Adaptive regulation method and system for steam boilers under various operating conditions

Abstract

This invention relates to the field of intelligent control technology for steam boilers, specifically to an adaptive adjustment method and system for steam boilers under various operating conditions. Addressing the problems of inaccurate condition judgment and uncoordinated adjustment in existing boilers under conditions such as load increase, load decrease, sudden load changes, and fuel fluctuations, due to lag effects, volume distortion, and heat storage / release effects, the method includes: collecting operating parameters and actuator action parameters to determine the current operating condition; constructing storage areas for the effects of heating lag, steam / water volume distortion, and heat storage / release; performing lag effect correction to obtain the correction deviation; determining the dominant control loop and the target adjustment amount for the actuator based on this; and updating the storage areas for each effect after adjustment. This method is applicable to the automatic adjustment and control of steam boilers under multiple operating conditions.

Description

Technical Field

[0001] This invention relates to the field of intelligent control technology for steam boilers, specifically to an adaptive adjustment method and system for steam boilers under various operating conditions. Background Technology

[0002] Steam boilers are key equipment in industrial heating, power drive, and energy conversion, widely used in power, chemical, metallurgical, building materials, food processing, and district heating sectors. With the increasing continuity of industrial production, more frequent load changes, and ever-increasing demands for energy conservation and emission reduction, steam boiler control methods have evolved from manual operation and single-loop instrumentation to conventional PID automatic control, and now towards multi-variable linkage control and intelligent control. Existing boiler control systems can automatically control steam pressure, drum water level, main steam temperature, and the combustion process; however, their ability to adapt to dynamic characteristics during transitions between different operating conditions under complex conditions still needs improvement.

[0003] Most existing steam boiler regulation methods are based on direct control decisions using currently acquired parameters. They typically use instantaneous deviations in steam pressure, water level, and temperature as the main basis for regulation, without fully considering the hysteresis effect between combustion heat release and steam-side response, the volumetric distortion of the steam drum water level under load fluctuations, and the continuation effect of heat storage and release from the heating surface on subsequent operating conditions. This leads to problems such as inaccurate operating condition identification, unreasonable switching of regulation loops, and repeated or excessive regulation of actuators under various operating conditions such as load increase, load decrease, sudden load changes, and fuel fluctuations. Consequently, steam pressure fluctuations, water level instability, and decreased temperature control accuracy are caused. Therefore, an adaptive regulation method for steam boilers that is suitable for multiple operating conditions is needed to solve the above problems. Summary of the Invention

[0004] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an adaptive adjustment method and system for steam boilers under various operating conditions, thus solving the aforementioned problems.

[0005] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: an adaptive adjustment method for steam boilers under various operating conditions, comprising: S1. Collect the operating parameters of the steam boiler and the action parameters of the actuator, and determine the current operating condition based on the operating parameters; S2. Based on the current operating condition and the recent actuator action parameters, construct the heating lag effect storage area, the steam-water volume change effect storage area, and the heat storage and release effect storage area corresponding to the current operating condition. When the operating condition switching boundary is detected, retain the remaining effect in the effect storage area corresponding to the previous operating condition and transfer it to the effect storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition. S3. Based on the storage area of ​​the heating lag effect, the storage area of ​​the steam-water volume change effect, and the storage area of ​​the heat storage and release effect, perform lag effect correction on the current operating parameters to obtain the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation. S4. Based on the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation, determine the current dominant control loop, and determine the target adjustment amount of the actuator corresponding to the current dominant control loop; S5. Control the corresponding actuator of the steam boiler to adjust according to the target adjustment amount of the actuator, and update the heat supply lag effect storage area, the steam-water volume change effect storage area and the heat storage and release effect storage area according to the adjusted operating parameters.

[0006] Furthermore, the operating parameters include steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content; The actuator operation parameters include fuel regulation actuator operation parameters, air supply regulation actuator operation parameters, induced draft regulation actuator operation parameters, water supply regulation actuator operation parameters, and desuperheating regulation actuator operation parameters.

[0007] Furthermore, determining the current operating condition based on the operating parameters includes: In the first sampling period, the preset initial operating condition is determined as the current operating condition; In non-first sampling cycles, the current operating condition is determined according to preset operating condition criteria based on steam pressure deviation, steam drum water level deviation, steam flow rate change rate, feedwater flow rate change rate, main steam temperature deviation, and flue gas oxygen content change. When the absolute value of the steam pressure deviation is greater than the first threshold, the absolute value of the steam drum water level deviation is greater than the second threshold, and the absolute value of the steam flow rate change rate is greater than the third threshold, it is determined to be a load change condition. When the steam pressure deviation is negative and its absolute value is greater than the fourth threshold, the steam flow rate change rate is greater than the fifth threshold, and the feedwater flow rate change rate is greater than the sixth threshold, it is determined to be a load increase condition. When the steam pressure deviation is positive and its absolute value is greater than the seventh threshold, the steam flow rate change rate is negative and its absolute value is greater than the eighth threshold, and the feedwater flow rate change rate is negative and its absolute value is greater than the ninth threshold, it is determined to be a load reduction condition. When the absolute value of the main steam temperature deviation is greater than the tenth threshold and the absolute value of the change in flue gas oxygen content is greater than the eleventh threshold, it is determined to be a fuel fluctuation condition. When the steam pressure deviation is within the first preset range, the steam drum water level deviation is within the second preset range, the absolute value of the steam flow rate change rate is less than the twelfth threshold, the absolute value of the feedwater flow rate change rate is less than the thirteenth threshold, the main steam temperature deviation is within the third preset range, and the absolute value of the flue gas oxygen content change is less than the fourteenth threshold, it is determined to be a low-load steady-state operating condition. The preset operating condition criteria are matched sequentially according to the following conditions: sudden load change, increased load, decreased load, fuel fluctuation, and low load steady state, in order to determine the current operating condition. If none of the preset operating condition criteria are met, the current operating condition determined in the previous sampling period is maintained.

[0008] Furthermore, the construction of the storage area for the heating lag effect, the storage area for the vapor-water volume change effect, and the storage area for the heat storage and release effect corresponding to the current operating condition includes: Based on the operating parameters of the fuel regulating actuator, the air supply regulating actuator, and the induced draft regulating actuator, the heating lag effect is determined and written into the heating lag effect storage area. Based on the steam drum water level, steam flow rate, and the action parameters of the feedwater regulating actuator, the influence of steam and water volume distortion is determined and written into the steam and water volume distortion influence storage area. Based on the main steam temperature, the operating parameters of the fuel regulation actuator, and the operating parameters of the air supply regulation actuator, the amount of heat storage and release influence is determined and written into the heat storage and release influence storage area.

[0009] Furthermore, the step of retaining the remaining influence quantity in the influence quantity storage area corresponding to the previous operating condition when detecting the operating condition switching boundary, and transferring it to the influence quantity storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition, includes: When the current operating condition determined by two consecutive sampling cycles changes, and the absolute value of the steam flow rate change rate is greater than the fifteenth threshold, it is determined that the operating condition switching boundary has been detected. The remaining impact quantities in the impact quantity storage area corresponding to the previous operating condition are retained; Based on the attenuation coefficient corresponding to the current operating condition, the remaining influence quantity after retention is transferred to the influence quantity storage area corresponding to the current operating condition.

[0010] Furthermore, S3 includes: The steam pressure deviation is corrected based on the heating lag effect in the heating lag effect storage area to obtain the corrected steam pressure deviation; The steam drum water level deviation is corrected based on the steam and water volume distortion influence amount in the steam and water volume distortion influence amount storage area to obtain the corrected steam drum water level deviation. The main steam temperature deviation is corrected based on the heat storage and heat release influence in the heat storage area to obtain the corrected main steam temperature deviation.

[0011] Furthermore, S4 includes: Compare the absolute values ​​of the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation; When the absolute value of the corrected steam pressure deviation is at its maximum, the combustion regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the fuel regulation actuator is determined. When the absolute value of the correction of the steam drum water level deviation is the largest, the feedwater regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the feedwater regulation actuator is determined. When the absolute value of the corrected main steam temperature deviation is the largest, the desuperheating regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the desuperheating regulation actuator is determined. When there are equal maximum values, the current dominant control loop is determined in the order of combustion control loop, water supply control loop, and desuperheating control loop, and the target control amount of the corresponding actuator is determined.

[0012] Furthermore, S5 includes: Obtain the actual action of the actuator, as well as the adjusted steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content; Based on the actual action of the actuator and the adjusted steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature and flue gas oxygen content, update the remaining influence quantities in the heating lag influence quantity storage area, the steam and water volume virtual change influence quantity storage area and the heat storage and release influence quantity storage area. Determine the updated current operating conditions based on the updated operating parameters; The corresponding attenuation coefficient is re-determined based on the updated current operating conditions.

[0013] This invention also provides an adaptive control system for steam boilers under various operating conditions, including: The parameter acquisition module is used to acquire the operating parameters of the steam boiler and the action parameters of the actuators, and to determine the current operating condition based on the operating parameters. The impact quantity management module is used to construct a storage area for the impact quantity of heating lag, the impact quantity of steam and water volume change, and the impact quantity of heat storage and release corresponding to the current operating condition based on the current operating condition and the recent actuator action parameters. When the operating condition switching boundary is detected, the remaining impact quantity in the impact quantity storage area corresponding to the previous operating condition is retained and transferred to the impact quantity storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition. The correction module is used to perform lag effect correction on the current operating parameters based on the heating lag effect storage area, the steam-water volume change effect storage area, and the heat storage and release effect storage area, to obtain the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation. The adjustment decision module is used to determine the current dominant adjustment loop based on the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation, and to determine the target adjustment amount of the actuator corresponding to the current dominant adjustment loop; The execution update module is used to control the corresponding actuator of the steam boiler to adjust according to the target adjustment amount of the actuator, and update the heat supply lag effect storage area, the steam-water volume change effect storage area and the heat storage and release effect storage area according to the adjusted operating parameters.

[0014] (III) Beneficial Effects Compared with the prior art, the present invention provides an adaptive adjustment method and system for steam boilers under various operating conditions, which has the following beneficial effects: 1. This adaptive regulation method and system for steam boilers under multiple operating conditions constructs storage areas for heating lag effects, steam-water volume variation effects, and heat storage and release effects based on the current operating conditions and recent actuator action parameters. At the operating condition switching boundary, it retains and transfers the remaining effects from the previous operating condition. Then, based on each of these storage areas, it corrects the lag effects on the current operating parameters to obtain corrected steam pressure deviations, corrected drum water level deviations, and corrected main steam temperature deviations. Finally, based on the corrected deviations, it determines the current dominant regulation loop and the target regulation amount for the actuator. This method can separate the lag in combustion heat transfer, the variation in drum water level and volume, and the heat storage and release effects from the current instantaneous deviations, avoiding the direct use of apparent deviations as control criteria. This improves the accuracy of operating condition judgment and the targeted nature of regulation decisions under multiple operating conditions, reduces problems such as unreasonable regulation loop switching, redundant actuator regulation, and over-regulation, and enhances the control stability and regulation accuracy of steam pressure, water level, and temperature. Attached Figure Description

[0015] Figure 1 This is a schematic diagram illustrating the steps of the adaptive adjustment method for steam boilers under various operating conditions provided by the present invention.

[0016] Figure 2 This is a flowchart illustrating the adaptive adjustment method for steam boilers under various operating conditions provided by the present invention.

[0017] Figure 3 This is a flowchart illustrating the process of determining the current operating condition based on operating parameters, provided by the present invention.

[0018] Figure 4 This is a schematic diagram of the structure of the adaptive adjustment system for a steam boiler under various operating conditions provided by the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0020] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] In this embodiment, "recent" is preferably the data range corresponding to the three consecutive sampling periods before the current sampling period. If necessary, it can also be extended to the data range of the five consecutive sampling periods before the current sampling period, depending on the boiler capacity, sampling period and load change rate. The “Storage Area” is a data table divided by operating condition category and impact type. Each table item includes at least the operating condition identifier, impact quantity type, new impact quantity in the current period, retained impact quantity in the previous period, cumulative impact quantity in the current period, update time, and associated execution agency identifier. "Residual impact" refers to the effective cumulative impact of an actuator that was generated in a previous sampling period, has not been completely eliminated after attenuation calculation, and continues to participate in the status correction of the current sampling period. The "attenuation coefficient" is a set of parameters used to characterize the proportion of the remaining influence between adjacent sampling periods, with a value of 0 to 1. The attenuation coefficient is set according to the operating conditions and includes coefficient components corresponding to the effects of heating lag, steam-water volume change and heat storage and release, respectively. Each coefficient component can be corrected according to the actual adjustment effect. "Target adjustment" is an incremental adjustment relative to the current output value of the actuator, used to convert the decision result of the dominant control loop into the control quantity that the corresponding actuator should increase or decrease within the current sampling period.

[0022] Please see Figure 1-2 , Figure 1A schematic diagram illustrating the steps of the adaptive adjustment method for steam boilers under various operating conditions provided by the present invention; Figure 2 This is a flowchart illustrating the adaptive regulation method for a steam boiler under multiple operating conditions provided by the present invention. The present invention provides an adaptive regulation method for a steam boiler under multiple operating conditions, comprising: S1. Collect the operating parameters of the steam boiler and the action parameters of the actuator, and determine the current operating condition based on the operating parameters; Specifically, the controller synchronously reads measurement data from the boiler body, steam-water system, and combustion system at the sampling time, and also reads the action data of each actuator within the current cycle. The collected results are written into the current cycle data record with a unified timestamp. The operating parameters are used to characterize the thermal state of the boiler at the current moment, and the actuator action parameters are used to characterize the control actions that each regulating loop has implemented within the current cycle.

[0023] Furthermore, in one embodiment provided by the present invention, the operating parameters include steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content. The actuator operation parameters include fuel regulation actuator operation parameters, air supply regulation actuator operation parameters, induced draft regulation actuator operation parameters, water supply regulation actuator operation parameters, and desuperheating regulation actuator operation parameters.

[0024] Specifically, steam pressure characterizes the instantaneous relationship between steam-side output capacity and load demand; drum water level characterizes the liquid level status of the steam-water system; steam flow rate and feedwater flow rate characterize load changes and water replenishment changes; main steam temperature characterizes the heat exchange status on the steam side; and flue gas oxygen content characterizes the combustion air distribution status. The operating parameters of the fuel regulating actuator, forced draft regulating actuator, and induced draft regulating actuator reflect combustion-side regulation behavior; the feedwater regulating actuator reflects steam-water side water replenishment behavior; and the desuperheating regulating actuator reflects steam temperature regulation behavior.

[0025] In one embodiment, steam pressure, drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content are collected by a pressure transmitter, a level transmitter, a flow meter, a temperature sensor, and an oxygen analyzer, respectively; the action parameters of each actuator are obtained from valve position feedback values, damper opening feedback values, feed command feedback values, or controller output records. The controller aligns the above parameters according to the same sampling period to form the current period's status data group and action data group, which can then be directly used for subsequent operating condition identification.

[0026] For further details, please refer to Figure 3 , Figure 3This invention provides a flowchart illustrating the process of determining the current operating condition based on operating parameters. In one embodiment of this invention, determining the current operating condition based on the operating parameters includes: In the first sampling period, the preset initial operating condition is determined as the current operating condition; In non-first sampling cycles, the current operating condition is determined according to preset operating condition criteria based on steam pressure deviation, steam drum water level deviation, steam flow rate change rate, feedwater flow rate change rate, main steam temperature deviation, and flue gas oxygen content change. When the absolute value of the steam pressure deviation is greater than the first threshold, the absolute value of the steam drum water level deviation is greater than the second threshold, and the absolute value of the steam flow rate change rate is greater than the third threshold, it is determined to be a load change condition. When the steam pressure deviation is negative and its absolute value is greater than the fourth threshold, the steam flow rate change rate is greater than the fifth threshold, and the feedwater flow rate change rate is greater than the sixth threshold, it is determined to be a load increase condition. When the steam pressure deviation is positive and its absolute value is greater than the seventh threshold, the steam flow rate change rate is negative and its absolute value is greater than the eighth threshold, and the feedwater flow rate change rate is negative and its absolute value is greater than the ninth threshold, it is determined to be a load reduction condition. When the absolute value of the main steam temperature deviation is greater than the tenth threshold and the absolute value of the change in flue gas oxygen content is greater than the eleventh threshold, it is determined to be a fuel fluctuation condition. When the steam pressure deviation is within the first preset range, the steam drum water level deviation is within the second preset range, the absolute value of the steam flow rate change rate is less than the twelfth threshold, the absolute value of the feedwater flow rate change rate is less than the thirteenth threshold, the main steam temperature deviation is within the third preset range, and the absolute value of the flue gas oxygen content change is less than the fourteenth threshold, it is determined to be a low-load steady-state operating condition. The preset operating condition criteria are matched sequentially according to the following conditions: sudden load change, increased load, decreased load, fuel fluctuation, and low load steady state, in order to determine the current operating condition. If none of the preset operating condition criteria are met, the current operating condition determined in the previous sampling period is maintained.

[0027] Specifically, the first sampling period is used to initialize the operating condition determination link. During this period, the controller does not perform multi-condition criterion matching, but instead directly writes the preset initial operating condition into the current operating condition register unit to provide the basis for operating condition inheritance for the next sampling period. The preset initial operating condition can be set to a low-load steady-state operating condition, the default operating condition after startup, or the preset operating condition during the commissioning phase, depending on the boiler commissioning method.

[0028] In non-first sampling periods, the controller first calculates each judgment quantity based on the current sampled value and the sampled value of the previous sampling period. Specifically, the steam pressure deviation equals the difference between the current steam pressure and the target steam pressure value; the drum water level deviation equals the difference between the current drum water level and the target drum water level value; and the main steam temperature deviation equals the difference between the current main steam temperature and the target main steam temperature value. The steam flow rate change rate, feedwater flow rate change rate, and flue gas oxygen content change rate are obtained by dividing the difference between the current sampled value and the sampled value of the previous sampling period by the sampling period. To reduce the impact of measurement noise on operating condition judgment, a low-pass filter or moving average processing can be performed on the steam pressure, drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content before calculating the above judgment quantities. The first threshold to the fifteenth threshold and the first preset range to the third preset range can be adjusted based on boiler rated operating condition test data, historical operating data statistics, and step disturbance identification results, and stored in the operating condition parameter table according to boiler model, rated evaporation capacity, and fuel type.

[0029] After obtaining the various judgment values, the controller performs condition matching sequentially according to the following conditions: load change, load increase, load decrease, fuel fluctuation, and low load steady-state. When a condition criterion is successfully matched for the first time, the corresponding condition is immediately written into the current condition register and the condition judgment for this cycle ends. When all criteria fail to match, the current condition from the previous sampling cycle remains unchanged. To avoid frequent switching of conditions in the critical range, the new condition criterion can be required to be met for two consecutive sampling cycles before condition writing is performed; or, condition writing can be performed when the difference between the judgment values ​​of the current condition and the candidate condition is greater than a preset switching margin. If necessary, at least one of the above two conditions can be met simultaneously to balance the sensitivity and stability of condition switching. After this processing, each sampling cycle corresponds to a unique current condition output, and the condition jitter caused by slight parameter fluctuations can be reduced.

[0030] S2. Based on the current operating condition and the recent actuator action parameters, construct the heating lag effect storage area, the steam-water volume change effect storage area, and the heat storage and release effect storage area corresponding to the current operating condition. When the operating condition switching boundary is detected, retain the remaining effect in the effect storage area corresponding to the previous operating condition and transfer it to the effect storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition. Specifically, the controller uses the current operating condition as the index and the recent actuator action parameters as the input for calculating the impact. Within the current sampling period, it establishes three impact storage areas: a heating lag impact area, a steam-water volume change impact area, and a heat storage and release impact area. These three impact storage areas are used to classify and record historical effects that have not yet completely dissipated under the current operating condition. Specifically, the heating lag impact area corresponds to the continued effect of combustion-side actions that are transmitted to the steam side in subsequent sampling periods; the steam-water volume change impact area corresponds to the apparent changes in the steam drum water level caused by load changes and feedwater changes; and the heat storage and release impact area corresponds to the continued heat release or absorption caused by the heat capacity of the heating surface and the steam system.

[0031] Within the same sampling period, the controller writes the newly formed influence quantities of the current period into the data table entry corresponding to the current operating condition, and reads the remaining influence quantities retained from the previous sampling period to participate in the cumulative recording of the current period. When a switch between the current operating condition and the operating condition of the previous sampling period is detected, the controller does not directly clear the undiminished portions in the storage area of ​​each influence quantity under the previous operating condition. Instead, it first performs retention processing, and then transfers the undiminished portions to the data table entry corresponding to the current operating condition according to the attenuation coefficient. This allows the influence quantities that were formed before the operating condition switch but have not yet completely diminished to continue to participate in subsequent operating parameter corrections.

[0032] Furthermore, in one embodiment of the present invention, the construction of the storage area for the heating lag effect, the storage area for the vapor-water volume change effect, and the storage area for the heat storage and release effect corresponding to the current operating condition includes: Based on the operating parameters of the fuel regulating actuator, the air supply regulating actuator, and the induced draft regulating actuator, the heating lag effect is determined and written into the heating lag effect storage area. Based on the steam drum water level, steam flow rate, and the action parameters of the feedwater regulating actuator, the influence of steam and water volume distortion is determined and written into the steam and water volume distortion influence storage area. Based on the main steam temperature, the operating parameters of the fuel regulation actuator, and the operating parameters of the air supply regulation actuator, the amount of heat storage and release influence is determined and written into the heat storage and release influence storage area.

[0033] Specifically, the controller performs incremental and cumulative calculations for the three types of influencing quantities. For the heating lag impact, the controller obtains the actual increments of the fuel regulating actuator, the supply air regulating actuator, and the induced draft air regulating actuator within the current sampling period based on their operating parameters, and determines the newly added heating lag impact accordingly. Within each sampling period, the additional impact of heating lag can be expressed as: Additional impact of heating lag = ×Actual action increment of fuel regulation actuator + ×Actual action increment of air supply regulation actuator + ×Increment in actual movement of the induced draft regulating actuator.

[0034] Regarding the impact of steam-water volume distortion, the controller, based on the steam drum water level, steam flow rate, and feedwater regulating actuator action parameters, first determines the steam drum water level deviation from the target value, then determines the steam flow rate change rate from the current steam flow rate and the steam flow rate of the previous sampling period, and finally determines the actual action increment of the feedwater regulating actuator based on the actuator action parameters. Finally, it determines the additional impact of steam-water volume distortion based on the steam drum water level deviation, the steam flow rate change rate, and the actual action increment of the feedwater regulating actuator. Within each sampling period, the incremental impact of the artificial change in the volume of carbonated beverage can be expressed as: Incremental impact of artificial change in the volume of carbonated beverage = ×Steam flow rate change rate- ×Actual action increment of water supply regulation actuator + × Steam drum water level deviation.

[0035] Regarding the impact of heat storage and release, the controller, based on the main steam temperature, the operating parameters of the fuel regulating actuator, and the operating parameters of the air supply regulating actuator, first determines the deviation of the main steam temperature from the target value. Then, it determines the actual increment of the fuel regulating actuator and the actual increment of the air supply regulating actuator based on the operating parameters of the fuel regulating actuator and the air supply regulating actuator, respectively, and determines the additional impact of heat storage and release accordingly. Within each sampling period, the additional impact of heat storage and heat release can be expressed as: Additional impact of heat storage and heat release = ×Main steam temperature deviation+ ×Actual action increment of fuel regulation actuator + ×Increment in actual movement of the air supply regulation actuator.

[0036] in, arrive , arrive , arrive The conversion factors set separately for each working condition can be adjusted and stored in the working condition parameter table based on the rated working condition test data, historical operating data statistics, or step identification results.

[0037] All three types of impact quantities are stored in data tables categorized by operating condition. Each table entry includes at least the operating condition identifier, the newly added impact quantity in the current period, the retained impact quantity from the previous period, the cumulative impact quantity in the current period, the update time, and the identifier of the associated executing agency. The cumulative impact quantity in the current period equals the sum of the retained impact quantity from the previous period and the newly added impact quantity in the current period. If necessary, the cumulative impact quantity in the current period can also be limited to avoid distortion of the cumulative impact quantity caused by abnormal sampling values.

[0038] Furthermore, in one embodiment of the present invention, when a working condition switching boundary is detected, the remaining influence quantity in the influence quantity storage area corresponding to the previous working condition is retained, and transferred to the influence quantity storage area corresponding to the current working condition according to the attenuation coefficient corresponding to the current working condition, includes: When the current operating condition determined by two consecutive sampling cycles changes, and the absolute value of the steam flow rate change rate is greater than the fifteenth threshold, it is determined that the operating condition switching boundary has been detected. The remaining impact quantities in the impact quantity storage area corresponding to the previous operating condition are retained; Based on the attenuation coefficient corresponding to the current operating condition, the remaining influence quantity after retention is transferred to the influence quantity storage area corresponding to the current operating condition.

[0039] Specifically, the operating condition switching boundary is used to identify when the boiler has transitioned from one operating condition to another, and when this change has reached a point where continued impact processing is required. In one embodiment, the controller first compares whether the current operating conditions determined by two consecutive sampling periods are consistent; if they are inconsistent, it calculates the absolute value of the steam flow rate change rate in the current sampling period and compares it with the fifteenth threshold. When the operating condition changes and the absolute value of the steam flow rate change rate is greater than the fifteenth threshold, the operating condition switching boundary is considered to have occurred. For fuel fluctuation conditions, to avoid missed detection due to insignificant steam flow rate changes, the absolute value of the main steam temperature deviation being greater than the tenth threshold and the absolute value of the change in flue gas oxygen content being greater than the eleventh threshold can also be used as auxiliary confirmation conditions. To prevent frequent switching of critical intervals, the operating condition switching boundary preferably takes effect after one hysteresis judgment.

[0040] After identifying the operating condition switching boundary, the controller reads the remaining cumulative impact from the storage areas for heating lag impact, steam-water volume variation impact, and heat storage / release impact corresponding to the previous operating condition, as the remaining impact. Then, it uses the attenuation coefficient corresponding to the current operating condition to calculate the remaining impact, obtaining the transferred impact, and writes the transferred impact into the three impact storage areas corresponding to the current operating condition. The attenuation coefficient corresponding to the current operating condition is a set of coefficient components set according to the impact type, including the heating lag impact attenuation coefficient, the steam-water volume variation impact attenuation coefficient, and the heat storage / release impact attenuation coefficient, with each coefficient component taking a value between 0 and 1.

[0041] Through the above processing, in the first or several consecutive sampling cycles after the change of operating conditions, the lingering effects of the previous operating condition that have been formed but have not yet completely dissipated can still participate in the subsequent correction calculations under the current operating condition, thereby avoiding the direct discarding of this part of the influence when the operating conditions are changed, which would cause the current cycle input to be inconsistent with the actual thermal process.

[0042] S3. Based on the storage area of ​​the heating lag effect, the storage area of ​​the steam-water volume change effect, and the storage area of ​​the heat storage and release effect, perform lag effect correction on the current operating parameters to obtain the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation. Specifically, the controller first reads the steam pressure deviation, steam drum water level deviation, and main steam temperature deviation for the current sampling period. Then, it reads the cumulative impact quantities corresponding to the current operating condition from the heat supply lag impact quantity storage area, the steam-water volume change impact quantity storage area, and the heat storage and release impact quantity storage area. Subsequently, the controller applies the three types of cumulative impact quantities to the corresponding deviation quantities, separating the impact caused by the continuation of historical actions in the current sampling period from the original deviation, thus forming the corrected deviation result.

[0043] In one embodiment, the steam pressure deviation is mainly affected by the lag in the combustion-side action, the drum water level deviation is mainly affected by the virtual change in steam and water volume, and the main steam temperature deviation is mainly affected by the heat transfer surface and the heat storage and release of the steam system. The controller completes the three corrections within the same sampling period and writes the corrected steam pressure deviation, corrected drum water level deviation, and corrected main steam temperature deviation into the current period's control variable area for the next step to select the dominant control loop. After this processing, the deviation entering the next step is no longer directly equal to the original measurement deviation, but corresponds to the deviation result after deducting the historical continuation effect.

[0044] Furthermore, in one embodiment provided by the present invention, S3 includes: The steam pressure deviation is corrected based on the heating lag effect in the heating lag effect storage area to obtain the corrected steam pressure deviation; The steam drum water level deviation is corrected based on the steam and water volume distortion influence amount in the steam and water volume distortion influence amount storage area to obtain the corrected steam drum water level deviation. The main steam temperature deviation is corrected based on the heat storage and heat release influence in the heat storage area to obtain the corrected main steam temperature deviation.

[0045] Specifically, in the Within each sampling period, the controller reads the cumulative impact value corresponding to the current operating condition from the corresponding impact value storage area and obtains each correction value according to the conversion coefficient in the operating condition parameter table. Specifically, the pressure correction value equals the pressure conversion coefficient multiplied by the cumulative impact value of heating lag; the water level correction value equals the water level conversion coefficient multiplied by the cumulative impact value of steam-water volume variation; and the temperature correction value equals the temperature conversion coefficient multiplied by the cumulative impact value of heat storage and release. The corrected steam pressure deviation equals the current steam pressure deviation minus the pressure correction value; the corrected steam drum water level deviation equals the current steam drum water level deviation minus the water level correction value; and the corrected main steam temperature deviation equals the current main steam temperature deviation minus the temperature correction value.

[0046] When the cumulative impact of heating lag, the cumulative impact of steam-water volume distortion, or the cumulative impact of heat storage and release, representing historical actions, continues to have an effect, the corresponding correction value is used to offset the continued impact portion of the current original deviation. When the corresponding cumulative impact, representing historical reverse actions, continues to have an effect, the corresponding correction value participates in the correction in the opposite direction. To avoid overcorrection caused by excessively large correction values, pressure correction values, water level correction values, and temperature correction values ​​are preferably subjected to amplitude limiting. The amplitude limiting value can be set according to the allowable deviation range of each control quantity under rated operating conditions.

[0047] In one embodiment, the pressure conversion factor, water level conversion factor, and temperature conversion factor are set separately according to the operating conditions. They can be adjusted based on rated operating condition test data, historical operating data statistics, or online identification results, and stored in the operating condition parameter table. After completing the three corrections, the controller synchronously outputs the corrected steam pressure deviation, corrected steam drum water level deviation, and corrected main steam temperature deviation to the dominant control loop determination module for subsequent comparison of the absolute values ​​of the three deviations and determination of the dominant control direction for the current sampling period.

[0048] S4. Based on the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation, determine the current dominant control loop, and determine the target adjustment amount of the actuator corresponding to the current dominant control loop; Specifically, the controller uses the corrected steam pressure deviation, corrected drum water level deviation, and corrected main steam temperature deviation obtained in the current sampling cycle as the basis for loop selection in this cycle. First, the absolute values ​​of the three correction deviations are calculated, and then the magnitudes of the three absolute values ​​are compared to determine the dominant control loop that will operate first in this cycle. To avoid frequent switching of the dominant loop due to minor deviations, it is preferable to first determine whether the absolute values ​​of the three correction deviations are all greater than their respective corresponding dead zone thresholds; only when the absolute value of a certain correction deviation is greater than its corresponding dead zone threshold and is the maximum value is its corresponding loop determined as the current dominant control loop.

[0049] After determining the current dominant control loop, the controller only calculates the target adjustment amount for the actuator corresponding to that loop. Other loops maintain their original output or operate according to existing follow-up logic, but are still subject to safety interlocks and operational constraints. To prevent the dominant loop from frequently switching back and forth between adjacent sampling periods, when the difference between the absolute values ​​of two correction deviations is less than a preset parallel threshold, the dominant control loop of the previous sampling period can continue to be maintained, or priority can be determined according to the order of combustion control loop, water supply control loop, and desuperheating control loop.

[0050] Furthermore, in one embodiment provided by the present invention, S4 includes: Compare the absolute values ​​of the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation; When the absolute value of the corrected steam pressure deviation is at its maximum, the combustion regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the fuel regulation actuator is determined. When the absolute value of the correction of the steam drum water level deviation is the largest, the feedwater regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the feedwater regulation actuator is determined. When the absolute value of the corrected main steam temperature deviation is the largest, the desuperheating regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the desuperheating regulation actuator is determined. When there are equal maximum values, the current dominant control loop is determined in the order of combustion control loop, water supply control loop, and desuperheating control loop, and the target control amount of the corresponding actuator is determined.

[0051] Specifically, when comparing the absolute values ​​of the three correction deviations, the controller first reads the correction steam pressure deviation, correction drum water level deviation, and correction main steam temperature deviation within the current sampling period. Then, it calculates the absolute values ​​of each deviation and writes them into the current cycle's loop determination unit. If the absolute value of the correction steam pressure deviation is the largest, it indicates that the steam-side deviation dominates within the current sampling period. The controller then determines the combustion regulation loop as the current dominant regulation loop and generates the target regulation amount for the fuel regulation actuator based on the direction and magnitude of the correction steam pressure deviation. Specifically, when the correction steam pressure deviation is negative, the target regulation amount corresponds to the fuel increase direction; when the correction steam pressure deviation is positive, the target regulation amount corresponds to the fuel decrease direction.

[0052] If the absolute value of the corrected steam drum water level deviation is the largest, it indicates that the steam drum water level deviation is dominant in the current sampling period. The controller will then determine the feedwater regulation loop as the current dominant regulation loop and generate the target regulation amount for the feedwater regulation actuator based on the direction and magnitude of the corrected steam drum water level deviation. Specifically, when the corrected steam drum water level deviation is negative, the target regulation amount corresponds to the direction of increasing feedwater; when the corrected steam drum water level deviation is positive, the target regulation amount corresponds to the direction of decreasing feedwater.

[0053] If the absolute value of the corrected main steam temperature deviation is the largest, it indicates that the steam temperature deviation is dominant in the current sampling period. The controller will then determine the desuperheating control loop as the current dominant control loop and generate the target adjustment amount for the desuperheating control actuator based on the direction and magnitude of the corrected main steam temperature deviation. Specifically, when the corrected main steam temperature deviation is positive, the target adjustment amount corresponds to the direction of increasing desuperheating; when the corrected main steam temperature deviation is negative, the target adjustment amount corresponds to the direction of decreasing desuperheating.

[0054] When two or three correction deviations have equal absolute values, or when the difference between the maximum and second-largest values ​​is less than a preset parallel threshold, the controller first determines whether the dominant control loop of the previous sampling period still meets the corresponding dead zone threshold. If it does, the dominant control loop of the previous sampling period is maintained to reduce the probability of loop switching. If it does not meet the threshold, priority is determined according to the order of combustion control loop, water supply control loop, and desuperheating control loop. After processing in this order, each sampling period outputs only one current dominant control loop and one corresponding actuator target adjustment amount.

[0055] In one embodiment, the target adjustment amount of the actuator is given in the form of an incremental adjustment amount. For the first... The target adjustment amount of a single dominant control loop can be expressed as: Target adjustment amount = Direction coefficient × Control gain × Corresponding correction deviation. Here, the direction coefficient characterizes the direction of increase or decrease of the actuator, and the control gain is set according to the operating conditions and stored in the operating condition parameter table. To avoid excessive actuator movement, the target adjustment amount is preferably sent to the corresponding actuator control unit after amplitude limiting and rate of change limiting; the amplitude limiting can be set according to the allowable range of actuator movement, and the rate of change limiting can be set according to the maximum allowable step size within a single sampling period.

[0056] S5. Control the corresponding actuator of the steam boiler to adjust according to the target adjustment amount of the actuator, and update the heat supply lag effect storage area, the steam-water volume change effect storage area and the heat storage and release effect storage area according to the adjusted operating parameters.

[0057] Specifically, the controller sends the target adjustment amount output by the actuators in the current sampling cycle to the corresponding actuators, enabling the fuel regulation actuator, feedwater regulation actuator, or desuperheating regulation actuator to complete the cycle's action in the target direction. After the action is completed, the controller does not immediately end the cycle processing but continues to read the feedback data after execution. It uses the adjusted operating parameters and the actual action amount of the actuators to write back the three types of influence quantity storage areas, so that the regulation actions that have occurred in the current cycle can continue to participate in the hysteresis correction in the next sampling cycle.

[0058] In one embodiment, if the current dominant control loop is a combustion control loop, the controller outputs the target increment for the current cycle to the fuel control actuator, and after execution, collects the corresponding feedback opening degree, the corresponding fuel quantity change, and the adjusted steam pressure, steam flow rate, and main steam temperature. If the current dominant control loop is a feedwater control loop, the controller outputs the target increment for the current cycle to the feedwater control actuator, and after execution, collects the corresponding feedback opening degree, the corresponding feedwater quantity change, and the adjusted steam drum water level and feedwater flow rate. If the current dominant control loop is a desuperheating control loop, the controller outputs the target increment for the current cycle to the desuperheating control actuator, and after execution, collects the corresponding feedback opening degree, the corresponding desuperheating water quantity change, and the adjusted main steam temperature. After acquiring the feedback data for the current cycle, the controller uses it as input data for calculating the impact amount and re-identifying the operating condition in the next sampling cycle.

[0059] Furthermore, in one embodiment provided by the present invention, S5 includes: Obtain the actual action of the actuator, as well as the adjusted steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content; Based on the actual action of the actuator and the adjusted steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature and flue gas oxygen content, update the remaining influence quantities in the heating lag influence quantity storage area, the steam and water volume virtual change influence quantity storage area and the heat storage and release influence quantity storage area. Determine the updated current operating conditions based on the updated operating parameters; The corresponding attenuation coefficient is re-determined based on the updated current operating conditions.

[0060] Specifically, when obtaining the actual action amount of the actuators, the controller reads the actual feedback value of each actuator at the end of the current sampling period and compares the feedback value with the execution value at the beginning of the current sampling period to obtain the actual action increment of the current period; the adjusted steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature and flue gas oxygen content are given by the effective measurement values ​​at the end of the current sampling period, which are used to characterize the actual state of the boiler after the current adjustment action is applied.

[0061] When updating the remaining impact quantities in the three types of impact quantity storage areas, the controller prefers to update based on the actual action quantity of the actuator rather than the target adjustment quantity, so that the impact quantity calculation more accurately reflects the true output of the actuator. The controller first reads the remaining impact quantity of the previous cycle corresponding to the current operating condition, and then combines it with the actual action quantity of the actuator in the current cycle and the adjusted operating parameters to form the newly added impact quantity for the current cycle. This newly added impact quantity is then merged with the remaining impact quantity of the previous cycle to obtain the updated remaining impact quantity. If necessary, the updated remaining impact quantity can be limited.

[0062] When determining the updated current operating condition, the controller uses the operating parameters at the end of the current cycle as the input for the next sampling cycle, and re-executes the operating condition identification according to the predetermined operating condition determination order to obtain the updated current operating condition. When re-determining the corresponding attenuation coefficient, the controller retrieves the attenuation coefficient corresponding to the operating condition from the operating condition parameter table based on the updated current operating condition, and writes it into the coefficient fields corresponding to the heating lag effect, steam-water volume change effect, and heat storage and release effect, respectively. If the updated current operating condition is consistent with the current operating condition at the beginning of the current cycle, the attenuation coefficient corresponding to the same operating condition will continue to be used; if the updated current operating condition changes, the controller will switch to the attenuation coefficient corresponding to the new operating condition, and use it in the remaining effect retention and transfer process in the next sampling cycle.

[0063] When sensor sampling anomalies, feedback signals are missing, or actuator actions fail to reach target values, the controller can retain valid parameters from the previous sampling period or use the most recent valid sample value to complete the update for the current period, and record the abnormal state to prevent abnormal data from directly entering the impact quantity update process. Through the above processing, the execution result of the current sampling period can be directly converted into the impact quantity input, operating condition input, and attenuation coefficient input for the next sampling period, thus forming a continuous periodic processing process of acquisition, judgment, storage, correction, adjustment, and updating.

[0064] Please see Figure 4 , Figure 4 This is a schematic diagram of the adaptive regulation system for a steam boiler under multiple operating conditions provided by the present invention. The present invention also provides an adaptive regulation system for a steam boiler under multiple operating conditions, which is used to implement the methods described in the above embodiments, including: The parameter acquisition module is used to acquire the operating parameters of the steam boiler and the action parameters of the actuators, and to determine the current operating condition based on the operating parameters. The impact quantity management module is used to construct a storage area for the impact quantity of heating lag, the impact quantity of steam and water volume change, and the impact quantity of heat storage and release corresponding to the current operating condition based on the current operating condition and the recent actuator action parameters. When the operating condition switching boundary is detected, the remaining impact quantity in the impact quantity storage area corresponding to the previous operating condition is retained and transferred to the impact quantity storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition. The correction module is used to perform lag effect correction on the current operating parameters based on the heating lag effect storage area, the steam-water volume change effect storage area, and the heat storage and release effect storage area, to obtain the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation. The adjustment decision module is used to determine the current dominant adjustment loop based on the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation, and to determine the target adjustment amount of the actuator corresponding to the current dominant adjustment loop; The execution update module is used to control the corresponding actuator of the steam boiler to adjust according to the target adjustment amount of the actuator, and update the heat supply lag effect storage area, the steam-water volume change effect storage area and the heat storage and release effect storage area according to the adjusted operating parameters.

[0065] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0066] 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. An adaptive adjustment method for steam boilers under various operating conditions, characterized in that, include: S1. Collect the operating parameters of the steam boiler and the action parameters of the actuator, and determine the current operating condition based on the operating parameters; S2. Based on the current operating condition and the recent actuator action parameters, construct the heating lag effect storage area, the steam-water volume change effect storage area, and the heat storage and release effect storage area corresponding to the current operating condition. When the operating condition switching boundary is detected, retain the remaining effect in the effect storage area corresponding to the previous operating condition and transfer it to the effect storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition. S3. Based on the storage area of ​​the heating lag effect, the storage area of ​​the steam-water volume change effect, and the storage area of ​​the heat storage and release effect, perform lag effect correction on the current operating parameters to obtain the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation. S4. Based on the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation, determine the current dominant control loop, and determine the target adjustment amount of the actuator corresponding to the current dominant control loop; S5. Control the corresponding actuator of the steam boiler to adjust according to the target adjustment amount of the actuator, and update the heat supply lag effect storage area, the steam-water volume change effect storage area and the heat storage and release effect storage area according to the adjusted operating parameters.

2. The adaptive adjustment method for steam boilers under multiple operating conditions according to claim 1, characterized in that: The operating parameters include steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content. The actuator operation parameters include fuel regulation actuator operation parameters, air supply regulation actuator operation parameters, induced draft regulation actuator operation parameters, water supply regulation actuator operation parameters, and desuperheating regulation actuator operation parameters.

3. The adaptive adjustment method for steam boilers under multiple operating conditions according to claim 2, characterized in that, Determining the current operating condition based on the operating parameters includes: In the first sampling period, the preset initial operating condition is determined as the current operating condition; In non-first sampling cycles, the current operating condition is determined according to preset operating condition criteria based on steam pressure deviation, steam drum water level deviation, steam flow rate change rate, feedwater flow rate change rate, main steam temperature deviation, and flue gas oxygen content change. When the absolute value of the steam pressure deviation is greater than the first threshold, the absolute value of the steam drum water level deviation is greater than the second threshold, and the absolute value of the steam flow rate change rate is greater than the third threshold, it is determined to be a load change condition. When the steam pressure deviation is negative and its absolute value is greater than the fourth threshold, the steam flow rate change rate is greater than the fifth threshold, and the feedwater flow rate change rate is greater than the sixth threshold, it is determined to be a load increase condition. When the steam pressure deviation is positive and its absolute value is greater than the seventh threshold, the steam flow rate change rate is negative and its absolute value is greater than the eighth threshold, and the feedwater flow rate change rate is negative and its absolute value is greater than the ninth threshold, it is determined to be a load reduction condition. When the absolute value of the main steam temperature deviation is greater than the tenth threshold and the absolute value of the change in flue gas oxygen content is greater than the eleventh threshold, it is determined to be a fuel fluctuation condition. When the steam pressure deviation is within the first preset range, the steam drum water level deviation is within the second preset range, the absolute value of the steam flow rate change rate is less than the twelfth threshold, the absolute value of the feedwater flow rate change rate is less than the thirteenth threshold, the main steam temperature deviation is within the third preset range, and the absolute value of the flue gas oxygen content change is less than the fourteenth threshold, it is determined to be a low-load steady-state operating condition. The preset operating condition criteria are matched sequentially according to the following conditions: sudden load change, increased load, decreased load, fuel fluctuation, and low load steady state, in order to determine the current operating condition. If none of the preset operating condition criteria are met, the current operating condition determined in the previous sampling period is maintained.

4. The adaptive adjustment method for steam boilers under multiple operating conditions according to claim 2, characterized in that, The construction of the storage area for the heating lag effect, the storage area for the vapor-water volume change effect, and the storage area for the heat storage and release effect corresponding to the current operating condition includes: Based on the operating parameters of the fuel regulating actuator, the air supply regulating actuator, and the induced draft regulating actuator, the heating lag effect is determined and written into the heating lag effect storage area. Based on the steam drum water level, steam flow rate, and the action parameters of the feedwater regulating actuator, the influence of steam and water volume distortion is determined and written into the steam and water volume distortion influence storage area. Based on the main steam temperature, the operating parameters of the fuel regulation actuator, and the operating parameters of the air supply regulation actuator, the amount of heat storage and release influence is determined and written into the heat storage and release influence storage area.

5. The adaptive adjustment method for steam boilers under multiple operating conditions according to claim 4, characterized in that, The step of retaining the remaining influence quantity in the influence quantity storage area corresponding to the previous operating condition when a working condition switching boundary is detected, and transferring it to the influence quantity storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition, includes: When the current operating condition determined by two consecutive sampling cycles changes, and the absolute value of the steam flow rate change rate is greater than the fifteenth threshold, it is determined that the operating condition switching boundary has been detected. The remaining impact quantities in the impact quantity storage area corresponding to the previous operating condition are retained; Based on the attenuation coefficient corresponding to the current operating condition, the remaining influence quantity after retention is transferred to the influence quantity storage area corresponding to the current operating condition.

6. The adaptive adjustment method for steam boilers under multiple operating conditions according to claim 1, characterized in that, S3 includes: The steam pressure deviation is corrected based on the heating lag effect in the heating lag effect storage area to obtain the corrected steam pressure deviation; The steam drum water level deviation is corrected based on the steam and water volume distortion influence amount in the steam and water volume distortion influence amount storage area to obtain the corrected steam drum water level deviation. The main steam temperature deviation is corrected based on the heat storage and heat release influence in the heat storage area to obtain the corrected main steam temperature deviation.

7. The adaptive adjustment method for steam boilers under multiple operating conditions according to claim 1, characterized in that, S4 includes: Compare the absolute values ​​of the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation; When the absolute value of the corrected steam pressure deviation is at its maximum, the combustion regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the fuel regulation actuator is determined. When the absolute value of the correction of the steam drum water level deviation is the largest, the feedwater regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the feedwater regulation actuator is determined. When the absolute value of the corrected main steam temperature deviation is the largest, the desuperheating regulation loop is determined as the current dominant regulation loop, and the target regulation amount of the desuperheating regulation actuator is determined. When there are equal maximum values, the current dominant control loop is determined in the order of combustion control loop, water supply control loop, and desuperheating control loop, and the target control amount of the corresponding actuator is determined.

8. The adaptive adjustment method for steam boilers under multiple operating conditions according to claim 2, characterized in that, S5 includes: Obtain the actual action of the actuator, as well as the adjusted steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature, and flue gas oxygen content; Based on the actual action of the actuator and the adjusted steam pressure, steam drum water level, steam flow rate, feedwater flow rate, main steam temperature and flue gas oxygen content, update the remaining influence quantities in the heating lag influence quantity storage area, the steam and water volume virtual change influence quantity storage area and the heat storage and release influence quantity storage area. Determine the updated current operating conditions based on the updated operating parameters; The corresponding attenuation coefficient is re-determined based on the updated current operating conditions.

9. An adaptive control system for steam boilers operating under multiple conditions, characterized in that: include: The parameter acquisition module is used to acquire the operating parameters of the steam boiler and the action parameters of the actuators, and to determine the current operating condition based on the operating parameters. The impact quantity management module is used to construct a storage area for the impact quantity of heating lag, the impact quantity of steam and water volume change, and the impact quantity of heat storage and release corresponding to the current operating condition based on the current operating condition and the recent actuator action parameters. When the operating condition switching boundary is detected, the remaining impact quantity in the impact quantity storage area corresponding to the previous operating condition is retained and transferred to the impact quantity storage area corresponding to the current operating condition according to the attenuation coefficient corresponding to the current operating condition. The correction module is used to perform lag effect correction on the current operating parameters based on the heating lag effect storage area, the steam-water volume change effect storage area, and the heat storage and release effect storage area, to obtain the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation. The adjustment decision module is used to determine the current dominant adjustment loop based on the corrected steam pressure deviation, the corrected steam drum water level deviation, and the corrected main steam temperature deviation, and to determine the target adjustment amount of the actuator corresponding to the current dominant adjustment loop; The execution update module is used to control the corresponding actuator of the steam boiler to adjust according to the target adjustment amount of the actuator, and update the heat supply lag effect storage area, the steam-water volume change effect storage area and the heat storage and release effect storage area according to the adjusted operating parameters.

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