include any number (e.g., 1, 2, 3, 4, 5, or more) located in... Figure 1 Heated fluid injector 74, electric heater 76 and / or heat exchanger 78 at one or more of the axial positions 30, 32 and / or 34 within the air intake section 14 shown.

[0036] In some embodiments, multiple identical or different heaters 28 (e.g., heated fluid injector 74, electric heater 76, and / or heat exchanger 78) may be arranged in series and / or parallel with respect to the direction of airflow through the intake section 14. If the variable heating system 12 includes, for example... Figure 3 The different heaters 28 (e.g., 74, 76, and / or 78) arranged in series as shown can be arranged in any order. In some embodiments, any one of the heaters 28 (e.g., 74, 76, and / or 78) can be positioned at the first, second, third, fourth, fifth, or subsequent position in the sequence of heaters 28, and any one of the heaters 28 (74, 76, and / or 78) can be positioned at... Figure 1 The axial positions shown are 30, 32 and / or 34. For example, each heater in the heaters 28 (e.g., 74, 76 and / or 78) may be located near the downstream portion 80 of the intake section 14, the upstream portion 82 of the intake section 14, or the intermediate portion 83 of the intake section 14 located between the downstream portion 80 and the upstream portion 82.

[0037] It should be noted that the relative position of one or more heaters 28 (e.g., 74, 76, and / or 78) with respect to the evaporative cooling system 26 can have certain advantages. For example, when one or more heaters 28 are close to the upstream portion 82 (e.g., at axial position 30, which is in a position where...) Figure 1 When positioned upstream of the evaporative cooling system 26 (as shown), the variable heating system 12 allows the IGV 22 to be maintained at the desired power output. However, additional heat (e.g., an increase in the temperature of the airflow 9, thereby reducing relative humidity) can increase the water consumption of the evaporative cooling system 26, potentially reducing efficiency, performance, and / or increasing cost. When one or more heaters 28 are located near the downstream portion 80 (e.g., at axial position 34, where the downstream portion is located in...) Figure 1 When configured downstream of the evaporative cooling system 26, the variable heating system 12 also enables the IGV 22 to be maintained at the desired power output. However, additional heat (e.g., an increase in the temperature of the airflow 9) will not increase the water consumption of the evaporative cooling system 26, as this heat will be added after the evaporative cooling system 26 has cooled the airflow 9.

[0038] The heated fluid injector 74 includes loops 84, each loop being selectively coupled via a corresponding valve 88 to a flow path of a heated fluid 86 (e.g., air, exhaust gas, inert gases such as nitrogen, water such as steam, or any combination thereof). In some embodiments, the heated fluid 86 may include a waste heat source to improve the efficiency of equipment (e.g., a power plant). Waste heat may include, for example, exhaust gas from turbine section 20, a furnace, a boiler, or another combustion system. The heated fluid injector 74 may include one or more fluid nozzles coupled to the wall of intake section 14, a grid of perforated fluid conduits in intake section 14, a grid of fluid conduits having fluid nozzles in intake section 14, or any combination thereof. As used herein, each flow path includes a conduit guiding the heated fluid between components of the variable heating system 12 along a predetermined route.

[0039] Additionally, the heated fluid injector 74 includes a heated fluid outlet 90 that supplies heated fluid 86 to the intake section 14 for mixing with air from the ambient environment, thereby heating the air from the ambient environment. Therefore, by directly injecting the heated fluid 86 into the airflow 9, the heated fluid injector 74 can be considered a direct heating unit. In some embodiments, the variable heating system 12 may include a plurality of heated fluid injectors 74, each including two or more loops in a circuit 84, each loop being configured to inject heated fluid 86 into the intake section 14 to exchange heat between the airflow 9 received by the intake section 14 from the ambient environment and the heated fluid 86. For example, the heated fluid injector 74 may include a circuit 84 (shown in…) Figure 3 Two, three, four, five or more loops in loops 84a, 84b and 84c.

[0040] In some embodiments, the heated fluid 86 may be thermally coupled to a heat source 92 (e.g., an electric heater, a combustion system such as a furnace), which is configured to raise the temperature of the heated fluid 86 in response to a control signal received by the controller 36. For example, the controller 36 may receive feedback via a sensor 46 indicating the ambient temperature of the air in the surrounding environment, and adjust (e.g., increase or decrease) the current output from the heat source 92 to regulate the temperature of the heated fluid 86 based on this feedback. In other embodiments, the heat source 92 may continuously heat the heated fluid 86 and / or maintain the temperature of the heated fluid at a predetermined temperature. Although only one heated fluid injector 74 is shown, it should be noted that, at least in some embodiments, the variable heating system 12 may include multiple heated fluid injectors 74 arranged in series, in parallel, or both.

[0041] During operation, the variable heating system 12 (e.g., controller 36) selectively couples one or more of loops 84a, 84b, and 84c to the heated fluid injector 74 via valves 88a, 88b, and 88c based on operating parameters of the gas turbine system 10 (such as ambient temperature, relative humidity, compressor inlet temperature, power plant output load, gas turbine exhaust temperature, compressor discharge temperature, burner ignition temperature, steam temperature, steam flow, or any combination thereof). For example, controller 36 may receive feedback indicating the temperature of the gas flow 9 via sensor 46 and selectively adjust (e.g., open, partially open, partially closed, or fully closed) the positions of valves 88a, 88b, and / or 88c based on this feedback. In some embodiments, a single valve may be coupled to two or more loops 84a, 84b, and 84c, and thus adjusting the position of valve 88 allows the heated fluid 86 to flow through multiple loops 84. In any case, when one or more of the circuits 84a, 84b and 84c are fluidly coupled to the heated fluid 86 via valves 88a, 88b and 88c, the circuits 84a, 84b and 84c may provide at least a portion of the flow of the heated fluid 86 to the intake section 14 via the heated fluid outlets 90a, 90b and 90c.

[0042] An electric heater 76 (e.g., a heating coil) is electrically coupled to a power source 94. During operation, the power source 94 may supply current to the heating element 77 (e.g., a resistor) of the electric heater 76. The heating element 77 converts the current into heat to raise the temperature of the airflow 9 within the intake section 14. Although only one heated electric heater 76 is shown, it should be noted that, at least in some embodiments, the variable heating system 12 may include multiple electric heaters 76 arranged in series, in parallel, or both.

[0043] The heat exchanger 78 includes loops 84, each loop selectively coupled to a flow path of the heat transfer fluid 96. The heat exchanger 78 may include a shell-and-tube heat exchanger, a plate-and-shell heat exchanger, a plate-fin heat exchanger, a spiral coil heat exchanger, or any suitable heat exchanger for the intake section 14. For example, the heat exchanger may include one or more tubes 79 having fins 81 through which the heat transfer fluid 96 passes, and an airflow 9 passes around the tubes 79 along the fins 81, thereby indirectly transferring heat from the heat transfer fluid 96 to the airflow 9.

[0044] In some embodiments, the variable heating system 12 may include a plurality of heat exchangers 78, each of which includes two or more loops in a loop 84, each loop being configured to exchange heat between a heat transfer fluid 96 in the respective loop and an airflow 9 passing through or across the loop 84. For example, the heat exchangers 78 may include two, three, four, five, or more loops in the loop 84. As shown, the heat exchanger 78 includes three loops 84d, 84e, and 84f, each of which is coupled to a corresponding valve 88d, 88e, and 88f. The heat exchangers 78, one or more loops 84, and the corresponding valves 88 are collectively referred to as the heat exchanger system as part of the variable heating system 12. Additionally, Figure 4 Each loop in the illustrated loop 84 is a single-pass loop, but in other embodiments, one or more loops in loop 84 may be two-pass or multi-pass loops. Although only one heat exchanger 78 is shown, it should be noted that, at least in some embodiments, the variable heating system 12 may include multiple heat exchangers 78 arranged in series, in parallel, or both.

[0045] During operation, the variable heating system 12 (e.g., controller 36) selectively couples one or more of loops 84d, 84e, and 84f to the heat exchanger 78 via valves 88d, 88e, and 88f based on operating parameters of the gas turbine system 10, such as ambient temperature, relative humidity, compressor inlet temperature, power plant output load, gas turbine exhaust temperature, compressor discharge temperature, burner ignition temperature, steam temperature, steam flow, or any combination thereof. For example, controller 36 may receive feedback indicating the temperature of the airflow 9 via sensor 46 and may selectively adjust the positions of valves 88d, 88e, and / or 88f based on this feedback. In some embodiments, at least one of loops 84d, 84e, and 84f may not include valve 88, and thus this at least one loop is an uninterrupted connection of at least one loop 84d, 84e, and 84f that allows the heating fluid to flow continuously through the heat exchanger 78 during operation of the variable heating system 12. In other embodiments, each loop in loop 84 includes a corresponding valve 88. In another embodiment, a single valve 88 can fluidly couple multiple loops 84 to a heat exchanger 78.

[0046] Figure 4 This is shown in the reference above. Figures 1 to 3 The flowchart discussed describes an embodiment of process 98 for operating a temperature control system 11 comprising a variable heating system 12 and cooling systems 13, 26. It should be understood that the steps discussed herein are merely exemplary, and some steps may be omitted or performed in a different order than described below. In some embodiments, process 98 may be stored in memory 40 and / or storage device 42 and executed by processor 38 of controller 36, or stored in other suitable memory and executed by other suitable processing circuitry associated with gas turbine system 10 or by separate suitable processing circuitry.

[0047] like Figure 4As illustrated in the exemplary embodiment, at block 100, processor 38 receives feedback indicating operating parameters of the gas turbine system 10. In the exemplary embodiment, operating parameters may include the temperature of ambient air or the intake air entering intake section 14 and / or entering compressor section 16. For example, air temperature may be measured upstream or downstream of cooling systems 13, 26 and / or IGV 22. Alternatively or additionally, operating parameters may include surface temperatures and / or component temperatures of cooling systems 13, 26 and / or IGV 22. For power enhancement purposes, the aforementioned temperature feedback can be used to help control the intake air temperature. In some embodiments, operating parameters may also include environmental conditions (e.g., relative humidity, ambient temperature, etc.), operating parameters of the gas turbine system 10 (e.g., the position of the inlet guide vanes 22, the discharge temperature or pressure from the compressor section 16, the fuel / air ratio in the combustion section 18, the flame temperature, fuel efficiency or usage, exhaust emission levels, the power output by the gas turbine system 10, the load on the gas turbine system 10, etc.), and / or operating conditions of other related systems such as steam turbines in a combined cycle power plant (e.g., steam temperature, steam pressure, steam flow rate, etc.). Generally, operating parameters can be any parameter indicating the need to regulate the temperature of the intake air entering the intake section 14 of the gas turbine system 10.

[0048] In some embodiments, prior to or at block 100, processor 38 may receive input indicating the desired power output of the gas turbine system. For example, processor 38 may receive feedback indicating ambient temperature and / or relative humidity, temperature thresholds, and / or humidity thresholds of the surrounding environment. Processor 38 may then determine the current power output based on this feedback. For example, memory 40 and / or storage device 42 may store lookup tables and / or lookup graphs that include power outputs based on ambient temperature and / or humidity associated with the surrounding environment and / or components of the gas turbine system 10. In such embodiments, processor 38 may determine whether the current power output of the gas turbine system is higher or lower than the desired power output of the gas turbine system, as generally discussed with respect to block 102.

[0049] In some implementations, lookup tables and / or lookup graphs enable the processor 38 to determine the current power output of the gas turbine system 10 when the evaporative cooling system 26 is active. It should be noted that some evaporative cooling systems may not have a partial load operating point, and therefore, while using the evaporative cooling system 26 (e.g., for power enhancement) to cool ambient air may be advantageous, the evaporative cooling system 26 may overcool the air.

[0050] When processor 38 receives feedback indicating operating parameters, it can compare that feedback with a threshold range, as indicated by box 102. The threshold range can be determined by the operator during the manufacture of the variable heating system 12. Alternatively or additionally, the threshold can be determined through experimental testing and stored in the memory 40 of controller 36. Furthermore, the threshold range can be a threshold value. That is, processor 38 can determine whether the feedback is greater than or less than a threshold value rather than determining a threshold range. As several non-limiting examples, the threshold or threshold range can be a threshold position of the IGV (e.g., maximum or minimum position), a temperature threshold, a humidity threshold, a power output (MW) threshold, etc. Generally, the threshold can be any threshold range or value associated with the performance and / or capacity of the gas turbine system 10, the surrounding environment, or both.

[0051] In some embodiments, processor 38 may compare feedback (e.g., current power output) with a desired power output or a range of desired power output. In an illustrated embodiment, processor 38 may compare feedback (e.g., temperature of ambient air, airflow 9 and / or temperature at cooling systems 13, 26 or IGV 22) with a temperature threshold. For example, a temperature threshold may correspond to a temperature at which the gas turbine system 10 can achieve the desired power output. In some embodiments, process 98 may evaluate feedback (e.g., the measured temperature) against multiple temperature thresholds that may correspond to different locations and / or components (e.g., temperatures at ambient air, cooling systems 12, 26 and IGV 22). Process 98 may also evaluate feedback (e.g., the measured temperature) against multiple temperature thresholds, each of which may trigger a different control action depending on the severity of the temperature.

[0052] At block 104, the processor 38 of controller 36 provides appropriate control signals to cooling system 13 (e.g., evaporative cooling system 26) based on the cooling needs in gas turbine system 10. For example, the processor 38 of controller 36 may selectively control evaporative cooling system 26 to operate when power enhancement is needed (i.e., "on") or to turn off when power enhancement is not needed (i.e., "off"). However, in the illustrated embodiment, the processor 38 of controller 36 may be configured to control evaporative cooling system 26 to operate continuously under normal conditions because variable heating system 12 can be used to regulate the temperature of the gas flow 9 cooled by evaporative cooling system 26.

[0053] At block 106, the processor 38 of controller 36 provides appropriate control signals to the variable heating system 12 to regulate the intake air temperature with or without cooling from the cooling systems 13, 26. For example, in an embodiment where the cooling system 13 (e.g., evaporative cooling system 26) operates continuously during the operation of the gas turbine system 10, the variable heating system 12 can be controlled to regulate the temperature of the intake air cooled by the cooling system 13, for example, by raising the intake air temperature if it drops below one or more temperature thresholds as described above. Therefore, the processor 38 of controller 36 controls the variable heating system 12 by adjusting the heater 28, such as by directing the flow of heat to the injector 74 and / or the valve 88 of the heat exchanger 78 (e.g., as described above relative to...). Figure 3 The processor 38 sends control signals. Alternatively or otherwise, the processor 38 provides appropriate control signals to the power supply 94 electrically coupled to the electric heater 76 to generate heat within the intake section 14. In some embodiments, the controller 36 may provide appropriate signals to a pump coupled to one of the loops in the loop 84 to control the flow rate of the heated fluid 86 or the heat transfer fluid 96 based on feedback.

[0054] In some embodiments, processor 38 may provide appropriate control signals to variable heating system 12 based on the desired power output of gas turbine system 10. That is, processor 38 may determine the supplied heat for using variable heating system 12 to generate the desired power output based on feedback and / or lookup tables or lookup graphs stored in memory 40 and / or storage device 42. In at least some cases, processor 38 may determine the supplied heat based on the presence and / or operation of evaporative cooling system 26. Thus, the variable heating system 12 disclosed in this invention can enable gas turbine system 10 to operate more efficiently by supplying heat to airflow 9 to modify the temperature of airflow 9 to an amount associated with the desired power output, even when operating certain evaporative cooling systems 26 that may overcool air.

[0055] The technical effects of the system and method of the present invention include improving the efficiency and / or power output of the gas turbine system 10 by enabling continuous operation of the cooling system 13 (e.g., evaporative cooling system 26) in the intake section 14, and regulating the intake air temperature via the variable heating system 12 to achieve a target temperature. The target intake air temperature may be a possible minimum temperature based on a lower temperature threshold, or the target temperature may be within a temperature range having an upper temperature threshold and a lower temperature threshold. The target temperature can be selected to achieve the desired power output of the gas turbine system. The target temperature can also be selected to allow the IGV 22 to be maintained in a desired position (e.g., the open position), which would otherwise be impossible if the cooling system 13 overcooled the intake air.

[0056] In some embodiments, the variable heating system 12 may be retrofitted into a gas turbine system 10 with an evaporative cooling system 26, or the variable heating system 12 and the cooling system 13 (e.g., the evaporative cooling system 26) may be co-installed in a new gas turbine system 10. In either case, the variable heating system 12 may regulate (e.g., raise or lower) the temperature of the air cooled by the evaporative cooling system 26 before the air is compressed in the compressor section 16.

[0057] This written description uses examples to disclose the invention, including the best mode, and also enables any person skilled in the art to practice the invention, including making and using any device or system and performing any combined methods. The patentable scope of the invention is defined by the claims and may include other examples that would occur to a person skilled in the art. Such other examples are contemplated within the scope of the claims if they have structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A system comprising: A temperature control system (11) configured to be coupled to the intake section (14) of a gas turbine system (10), wherein the temperature control system (11) includes: A variable heating system (12) having one or more heaters (28) configured to heat the airflow in the intake section (14) when the airflow is cooled by an evaporative cooling system (13, 26), wherein the temperature control system (11) is configured to control the variable heating system (12) to change the heat supplied by the one or more heaters (28) based on at least one temperature measurement relative to a temperature threshold.

2. A system comprising: A temperature control system (11) configured to be coupled to the intake section (14) of a gas turbine system (10), wherein the temperature control system (11) includes: An evaporative cooling system (13, 26) configured to cool the airflow in the intake section (14); and A variable heating system (12) having one or more heaters (28) configured to heat the airflow in the intake section (14) when the airflow is cooled by the evaporative cooling system (13, 26); and A controller configured to control the variable heating system (12) to change the heat supplied by the one or more heaters (28) based on at least one temperature measurement relative to a temperature threshold.

3. The system according to claim 1 or 2, wherein the evaporative cooling system (13, 26) includes one or more evaporative cooling media (50) configured to receive and evaporate cooling liquid.

4. The system according to claim 1 or 2, wherein the one or more heaters (28) are arranged in series, in parallel or in combination thereof.

5. The system according to claim 1 or 2, wherein the one or more heaters (28) are located upstream of the evaporative cooling system (13, 26), downstream of the evaporative cooling system (13, 26), or in a common location or integrated with the evaporative cooling system (13, 26).

6. The system according to claim 1 or 2, wherein the one or more heaters (28) comprise at least one of a fluid injector (74), an electric heater (76), or a heat exchanger (78).

7. The system according to claim 1 or 2, wherein the evaporative cooling system (13, 26) is configured to cool the airflow to increase the power output by the gas turbine system (10).

8. The system according to claim 1 or 2, wherein the variable heating system (12) is configured to heat the airflow to counteract the cooling performed by the evaporative cooling system (13, 26), thereby avoiding shutting down the inlet guide vanes (22) of the compressor section (16) of the gas turbine system (10), reducing the number of inlet guide vanes (22) shut down, or both.

9. The system according to claim 1 or 2, wherein the system includes the intake section (14) having the temperature control system (11).

10. The system according to claim 9, the system comprising the gas turbine system (10) having the intake section (14).

11. A method for controlling a temperature control system (11) to regulate the temperature of an airflow in the intake section (14) of a gas turbine system (10), the method comprising: Control the evaporative cooling system (13, 26) to cool the airflow in the intake section (14); as well as A variable heating system (12) having one or more heaters (28) is controlled to heat the airflow in the intake section (14) when the airflow is cooled by the evaporative cooling system (13, 26), wherein controlling the variable heating system (12) includes changing the heat supplied by the one or more heaters (28) based on at least one temperature measurement relative to a temperature threshold.

12. The method of claim 11, wherein controlling the evaporative cooling system (13, 26) includes cooling the airflow to increase the power output by the gas turbine system (10).

13. The method of claim 12, wherein controlling the variable heating system (12) includes heating the gas flow after the gas flow has been cooled by the evaporative cooling system (13, 26).

14. The method of claim 11, wherein controlling the variable heating system (12) includes changing the heat based on at least one relative humidity measurement relative to a humidity threshold.

15. The method of claim 11, wherein controlling the variable heating system (12) includes heating the airflow to counteract the cooling performed by the evaporative cooling system (13, 26), thereby avoiding shutting down the inlet guide vanes (22) of the compressor section (16) of the gas turbine system (10).

Images