Intelligent stable combustion control method for thermal power generating unit

Abstract

The invention discloses an intelligent stable combustion control method for a thermal power generating unit, and relates to the technical field of stable combustion control. The method comprises the following steps: monitoring operation parameters of a thermal power generating unit in real time through a sensor group; constructing a gasification efficiency model to evaluate and calculate the energy efficiency of the gasification process in real time; the gasification agent ratio is dynamically controlled through the dynamic load rate and the gasification process energy efficiency; constructing a combustion stability index to quantify the dynamic stability of the combustion process; combustion stability index threshold values are set in a grading mode for grading control. According to the method, the gasification agent proportion is controlled through the gasification process energy efficiency and the dynamic load rate, and the efficiency in the operation process of the thermal power generating unit can be maximized; and meanwhile, dynamic stability of the combustion process is quantified by constructing a combustion stability index, hierarchical control is performed, and stability and safety of operation of the thermal power generating unit are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of stable combustion control, and in particular to an intelligent stable combustion control method for a thermal power unit. Background Art

[0002] With the continuous growth of electricity demand and the gradual evolution of power system structures, the automation control technology of thermal power plants has undergone significant development. Early thermal power plant control focused primarily on stabilizing basic operating parameters, such as maintaining steam pressure, temperature, and unit load within certain limits through simple feedback control loops. With the rise of electronics and computer technology, control systems began to digitize, enabling more precise control algorithms and more complex logical operations. This has enabled thermal power plants to optimize their operation, improving power generation efficiency and safety. To improve the utilization efficiency and environmental performance of low-quality coal, fixed-bed gasification technology has been introduced into thermal power plants. Its core approach involves thermochemically reacting coal with a gasifying agent (oxygen / steam) within a fixed bed to produce a syngas rich in CO and H₂. This syngas, along with partially gasified semi-coke particles, is then fed into the boiler for combustion. This technology offers advantages such as wide fuel adaptability and high carbon conversion rates, making it particularly suitable for high-ash, low-calorific-value coals.

[0003] Current technologies suffer from insufficient coordinated gasification-combustion control and delayed monitoring and control of combustion instability. Traditional gasifiers and boilers operate independently, with fixed gasifier ratios, making them unable to dynamically optimize based on load fluctuations. During variable load conditions, the gasification reaction lags behind boiler demand, exacerbating combustion fluctuations. Existing technologies rely on single parameters (such as oxygen content and main steam pressure) to determine combustion status, lacking multi-dimensional integrated indicators, resulting in a high rate of misjudgment. Control is also crude, employing an on-off adjustment strategy, exacerbating parameter fluctuations.

[0004] For example, the Chinese patent publication number CN120010318A discloses a control system and method for optimizing the performance of a thermal power unit, including: a data acquisition module for collecting various real-time data during the operation of the thermal power unit; a load prediction module for establishing a load prediction model to predict the load change trend by comprehensively considering historical load conditions, load change rate, load change acceleration, and external interference factors; an optimization control module for dynamically adjusting the fuel, damper, and air volume according to the control strategy based on the load prediction results and the unit operation status; corresponding control of the actions of the regulating valve, damper actuator, and water supply regulating valve; a monitoring feedback module for realizing closed-loop control and self-correction; the invention utilizes a load prediction model based on the combination of time series analysis and physical mechanisms and a control strategy that comprehensively considers multi-parameter collaborative optimization to achieve rapid response to load changes, a balance between steam quality and combustion efficiency, adaptive and stable operation under complex working conditions, and overall performance improvement.

[0005] For example, a Chinese patent with authorization announcement number CN118795830B discloses an intelligent control system and method for a power plant based on a thermal power unit, including: a grid feedback module, a compartment separation module, a quality monitoring module, a steam output module and a feeding control module. The grid feedback module is used to evaluate grid demand and calculate boiler gas pressure. The compartment separation module is used to recover exhaust gas and separate the boiler compartment. The quality monitoring module is used to calculate the steam output function and the driving steam volume. The steam output module is used to mix the steam of the two compartments. The feeding control module is used to adjust the fuel feeding rate and the parameters of the steam in the compartment. This invention can optimize the energy consumption of the thermal power unit, improve energy utilization efficiency, enable the generator set to achieve stable and reliable power supply, help improve the power generation efficiency of the thermal power station, and reduce the operating cost of the power station.

[0006] The above patents all have the problems raised by this background technology: the gasification agent ratio is fixed and cannot be dynamically optimized according to load changes; the existing technology relies on a single parameter (such as oxygen content, main steam pressure) to judge the combustion state and lacks multi-dimensional fusion indicators; the combustion control is extensive and cannot be graded according to indicators. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide an intelligent stable combustion control method for a thermal power unit in view of the deficiencies in the prior art.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] An intelligent stable combustion control method for a thermal power unit comprises the following steps:

[0010] Step S1: monitoring the operating parameters of the thermal power unit in real time through a sensor group, wherein the operating parameters of the thermal power unit include: gasifier operating parameters and boiler combustion parameters;

[0011] Step S2: constructing a gasification efficiency model to evaluate and calculate the energy efficiency of the gasification process in real time;

[0012] Step S3, dynamically controlling the gasification agent ratio through the dynamic load rate and the energy efficiency of the gasification process;

[0013] Step S4: constructing a combustion stability index to quantify the dynamic stability of the combustion process;

[0014] Step S5: Setting the combustion stability index threshold in stages to perform staged control.

[0015] Furthermore, the gasifier operating parameters include: synthesis gas mass flow rate, coal mass flow rate into the furnace and average temperature of the oxidation layer;

[0016] The boiler combustion parameters include: furnace temperature, CO reference concentration and furnace pressure.

[0017] Furthermore, the specific formula of the gasification efficiency model is:

[0018]

[0019] in, represents the energy efficiency of the gasification process, and are the syngas mass flow rate and the coal mass flow rate, and Respectively represent the lower calorific value of synthesis gas and the lower calorific value of coal fed into the furnace, represents the temperature correction coefficient, Represents the average temperature of the oxidation layer in fixed bed gasification.

[0020] Furthermore, the dynamic control of the gasification agent ratio through the dynamic load rate and the energy efficiency of the gasification process specifically includes:

[0021] Calculate and adjust the gasifying agent ratio. The specific formula is:

[0022]

[0023] in, Indicates the oxygen / steam ratio in the gasifying agent, represents the optimal oxygen / steam ratio at base load, represents the load correction factor, represents the exponential function with the natural constant e as the base, represents the efficiency feedback gain, represents the target gasification efficiency;

[0024] The specific formula for dynamically adjusting the gasification agent ratio parameters is as follows:

[0025]

[0026] in, Indicates temperature fluctuations over the past minute;

[0027] According to the calculated gasifying agent ratio, adjust the oxygen valve opening and steam flow.

[0028] Furthermore, the combustion stability index is specifically calculated as follows:

[0029]

[0030] in, represents the combustion stability index, represents the standard deviation of furnace cross-section temperature, represents the average temperature of the furnace cross section, Indicates the CO baseline concentration, Indicates the furnace pressure change rate.

[0031] Furthermore, the staged setting of the combustion stability index threshold and the staged triggering control specifically include:

[0032] When the combustion stability index When it is greater than 2 and less than 3.5, the first level of stable combustion control is triggered;

[0033] When the combustion stability index When it is greater than 3.5, the secondary combustion stabilization control is triggered;

[0034] Among them, when the second-level stable combustion control is triggered, the first-level stable combustion control instruction is immediately overwritten to ensure that the emergency control is effective.

[0035] Furthermore, the first-level combustion stabilization control specifically includes:

[0036] Adjust the syngas injection rate. The specific formula is:

[0037]

[0038] in, represents the adjusted syngas injection rate, represents the baseline syngas injection velocity;

[0039] Increase the wall cooling air volume. The specific formula is:

[0040]

[0041] in, Indicates the wall cooling air volume after the increase, Indicates the base wall cooling air volume, where the increased wall cooling air volume .

[0042] Furthermore, the secondary combustion stabilization control specifically includes:

[0043] Stop pulverized coal supply and switch to pure syngas combustion mode;

[0044] Inert gas injection control, the specific formula is;

[0045]

[0046] in, represents the flow rate of inert gas injection, represents the reference inert gas injection flow rate, represents the combustion stabilization gain coefficient, Indicates the maximum furnace temperature;

[0047] Implement graded pressure equalization control in the furnace pressure zone. The specific formula is:

[0048]

[0049] in, represents the target pressure difference of the jth partition, Indicates the reference pressure difference, Indicates the total number of partitions, represents the sine function;

[0050] The burner swing angle is dynamically adjusted based on the real-time temperature field distribution.

[0051] Furthermore, the dynamically adjusting the burner swing angle based on the real-time temperature field distribution specifically includes:

[0052] Step S110, collecting real-time temperature field distribution through an infrared temperature measurement array;

[0053] Step S111, obtaining the actual high temperature zone center coordinates based on the real-time temperature field distribution;

[0054] Step S112, calculating the offset between the actual high temperature zone center and the designed high temperature zone center;

[0055] Step S113: Dynamically adjust the burner swing angle based on the offset.

[0056] Furthermore, the specific formula for calculating the offset between the actual high temperature zone center and the designed high temperature zone center is:

[0057]

[0058] in, represents the coordinates of the actual high temperature zone center, represents the coordinates of the center of the designed high temperature zone, Indicates the offset;

[0059] The burner swing angle is dynamically adjusted based on the offset, and the calculation formula is:

[0060]

[0061] in, represents the burner swing angle adjustment at time t, represents the proportionality coefficient, represents the integral coefficient, represents the offset at time t, Indicates the furnace depth, represents the inverse tangent function, Express 's points.

[0062] Compared with the prior art, the present invention has the following beneficial effects:

[0063] 1. The present invention adopts a coupling mechanism of load rate-driven benchmark ratio and efficiency feedback dynamic correction, which ensures the maximum gasification efficiency while taking into account system safety and response speed.

[0064] 2. The present invention reflects the combustion state through the fusion of multiple parameters, including the standard deviation of the furnace section temperature, the average temperature of the furnace section, the CO baseline concentration, and the furnace pressure change rate. It can quantify the combustion indicators more accurately and avoid the misjudgment of the combustion state by a single indicator.

[0065] 3. The present invention presets thresholds to trigger a hierarchical control strategy, dynamically adjusts combustion parameters to restore stability, and responds in a hierarchical manner, from progressive optimization to emergency intervention, taking into account both efficiency and safety.

[0066] 4. The present invention quantifies the temperature field distribution anomaly into a burner swing angle adjustment instruction through a logic chain of geometric offset → angle conversion → instruction control, thereby reducing the impact of abnormal temperature during the combustion process. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0068] Figure 1 A schematic diagram of a flow chart of an embodiment of the present invention;

[0069] Figure 2 This is a diagram of the combustion stabilization control structure of an embodiment of the present invention;

[0070] Figure 3 This is a flow chart of dynamically adjusting the burner swing angle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0071] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0072] like Figure 1 As shown, a method for intelligent stable combustion control of a thermal power unit includes the following steps:

[0073] Step S1: monitoring the operating parameters of the thermal power unit in real time through a sensor group, wherein the operating parameters of the thermal power unit include: gasifier operating parameters and boiler combustion parameters;

[0074] Step S2: constructing a gasification efficiency model to evaluate and calculate the energy efficiency of the gasification process in real time;

[0075] Step S3, dynamically controlling the gasification agent ratio through the dynamic load rate and the energy efficiency of the gasification process;

[0076] Step S4: constructing a combustion stability index to quantify the dynamic stability of the combustion process;

[0077] Step S5: Setting the combustion stability index threshold in stages to perform staged control.

[0078] The gasifier operating parameters include: synthesis gas mass flow rate, coal mass flow rate and average oxidation layer temperature;

[0079] The boiler combustion parameters include: furnace temperature, CO reference concentration and furnace pressure.

[0080] Syngas mass flow is measured using a thermal mass flowmeter, which is suitable for gas flow measurement, has a fast response, and requires high accuracy. The monitoring indicator is mass flow rate in kg / s, with a sampling frequency of once per second to ensure real-time control and reflect the gasifier's gas production efficiency.

[0081] The mass flow of coal entering the furnace is usually measured by an impulse flow meter, which is suitable for powdered materials. The monitoring indicator is kg / s, and the sampling frequency is slightly lower, once every 5 seconds. The flow of coal powder is relatively stable. The parameters affect the stability and efficiency of the gasification process and must be accurately controlled.

[0082] The average temperature of the oxide layer requires a high-temperature-resistant thermocouple array. The high temperature of the oxide layer requires multiple measurements and averaging. Sampling frequency is once per second to monitor the reaction status in real time. Temperature fluctuations directly affect gasification efficiency and safety.

[0083] The furnace temperature is usually measured by an infrared temperature measurement array, which is non-contact and suitable for high-temperature environments. It monitors the temperature distribution with a sampling frequency of once per second to ensure timely detection of temperature anomalies and reflect the combustion uniformity and stability.

[0084] The CO baseline concentration is measured using a laser gas analyzer, which can quickly and accurately measure gas concentrations with a sampling frequency of once per second. High CO concentrations indicate incomplete combustion, affecting efficiency and environmental performance.

[0085] A high-frequency pressure sensor monitors the furnace pressure's rate of change in kPa / s, sampling 50 times per second. Rapid pressure changes require high-frequency monitoring. Pressure fluctuations reflect combustion stability and help prevent deflagration or flameout.

[0086] The specific formula of the gasification efficiency model is:

[0087]

[0088] in, represents the energy efficiency of the gasification process, and are the syngas mass flow rate and the coal mass flow rate, and Respectively represent the lower calorific value of synthesis gas and the lower calorific value of coal fed into the furnace, represents the temperature correction coefficient, Represents the average temperature of the oxidation layer in fixed bed gasification.

[0089] Reflects the effect of temperature on carbon conversion rate, usually 0.0025.

[0090] is the temperature correction term, which acts as follows:

[0091] when When the temperature is greater than 1250°C, the temperature correction term decreases, indicating that the high temperature leads to a decrease in carbon conversion rate, which needs to be adjusted by the following methods: reducing the oxygen concentration or increasing the steam flow rate.

[0092] The method of dynamically controlling the gasification agent ratio by the dynamic load rate and the energy efficiency of the gasification process specifically includes:

[0093] Calculate and adjust the gasifying agent ratio. The specific formula is:

[0094]

[0095] in, Indicates the oxygen / steam ratio in the gasifying agent, represents the optimal oxygen / steam ratio at base load, represents the load correction factor, represents the exponential function with the natural constant e as the base, represents the efficiency feedback gain, represents the target gasification efficiency;

[0096] The specific formula for dynamically adjusting the gasification agent ratio parameters is as follows:

[0097]

[0098] in, Indicates temperature fluctuations over the past minute;

[0099] According to the calculated gasifying agent ratio, adjust the oxygen valve opening and steam flow.

[0100] in, The optimal oxygen / steam ratio at base load is usually 0.3-0.5;

[0101] Load correction factor , reflecting the sensitivity of load changes to the ratio;

[0102] Efficiency feedback gain , control the dynamic adjustment range;

[0103] Target gasification efficiency Typically set at 88-92%.

[0104] The combustion stability index is specifically calculated as follows:

[0105]

[0106] in, represents the combustion stability index, represents the standard deviation of furnace cross-section temperature, represents the average temperature of the furnace cross section, Indicates the CO baseline concentration, Indicates the furnace pressure change rate.

[0107] in, It represents the temperature fluctuation term, which is a direct indicator of the temperature distribution uniformity and combustion intensity. Indicates the combustion efficiency term, which is a sign of incomplete combustion. Represents the pressure disturbance term, which reflects the pressure fluctuation reflecting the sudden change of combustion rate or air flow turbulence.

[0108] like Figure 2 As shown, the staged setting of the combustion stability index threshold and the staged triggering control specifically include:

[0109] When the combustion stability index When it is greater than 2 and less than 3.5, the first level of stable combustion control is triggered;

[0110] When the combustion stability index When it is greater than 3.5, the secondary combustion stabilization control is triggered;

[0111] Among them, when the second-level stable combustion control is triggered, the first-level stable combustion control instruction is immediately overwritten to ensure that the emergency control is effective.

[0112] Level 1 stable combustion control is characterized by slight combustion instability, requiring active intervention;

[0113] Secondary combustion stabilization control is manifested as severe combustion instability, which may cause deflagration.

[0114] The first-level stable combustion control specifically includes:

[0115] Adjust the synthesis gas injection rate. The specific formula is:

[0116]

[0117] in, represents the adjusted syngas injection rate, represents the baseline syngas injection velocity. This method increases the syngas injection velocity to enhance the turbulent mixing of fuel and air, shorten the ignition delay, and suppress the risk of local flameout. The upper limit of the velocity is 32 m / s to prevent the airflow from scouring the furnace wall.

[0118] Increase the wall cooling air volume. The specific formula is:

[0119]

[0120] in, Indicates the wall cooling air volume after the increase, Indicates the base wall cooling air volume, where the increased wall cooling air volume ,This method enhances wall convection heat transfer, suppresses slagging tendency, and maintains the structural integrity of the burner.

[0121] The secondary combustion stabilization control specifically includes:

[0122] Stop the pulverized coal supply and switch to pure syngas combustion mode to eliminate the lag in semi-coke combustion and quickly stabilize the flame;

[0123] Inert gas injection control, the specific formula is;

[0124]

[0125] in, represents the flow rate of inert gas injection, represents the reference inert gas injection flow rate, represents the combustion stabilization gain coefficient, Indicates the maximum furnace temperature. In the secondary stable combustion mode, nitrogen / CO2 is injected to dilute the combustible gas concentration and reduce the temperature.

[0126] Stable combustion gain coefficient Calibration value 2.0-3.0.

[0127] Implement graded pressure equalization control in the furnace pressure zone. The specific formula is:

[0128]

[0129] in, represents the target pressure difference of the jth partition, Indicates the reference pressure difference, Indicates the total number of partitions, represents a sinusoidal function, implementing differentiated pressure stabilization in the six pressure zones of the furnace (j=1,2,...,6);

[0130] in, For every increase of 1, the pressure difference decreases by about 10%, alleviating the airflow impact;

[0131] The burner swing angle is dynamically adjusted based on the real-time temperature field distribution.

[0132] like Figure 3 As shown, the method of dynamically adjusting the burner swing angle based on the real-time temperature field distribution specifically includes:

[0133] Step S110, collecting real-time temperature field distribution through an infrared temperature measurement array;

[0134] Step S111, obtaining the actual high temperature zone center coordinates based on the real-time temperature field distribution;

[0135] Step S112, calculating the offset between the actual high temperature zone center and the designed high temperature zone center;

[0136] Step S113: Dynamically adjust the burner swing angle based on the offset.

[0137] Temperature field data acquisition process

[0138] Step 1: Spatial Calibration

[0139] Establish the furnace coordinate system: origin: the three-dimensional coordinates of the burner nozzle center (0,0,0), Z axis: along the furnace depth direction (pointing to the rear wall), X / Y axis: furnace width / height direction;

[0140] Sensor coordinate registration: The laser positioning device calibrates the spatial position of each probe (accuracy ±2mm);

[0141] Generate a position matrix.

[0142] Step 2: Temperature data preprocessing

[0143] Time-synchronized filtering: 32-channel data were sampled at 10 Hz and a sliding average filter (window width 5 points) was used.

[0144] Step 3: High temperature zone center coordinate calculation algorithm

[0145] 1. Temperature field grid reconstruction

[0146] Input: 32 discrete temperature and coordinates

[0147] Output: furnace cross-section temperature distribution matrix

[0148] Algorithm: Inverse Distance Weighted Interpolation

[0149] 2. Identification of high temperature areas

[0150] Threshold segmentation:

[0151] Extraction temperature>1200℃ area (combustion core area)

[0152] Connected domain labeling:

[0153] Identify the maximum continuous high temperature area (avoid interference from local hot spots)

[0154] 3. Center coordinate calculation

[0155] The centroid method calculates the center coordinates of the high-temperature zone through the shape rules of the high-temperature zone.

[0156] The specific formula for calculating the offset between the actual high temperature zone center and the designed high temperature zone center is:

[0157]

[0158] in, represents the coordinates of the actual high temperature zone center, represents the coordinates of the center of the designed high temperature zone, Indicates the offset;

[0159] The burner swing angle is dynamically adjusted based on the offset, and the calculation formula is:

[0160]

[0161] in, represents the burner swing angle adjustment at time t, represents the proportionality coefficient, represents the integral coefficient, represents the offset at time t, Indicates the furnace depth, represents the inverse tangent function, Express 's points.

[0162] Proportional coefficient Calibration:

[0163] Step response method: Apply 100mm artificial offset and adjust Make the swing angle reach the target value within 3 seconds;

[0164] Typical values: .

[0165] Integration coefficient Calibration:

[0166] Steady-state error elimination: Under constant load, adjust make Approaches zero within 60 seconds.

[0167] Typical values: (The deeper the furnace, the weaker the integrating effect).

[0168] The swivel rate is limited to less than 5° per second to prevent mechanical overload.

[0169] A 32-point temperature measurement array is arranged along the height of the furnace;

[0170] Use convolutional neural networks (CNN) to identify temperature anomaly areas;

[0171] Dynamically adjust the burner swing angle (±15° range) to make the high temperature zone offset less than 200mm.

[0172] 1. Fixed bed gasifier module

[0173] Feeding system:

[0174] Coal bunker → coal feeder (pulverized coal / lump coal inlet)

[0175] Gasifying agent inlet (oxygen / steam mixing pipe, proportioning valve)

[0176] Reaction layer distribution (from top to bottom):

[0177] Drying layer: coal dehydration area (temperature range: 200-400℃)

[0178] Pyrolysis layer: Volatile analysis area (temperature range: 400-800℃)

[0179] Oxide layer: Carbon and oxygen burn to release heat (temperature range: 1100-1300℃)

[0180] Reduction layer: CO / H2 generation area (temperature range: 800-1000℃)

[0181] Slag discharge system: Rotating grate → ash hopper (slag discharge rate adjustment mechanism)

[0182] Syngas outlet: connected to cyclone separator (separates semi-coke particles, particle size ≤ 200μm)

[0183] 2. Combustion and energy conversion module

[0184] Syngas burner:

[0185] Syngas injection port (speed control valve, 25-35m / s)

[0186] Semi-coke particle inlet (mixed with pulverized coal, mixing ratio 1:3~1:1)

[0187] Boiler body:

[0188] Furnace (infrared temperature measurement array position, 32-point monitoring)

[0189] Water-cooled wall (wall temperature sensor, over-temperature alarm point 600°C)

[0190] Superheater / reheater

[0191] 3. Key sensors and control systems

[0192] Gasifier monitoring points:

[0193] Oxide layer temperature (K-type thermocouple array, 8-point distribution)

[0194] Syngas composition (laser gas analyzer, CO / H2 / CH4 real-time detection)

[0195] Boiler monitoring points:

[0196] Flame temperature field (infrared thermal imager, 10Hz sampling)

[0197] Furnace pressure (high frequency sensor, 50Hz sampling)

[0198] Control actuator:

[0199] Gasifying agent proportioning valve (oxygen / steam dynamic adjustment)

[0200] Burner swing angle servo motor (±15° adjustable)

[0201] Emergency inerting system (nitrogen / CO2 injection nozzle)

[0202] 4. Material flow

[0203] Coal path (coal bunker → gasifier → semi-coke pellets → burner)

[0204] Synthesis gas flow (gasifier → cyclone separator → burner)

[0205] The computer-readable storage medium of this embodiment may be an internal storage unit of the terminal, such as a hard disk or memory of the terminal; the computer-readable storage medium of this embodiment may also be an external storage device of the terminal, such as a plug-in hard disk, a smart memory card, a secure digital card, a flash memory card, etc. equipped on the terminal; further, the computer-readable storage medium may also include both an internal storage unit of the terminal and an external storage device.

[0206] The computer-readable storage medium of this embodiment is used to store computer programs and other programs and data required by the terminal. The computer-readable storage medium can also be used to temporarily store data that has been output or is to be output.

[0207] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented by instructing related hardware through a computer program. The program can be stored in a computer-readable storage medium, and when executed, the program can include the processes in the above-described method embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0208] The examples described in the present invention are merely descriptions of the preferred embodiments of the present invention and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made to the technical solutions of the present invention by engineers and technicians in this field should fall within the scope of protection of the present invention.

Claims

1. An intelligent stable combustion control method for a thermal power unit, characterized in that: The steps include: Step S1: monitoring the operating parameters of the thermal power unit in real time through a sensor group, wherein the operating parameters of the thermal power unit include: gasifier operating parameters and boiler combustion parameters; Step S2: constructing a gasification efficiency model to evaluate and calculate the energy efficiency of the gasification process in real time; Step S3, dynamically controlling the gasification agent ratio through the dynamic load rate and the energy efficiency of the gasification process; Step S4: constructing a combustion stability index to quantify the dynamic stability of the combustion process; Step S5: Setting the combustion stability index threshold in stages to perform staged control.

2. The method according to claim 1, characterized in that The gasifier operating parameters include: synthesis gas mass flow rate, coal mass flow rate and average oxidation layer temperature; The boiler combustion parameters include: furnace temperature, CO reference concentration and furnace pressure.

3. The method according to claim 1, characterized in that The specific formula of the gasification efficiency model is: ； in, represents the energy efficiency of the gasification process, and are the syngas mass flow rate and the coal mass flow rate, and Respectively represent the lower calorific value of synthesis gas and the lower calorific value of coal fed into the furnace, represents the temperature correction coefficient, Represents the average temperature of the oxidation layer in fixed bed gasification.

4. The method according to claim 3, characterized in that The method of dynamically controlling the gasification agent ratio by the dynamic load rate and the energy efficiency of the gasification process specifically includes: Calculate and adjust the gasifying agent ratio. The specific formula is: ； in, Indicates the oxygen / steam ratio in the gasifying agent, represents the optimal oxygen / steam ratio at base load, represents the load correction factor, represents the exponential function with the natural constant e as the base, represents the efficiency feedback gain, represents the target gasification efficiency; The specific formula for dynamically adjusting the gasification agent ratio parameters is as follows: ； in, Indicates temperature fluctuations over the past minute; According to the calculated gasifying agent ratio, adjust the oxygen valve opening and steam flow.

5. The method according to claim 4, characterized in that The combustion stability index is specifically calculated as follows: ； in, represents the combustion stability index, represents the standard deviation of furnace cross-section temperature, represents the average temperature of the furnace cross section, Indicates the CO baseline concentration, Indicates the furnace pressure change rate.

6. The method according to claim 5, characterized in that The step of setting the combustion stability index threshold and performing the step-by-step triggering control specifically includes: When the combustion stability index When it is greater than 2 and less than 3.5, the first level of stable combustion control is triggered; When the combustion stability index When it is greater than 3.5, the secondary combustion stabilization control is triggered; Among them, when the second-level stable combustion control is triggered, the first-level stable combustion control instruction is immediately overwritten to ensure that the emergency control is effective.

7. The method according to claim 6, characterized in that The first-level stable combustion control specifically includes: Adjust the synthesis gas injection rate. The specific formula is: ； in, represents the adjusted syngas injection rate, represents the baseline syngas injection velocity; Increase the wall cooling air volume. The specific formula is: ； in, Indicates the wall cooling air volume after the increase, Indicates the base wall cooling air volume, where the increased wall cooling air volume .

8. The method according to claim 6, characterized in that The secondary combustion stabilization control specifically includes: Stop pulverized coal supply and switch to pure syngas combustion mode; Inert gas injection control, the specific formula is; ； in, represents the flow rate of inert gas injection, represents the reference inert gas injection flow rate, represents the combustion stabilization gain coefficient, Indicates the maximum furnace temperature; Implement graded pressure equalization control in the furnace pressure zone. The specific formula is: ； in, represents the target pressure difference of the jth partition, Indicates the reference pressure difference, Indicates the total number of partitions, represents the sine function; The burner swing angle is dynamically adjusted based on the real-time temperature field distribution.

9. The method according to claim 8, characterized in that The method of dynamically adjusting the burner swing angle based on the real-time temperature field distribution specifically includes: Step S110, collecting real-time temperature field distribution through an infrared temperature measurement array; Step S111, obtaining the actual high temperature zone center coordinates based on the real-time temperature field distribution; Step S112, calculating the offset between the actual high temperature zone center and the designed high temperature zone center; Step S113: Dynamically adjust the burner swing angle based on the offset.

10. The method according to claim 9, characterized in that The specific formula for calculating the offset between the actual high temperature zone center and the designed high temperature zone center is: ； in, represents the coordinates of the actual high temperature zone center, represents the coordinates of the center of the designed high temperature zone, Indicates the offset; The burner swing angle is dynamically adjusted based on the offset, and the calculation formula is: ； in, represents the burner swing angle adjustment at time t, represents the proportionality coefficient, represents the integral coefficient, represents the offset at time t, Indicates the furnace depth, represents the inverse tangent function, Express 's points.

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