A self-adaptive control method for multi-channel integrated monitoring of boiler water quality

Abstract

The present application relates to the field of industrial control technology, disclose a kind of boiler water quality multi-channel integrated monitoring self-adaptive control method, comprising: first, the space transmission lag time and phase change evaporation mass flow rate are measured by the system parameters obtained;Further, the distorted concentration obtained by multi-channel sensor is distorted and peeled off, and the real solute concentration of microcosmic liquid film is reconstructed;Then, the mass conservation continuous state equation containing hidden precipitation flow rate is established, and the change rate of bulk phase concentration is calculated and predicted;On this basis, the total energy consumption is minimized as the goal, and the optimal blowdown and dosing mass flow rate is generated by using non-parametric particle swarm algorithm iterative optimization;Finally, the blowdown valve opening degree instruction is converted by reverse mapping, and the truncated flow rate exceeding mechanical limit is fed forward to the system total water body equivalent mass for closed-loop update.The present application effectively decouples the space-time dislocation of water quality monitoring, and guarantees the accuracy and low energy consumption of water quality control under variable working conditions.

Description

Technical Field

[0001] This invention relates to the field of industrial control technology, and more specifically, to an adaptive control method for multi-channel integrated monitoring of boiler water quality. Background Technology

[0002] In the conventional operation of high-pressure natural circulation drum boilers, water quality monitoring and control typically rely on multi-channel sensors installed in the water phase region of the drum to read macroscopic water concentrations (such as conductivity and silicate). However, under actual high-load variable operating conditions, a strong boiling phase transition occurs within the water-cooled wall tubes, causing water to vaporize instantaneously. Salt ions remain trapped in the residual micron-sized liquid film adhering to the tube wall and precipitate in large quantities, creating a salt hiding effect. At this time, the salts free in the water adhere to the tube wall, and the mainstream water flowing back to the drum becomes purer, causing the concentration values ​​measured by the multi-channel sensors to not only fail to increase but also exhibit a false sharp drop. Only when the heat load decreases do the salts on the tube wall redissolve and return to the water, resulting in a delayed spike in sensor readings. Most existing automated control systems rely directly on these apparent concentration readings for feedback control, without addressing the underlying spatiotemporal phase shift hysteresis and nonlinear distortion. This makes it easy for the control system to erroneously stop adding chemicals during high-load periods when the risk of scaling is highest due to low readings, or to perform excessive discharge during low-load periods due to lagging readings. This makes it difficult to balance equipment safety with the conservation of water resources and thermal energy. Summary of the Invention

[0003] This invention provides an adaptive control method for multi-channel integrated monitoring of boiler water quality, which solves the technical problems mentioned in the background art.

[0004] This invention provides an adaptive control method for multi-channel integrated monitoring of boiler water quality, applied to a high-pressure natural circulation drum boiler. The high-pressure natural circulation drum boiler includes an economizer, a steam drum, downcomers, water-cooled walls, multi-channel water quality sensors, and a blowdown valve, configured to execute: Acquire initial system parameters, which include at least the distortion mass fraction, the equivalent mass of the total water volume in the system, and the limiting solubility obtained by the multi-channel water quality sensor; Based on the total mass of liquid water in the water-cooled wall and the mass flow rate of circulating water in the downcomer, the spatial transport lag time is estimated. The phase change evaporation mass flow rate is calculated based on the latent heat of vaporization corresponding to the absorbed heat power and the real-time steam drum pressure. By combining the spatial transport hysteresis time with the phase change evaporation mass flow rate, the distortion mass fraction is stripped to reconstruct the true solute mass fraction of the microscopic liquid film. A mass conservation continuous state equation is constructed, which includes the hidden precipitation rate driven by the actual solute mass fraction of the microscopic liquid film, and the rate of change of the predicted bulk concentration is calculated. An evaluation functional was constructed with the goal of minimizing total energy consumption. The parameterless particle swarm optimization algorithm was used for iterative optimization to generate the optimal sewage discharge mass flow rate and the optimal chemical dosing mass flow rate. Using inverse mapping, the optimal sewage mass flow rate is converted into the sewage valve opening command of the sewage valve; Extract the cut-off mass flow rate that exceeds the mechanical limit of the drain valve and feed it forward to the equivalent mass of the total water volume of the system for closed-loop update.

[0005] The beneficial effects of this invention are as follows: This invention dynamically decouples the spatiotemporal lag and nonlinear concentration distortion of multi-channel water quality monitoring caused by the hidden boiling and re-dissolution effects in the pipe. By reconstructing the real microscopic liquid film state through the mass conservation state equation and the parameterless algorithm, and issuing control commands, it avoids the risk of pipe wall scaling caused by the actuator blindly stopping the drug due to the interference of the false drop in sensor readings during the high load period. At the same time, it prevents the energy waste caused by excessive sewage discharge due to the lag surge in readings during the low load period, and achieves an effective balance between system operation safety and energy consumption under variable load conditions. Attached Figure Description

[0006] Figure 1 This is a flowchart of an adaptive control method for multi-channel integrated monitoring of boiler water quality according to the present invention. Detailed Implementation

[0007] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0008] like Figure 1 As shown, an adaptive control method for multi-channel integrated monitoring of boiler water quality is applied to a high-pressure natural circulation drum boiler. The high-pressure natural circulation drum boiler includes an economizer, a drum, downcomers, water-cooled walls, multi-channel water quality sensors, and blowdown valves. The multi-channel water quality sensors are installed in the bulk water region near the continuous blowdown outlet at the bottom of the drum. All acquisition terminals use the NTP network time protocol for clock synchronization to ensure that the time synchronization error does not exceed 10% of the sampling period, and the sampling period of all parameters remains consistent.

[0009] Obtain initial system parameters, which should include at least the distortion mass fraction, the equivalent mass of the total water volume in the system, and the limiting solubility obtained from the multi-channel water quality sensor.

[0010] The distortion mass fraction is the solute mass fraction collected by the multi-channel water quality sensor in the water phase region of the steam drum. It is a dimensionless parameter, and the sampling period can be set from 1 second to 1 minute. It is synchronously collected through industrial common data transmission protocols such as Modbus, OPC UA, and HTTP / HTTPS.

[0011] The equivalent mass of the total water volume in the system is the total mass of all liquid water in the boiler system, in kilograms. The initial value is calculated using boiler design parameters and is equal to the sum of the steam drum water volume, the downcomer water volume, and the water-cooled wall water volume multiplied by the saturated water density at the current steam drum pressure. It will be dynamically updated in the future.

[0012] Limiting solubility is the saturated mass fraction of the solute at the current steam drum pressure and temperature. It is a dimensionless parameter and is obtained by calling the IAPWS-IF97 standard thermodynamic database or the national industrial boiler water quality standard database.

[0013] When the system starts up, the initial predicted bulk concentration is taken from the distorted mass fraction collected for the first time by the multi-channel water quality sensor.

[0014] Obtain the total mass of liquid water in the water-cooled wall and the mass flow rate of circulating water in the downcomer. The total mass of liquid water in the water-cooled wall is the mass of all liquid water in the water-cooled wall tubes, in kilograms. It is calculated using boiler design parameters and is equal to the cross-sectional area of ​​a single water-cooled wall tube multiplied by the total length of the water-cooled wall tubes, then multiplied by the number of water-cooled wall tubes, and finally multiplied by the saturated water density at the current steam drum pressure.

[0015] The mass flow rate of the circulating water in the downcomer is the instantaneous mass flow rate of the circulating water in the downcomer, expressed in kilograms per second. It is collected by an electromagnetic flowmeter installed on the downcomer, and the sampling period is consistent with that of the multi-channel water quality sensor.

[0016] Dividing the total mass of liquid water in the water-cooled wall by the mass flow rate of the circulating water in the downcomer yields the spatial transport lag time, which specifically satisfies the following formula: in, The spatial transport lag time, in seconds, characterizes the time required for the working fluid inside the water-cooled wall to flow from the heated surface back to the steam drum. This represents the total mass of liquid water in the water-cooled wall. The mass flow rate of the circulating water in the downcomer; It is a time variable.

[0017] The absorbed heat power of the water-cooled wall in real time and the latent heat of vaporization of water and steam under real-time steam drum pressure are obtained.

[0018] The absorbed heat power is the heat absorbed by the water-cooled wall per unit time, measured in kilowatts (kW), and can be obtained in two ways. The first method is to calculate it using the enthalpy difference between the inlet and outlet of the water-cooled wall, using the formula: ,in The specific enthalpy of the working fluid at the water-cooled wall inlet. The specific enthalpy of the working fluid at the water-cooled wall outlet is calculated by combining the enthalpy of saturated water and saturated steam under the current steam drum pressure with the cycle ratio. The second method calculates it using the total boiler input heat power, which equals the fuel mass flow rate multiplied by the fuel lower heating value multiplied by the boiler thermal efficiency, and then multiplied by the water-cooled wall heat absorption ratio. The water-cooled wall heat absorption ratio is determined by the boiler design parameters and is typically between 0.7 and 0.9.

[0019] The latent heat of vaporization is the amount of heat required for a unit mass of water to completely vaporize under the current steam drum pressure, expressed in kilojoules per kilogram, and obtained by accessing the IAPWS-IF97 standard thermodynamic database.

[0020] Dividing the absorbed heat power by the latent heat of vaporization yields the phase change evaporation mass flow rate, which specifically satisfies the following formula: in, The phase change evaporation mass flow rate is expressed in kilograms per second, which characterizes the mass of water evaporated into steam within the water-cooled wall per unit time. To absorb heat power; Real-time steam drum pressure, in Pascals; This represents the latent heat of vaporization corresponding to the real-time steam drum pressure.

[0021] Calculate the rate of change of distortion quality fraction with respect to time to obtain the rate of change of distortion quality fraction.

[0022] For discrete sampled data, the first derivative is approximated using the first-order forward difference method, and the formula is: in, The rate of change of the distortion mass fraction is expressed in seconds. The distortion quality score at the current moment; This represents the distortion quality score at the previous sampling time. The sampling period is expressed in seconds.

[0023] Divide the mass flow rate of the downcomer circulating water by the difference between it and the mass flow rate of the phase change evaporation to obtain the dilution-reduction multiplier.

[0024] The dilution-reduction multiplier is a dimensionless parameter used to correct for the bulk water dilution effect caused by phase change evaporation. Its calculation formula is as follows: in, This is for diluting and reducing multipliers.

[0025] Multiplying the spatial transmission hysteresis time by the rate of change of distortion quality fraction yields the timing compensation term.

[0026] The timing compensation term is a dimensionless parameter used to correct timing misalignments caused by spatial transmission hysteresis. Its calculation formula is as follows: in, This is a timing compensation term.

[0027] Adding the product of the distortion mass fraction and the dilution-reduction multiplier with a sequential compensation term yields the true solute mass fraction of the microscopic liquid film, which satisfies the following formula: in, is the true mass fraction of solute in the microscopic liquid film, a dimensionless parameter that characterizes the actual mass fraction of solute in the micrometer-scale liquid film closely adhering to the water-cooled tube wall.

[0028] Obtain historical offset parameters and current flow rate parameters. Historical offset parameters include the historical microscopic liquid film true solute mass fraction and historical phase change evaporation mass flow rate corresponding to the offset space transmission hysteresis time. Current flow rate parameters include the current feed water mass flow rate, feed water concentration, current dosing mass flow rate, chemical purity, current sewage discharge mass flow rate, and current predicted bulk concentration.

[0029] The true solute mass fraction of the historical microscopic liquid film is The actual solute mass fraction of the microscopic liquid film at any given time, and the historical phase change evaporation mass flow rate. The phase change evaporation mass flow rate at each moment is stored in the system's historical data buffer, and the buffer length is not less than the number of sampling points corresponding to the maximum possible spatial transmission lag time.

[0030] The current feedwater mass flow rate is the instantaneous mass flow rate of feedwater entering the boiler, measured in kilograms per second, and is collected by an electromagnetic flow meter installed on the feedwater pipeline.

[0031] The water concentration is the mass fraction of the solute in the water, which is a dimensionless parameter and is collected by a water quality sensor installed on the water supply pipeline.

[0032] The current dosing mass flow rate is the instantaneous mass flow rate of the liquid medicine output by the dosing pump, expressed in kilograms per second, and is obtained through the flow feedback signal of the dosing pump.

[0033] The purity of the drug solution is the mass fraction of the effective solute in the drug solution. It is a dimensionless parameter, an inherent parameter of the drug, and is provided by the drug supplier.

[0034] The current sewage discharge mass flow rate is the instantaneous mass flow rate of sewage discharged from the sewage discharge valve, expressed in kilograms per second. It is collected by an electromagnetic flow meter installed on the sewage discharge pipeline or calculated based on the opening degree of the sewage discharge valve.

[0035] The current predicted bulk concentration is the mass fraction of solute in the steam drum calculated in the previous cycle, which is a dimensionless parameter.

[0036] The hidden precipitation flow rate is obtained by dividing the square of the true solute mass fraction of the historical microfilm by the limiting solubility and then multiplying it by the historical phase change evaporation mass flow rate.

[0037] The hidden precipitation flow rate is the mass flow rate of solute precipitated from the microscopic liquid film and adhering to the pipe wall per unit time, expressed in kilograms per second. Its calculation formula is: in, To conceal the precipitation rate; The limiting solubility is given by the formula. This formula is based on the classical nucleation theory of crystallization kinetics. The solute precipitation rate is proportional to the square of the supersaturation, which is the ratio of the actual mass fraction of solute in the microscopic liquid film to the limiting solubility. Therefore, the hidden precipitation flow rate is proportional to the square of the actual mass fraction of solute in the microscopic liquid film and inversely proportional to the limiting solubility.

[0038] The feedwater solute flow rate is obtained by multiplying the current feedwater mass flow rate by the feedwater concentration; the dosing solute flow rate is obtained by multiplying the current dosing mass flow rate by the drug purity; and the discharge solute flow rate is obtained by multiplying the current discharge mass flow rate by the current predicted bulk concentration.

[0039] The feedwater solute flow rate is the mass of solute entering the system with the feedwater per unit time, expressed in kilograms per second.

[0040] The solute flow rate is the effective solute mass entering the system with the drug solution per unit time, expressed in kilograms per second.

[0041] The solute flow rate of the wastewater is the mass of solute discharged from the system per unit time, expressed in kilograms per second.

[0042] Add the feedwater solute flow rate to the chemical dosing solute flow rate, subtract the wastewater solute flow rate and the hidden precipitation flow rate, and then divide by the current total equivalent mass of the system water to obtain the predicted rate of change of the bulk concentration, which satisfies the following formula: in, To predict the rate of change of bulk concentration, the unit is per second; This represents the current water supply mass flow rate; For water concentration; The current drug delivery flow rate; For the purity of the drug solution; The current sewage discharge quality flow rate; This is the current predicted bulk concentration; This represents the current equivalent mass of the total water volume in the system.

[0043] The control integral parameters and algorithm initial parameters are obtained. The control integral parameters include the wastewater flow rate integral variable, the wastewater sensible heat specific enthalpy, the chemical dosing flow rate integral variable, the equivalent manufacturing potential of the chemical, the evaporation flow rate integral variable, the latent heat of vaporization integral variable, and the predicted bulk concentration integral variable. The algorithm initial parameters include the initialized current particle swarm velocity and current particle swarm position, the individual optimal position, the global optimal position, and the first random number and the second random number.

[0044] The sewage flow rate integral variable is a time function of the predicted sewage mass flow rate in the time domain, with units of kilograms per second.

[0045] The sensible heat specific enthalpy of the wastewater is the specific enthalpy of saturated water at the current steam drum pressure, expressed in kilojoules per kilogram, and obtained from the IAPWS-IF97 standard thermodynamic database.

[0046] The drug delivery flow rate integral variable is a time function of the drug delivery mass flow rate in the prediction time domain, with units of kilograms per second.

[0047] The equivalent manufacturing potential of a pharmaceutical agent is the energy consumed to produce a unit mass of pharmaceutical agent, expressed in kilojoules per kilogram. It is a common industrial parameter and can be obtained by consulting industry standard databases based on the type of pharmaceutical agent.

[0048] The evaporation flow rate integral variable is a time function of the phase change evaporation mass flow rate in the prediction time domain, and its unit is kilograms per second.

[0049] The latent heat of vaporization integral variable is a time function of the latent heat of vaporization in the prediction time domain, and the unit is kilojoules per kilogram.

[0050] The integral variable for predicting bulk concentration is a time function of the predicted bulk concentration within the prediction time domain, and is a dimensionless parameter.

[0051] The number of particles in a particle swarm is typically set to 20 to 50, and can be adjusted according to the required optimization accuracy. The current particle swarm velocity is the particle's movement speed within the optimization space. Each particle corresponds to a combination of sewage discharge and chemical dosing mass flow rates, initialized to a range within... The random value is expressed in kilograms per second per iteration. The current particle swarm position is the particle's coordinate in the optimization space, i.e., the current test's wastewater discharge and chemical dosing mass flow rate values, initialized to random values ​​within a reasonable range. The wastewater discharge mass flow rate range is... The dosing flow rate range is: ,in This represents the maximum discharge flow rate of the drain valve. The values ​​represent the maximum dosing flow rate of the dosing pump, all in kilograms per second.

[0052] The individual optimal position is the position where each particle achieves the minimum total energy consumption in the iteration history, initialized to the particle's initial position. The global optimal position is the position where the entire particle swarm achieves the minimum total energy consumption in the iteration history, initialized to the position with the minimum objective functional value among all particle initial positions.

[0053] First random number Second random number The range of values ​​is Uniformly distributed random numbers are generated and regenerated in each iteration.

[0054] The boundary handling rules for particle positions are as follows: when the updated particle position is less than 0, it is set to 0; when the updated sewage discharge mass flow rate is greater than the theoretical maximum sewage discharge flow rate, the theoretical maximum sewage discharge flow rate is used; when the updated dosing mass flow rate is greater than the dosing pump's maximum dosing flow rate, the dosing pump's maximum dosing flow rate is used.

[0055] The total energy consumption objective functional is obtained by summing the products of the wastewater flow rate integral variable and the wastewater sensible enthalpy, the chemical dosing flow rate integral variable and the equivalent manufacturing potential of the chemical, and the combined products of the evaporation flow rate integral variable, the latent heat of vaporization integral variable, the predicted bulk concentration integral variable, and the square of the limiting solubility quotient. This summation is then performed over the prediction time domain. in, The target functional represents the total energy consumption, expressed in kilojoules. For prediction in the time domain, the unit is seconds, typically set to 60 to 600 seconds; For integration time; The sensible heat specific enthalpy of the sewage discharge; This provides the potential for equivalent manufacturing of pharmaceutical agents. For discrete sampled data, this integral can be approximated using the trapezoidal integral method.

[0056] Using the natural constant as the base and the quotient of the negative current phase change evaporation mass flow rate and the downcomer circulating water mass flow rate as the exponent, the dynamic inertia weight is calculated using the following formula: in, The dynamic inertia weight is a dimensionless parameter used to balance the algorithm's global exploration capability and local exploitation capability.

[0057] Adding constant 1 to the quotient of the current predicted bulk concentration and the limiting solubility, we obtain the adaptive cognitive factor, which is calculated using the following formula: in, is an adaptive cognitive factor, and is a dimensionless parameter.

[0058] Add the constant 1 to the quotient of the current feedwater mass flow rate and the downcomer circulating water mass flow rate to obtain the adaptive social factor, the formula of which is: in, is an adaptive social factor, and is a dimensionless parameter.

[0059] Multiply the current particle swarm velocity by the dynamic inertia weight, add the product of the adaptive cognitive factor, the first random number, and the difference between the individual's optimal position and the current particle swarm position, and add the product of the adaptive social factor, the second random number, and the difference between the global optimal position and the current particle swarm position to obtain the updated particle swarm velocity. Update the particle swarm position, and output the optimal sewage discharge mass flow rate and optimal chemical dosing mass flow rate corresponding to the objective functional that minimizes the total energy consumption. The iterative update process specifically satisfies the following formula: in, The updated particle swarm velocity; The current particle swarm velocity; This represents the current position of the particle swarm. The optimal position for the individual; The globally optimal position; The updated particle swarm position; the optimal sewage mass flow rate is denoted as... The unit is kilograms per second; the optimal dosing mass flow rate is denoted as... The unit is kilograms per second.

[0060] During the iteration process, the total energy consumption objective functional value of all particles is calculated each time. If the objective functional value of the current particle is less than its individual optimal value, the individual optimal position of the particle is updated; if the minimum objective functional value of all particles is less than the global optimal value, the global optimal position is updated. The convergence conditions include reaching a preset maximum of 200 iterations, the relative change of the global optimal objective functional value over 10 consecutive iterations being less than 1e-3, or the standard deviation of the particle swarm positions being less than 1e-4. The iteration terminates when any one of these conditions is met.

[0061] Obtain the full-open flow cross-sectional area of ​​the drain valve, the saturated water density, the current internal pressure of the steam drum, and the ambient back pressure.

[0062] The fully open flow cross-sectional area of ​​the drain valve is the flow cross-sectional area when the drain valve is fully open, in square meters. It is an inherent parameter of the drain valve and is provided by the valve supplier.

[0063] The density of saturated water is the density of saturated water at the current steam drum pressure, expressed in kilograms per cubic meter, obtained from the IAPWS-IF97 standard thermodynamic database.

[0064] The current pressure inside the steam drum is the real-time pressure inside the steam drum, measured in Pascals, and is collected by a pressure sensor installed on the steam drum.

[0065] Ambient back pressure is the ambient pressure at the outlet of the drain valve, measured in Pascals, typically 101325 Pascals (standard atmosphere).

[0066] The theoretical maximum sewage flow rate is obtained by multiplying the difference between the current steam drum internal pressure and the ambient back pressure by a constant 2 and the saturated water density, taking the square root, and then multiplying by the flow cross-sectional area of ​​the fully open drain valve. The calculation formula is as follows: in, This represents the theoretical maximum sewage flow rate, expressed in kilograms per second. The full opening flow cross-sectional area of ​​the drain valve; This is the density of saturated water; This is the current internal pressure of the steam drum; For environmental back pressure.

[0067] Dividing the optimal sewage flow rate by the theoretical maximum sewage flow rate converts it into a sewage valve opening command, which specifically satisfies the following formula: in, This is the drain valve opening command, a dimensionless parameter. The boundary handling rule for the drain valve opening command is that when the calculated value is... When less than 0, take 0; when When the value is greater than 1, it is taken as 1. 0 indicates that the drain valve is completely closed, and 1 indicates that the drain valve is completely open.

[0068] Obtain the operation cycle step size of the control system.

[0069] The operation cycle step size is the time interval between the control system executing a complete control logic operation, measured in seconds, and is typically set to 1 to 10 seconds.

[0070] The difference between the drain valve opening command and the constant 1 is compared with the constant zero, and the maximum value is taken. This maximum value is then multiplied by the theoretical maximum drain flow rate to obtain the cut-off mass flow rate that could not be discharged due to mechanical limitations, which specifically satisfies the following formula: in, The mass flow rate is cutoff, expressed in kilograms per second.

[0071] Add the optimal dosing flow rate and the cutoff flow rate to the current feedwater flow rate, and subtract the optimal wastewater discharge flow rate and the phase change evaporation flow rate to obtain the system's net mass flow rate. The calculation formula is as follows: in, The system's net mass change rate is expressed in kilograms per second.

[0072] Multiply the system's net mass change rate by the calculation cycle step size and add it to the current system's total water equivalent mass to obtain the updated system's total water equivalent mass for the next cycle, specifically satisfying the following formula: in, This is the step size of the computation cycle; The updated equivalent mass of the total system water volume for the next cycle is used. The boundary treatment rule for the updated equivalent mass of the total system water volume is as follows: when the updated equivalent mass of the total system water volume is less than the minimum allowable water mass of the boiler, the minimum allowable water mass of the boiler is used. The minimum allowable water mass of the boiler is determined by the boiler design parameters and is the water mass corresponding to the lowest safe liquid level in the steam drum. The updated equivalent mass of the total system water volume will be used to calculate the predicted volumetric concentration change rate for the next cycle, achieving closed-loop control.

[0073] The embodiments of this example have been described above. However, this example is not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms based on the guidance of this example, and all of them are within the protection scope of this example.

Claims

1. An adaptive control method for multi-channel integrated monitoring of boiler water quality, applied to a high-pressure natural circulation drum boiler, wherein the high-pressure natural circulation drum boiler includes an economizer, a steam drum, downcomers, water-cooled walls, multi-channel water quality sensors, and a blowdown valve, characterized in that, Configured for execution: Acquire initial system parameters, which include at least the distortion mass fraction, the equivalent mass of the total water volume in the system, and the limiting solubility obtained by the multi-channel water quality sensor; Based on the total mass of liquid water in the water-cooled wall and the mass flow rate of circulating water in the downcomer, the spatial transport lag time is estimated. The phase change evaporation mass flow rate is calculated based on the latent heat of vaporization corresponding to the absorbed heat power and the real-time steam drum pressure. By combining the spatial transport hysteresis time with the phase change evaporation mass flow rate, the distortion mass fraction is stripped to reconstruct the true solute mass fraction of the microscopic liquid film. A mass conservation continuous state equation is constructed, which includes the hidden precipitation rate driven by the actual solute mass fraction of the microscopic liquid film, and the rate of change of the predicted bulk concentration is calculated. An evaluation functional was constructed with the goal of minimizing total energy consumption. The parameterless particle swarm optimization algorithm was used for iterative optimization to generate the optimal sewage discharge mass flow rate and the optimal chemical dosing mass flow rate. Using inverse mapping, the optimal sewage mass flow rate is converted into the sewage valve opening command of the sewage valve; Extract the cut-off mass flow rate that exceeds the mechanical limit of the drain valve and feed it forward to the equivalent mass of the total water volume of the system for closed-loop update.

2. The adaptive control method for multi-channel integrated monitoring of boiler water quality according to claim 1, characterized in that, The calculation of spatial transport lag time based on the total mass of liquid water in the water-cooled wall and the mass flow rate of circulating water in the downcomer includes: Obtain the total mass of liquid water in the water-cooled wall and the mass flow rate of circulating water in the downcomer; The spatial transport hysteresis time is obtained by dividing the total mass of liquid water in the water-cooled wall by the mass flow rate of the circulating water in the downcomer.

3. The adaptive control method for multi-channel integrated monitoring of boiler water quality according to claim 2, characterized in that, The calculation of the phase change evaporation mass flow rate based on the latent heat of vaporization corresponding to the absorbed heat power and the real-time steam drum pressure includes: The absorbed heat power of the water-cooled wall in real time and the latent heat of vaporization of water and steam under the real-time steam drum pressure are obtained. The phase change evaporation mass flow rate is obtained by dividing the absorbed heat power by the latent heat of vaporization.

4. The adaptive control method for multi-channel integrated monitoring of boiler water quality according to claim 3, characterized in that, The step of combining the spatial transport hysteresis time and the phase change evaporation mass flow rate to perform distortion stripping on the distorted mass fraction and reconstruct the true solute mass fraction of the microscopic liquid film includes: Calculate the rate of change of the distortion quality fraction with respect to time to obtain the distortion quality fraction change rate; Divide the mass flow rate of the downcomer circulating water by the difference between it and the mass flow rate of the phase change evaporation to obtain the dilution-reduction multiplier; Multiply the spatial transmission hysteresis time by the rate of change of the distortion quality fraction to obtain the timing compensation term; The product of the distortion mass fraction and the dilution-reduction multiplier is added to the time-compensation term to obtain the true solute mass fraction of the microscopic liquid film.

5. The adaptive control method for multi-channel integrated monitoring of boiler water quality according to claim 4, characterized in that, The construction of the mass conservation continuous state equation, which includes the hidden precipitation flow rate driven by the true solute mass fraction of the microscopic liquid film, and the calculation of the predicted rate of change of bulk concentration, includes: The historical offset parameters and current flow rate parameters are obtained. The historical offset parameters include the historical true solute mass fraction of the microscopic liquid film and the historical phase change evaporation mass flow rate corresponding to the offset of the spatial transport hysteresis time. The current flow rate parameters include the current feed water mass flow rate, feed water concentration, current dosing mass flow rate, chemical purity, current sewage discharge mass flow rate, and current predicted bulk concentration. The hidden precipitation flow rate is obtained by dividing the square of the true solute mass fraction of the historical microscopic liquid film by the limiting solubility and then multiplying it by the historical phase change evaporation mass flow rate. The feedwater solute flow rate is obtained by multiplying the current feedwater mass flow rate by the feedwater concentration; the dosing solute flow rate is obtained by multiplying the current dosing mass flow rate by the drug purity; and the discharge solute flow rate is obtained by multiplying the current discharge mass flow rate by the current predicted bulk concentration. The predicted rate of change of bulk concentration is obtained by adding the feed water solute flow rate and the dosing solute flow rate, subtracting the discharge solute flow rate and the hidden precipitation flow rate, and then dividing by the current equivalent mass of the total water body of the system.

6. The adaptive control method for multi-channel integrated monitoring of boiler water quality according to claim 5, characterized in that, The process involves constructing an evaluation functional with the goal of minimizing total energy consumption, and using a parameter-free particle swarm optimization algorithm for iterative optimization to generate the optimal wastewater discharge mass flow rate and the optimal chemical dosing mass flow rate, including: The control integral parameters and algorithm initial parameters are obtained. The control integral parameters include the wastewater flow rate integral variable, the wastewater sensible heat specific enthalpy, the chemical dosing flow rate integral variable, the equivalent manufacturing potential of the chemical, the evaporation flow rate integral variable, the latent heat of vaporization integral variable, and the predicted bulk concentration integral variable. The algorithm initial parameters include the initialized current particle swarm velocity and current particle swarm position, the individual optimal position, the global optimal position, and the first random number and the second random number. The product of the wastewater flow rate integral variable and the wastewater sensible heat specific enthalpy, the product of the dosing flow rate integral variable and the equivalent manufacturing potential of the agent, and the product of the evaporation flow rate integral variable, the latent heat of vaporization integral variable, the predicted bulk concentration integral variable, and the square of the limiting solubility quotient are summed and integrated over time in the prediction time domain to obtain the total energy consumption objective functional. The dynamic inertial weight is calculated using the natural constant as the base and the quotient of the negative current phase change evaporation mass flow rate and the downcomer circulating water mass flow rate as the exponent. Add constant 1 to the quotient of the current predicted bulk concentration and the limiting solubility to obtain the adaptive cognitive factor; Add the constant 1 to the quotient of the current feedwater mass flow rate and the downcomer circulating water mass flow rate to obtain the adaptive social factor; The current particle swarm velocity is multiplied by the dynamic inertia weight, and then the product of the adaptive cognitive factor, the first random number, and the difference between the individual optimal position and the current particle swarm position is added. Finally, the product of the adaptive social factor, the second random number, and the difference between the global optimal position and the current particle swarm position is added to obtain the updated particle swarm velocity. The particle swarm position is then updated, and the optimal sewage discharge mass flow rate and the optimal chemical dosing mass flow rate corresponding to the objective functional that minimizes the total energy consumption are output.

7. The adaptive control method for multi-channel integrated monitoring of boiler water quality according to claim 6, characterized in that, The process of using inverse mapping to convert the optimal sewage mass flow rate into a sewage valve opening command includes: Obtain the full-open flow cross-sectional area of ​​the drain valve, the saturated water density, the current internal pressure of the steam drum, and the ambient back pressure; Multiply the difference between the current steam drum internal pressure and the ambient back pressure by a constant and the saturated water density, take the square root, and then multiply by the full-open flow cross-sectional area of ​​the drain valve to obtain the theoretical maximum drain flow rate. Divide the optimal sewage flow rate by the theoretical maximum sewage flow rate to convert it into the sewage valve opening command.

8. The adaptive control method for multi-channel integrated monitoring of boiler water quality according to claim 7, characterized in that, The extraction of the cutoff mass flow rate exceeding the mechanical limit of the drain valve, and its feedforward to the equivalent mass of the total water volume in the system for closed-loop updating, includes: Obtain the operation cycle step size of the control system; The difference obtained by subtracting a constant from the opening command of the drain valve is compared with the constant zero and the maximum value is taken. This value is then multiplied by the theoretical maximum drain flow rate to obtain the cut-off mass flow rate that failed to be discharged due to mechanical limitations. Add the current water supply mass flow rate to the optimal dosing mass flow rate and the cutoff mass flow rate, and subtract the optimal sewage discharge mass flow rate and the phase change evaporation mass flow rate to obtain the system net mass change rate; The net mass change rate of the system is multiplied by the operation cycle step size and added to the current equivalent mass of the total water body of the system to obtain the updated equivalent mass of the total water body of the system for the next cycle.

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