Self-adaptive control method for power plant coal gas power generation load when there is no coal gas tank or tank capacity is insufficient
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- KEDA INTELLIGENT IOT TECH CO LTD
- Filing Date
- 2026-03-13
- Publication Date
- 2026-06-19
Smart Images
Figure CN122246781A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of gas-fired boiler technology in power plants, and in particular to an adaptive control method for gas-fired power generation in self-owned power plants to cope with large load fluctuations when there is no gas holder or the gas holder capacity is insufficient. Background Technology
[0002] Boiler gas power generation is a crucial step for steel enterprises to achieve comprehensive energy utilization and improve the recovery and utilization rate of surplus coal gas. By introducing surplus coal gas generated during the production processes of blast furnaces, converters, and coke ovens into self-owned power plant boilers for combustion, high-temperature and high-pressure steam is generated to drive steam turbine generator sets to generate electricity. This not only reduces energy waste and environmental pollution caused by coal gas venting, but also provides enterprises with a stable power supply.
[0003] Currently, most domestic steel companies' self-owned power plants utilize traditional PID control strategies for their gas-fired power generation control systems. Under stable operating conditions, PID control can meet basic production needs, maintaining key parameters such as drum water level, furnace negative pressure, and superheated steam temperature within set ranges. When steel companies are equipped with gas holders, these holders act as buffers and stabilizers, effectively mitigating short-term fluctuations in the gas pipeline network. This allows PID control to cover most of the operating cycle, ensuring the relative stability of the power generation system.
[0004] However, in actual production, two prominent problems exist: First, some steel companies, due to their early construction or incomplete technological upgrades, have not yet been equipped with gas holders, or under specific operating conditions (such as gas pipeline maintenance, gas holder maintenance, or gas holder capacity reaching its limit), they may experience insufficient or zero gas holder capacity. In such cases, the gas pipeline loses its buffering capacity, and fluctuations in gas consumption from upstream production units such as blast furnaces and converters are directly transmitted to the power plant's main gas pipe, causing drastic pressure fluctuations in the main gas pipe within a short period. These pressure fluctuations directly lead to drastic changes in boiler combustion intensity, which in turn results in significant fluctuations in power generation load.
[0005] Secondly, the limitations of traditional PID control become apparent under conditions of drastic load fluctuations. PID controller parameters are typically tuned for stable operating conditions, and their responsiveness to rapid and significant fluctuations is insufficient, easily leading to control lag or overshoot. When load fluctuations exceed the adjustment range of the PID controller, key process parameters such as drum water level, furnace negative pressure, and superheated steam temperature rapidly exceed safety constraints and fail to return to normal ranges for extended periods, triggering equipment alarms and, in severe cases, even threatening production safety. Operators are forced to frequently switch back to manual control mode, relying on human experience for intervention. However, manual response speed is limited, and the system is highly dependent on operator experience, resulting in unstable control effects and easily causing gas waste or equipment damage.
[0006] To address the aforementioned issues, some improvements have been proposed in existing technologies. For example, Chinese patent application publication number CN118980087A discloses a control method for gas-fired boilers in power plants based on machine learning model prediction. This method establishes a predictive model of superheated steam flow to anticipate future flow trends and adjusts each control loop accordingly. While this method improves the predictability of control to some extent, it relies heavily on machine learning models trained on historical data, requiring high data quality and model accuracy. Furthermore, it primarily focuses on efficiency improvements under normal operating conditions and lacks a targeted, tiered response mechanism and abnormal condition handling capabilities for sudden, large-scale load fluctuations when there is no gas holder or insufficient gas holder capacity. In addition, this method does not address emergency control strategies for actuator malfunctions or sensor failures, and its adaptability and robustness under complex real-world conditions need improvement.
[0007] In summary, existing coal gas power generation control technologies suffer from problems such as delayed control response, easy parameter exceedance, strong reliance on manual intervention, and insufficient anomaly response capabilities under special operating conditions such as the absence of a gas holder or insufficient gas holder capacity. They cannot achieve full-cycle adaptive and stable control. There is an urgent need for a comprehensive control method that can predict load fluctuations in advance, provide graded responses, dynamic constraints, and anomaly handling capabilities to cover the full-cycle coal gas power generation control needs under conditions of no gas holder or insufficient gas holder capacity. Summary of the Invention
[0008] The technical problem to be solved by this invention is how to achieve rapid suppression of large fluctuations in power generation load and adaptive handling of abnormal operating conditions when there is no gas holder buffer or insufficient gas holder capacity, resulting in sudden and drastic fluctuations in the pressure of the main gas pipe (rather than predictable flow changes), through hierarchical collaborative control and dynamic constraint mechanisms.
[0009] To address the aforementioned technical problems, this invention provides an adaptive control method for the load of power plant gas-fired power generation when there is no gas holder or the gas holder capacity is insufficient, comprising: Acquire real-time operating data of the gas power generation system. The real-time operating data includes at least the main gas pipeline pressure, gas flow rate, power generation load, and feedback values of multiple water circuit status points and multiple gas circuit status points. Based on the fluctuation amplitude and rate of the main gas pipeline pressure and / or the power generation load, the current operating condition is divided into multiple preset control levels, including stable operation, small fluctuation, and large fluctuation. When the current operating condition is determined to be at a preset large fluctuation level, the hierarchical collaborative control mode is triggered; the following steps are executed under the hierarchical collaborative control mode: (a) Based on the real-time operating data and the preset process experience constraint model, dynamically calculate and correct the control target values of multiple controlled parameters to obtain the corrected target values; (b) Based on the corrected target value, the preliminary output values of multiple actuators are calculated using a preset multivariable coordination controller; (c) A graded control strategy is adopted, and a first-level dynamic constraint is applied to the preliminary output value according to the current gas flow or load value, so as to dynamically constrain the output value of the key actuator within a predetermined graded range that matches the current gas flow or load value, in order to prevent the key process parameters from exceeding the limit. (d) Based on the hardware characteristics of the actuator, apply a second-level dynamic constraint to the output value after the first-level dynamic constraint to limit its output value to a safe operating range; (e) The final output value after two levels of dynamic constraints is sent to the corresponding actuator to control the water circuit and gas circuit of the gas power generation system.
[0010] Furthermore, the large fluctuation level is defined as the percentage threshold at which the fluctuation value of the main gas pipeline pressure exceeds its stable state value within a predetermined time period.
[0011] Furthermore, the first-level dynamic constraints specifically include: For the first-stage desuperheater in the water circuit, based on the current gas flow rate... and the outlet temperature of the first-stage desuperheater Adjust its valve opening The constraints are within the corresponding hierarchical intervals; For the secondary desuperheater in the water circuit, based on the current gas flow rate Secondary desuperheater outlet temperature And the associated overheat protection point temperature, and its valve opening. The constraints are within the corresponding hierarchical intervals; For the hot air valve in the gas circuit, based on the current gas flow rate Adjust its valve opening The constraints are within the corresponding hierarchical intervals.
[0012] Furthermore, when performing graded constraints on the primary or secondary desuperheater valve, if the primary or secondary desuperheater water flow rate is detected to be lower than the preset threshold that should be released by the current valve opening, then coordinated control of the feedwater valve is triggered, adjusting the feedwater valve opening. The system is constrained within a predetermined range and then switched to a control mode primarily based on the feedwater frequency converter to match the feedwater flow rate and the main steam flow rate.
[0013] Furthermore, the second-level dynamic constraints specifically include: Based on the hardware parameters of the actuators, the safe operating range of each actuator is obtained; wherein, the safe operating range includes the minimum safe opening degree and the maximum safe opening degree of the actuator; The output value after the first level of dynamic constraints is limited to between the minimum safe opening and the maximum safe opening.
[0014] Furthermore, the multivariable coordinated controller is constructed based on an improved PID control algorithm, and its control law satisfies the expression:
[0015] In the formula, The output matrix of the actuator. The state deviation matrix is calculated based on the PID method. The input or perturbation matrix is the feedforward input. The state weight matrix is... Let be the feedforward gain matrix, where, , The weight relationships of each element are set based on the physical influence and technological importance of each state point in the water loop during the boiler gas power generation process.
[0016] Furthermore, the actuators involved in the water circuit include a primary desuperheater valve, a secondary desuperheater valve, a main feedwater valve, a reheat desuperheating water valve, and a feedwater frequency converter.
[0017] Furthermore, it also includes generation load boundary control steps: When the power generation load reaches the minimum or maximum power generation, and the adjustment frequency of the forced draft fan or induced draft fan touches the upper or lower limit, the furnace negative pressure and residual oxygen content are controlled by adjusting the opening of the hot air valve. When the power generation load is at its lowest, and the water supply flow fluctuations caused by the main water supply valve and the water supply frequency converter exceed the allowable range, the water supply flow control will be switched from the main valve circuit to the auxiliary circuit.
[0018] Furthermore, it also includes exception handling steps: Identify and handle actuator malfunctions and sensor parameter anomalies; among which: The actuator abnormality handling includes, when it is determined that the actuator has a valve jamming fault, continuously adding an opening compensation value in each subsequent control cycle until the difference between the actuator feedback value and the given value is less than the tolerance value. The sensor anomaly handling includes removing or replacing the abnormal point with a standard value when it is determined that the sensor parameters have been causing the actuator to touch the upper or lower limit of action for a long period of time, and using the reserved alternative point data for control.
[0019] Furthermore, it also includes a step for dynamically adjusting the control frequency: Based on the classification of operating conditions or according to whether abnormal handling is triggered, the frequency of the controller's output is dynamically adjusted: In the event of large fluctuations or abnormal handling conditions, control commands are issued at the highest frequency. Under stable operating conditions, control commands are issued at a second frequency; the first frequency is higher than the second frequency.
[0020] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: This invention employs a tiered control strategy to dynamically classify operating conditions based on real-time operational data and trigger a tiered collaborative control mode under extreme conditions where there is no gas holder or insufficient gas holder capacity leads to sudden and drastic fluctuations in the main gas pipeline pressure. By dynamically correcting the target values of the controlled parameters, calculating the initial output using a multivariable coordinating controller, and applying two levels of dynamic constraints based on the current gas flow rate or load value, this invention achieves rapid suppression and adaptive stable control of large load fluctuations, effectively preventing key process parameters from exceeding limits and improving system operational stability and the ability to cope with abnormal operating conditions. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used 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 those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of a multi-objective control method for gas-fired power generation in a self-owned power plant, as disclosed in an embodiment of the present invention. Figure 2 This is a schematic diagram of the dynamic optimization method for the target value of the present invention; Figure 3 This is a schematic diagram of the controller frequency determination method disclosed in this invention. Detailed Implementation
[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0024] This invention aims to provide a control method for gas-fired power generation in self-owned power plants to cope with large load fluctuations when there is no gas holder or the gas holder capacity is insufficient. Through a tiered control strategy, it achieves rapid response and stable control under conditions of large load fluctuations. The method is described in detail below with reference to the accompanying drawings.
[0025] Step 1: Obtain real-time operating data of the gas power generation system.
[0026] This method first acquires real-time operating data of the gas-fired power generation system. The real-time operating data includes at least the main gas pipe pressure, gas flow rate, power generation load, and feedback values from multiple water circuit status points and multiple gas circuit status points. Specifically: For the water circuit, the collected status points and feedforward points include: inlet temperature of the first-stage desuperheater, outlet temperature of the first-stage desuperheater, and flow rate of the first-stage desuperheater; inlet temperature of the second-stage desuperheater, outlet temperature of the second-stage desuperheater, and flow rate of the second-stage desuperheater; outlet temperature of the reheat desuperheater and outlet steam temperature of the reheater; steam drum water level, steam drum pressure, and inlet pressure of the feedwater inverter; opening degree of the feedwater valve and frequency of the feedwater inverter.
[0027] For the gas circuit, the data collection points include: furnace negative pressure, furnace residual oxygen content; gas flow rate, hot air flow rate; main gas pressure, branch gas pressure; induced draft fan feedback value, forced draft fan feedback value, and hot air valve opening.
[0028] The data acquisition cycle is set to the shortest cycle T1. In this embodiment, T1=2s to ensure a rapid response to load fluctuations.
[0029] Step 2: Divide the current operating conditions into multiple preset control levels.
[0030] Based on the collected gas main pressure and power generation load, the current operating conditions are assessed and classified in real time. In this embodiment, the operating conditions are divided into three preset control levels: stable operation, small fluctuation, and large fluctuation.
[0031] In one embodiment, if the pressure fluctuation of the main gas pipe exceeds 15% of the stable main gas pipe pressure within a time frame of less than 10 seconds, it is determined to be a large fluctuation level. If the large fluctuation threshold is not reached but some fluctuation exists, it is determined to be a small fluctuation level; when the fluctuation amplitude is extremely small or tends to be stable, it is determined to be a stable operation level.
[0032] Step 3: When the current operating condition is determined to be at a high fluctuation level, the graded control strategy is triggered.
[0033] Please see Figure 1 When the current operating condition is determined to be at a high fluctuation level, the hierarchical collaborative multi-objective control module is triggered, which executes the following steps: 3.1 Dynamic target value correction Based on real-time data and data models, combined with on-site process experience, the real-time target values of multiple controlled parameters are dynamically calculated and corrected to obtain the corrected target values.
[0034] like Figure 2 As shown, the correction target values include correction target values for the water circuit and correction target values for the gas circuit. Specifically: The target values for water circuit corrections include: target values for primary desuperheating water outlet, secondary desuperheating water outlet, primary desuperheating water inlet, secondary desuperheating water inlet, reheat desuperheater outlet air temperature, and feedwater inverter outlet pressure.
[0035] The target values for gas circuit correction include: target values for residual oxygen content correction, target values for furnace negative pressure correction, and target values for blast furnace gas main pressure correction.
[0036] The correction method is to calculate the corrected target value based on the baseline target value output by the current data model and combined with the feedforward correction coefficient determined by process experience.
[0037] In a specific example, the target correction value for the outlet temperature of the first-stage desuperheating water is... It can be represented as:
[0038] In the formula, As the baseline target value, The rate of change of pressure in the main gas pipeline. The rate of change of gas flow rate, , This is a correction factor determined based on process experience.
[0039] 3.2 Calculation of preliminary output values by the multivariable coordinated controller Based on the corrected target value obtained in step one, the preliminary output values of multiple actuators are calculated through a preset multivariable coordination controller.
[0040] In this embodiment, the multivariable coordinated controller is constructed based on the design concept of the state weight matrix and disturbance observer in a linear quadratic regulator, and is an improved PID multi-input control system. Its control law is expressed as:
[0041] In the formula, The output matrix of the actuator includes the valve opening OP1s of the first-stage desuperheater, the valve opening OP2s of the second-stage desuperheater, the opening of the main feedwater valve OPv, the opening of the reheat desuperheating water valve OPr, and the frequency of the feedwater inverter Fw, etc. This is the state deviation matrix calculated based on the PID method, which is the deviation between the current value and the target value of each controlled parameter. The input or disturbance matrix is the feedforward input, which includes the main gas pipe pressure, gas flow rate, and main steam flow rate. This is the state weight matrix, used to assign weights to each state deviation; This is the feedforward gain matrix, used to allocate the compensation intensity of the feedforward input.
[0042] Wherein, the state weight matrix With feedforward gain matrix The value needs to be set based on the technological importance and physical influence of each state point in the water circuit on the system operation during the boiler gas power generation process.
[0043] In this embodiment, the weight relationships of each element are set according to the following principles: The inlet temperature deviation of the first-stage desuperheater has the highest weight, followed by the outlet temperature; the inlet and outlet temperature deviations of the second-stage desuperheater have a higher weight than the deviations of the first-stage desuperheater; the steam drum water level and reheater temperature have relatively lower weights. Specific weight values can be adjusted according to boiler characteristics and process requirements.
[0044] 3.3 First-level dynamic constraints This plan adopts a tiered control strategy, based on the current main gas pipeline flow rate. Alternatively, apply a first-level dynamic constraint to the preliminary output value obtained in step 3.2, limiting the output value of the key actuator to a predetermined graded range that matches the current gas flow rate or load value, in order to prevent the key process parameters from exceeding the limits.
[0045] The first-level dynamic constraints specifically include: For the first-stage desuperheater in the water circuit, based on the current gas flow rate... and the outlet temperature of the first-stage desuperheater Adjust its valve opening Constrained within the corresponding graded interval; for the secondary desuperheater in the water circuit, based on the current gas flow rate. And the associated overheat protection point temperature, and its valve opening. The constraints are within the corresponding hierarchical intervals; For the hot air valve in the gas circuit, based on the current gas flow rate Adjust its valve opening The constraints are within the corresponding hierarchical intervals.
[0046] Specifically: For the primary desuperheater valve, based on the main gas pipe flow rate... and the outlet temperature of the first-stage desuperheater Apply hierarchical constraints: when And the outlet temperature of the first-stage desuperheater At that time, the opening degree of the first-stage desuperheater valve Control within the range Inside.
[0047] when and hour, Control within the range Inside.
[0048] And so on, until... and hour, Control within the range Inside.
[0049] For the secondary desuperheater valve, based on the main gas pipe flow rate... The temperature of associated overheat protection points is subject to graded constraints: when And the temperature before the secondary desuperheater Or the temperature after the secondary desuperheater At that time, the opening degree of the secondary desuperheater valve Control within the range Inside.
[0050] when and( or )hour, Control within the range Inside.
[0051] When performing the above-mentioned staged control of the desuperheater valves, it is necessary to supplement it with the coordinated action of the feedwater valves. When the opening degree of the first-stage desuperheater valve... or the opening degree of the secondary desuperheater valve And the flow rate of the first-stage desuperheating water Or secondary desuperheating water flow rate At that time, the opening degree of the water supply valve Constrained to be less than At the same time, the feedwater frequency converter controller is triggered to replace the feedwater valve to match the relationship between the feedwater flow and the main steam flow, that is, the feedwater frequency converter undertakes the main task of feedwater flow regulation.
[0052] For the hot air valve in the gas circuit, based on the main gas pipe flow rate Apply hierarchical constraints: when At that time, the opening degree of the hot air valve Control within the range Inside.
[0053] when hour, Control within the range Inside.
[0054] Furthermore, to prevent the hot air valve from repeatedly oscillating when the gas flow rate fluctuates at the grading threshold boundary, logical judgment conditions are set. and This means that the valve will only be activated if the gas flow rate maintains the same trend over multiple consecutive cycles.
[0055] The gas circuit is also equipped with a feedforward control strategy: under normal conditions, the current feedback value of the induced draft fan is used. For reference, the operating range of the blower is controlled within Internally; when a large fluctuation state is determined, the operating range of the blower is expanded to This is to enhance the system's responsiveness.
[0056] 3.4 Second-level dynamic constraints After the first level of dynamic constraints, a second level of dynamic constraints is applied based on the actuator hardware characteristics. This constraint follows the maximum and minimum safe opening that can be achieved at the beginning of the actuator design, ensuring that the output value does not exceed the physical limits of the actuator.
[0057] In a specific example, for a desuperheater valve, its safe opening range is: The output value after the first level of constraints It needs further revision to .
[0058] 3.5. Send the final output value after two levels of dynamic constraints to the corresponding actuator. The final output value, after undergoing two levels of dynamic constraints, is sent to the corresponding actuator to control the water and gas circuits of the gas-fired power generation system, such as... Figure 3 As shown. The sending frequency is dynamically adjusted according to the operating conditions: under conditions of large fluctuations, the first sending frequency (e.g., once every 2 seconds) is used; under stable conditions, a lower second sending frequency (e.g., once every 10 seconds) is used; and under abnormal handling conditions, a higher frequency (e.g., once every 1 second) is used.
[0059] Step 4: Power Generation Load Boundary Control For special operating conditions where the power generation load reaches its boundary, this method also includes a power generation load boundary control step. Specifically, this includes: When the power generation load reaches the minimum or maximum power generation, and the adjustment frequency of the forced draft fan or induced draft fan touches the upper or lower limit, conventional negative pressure and residual oxygen control methods fail. At this time, the furnace negative pressure and residual oxygen content are adjusted by adding the action of the hot air valve, that is, by changing the opening degree of the hot air valve to change the furnace air volume, thereby indirectly affecting the negative pressure and residual oxygen.
[0060] When the power generation load is at its lowest, and the feedwater flow rate fluctuates significantly due to the control of the main feedwater valve and feedwater frequency converter, the feedwater flow rate control is switched from the main valve circuit to the auxiliary circuit. Specifically, the main feedwater regulating valve is closed, and the auxiliary regulating valve is opened, allowing the auxiliary circuit to handle the feedwater regulation task and reduce fluctuations in the steam drum water level.
[0061] Step 5: Identify and handle actuator malfunctions and sensor parameter anomalies. This method identifies and handles actuator malfunctions and sensor parameter malfunctions.
[0062] For actuator malfunctions, taking valve jamming as an example: when valve jamming is detected, a judgment is made based on the difference between the given value and the feedback value from the previous moment. If the difference is greater than the tolerance value... If this occurs, a valve jamming fault is determined. In this case, a small opening compensation value is continuously added in each subsequent control cycle. The process continues until the difference between the valve feedback value and the given value is less than the tolerance value. When the difference returns to within the tolerance value, the superimposed small opening compensation value is reset to zero.
[0063] For sensor malfunctions: When a sensor parameter consistently causes the actuator to touch its upper or lower operating limits, the sensor is considered malfunctioning. In this case, the malfunctioning point is removed or replaced with a standard value (such as a historical average or empirical value), and control is performed using reserved alternative point data. For example, if the outlet temperature sensor of the first-stage desuperheater is malfunctioning, the inlet temperature of the second-stage desuperheater combined with a correction factor can be used temporarily as a substitute.
[0064] To verify the practical effectiveness of this method, it was applied in a steel company's self-owned power plant. This power plant lacks a gas holder, and the main gas pipeline pressure fluctuates frequently. Before the upgrade, traditional PID control was used, resulting in frequent parameter exceedances during load fluctuations, requiring manual intervention. After applying this method, under conditions of large load fluctuations, the steam drum water level fluctuation range was reduced from ±80mm to ±30mm, and the superheated steam temperature fluctuation range was reduced from ±15℃ to ±5℃, effectively preventing parameter exceedances. Through more precise air-to-coal ratio control, boiler combustion efficiency was improved, and coal consumption was reduced by approximately 2%. In cases of valve jamming or sensor malfunctions, the system can automatically compensate or switch without manual intervention.
[0065] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for adaptive control of power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, characterized in that, include: Acquire real-time operating data of the gas power generation system. The real-time operating data includes at least the main gas pipeline pressure, gas flow rate, power generation load, and feedback values of multiple water circuit status points and multiple gas circuit status points. Based on the fluctuation amplitude and rate of the main gas pipeline pressure and / or the power generation load, the current operating condition is divided into multiple preset control levels, including stable operation, small fluctuation, and large fluctuation. When the current operating condition is determined to be at a preset large fluctuation level, the hierarchical collaborative control mode is triggered; the following steps are executed under the hierarchical collaborative control mode: (a) Based on the real-time operating data and the preset process experience constraint model, dynamically calculate and correct the control target values of multiple controlled parameters to obtain the corrected target values; (b) Based on the corrected target value, the preliminary output values of multiple actuators are calculated using a preset multivariable coordination controller; (c) A graded control strategy is adopted, and a first-level dynamic constraint is applied to the preliminary output value according to the current gas flow or load value, so as to dynamically constrain the output value of the key actuator within a predetermined graded range that matches the current gas flow or load value, in order to prevent the key process parameters from exceeding the limit. (d) Based on the characteristics of the actuator hardware, apply a second level of dynamic constraint to the output value after the first level of dynamic constraint, and limit its output value to a safe operating range; (e) The final output value after two levels of dynamic constraints is sent to the corresponding actuator to control the water circuit and gas circuit of the gas power generation system.
2. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1, is characterized in that... The large fluctuation level is defined as the percentage threshold at which the fluctuation value of the main gas pipeline pressure exceeds its stable state value within a predetermined time period.
3. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1, is characterized in that... The first level of dynamic constraints specifically includes: For the first-stage desuperheater in the water circuit, based on the current gas flow rate... and the outlet temperature of the first-stage desuperheater Adjust its valve opening The constraints are within the corresponding hierarchical intervals; For the secondary desuperheater in the water circuit, based on the current gas flow rate Secondary desuperheater outlet temperature And the associated overheat protection point temperature, and its valve opening. The constraints are within the corresponding hierarchical intervals; For the hot air valve in the gas circuit, based on the current gas flow rate Adjust its valve opening The constraints are within the corresponding hierarchical intervals.
4. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 3, is characterized in that... When performing graded constraints on the primary or secondary desuperheater valves, if the primary or secondary desuperheater water flow rate is detected to be lower than the preset threshold that should be released by the current valve opening, then coordinated control of the feedwater valve is triggered, adjusting the feedwater valve opening. The system is constrained within a predetermined range and then switched to a control mode primarily based on the feedwater frequency converter to match the feedwater flow rate and the main steam flow rate.
5. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1, is characterized in that... The second-level dynamic constraints specifically include: Based on the hardware parameters of the actuators, the safe operating range of each actuator is obtained; wherein, the safe operating range includes the minimum safe opening degree and the maximum safe opening degree of the actuator; The output value after the first level of dynamic constraints is limited to between the minimum safe opening and the maximum safe opening.
6. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1, is characterized in that... The multivariable coordinated controller is constructed based on an improved PID control algorithm, and its control law satisfies the expression: In the formula, The output matrix of the actuator. The state deviation matrix is calculated based on the PID method. The input or perturbation matrix is the feedforward input. The state weight matrix is... Here, is the feedforward gain matrix; where is the state weight matrix corresponding to the water loop. and feedforward gain matrix The weight relationships of each element in the process are set based on the degree of physical influence and technological importance of each state point in the water loop during the boiler gas power generation process.
7. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1, is characterized in that... The actuators involved in the water circuit include a primary desuperheater valve, a secondary desuperheater valve, a main water supply valve, a reheat desuperheating water valve, and a water supply frequency converter.
8. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1, is characterized in that... It also includes generation load boundary control steps: When the power generation load reaches the minimum or maximum power generation, and the adjustment frequency of the forced draft fan or induced draft fan touches the upper or lower limit, the furnace negative pressure and residual oxygen content are controlled by adjusting the opening of the hot air valve. When the power generation load is at its lowest, and the water supply flow fluctuations caused by the main water supply valve and the water supply frequency converter exceed the allowable range, the water supply flow control will be switched from the main valve circuit to the auxiliary circuit.
9. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1, is characterized in that... It also includes exception handling steps: Identify and handle actuator malfunctions and sensor parameter anomalies; among which: The actuator abnormality handling includes, when it is determined that the actuator has a valve jamming fault, continuously adding an opening compensation value in each subsequent control cycle until the difference between the actuator feedback value and the given value is less than the tolerance value. The sensor anomaly handling includes removing or replacing the abnormal point with a standard value when it is determined that the sensor parameters have been causing the actuator to touch the upper or lower limit of action for a long period of time, and using the reserved alternative point data for control.
10. The adaptive control method for power plant gas-fired power generation load when there is no gas holder or the gas holder capacity is insufficient, as described in claim 1 or 9, is characterized in that... It also includes a step for dynamically adjusting the control frequency: Based on the classification of operating conditions or according to whether abnormal handling is triggered, the frequency of the controller's output is dynamically adjusted: In the event of large fluctuations or abnormal handling conditions, control commands are issued at the highest frequency. Under stable operating conditions, control commands are issued at a second frequency; the first frequency is higher than the second frequency.