Gas turbine exhaust temperature control method and system

Abstract

The invention discloses a gas turbine exhaust temperature control method and system, and the method comprises the steps: obtaining the inlet and outlet pressure of a gas compressor, calculating the pressure ratio of the gas compressor according to the inlet and outlet pressure, and calculating a turbine exhaust temperature set value through a first function; acquiring a power grid frequency, subtracting the power grid frequency from a fixed frequency to obtain a power grid frequency difference, and calculating initial gas turbine exhaust temperature set value correction according to the power grid frequency difference; the turbine exhaust temperature is obtained, a first fuel flow reference is calculated through a first controller, and a second fuel flow reference is calculated through a second controller; obtaining a third fuel flow reference, comparing the third fuel flow reference with the second fuel flow reference, correcting the temperature control line in combination with the initial gas turbine exhaust temperature set value correction, and taking the smaller value of the third fuel flow reference and the first fuel flow reference as the final fuel flow reference, so that the primary frequency modulation performance of the unit is improved; and frequency modulation economic benefits are brought to the unit, and consumption of renewable energy sources is promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbine control, and in particular to a method and system for controlling turbine exhaust temperature of a gas turbine. Background Art

[0002] At present, the proportion of renewable energy power generation is increasing year by year, but renewable energy power generation is generally intermittent and volatile, and its power generation load is very dependent on environmental conditions, which poses a huge challenge to the stability of the power system. Gas turbines and gas-steam combined cycle power generation methods play a key role in maintaining the stability of the power system with their advantages of clean and environmental protection, fast start and stop, and strong load-changing capacity, and have been rapidly developed. The higher the power generation load of the gas turbine, the higher its power generation efficiency, so the gas turbine unit usually operates in the high-load section. However, as the power generation load of the gas turbine increases, the turbine inlet temperature increases. Due to the limitations of high-temperature component materials, the power generation load of the gas turbine has an upper limit. Since the turbine inlet temperature is too high and difficult to measure, the method of limiting the turbine exhaust temperature is generally adopted to ensure that the turbine inlet temperature is within the allowable range. By adjusting the fuel flow of the gas turbine to control the turbine exhaust temperature within a safe range, it is called a gas turbine turbine exhaust temperature control system, or simply a temperature control system.

[0003] According to the pressure ratio of the compressor, the upper limit value (i.e., set value) of the turbine exhaust temperature is defined at different pressure ratios to form a temperature control line. The turbine exhaust temperature set value is determined according to the compressor pressure ratio under the current working conditions, and the fuel flow reference is solved by the PID controller with the actual gas turbine turbine exhaust temperature. Due to the special control method of the gas turbine, its speed load control system, acceleration control system, startup control system, etc. also adjust the unit parameters through the fuel flow, and the minimum value of the fuel flow reference calculated by each control system is used as the final fuel flow reference to adjust the fuel flow. When running at high load, the fuel flow reference calculated by the speed load control system is generally the smallest. When the gas turbine load continues to increase, the gas turbine turbine exhaust temperature increases accordingly, and the deviation between the exhaust temperature and the temperature set value becomes smaller, until the fuel flow reference calculated by the temperature control system is the smallest and the unit load reaches the highest, which is called the temperature control state. After the unit enters the temperature control state, the unit load can no longer be adjusted freely, and the peak and frequency regulation capabilities are lost. Therefore, the grid dispatcher often controls the load of the gas turbine unit in the high load section without entering the temperature control state, so that the unit's power generation efficiency is maximized while maintaining a certain peak-shaving and frequency regulation capability. Due to the volatility of the grid frequency, a frequency regulation of the speed load control system will cause the calculated fuel flow benchmark to fluctuate up and down. When the unit load is high, the fuel flow benchmarks of the temperature control system and the speed load control system are very close. Due to the ups and downs of the fuel flow benchmark of the speed load control system, the unit switches back and forth between speed load control and temperature control, which greatly affects the unit's frequency regulation performance and cannot meet the specified frequency regulation performance assessment indicators, resulting in economic losses. Summary of the invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a gas turbine turbine exhaust temperature control method and system to solve the problem that the unit switches back and forth between the temperature control state and the speed load control state due to primary frequency regulation, affecting the frequency regulation performance of the unit.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a method for controlling turbine exhaust temperature of a gas turbine, comprising:

[0008] Obtain the inlet and outlet pressures of the compressor, calculate the compressor pressure ratio according to the inlet and outlet pressures, and calculate the turbine exhaust temperature setting value through the first function;

[0009] Obtain the grid frequency, subtract the grid frequency from the fixed frequency to obtain the grid frequency difference, and calculate the correction amount of the initial gas turbine turbine exhaust temperature setting value according to the grid frequency difference;

[0010] Obtaining a turbine exhaust temperature, calculating a first fuel flow rate reference by using a turbine exhaust temperature setting value, an initial gas turbine turbine exhaust temperature setting value correction amount, and the turbine exhaust temperature through a first controller;

[0011] calculating a second fuel flow rate reference by a second controller based on a turbine exhaust temperature set point and a turbine exhaust temperature;

[0012] A third fuel flow reference is obtained, the third fuel flow reference is compared with the second fuel flow reference, and the temperature control line is corrected in combination with the initial gas turbine turbine exhaust temperature setting value correction amount, and the smaller value of the third fuel flow reference and the first fuel flow reference is used as the final fuel flow reference.

[0013] As a preferred embodiment of the gas turbine exhaust gas temperature control method of the present invention, the compressor pressure ratio includes:

[0014] The absolute pressure at the compressor outlet is the compressor outlet gauge pressure plus the atmospheric pressure;

[0015] The compressor inlet pressure is the atmospheric pressure minus the compressor inlet filter pressure difference;

[0016] The compressor pressure ratio is the ratio of the compressor outlet pressure to the compressor inlet pressure.

[0017] As a preferred embodiment of the gas turbine exhaust temperature control method of the present invention, the initial gas turbine exhaust temperature setting value correction amount includes:

[0018] The grid frequency difference is calculated by a second function to obtain a correction value of the initial gas turbine exhaust temperature setting value;

[0019] When the second fuel flow reference is greater than the third fuel flow reference, the comparator output is 0, and the initial gas turbine exhaust temperature setting value correction amount is used as the final gas turbine exhaust temperature setting value correction amount.

[0020] As a preferred solution of the gas turbine exhaust temperature control method of the present invention, the first fuel flow rate reference and the second fuel flow rate reference include:

[0021] The first fuel flow rate reference is obtained by summing the turbine exhaust temperature setting value and the final gas turbine turbine exhaust temperature setting value correction amount and then subtracting the turbine exhaust temperature value, and the first fuel flow rate reference is calculated by the first controller;

[0022] The second fuel flow rate reference is obtained by subtracting the turbine exhaust temperature setting value from the turbine exhaust temperature and calculating the second fuel flow rate reference through the second controller.

[0023] As a preferred embodiment of the gas turbine exhaust gas temperature control method of the present invention, it further comprises:

[0024] When the grid frequency is less than the fixed frequency and exceeds a primary frequency regulation dead zone, the first fuel flow rate reference is increased.

[0025] As a preferred solution of the gas turbine exhaust gas temperature control method of the present invention, the correction of the temperature control line includes:

[0026] As the grid frequency decreases, the final gas turbine exhaust temperature set point correction amount is increased, the first fuel flow reference is increased, and the third fuel flow reference is kept smaller than the first fuel flow reference.

[0027] As a preferred embodiment of the gas turbine exhaust gas temperature control method of the present invention, it further comprises:

[0028] For a conventional gas turbine unit, if the second fuel flow rate reference is less than the third fuel flow rate reference, the gas turbine unit enters a temperature control state;

[0029] For the current gas turbine unit, if the first fuel flow rate reference is less than the third fuel flow rate reference, the gas turbine unit enters the temperature control state;

[0030] The comparison result of the second fuel flow benchmark and the third fuel flow benchmark is retained. When the second fuel flow benchmark has been less than the third fuel flow benchmark for a continuous set time, the exhaust temperature setting value correction amount is changed to 0, the first fuel flow benchmark is reduced to below the third fuel flow benchmark, and the gas turbine unit enters the temperature control state.

[0031] In a second aspect, the present invention provides a gas turbine exhaust temperature control system, comprising:

[0032] A data acquisition module, used for acquiring data required for gas turbine exhaust temperature control;

[0033] A first calculation module, used for calculating the compressor pressure ratio according to the inlet and outlet pressures, and calculating the turbine exhaust temperature setting value through a first function;

[0034] The second calculation module is used to make a difference between the grid frequency and the fixed frequency to obtain a grid frequency difference, and calculate the correction amount of the initial gas turbine turbine exhaust temperature setting value according to the grid frequency difference;

[0035] a third calculation module, for calculating a first fuel flow rate reference by using the turbine exhaust temperature setting value, the initial gas turbine turbine exhaust temperature setting value correction amount, and the turbine exhaust temperature through the first controller;

[0036] a fourth calculation module, configured to calculate a second fuel flow reference through a second controller according to a turbine exhaust temperature set value and a turbine exhaust temperature;

[0037] The correction module is used to compare the third fuel flow reference with the second fuel flow reference, and to correct the temperature control line in combination with the correction amount of the initial gas turbine turbine exhaust temperature setting value, and to use the smaller value of the third fuel flow reference and the first fuel flow reference as the final fuel flow reference.

[0038] In a third aspect, the present invention provides a computing device, comprising:

[0039] Memory and processor;

[0040] The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the gas turbine turbine exhaust temperature control method are implemented.

[0041] In a fourth aspect, the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the gas turbine turbine exhaust temperature control method.

[0042] Compared with the prior art, the present invention has the following beneficial effects: the present invention automatically adjusts the turbine exhaust temperature setting value according to the change of the grid frequency to optimize the primary frequency regulation performance of the gas turbine unit. When the grid frequency drops, by appropriately increasing the turbine exhaust temperature setting value, the fuel flow reference of the temperature control system is increased, thereby avoiding the frequent switching of the unit between the temperature control state and the speed load control state due to the primary frequency regulation, and improving the frequency regulation performance of the unit. When the turbine exhaust temperature is continuously high, the correction of the turbine exhaust temperature setting value can be canceled, so that the unit can enter the temperature control state normally and ensure safe operation. By intelligently adjusting the temperature control line, the frequency regulation performance loss caused by frequent switching of the control mode is reduced, and the frequency regulation economic benefits are generated. On the premise of ensuring the safe operation of the unit, the grid's ability to absorb new energy electricity is improved, and the development and utilization of new energy electricity is promoted. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0044] Figure 1 A schematic diagram of the overall process logic of a gas turbine exhaust gas temperature control method according to an embodiment of the present invention;

[0045] Figure 2 A control logic diagram of a gas turbine exhaust temperature control method according to an embodiment of the present invention;

[0046] Figure 3 This is a function diagram of FX1 in a gas turbine exhaust temperature control method according to an embodiment of the present invention;

[0047] Figure 4 This is a diagram of the FX2 function in a gas turbine exhaust temperature control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0049] Example 1

[0050] Reference Figure 1-Figure 4 , as one embodiment of the present invention, provides a method for controlling the exhaust temperature of a gas turbine, comprising:

[0051] S100: acquiring the inlet and outlet pressures of the compressor, calculating the compressor pressure ratio according to the inlet and outlet pressures, and calculating the turbine exhaust temperature setting value through the first function;

[0052] S200: Acquire the grid frequency, subtract the grid frequency from the fixed frequency to obtain a grid frequency difference, and calculate a correction amount of the initial gas turbine exhaust temperature setting value according to the grid frequency difference;

[0053] S300: Obtaining turbine exhaust temperature, and calculating a first fuel flow rate reference by using a first controller to calculate a turbine exhaust temperature setting value, an initial gas turbine turbine exhaust temperature setting value correction amount, and the turbine exhaust temperature;

[0054] S400: Calculating a second fuel flow rate reference by a second controller according to a turbine exhaust temperature setting value and a turbine exhaust temperature;

[0055] S500: Obtain a third fuel flow reference, compare the third fuel flow reference with the second fuel flow reference, and correct the temperature control line in combination with the initial gas turbine turbine exhaust temperature setting value correction amount, and use the smaller value of the third fuel flow reference and the first fuel flow reference as the final fuel flow reference.

[0056] It should be noted that the present invention corrects the temperature control line according to the grid frequency on the basis of the traditional turbine exhaust temperature control system. When the grid frequency decreases, the unit performs a frequency modulation to increase the fuel flow reference of the speed load control system. The present invention calculates the correction amount of the turbine exhaust temperature setting value according to the grid frequency difference, appropriately raises the temperature control line (i.e., increases the turbine exhaust temperature setting value), and increases the fuel flow reference of the temperature control system accordingly, thereby avoiding the unit switching back and forth between the temperature control state and the speed load control state due to the primary frequency modulation, affecting the frequency modulation performance of the unit. When the fuel flow reference of the traditional temperature control system continues to be the lowest, the adjustment of the temperature control line is cancelled, so that the unit enters the temperature control state normally, ensuring the safe operation of the unit.

[0057] In the embodiment of the present application, the above step S100 includes the following sub-steps A1-A3;

[0058] In A1: The absolute pressure at the compressor outlet is the compressor outlet gauge pressure plus the atmospheric pressure;

[0059] In A2: The compressor inlet pressure is the atmospheric pressure minus the compressor inlet filter pressure difference;

[0060] In A3: The compressor pressure ratio is the ratio of the compressor outlet pressure to the compressor inlet pressure.

[0061] Specifically, Figure 2 As shown, where f is the grid frequency, P CD is the compressor outlet pressure (gauge pressure), P AMB is atmospheric pressure, P CS is the compressor inlet filter pressure difference, T EX is the gas turbine exhaust temperature, U SPEED is the fuel flow rate reference of the speed load control system, f D is the grid frequency difference, P CDA is the compressor outlet pressure (absolute pressure), P CI is the compressor inlet pressure, T COR0 is the correction value of the initial gas turbine exhaust temperature setting, R CP is the compressor pressure ratio, T EXR is the turbine exhaust temperature setting value calculated according to the temperature control line, T COR is the final gas turbine exhaust temperature set point correction, U EXT The final fuel flow rate benchmark for the temperature control system, U EXT0is the fuel flow rate reference calculated by the traditional turbine exhaust temperature control method, U is the final fuel flow rate reference, (1), (2), (3), (8), and (9) are adders and subtractors, (4) represents the function of calculating the initial gas turbine exhaust temperature set point correction value from the grid frequency difference, (5) is a divider; (6) is an analog quantity selection module, (7) is a function of calculating the turbine exhaust temperature set point from the compressor pressure ratio, i.e., the temperature control line, (10) is an ON delay module, (11) and (12) are PID controllers, (13) is a comparator, and (14) is a minimum value selection module.

[0062] The calculated compressor pressure ratio is expressed as:

[0063] P CDA =P CD +P AMB

[0064] P CI =P AMB -P CS

[0065]

[0066] Among them, P CDA is the compressor outlet absolute pressure, P CD is the compressor outlet gauge pressure, P AMB is atmospheric pressure, P CI is the compressor inlet pressure, P CS is the compressor inlet filter pressure difference, R CP is the compressor pressure ratio.

[0067] The turbine exhaust temperature setting value is calculated by the compressor pressure ratio through the function FX1 and is expressed as:

[0068] T EXR =FX1(R CP )

[0069] Among them, T EXR Sets the turbine exhaust temperature.

[0070] Function FX1 is as follows Figure 3 As shown, different gas turbine units have different functional relationships due to their different characteristics.

[0071] In another embodiment, the step function FX1 relationship can also be expressed as:

[0072]

[0073] In the embodiment of the present application, the initial gas turbine exhaust temperature setting value correction amount is calculated according to the grid frequency difference in the above step S200, including the following sub-steps B1-B2:

[0074] In B1: the grid frequency difference is calculated by the second function to obtain the correction value of the initial gas turbine exhaust temperature setting value;

[0075] In B2: when the second fuel flow rate reference is greater than the third fuel flow rate reference, the comparator output is 0, and the initial gas turbine exhaust temperature setting value correction amount is used as the final gas turbine exhaust temperature setting value correction amount.

[0076] Specifically, the grid frequency difference is obtained by subtracting the grid frequency from the fixed frequency of 50 Hz. The correction amount of the initial gas turbine exhaust temperature setting value is calculated by the function FX2 according to the grid frequency difference and is expressed as:

[0077] f D =f-50

[0078] T COR0 =FX2(f D )

[0079] Among them, T COR0 is the correction value for the initial gas turbine exhaust temperature set point.

[0080] Function FX2 is as follows Figure 4 As shown, the functional relationship is determined based on the actual unit characteristics and on-site debugging.

[0081] In another embodiment, the step function FX2 relationship can also be expressed as:

[0082] Define the vector as:

[0083] X=[-0.25,-0.18333,-0.17,-0.15,-0.13,-0.11,-0.09,-0.07,-0.05,-0.0333,0.25]

[0084] Y=[0.3,0.3,0.29,0.27,0.25,0.21,0.16,0.1,0.04,0,0];

[0085] Combining vectors X and Y, the grid frequency difference f D As the independent variable x0, interpolation is used to obtain the initial gas turbine exhaust temperature set point correction value T COR0 .

[0086] For example, when the grid frequency difference f D = -0.14Hz, interpolation gives T COR0 =0.26℃.

[0087] In the embodiment of the present application, the calculation of the first fuel flow rate reference and the calculation of the second fuel flow rate reference in the above steps S300 and S400 include the following sub-steps C1-C2:

[0088] In C1: the first fuel flow rate reference is obtained by summing the turbine exhaust temperature setting value and the final gas turbine turbine exhaust temperature setting value correction amount and then subtracting the turbine exhaust temperature value, and the first fuel flow rate reference is calculated by the first controller;

[0089] In C2: the second fuel flow rate reference is obtained by subtracting the turbine exhaust temperature setting value from the turbine exhaust temperature and calculating the second fuel flow rate reference through the second controller.

[0090] Specifically, the first fuel flow rate reference is the fuel flow rate reference of the temperature control system and is expressed as:

[0091] T COR =T COR0

[0092] U EXT =PID1(T EXR +T COR -T EX )

[0093] Among them, T COR is the final gas turbine exhaust temperature set point correction, PID1(·) is the PID controller, T EXR is the turbine exhaust temperature setting, T EX is the turbine exhaust temperature.

[0094] The second fuel flow rate reference is retained as the fuel flow rate reference calculated by the traditional temperature control system, which is expressed as:

[0095] U EXT0 =PID2(T EXR -T EX )

[0096] Among them, the parameters of PID1(·) and PID2(·) are exactly the same.

[0097] In another embodiment, control methods such as state feedback control and predictive control may also be used.

[0098] In the embodiment of the present application, after completing steps C1-C2, the above steps S300 and S400 may further include:

[0099] In C3: when the grid frequency is less than the fixed frequency and exceeds a frequency regulation dead zone, the first fuel flow rate reference is increased.

[0100] Specifically, when the grid frequency is less than the fixed frequency of 50Hz and exceeds the frequency regulation dead zone of ±0.033Hz, that is, the frequency difference signal is less than -0.033Hz, T COR0 As a positive value, increasing the temperature control system set value can increase the temperature control system fuel flow reference.

[0101] It should be noted that by automatically adjusting the fuel flow rate benchmark, it is possible to quickly respond to changes in grid frequency, avoid switching the unit back and forth between temperature control and speed load control states, improve the primary frequency regulation performance of the unit, and bring economic benefits of frequency regulation; at the same time, when the turbine exhaust temperature continues to be high, the correction of the turbine exhaust temperature set value can be canceled, allowing the unit to enter the temperature control state normally and ensure safe operation.

[0102] In the embodiment of the present application, the temperature control line is corrected according to the comparison result combined with the correction amount of the initial gas turbine exhaust temperature setting value in the above step S500, including the following sub-step D1:

[0103] In D1: while the grid frequency is reduced, the final gas turbine exhaust temperature set point correction amount is increased, the first fuel flow rate reference is increased, and the third fuel flow rate reference is kept smaller than the first fuel flow rate reference;

[0104] Specifically, in a conventional gas turbine control system, due to a decrease in grid frequency, the unit performs a frequency modulation, which increases the third fuel flow reference, i.e., the fuel flow reference of the speed load control system. This often exceeds the fuel flow reference of the conventional temperature control system in an instant and enters a temperature control state, and then becomes less than the fuel flow reference of the conventional temperature control system and returns to a speed load control state.

[0105] This method increases the final gas turbine exhaust temperature setting value correction amount while the grid frequency is reduced, which can increase the fuel flow rate reference of the temperature control system, and always keep the fuel flow rate reference of the speed load control system smaller than the fuel flow rate reference of the temperature control system. The unit is always in the speed load control state, avoiding the unit switching back and forth between the temperature control state and the speed load control state due to a primary frequency modulation;

[0106] As the grid frequency decreases, the fuel flow base of the speed load control system increases, and the initial gas turbine exhaust temperature setting value correction also increases, causing the fuel flow base of the temperature control system to increase accordingly, to ensure that the unit will not switch back and forth between the temperature control state and the speed load control state under various grid frequencies.

[0107] After completing step D1, the above step S500 may further include:

[0108] In D2: for a conventional gas turbine unit, if the second fuel flow rate reference is less than the third fuel flow rate reference, the gas turbine unit enters a temperature control state;

[0109] In D3: for the current gas turbine unit, if the first fuel flow rate reference is less than the third fuel flow rate reference, the gas turbine unit enters the temperature control state;

[0110] In D4: the comparison result of the second fuel flow reference and the third fuel flow reference is retained. When the second fuel flow reference is less than the third fuel flow reference for a continuous set time, the exhaust temperature setting value correction amount is changed to 0, the first fuel flow reference is reduced to below the third fuel flow reference, and the gas turbine unit enters the temperature control state.

[0111] In a preferred embodiment, the delay time length set by the ON delay module can be 3s;

[0112] In another optional implementation, the delay duration set by the ON delay module is determined according to actual unit characteristics and on-site commissioning.

[0113] Specifically, since the temperature control system is crucial to the safe operation of the gas turbine unit, the fuel flow rate benchmark of the traditional temperature control system is retained. When the fuel flow rate benchmark of the traditional temperature control system is less than the fuel flow rate benchmark of the speed load control system, the comparator output is 1, and the unit will enter the temperature control state according to the traditional temperature control system.

[0114] This method keeps the unit in the speed load control state by appropriately raising the temperature control line. When the comparator outputs 1 for 3 consecutive seconds, it means that the unit should indeed enter the temperature control state, the ON delay module outputs 1, and the analog quantity selection module selects 0 as the final gas turbine exhaust temperature set value correction, restoring the traditional temperature control system.

[0115] After the final gas turbine exhaust temperature set point correction amount becomes 0, the fuel flow baseline of the temperature control system quickly decreases to below the fuel flow baseline of the speed load control system, and the unit enters the temperature control state to ensure safe and stable operation. After stabilization, the fuel flow baseline of the temperature control system is the same as the fuel flow baseline calculated by the traditional temperature control system.

[0116] It should be noted that when the grid frequency decreases, by increasing the turbine exhaust temperature set point correction amount and keeping the third fuel flow reference smaller than the first fuel flow reference, the unit is prevented from frequently switching between the temperature control state and the speed load control state, thereby improving the primary frequency regulation performance of the unit and restoring the traditional temperature control system when necessary, thereby ensuring the safe and stable operation of the unit.

[0117] The above is a schematic scheme of a gas turbine turbine exhaust temperature control method of this embodiment. It should be noted that the technical scheme of the gas turbine turbine exhaust temperature control system and the technical scheme of the gas turbine turbine exhaust temperature control method described above belong to the same concept, and the details of the technical scheme of the gas turbine turbine exhaust temperature control system not described in detail in this embodiment can all be referred to the description of the technical scheme of the gas turbine turbine exhaust temperature control method described above.

[0118] The gas turbine exhaust temperature control system in this embodiment includes:

[0119] A data acquisition module, used for acquiring data required for gas turbine exhaust temperature control;

[0120] A first calculation module, used for calculating the compressor pressure ratio according to the inlet and outlet pressures, and calculating the turbine exhaust temperature setting value through a first function;

[0121] The second calculation module is used to make a difference between the grid frequency and the fixed frequency to obtain a grid frequency difference, and calculate the correction amount of the initial gas turbine turbine exhaust temperature setting value according to the grid frequency difference;

[0122] a third calculation module, for calculating a first fuel flow rate reference by using the turbine exhaust temperature setting value, the initial gas turbine turbine exhaust temperature setting value correction amount, and the turbine exhaust temperature through the first controller;

[0123] a fourth calculation module, configured to calculate a second fuel flow reference through a second controller according to a turbine exhaust temperature set value and a turbine exhaust temperature;

[0124] The correction module is used to compare the third fuel flow reference with the second fuel flow reference, and to correct the temperature control line in combination with the correction amount of the initial gas turbine turbine exhaust temperature setting value, and to use the smaller value of the third fuel flow reference and the first fuel flow reference as the final fuel flow reference.

[0125] This embodiment further provides a computing device, which is applicable to the case of gas turbine exhaust temperature control, and includes:

[0126] Memory and processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement the gas turbine turbine exhaust temperature control method proposed in the above embodiment.

[0127] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method for controlling the turbine exhaust temperature of a gas turbine as proposed in the above embodiment is implemented.

[0128] The storage medium proposed in this embodiment and the method for implementing gas turbine turbine exhaust temperature control proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0129] Through the above description of the implementation methods, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course can also be implemented by hardware. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ReadOnly, Memory, ROM), random access memory (Random Access Memory, RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform the methods of various embodiments of the present invention.

[0130] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for controlling the exhaust temperature of a gas turbine, characterized in that: include: Obtain the inlet and outlet pressures of the compressor, calculate the compressor pressure ratio according to the inlet and outlet pressures, and calculate the turbine exhaust temperature setting value through the first function; Obtain the grid frequency, subtract the grid frequency from the fixed frequency to obtain the grid frequency difference, and calculate the correction amount of the initial gas turbine turbine exhaust temperature setting value according to the grid frequency difference; Obtaining a turbine exhaust temperature, calculating a first fuel flow rate reference by using a turbine exhaust temperature setting value, an initial gas turbine turbine exhaust temperature setting value correction amount, and the turbine exhaust temperature through a first controller; calculating a second fuel flow rate reference by a second controller based on a turbine exhaust temperature set point and a turbine exhaust temperature; A third fuel flow reference is obtained, the third fuel flow reference is compared with the second fuel flow reference, and the temperature control line is corrected in combination with the initial gas turbine turbine exhaust temperature setting value correction amount, and the smaller value of the third fuel flow reference and the first fuel flow reference is used as the final fuel flow reference.

2. The gas turbine exhaust gas temperature control method according to claim 1, characterized in that: The compressor pressure ratio includes: The absolute pressure at the compressor outlet is the compressor outlet gauge pressure plus the atmospheric pressure; The compressor inlet pressure is the atmospheric pressure minus the compressor inlet filter pressure difference; The compressor pressure ratio is the ratio of the compressor outlet pressure to the compressor inlet pressure.

3. The gas turbine exhaust gas temperature control method according to claim 2, characterized in that: The initial gas turbine exhaust temperature set point correction includes: The grid frequency difference is calculated by a second function to obtain a correction value of the initial gas turbine exhaust temperature setting value; When the second fuel flow reference is greater than the third fuel flow reference, the comparator output is 0, and the initial gas turbine exhaust temperature setting value correction amount is used as the final gas turbine exhaust temperature setting value correction amount.

4. The gas turbine exhaust gas temperature control method according to claim 3, characterized in that: The first fuel flow rate reference and the second fuel flow rate reference include: The first fuel flow rate reference is obtained by summing the turbine exhaust temperature setting value and the final gas turbine turbine exhaust temperature setting value correction amount and then subtracting the turbine exhaust temperature value, and the first fuel flow rate reference is calculated by the first controller; The second fuel flow rate reference is obtained by subtracting the turbine exhaust temperature setting value from the turbine exhaust temperature and calculating the second fuel flow rate reference through the second controller.

5. The gas turbine exhaust gas temperature control method according to claim 4, characterized in that: Also includes: When the grid frequency is less than the fixed frequency and exceeds a primary frequency regulation dead zone, the first fuel flow rate reference is increased.

6. The gas turbine exhaust gas temperature control method according to claim 3 or 5, characterized in that: Correction of the temperature control line includes: As the grid frequency decreases, the final gas turbine exhaust temperature set point correction amount is increased, the first fuel flow reference is increased, and the third fuel flow reference is kept smaller than the first fuel flow reference.

7. The gas turbine exhaust gas temperature control method according to claim 6, characterized in that: Also includes: For a conventional gas turbine unit, if the second fuel flow rate reference is less than the third fuel flow rate reference, the gas turbine unit enters a temperature control state; For the current gas turbine unit, if the first fuel flow rate reference is less than the third fuel flow rate reference, the gas turbine unit enters the temperature control state; The comparison result of the second fuel flow benchmark and the third fuel flow benchmark is retained. When the second fuel flow benchmark has been less than the third fuel flow benchmark for a continuous set time, the exhaust temperature setting value correction amount is changed to 0, the first fuel flow benchmark is reduced to below the third fuel flow benchmark, and the gas turbine unit enters the temperature control state.

8. A system using the gas turbine exhaust gas temperature control method according to any one of claims 1 to 7, characterized in that: include: A data acquisition module, used for acquiring data required for gas turbine exhaust temperature control; A first calculation module, used for calculating the compressor pressure ratio according to the inlet and outlet pressures, and calculating the turbine exhaust temperature setting value through a first function; The second calculation module is used to make a difference between the grid frequency and the fixed frequency to obtain a grid frequency difference, and calculate the correction amount of the initial gas turbine turbine exhaust temperature setting value according to the grid frequency difference; a third calculation module, for calculating a first fuel flow rate reference by using the turbine exhaust temperature setting value, the initial gas turbine turbine exhaust temperature setting value correction amount, and the turbine exhaust temperature through the first controller; a fourth calculation module, configured to calculate a second fuel flow reference through a second controller according to a turbine exhaust temperature setting value and a turbine exhaust temperature; The correction module is used to compare the third fuel flow reference with the second fuel flow reference, and to correct the temperature control line in combination with the correction amount of the initial gas turbine turbine exhaust temperature setting value, and to use the smaller value of the third fuel flow reference and the first fuel flow reference as the final fuel flow reference.

9. An electronic device, comprising: Memory and processor; The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the gas turbine turbine exhaust temperature control method described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the gas turbine exhaust temperature control method according to any one of claims 1 to 7.

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