A parameter adaptive optimization control method of a carrier gas evaporation condenser

Abstract

This invention belongs to the field of automatic control technology, specifically relating to a parameter adaptive optimization control method for a carrier gas evaporator-condenser. The method includes: acquiring and denoising the inlet carrier gas temperature, outlet carrier gas temperature, inlet carrier gas volumetric flow rate, inlet carrier gas relative humidity, and real-time spray water flow rate to obtain an effective operating dataset; acquiring the instantaneous heat transfer power at the sampling time based on the effective operating dataset; obtaining the evaporation efficiency ratio coefficient based on the instantaneous heat transfer power; acquiring the adaptive control gain based on the deviation between the evaporation efficiency ratio coefficient and a preset benchmark efficiency coefficient; compensating for the pressure deviation value of the condensing pressure using the adaptive control gain; and acquiring and issuing target frequency commands to the variable frequency drive devices for the fan and the spray water circulation pump. This invention solves the problem that control parameters cannot be dynamically adjusted according to environmental load, reduces energy consumption, and improves the stability of condensing pressure control.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology. More specifically, this invention relates to a parameter adaptive optimization control method for a carrier gas evaporator-condenser. Background Technology

[0002] As a core controlled component of industrial thermal management systems, the stability and heat exchange efficiency of carrier gas evaporative condensers directly determine the energy efficiency and product quality of the entire process. In the field of automatic control technology, establishing accurate control models and achieving real-time adaptive parameter adjustment for such controlled objects with complex physical characteristics has always been a key research direction in industrial automation. Currently, the control logic of carrier gas evaporative condensers generally adopts a pre-set fixed parameter adjustment method, that is, based on the initial design conditions and calibration results of the controlled object, fixed proportional-integral-derivative control parameters or logic gains are set for actuators such as fans and spray water circulation pumps. However, in actual industrial production sites, the operating environment of carrier gas evaporative condensers is constantly evolving, and their controlled process exhibits strong time-varying and nonlinear characteristics. Due to the influence of upstream process fluctuations on the load on the carrier gas side, the temperature and volumetric flow rate of the inlet carrier gas will frequently change. At the same time, the ambient humidity and temperature of the external atmosphere will directly interfere with the dynamic balance of condensing pressure through thermal convection and moisture evaporation mechanisms.

[0003] In this complex physical environment with multiple variables, traditional fixed-parameter control systems often struggle to exhibit ideal adaptability. When production loads shift significantly, the control gain, originally tuned under standard operating conditions, gradually becomes inaccurate, leading to a noticeable lag or overcompensation between the controller's commands and the actual cooling requirements of the controlled object. Industrial heat exchange processes often exhibit significant inertia. The carrier gas evaporator-condenser requires a long response time from receiving a frequency adjustment signal to the final stabilization of the condensing pressure. Existing control technologies typically lack real-time identification of internal physical processes and cannot perceive the evaporation contribution of the water film on the outer wall of the heat exchange tube bundle under different temperature and humidity conditions. This forces the control system to rely on error-driven feedback adjustment when facing complex disturbances, rather than actively correcting parameters based on the system's current physical performance. This can easily lead to fans operating at high power output for extended periods or improper spray water volume adjustment, resulting in unnecessary energy losses and making it difficult to meet higher-standard process requirements for condensing pressure closed-loop accuracy.

[0004] With the increasing demands for intelligence in industrial control systems, how to achieve real-time perception of the thermodynamic characteristics of carrier gas evaporative condensers using operational data in the absence of precise mathematical models, and adjust the control intensity of the control algorithm accordingly, has become a key bottleneck in improving the economic efficiency and stability of equipment operation in this technical field. In existing system architectures, online optimization of control parameters generally faces problems such as severe data noise interference and a disconnect between physical mechanisms and control strategies, lacking a closed-loop mechanism that can directly convert the physical indicators of the heat exchange process into control gain correction quantities. Due to the inability to accurately assess the evaporation efficiency level of the controlled object at the current moment, the controller's adjustment actions often lack specificity, making it difficult to achieve an ideal balance between meeting cooling requirements and reducing operating costs. Therefore, for such complex industrial controlled objects constrained by multiple time-varying factors, developing a control strategy that can adaptively optimize parameters based on real-time operational data streams has significant technical research value for ensuring the stable operation of carrier gas evaporative condensers. Summary of the Invention

[0005] To address the technical problem that traditional fixed-parameter control methods struggle to perceive the dynamic evolution of system thermal characteristics during the operation of carrier gas evaporative condensers due to real-time fluctuations in carrier gas load and ambient temperature and humidity, leading to a mismatch between actuator output power and actual cooling demand, resulting in increased energy loss and condensing pressure fluctuations, this invention provides a parameter adaptive optimization control method for carrier gas evaporative condensers. The method includes: acquiring inlet carrier gas temperature, outlet carrier gas temperature, inlet carrier gas volumetric flow rate, inlet carrier gas relative humidity, and real-time spray water flow rate, and performing data denoising and standardization to obtain an effective operating dataset; acquiring instantaneous heat transfer power based on the inlet carrier gas temperature, outlet carrier gas temperature, and inlet carrier gas volumetric flow rate in the effective operating dataset; acquiring an evaporation efficiency ratio coefficient based on the instantaneous heat transfer power and the real-time spray water flow rate in the effective operating dataset; acquiring an adaptive control gain based on the evaporation efficiency ratio coefficient and a preset benchmark efficiency coefficient; acquiring the pressure deviation between the measured and target values ​​of the condensing pressure; and acquiring the target frequency commands for the fan variable frequency drive and the spray water circulation pump variable frequency drive based on the pressure deviation and the adaptive control gain, thereby achieving carrier gas evaporative condenser control.

[0006] This invention obtains instantaneous heat transfer power by integrating physical signals from multiple dimensions such as inlet carrier gas temperature, outlet carrier gas temperature, and volumetric flow rate, and obtains the evaporation efficiency ratio coefficient by combining real-time spray water flow rate. This generates an adaptive control gain that changes with the environment, realizing dynamic adjustment of the target frequency commands of the variable frequency drive device for the fan and the variable frequency drive device for the spray water circulation pump. This reduces the mismatch between the output power of the actuator and the actual condensation load, and improves the operational stability of the carrier gas evaporator condenser under varying operating conditions.

[0007] Preferably, obtaining the effective operating dataset includes: converting the inlet carrier gas temperature, outlet carrier gas temperature, inlet carrier gas volumetric flow rate, inlet carrier gas relative humidity, and real-time spray water flow rate into analog voltage signals, and converting the analog voltage signals into discrete digital sequences by an analog-to-digital converter; using the discrete digital sequences as input, calculating the numerical difference between adjacent sampling points using a sliding window algorithm; and replacing the numerical difference with the average value of the preceding multiple sampling points when the numerical difference exceeds a preset coefficient of variation threshold, thereby obtaining the effective operating dataset.

[0008] This invention utilizes a sliding window algorithm to detect numerical differences in the collected discrete digital sequences and performs average value replacement on abnormal data that exceed the coefficient of variation threshold. This reduces the interference of sensor measurement noise on the effective operating dataset and improves the data foundation quality of subsequent adaptive adjustment logic.

[0009] Preferably, the instantaneous heat transfer power satisfies the expression: In the formula, express Instantaneous heat transfer power at any given moment; express The inlet carrier gas temperature at any given time; express The outlet carrier gas temperature at any given time; express The inlet carrier gas volumetric flow rate at any given time; Indicates the carrier gas density; This indicates the specific heat capacity of the carrier gas at constant pressure.

[0010] Based on the physical mechanism of heat exchange, this invention obtains instantaneous heat exchange power by measuring the numerical difference between the inlet and outlet carrier gas temperatures and the inlet carrier gas volumetric flow rate. It can provide real-time feedback on the dynamic trend of heat release on the carrier gas side, providing an objective physical benchmark for the system to perceive the real-time evolution of condensation load.

[0011] Preferably, the carrier gas density and the carrier gas specific heat capacity at constant pressure are obtained by: querying the aerodynamic standard property table to obtain the physical constant value of the carrier gas at the current working pressure, using the queried density constant as the carrier gas density, and using the queried specific heat capacity constant as the carrier gas specific heat capacity at constant pressure.

[0012] This invention obtains the carrier gas density and specific heat capacity at constant pressure by querying the aerodynamic standard property table, ensuring the accuracy of the physical property constants in the calculation of instantaneous heat transfer power under different pressure environments and reducing the load assessment error caused by parameter setting deviations.

[0013] Preferably, the evaporation efficiency ratio satisfies the following expression: In the formula, express The evaporation efficiency ratio coefficient at any given time; express Instantaneous heat transfer power at any given moment; express Real-time spray water flow rate; Indicates the density of water; It represents the latent heat of vaporization of water.

[0014] This invention obtains the evaporation efficiency ratio coefficient by calculating the ratio of instantaneous heat transfer power to the theoretical upper limit of spray water evaporation energy, thereby realizing real-time monitoring of the contribution of water evaporation to heat transfer and reducing the problem of control gain adjustment inaccuracy caused by the inability to assess the evaporation level under different ambient humidity conditions.

[0015] Preferably, the water density and the latent heat of vaporization of the water are obtained by: using a water vapor property table to obtain the saturated water density and latent heat of vaporization at the working temperature, taking the obtained saturated water density value as the water density, and taking the obtained latent heat of vaporization value as the latent heat of vaporization of the water.

[0016] This invention utilizes a water vapor property table to obtain the saturated water density and latent heat of vaporization at the current temperature, enabling the physical parameters required for calculating the evaporation efficiency ratio to be adjusted in real time with the operating temperature, thereby improving the scientific rigor of the heat transfer limit assessment.

[0017] Preferably, the adaptive control gain satisfies the expression: In the formula, express Adaptive control gain at any given time; express The evaporation efficiency ratio coefficient at any given time; This represents the preset baseline performance coefficient; Indicates the sensitivity coefficient; This represents the base gain offset.

[0018] This invention utilizes the deviation between the evaporation efficiency ratio coefficient and the benchmark efficiency coefficient, combined with the sensitivity coefficient, to obtain adaptive control gain. This allows the control system to self-correct its adjustment based on the current heat exchange efficiency, thereby enhancing the system's ability to compensate for environmental fluctuations.

[0019] Preferably, the sensitivity coefficient is obtained by collecting data on the change of the actuator frequency adjustment amount relative to the evaporation efficiency deviation over the past 24 hours, and calculating the first derivative of the actuator frequency adjustment amount with respect to the evaporation efficiency deviation as the sensitivity coefficient.

[0020] This invention determines the sensitivity coefficient and the basic gain offset by performing least squares regression analysis on historical operating data, making the generation process of control gain more consistent with the physical response characteristics of actual equipment and reducing the subjectivity of manually setting parameters based on experience.

[0021] Preferably, the target frequency command is obtained by multiplying the pressure deviation value by the adaptive control gain to obtain the frequency correction amount; and then accumulating the frequency correction amount to the basic operating frequency of the actuator to obtain... The target frequency command for the variable frequency drive of the fan and the target frequency command for the variable frequency drive of the spray water circulation pump.

[0022] This invention multiplies the pressure deviation value by the adaptive control gain to obtain the frequency correction amount, and then adds it to the basic operating frequency. This achieves closed-loop compensation for the frequency commands of the fan and the spray water circulation pump, ensuring that the actuator can make precise adjustments based on the current performance feedback.

[0023] Preferably, the control of the carrier gas evaporator condenser includes: performing amplitude limiting processing on the target frequency command of the fan frequency converter and the target frequency command of the spray water circulation pump frequency converter, sending the amplitude-limited target frequency command to the frequency converter via fieldbus, and synchronously adjusting the fan frequency and the spray water circulation pump frequency.

[0024] This invention performs amplitude limiting processing on the target frequency command and synchronously adjusts the frequency of the fan and the spray water circulation pump. Under the premise of ensuring the safe operation of the motor, it improves the overall heat exchange efficiency and energy efficiency ratio of the carrier gas evaporator condenser by optimizing the coordination of air volume and water film distribution.

[0025] The beneficial effects of this invention are as follows: 1. This invention changes the traditional control method's inability to perceive heat load fluctuations in real time by acquiring the instantaneous heat exchange power and evaporation efficiency ratio coefficient that change over time. This enables the operating parameters of the carrier gas evaporator condenser to closely follow the evolution of actual working conditions, reduces the deviation of condensation pressure with environmental changes, and improves the stability of the production process.

[0026] 2. By introducing adaptive control gain calculation logic, this invention realizes dynamic updating of the adjustment intensity of the actuator, and can automatically adjust the response sensitivity of the fan and spray water circulation pump according to the current heat exchange efficiency performance, reducing energy waste under low load or extreme environment and realizing optimized allocation of cooling resources.

[0027] 3. Based on the idea of ​​combining physical mechanisms and data analysis, this invention ensures that the control system has good robustness while achieving adaptive adjustment by real-time compensation of pressure deviation values ​​and limiting the frequency command. This reduces system oscillations caused by sensor errors or actuator fluctuations and extends the service life of the equipment. Attached Figure Description

[0028] Figure 1 The flowchart illustrates an adaptive optimization control method for parameters of a carrier gas evaporator condenser according to the present invention. Figure 2 This diagram illustrates a comparison of condensation pressures in a carrier gas evaporator condenser under different control methods. Figure 3 This diagram illustrates the real-time response of the actuator to the target frequency command. Detailed Implementation

[0029] 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, not all, of the embodiments of the present invention. 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.

[0030] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0031] This invention discloses an adaptive optimization control method for the parameters of a carrier gas evaporator-condenser, referring to... Figure 1 This includes steps S1 to S5: S1. Obtain a valid running dataset.

[0032] It should be noted that the sensors of the carrier gas evaporator condenser are highly susceptible to strong electromagnetic interference generated by the frequency converter during operation, which causes random noise with non-real fluctuations to be mixed into the acquired physical signals. If the original signal is not denoised, these false jump points will be amplified by the control algorithm, thereby causing unnecessary oscillations in the frequency converter drive of the fan or spray water circulation pump. This invention identifies and corrects these abnormal points by using a preset coefficient of variation threshold, thereby ensuring that every piece of data input to the control system can truly reflect the physical evolution process of the controlled object.

[0033] Specifically, this invention acquires physical signals through hardware sensors installed at key locations in the carrier gas evaporator-condenser. These physical signals include inlet carrier gas temperature, outlet carrier gas temperature, inlet carrier gas volumetric flow rate, inlet carrier gas relative humidity, and real-time spray water flow rate. The invention acquires the inlet carrier gas temperature through a thermocouple sensor installed in the inlet pipe, the outlet carrier gas temperature through a thermocouple sensor installed in the outlet pipe, the inlet carrier gas volumetric flow rate through an ultrasonic flow meter installed in the inlet pipe, the real-time spray water flow rate through an electromagnetic flow meter, and the inlet carrier gas relative humidity through a high-precision hygrometer.

[0034] Furthermore, before processing physical signals, this invention needs to pre-determine the benchmark for identifying abnormal jump points, namely, a preset coefficient of variation threshold. This threshold is derived from the statistical evaluation of the data fluctuation characteristics of the carrier gas evaporator condenser under historical stable operating conditions. This invention collects multiple sets of historical parameter sequences of the carrier gas evaporator condenser under normal operating conditions, calculates the ratio of the standard deviation of each set of sequences to its arithmetic mean, obtains a series of historical coefficients of variation, and adds a redundancy of 10% to 20% to the maximum value of these coefficients as the preset coefficient of variation threshold for determining whether the current data has undergone abnormal changes.

[0035] Furthermore, this invention converts physical signals into analog voltage signals through a data acquisition module, and then converts the analog voltage signals into discrete digital sequences using an analog-to-digital converter; this invention uses the discrete digital sequence as input and employs a sliding window algorithm to extract the current... The analysis window consists of the current time point and the thirty preceding sampling points. The ratio of the standard deviation to the arithmetic mean of the data within the window is calculated. If the ratio exceeds the preset coefficient of variation threshold, the current sampling point is determined to be a noise point, and the arithmetic mean of the ten preceding sampling points is used to replace it. Finally, the denoised valid running dataset is output.

[0036] S2, Obtain instantaneous heat exchange power.

[0037] It should be noted that the core task of a carrier gas evaporative condenser is to remove the heat carried by the carrier gas, and the rate at which heat is removed is determined by the flow rate of the carrier gas and the temperature difference between the inlet and outlet. Traditional technologies often only focus on temperature changes while ignoring fluctuations in gas volumetric flow rate over time, and also fail to consider that physical parameters such as carrier gas density will shift with ambient temperature and humidity. This invention extracts physical parameters from an effective operational dataset by time index and performs real-time property compensation, enabling accurate assessment of the heat removal rate. This invention is based on the steady-state flow energy equation of an open system in the first law of thermodynamics as the principle for constructing the expression, namely, the heat released during the isobaric cooling process of a fluid is equal to the product of its mass flow rate, isobaric specific heat capacity, and inlet / outlet temperature difference, thereby enabling real-time assessment of the energy exchange level during the condensation process.

[0038] Specifically, this invention utilizes timestamp synchronization technology to retrieve data from the storage cache of a valid running dataset. Get the value corresponding to the time. Inlet carrier gas temperature at any given time Outlet carrier gas temperature Inlet carrier gas volumetric flow rate And the relative humidity of the inlet carrier gas.

[0039] Instantaneous heat exchange power The calculation satisfies the expression: ; In the formula, express Instantaneous heat transfer power at any given moment; express The inlet carrier gas temperature at any given time; express The outlet carrier gas temperature at any given time; express The inlet carrier gas volumetric flow rate at any given time; Indicates the carrier gas density; This indicates the specific heat capacity of the carrier gas at constant pressure.

[0040] In the formula, when Inlet carrier gas temperature at any time The value increased or the outlet carrier gas temperature increased. When the value decreases, the temperature difference term obtained by the subtraction operation increases, after being compared with the inlet carrier gas volume flow rate. And the continuous multiplication calculation of physical constants makes Instantaneous heat transfer power at any moment The value increases synchronously; instantaneous heat transfer power The larger the value, the more heat the carrier gas evaporator condenser removes from the carrier gas at the current moment, reflecting a higher current condensation load demand.

[0041] It should be further noted that this invention obtains the carrier gas density by querying an aerodynamic standard property table. and specific heat capacity of carrier gas at constant pressure Specifically, this invention calculates the inlet carrier gas temperature. With outlet carrier gas temperature The arithmetic mean of the density values ​​is used. Based on this arithmetic mean and the relative humidity of the inlet carrier gas, the corresponding physical value of moist air is retrieved from the aerodynamic standard property table. The retrieved density value is then used as the carrier gas density. The retrieved specific heat capacity value is used as the specific heat capacity of the carrier gas at constant pressure. This retrieval process enables real-time correction of physical parameters based on ambient temperature and humidity, thereby improving instantaneous heat exchange power. The accuracy of the assessment.

[0042] S3. Obtain the evaporation efficiency ratio coefficient.

[0043] It should be noted that the carrier gas evaporative condenser mainly relies on the heat absorbed by the sprayed water as it evaporates on the pipe surface to remove the heat load of the carrier gas. Since changes in ambient humidity directly affect the rate of water evaporation, adjusting solely based on temperature difference will lead to low utilization of the sprayed water or insufficient heat exchange. This invention calculates the evaporation efficiency ratio coefficient and compares the actual heat removed with the theoretically maximum heat that the sprayed water can absorb, thus objectively evaluating the actual working efficiency of the system at a specific point in time. This invention is based on the ratio of actual heat absorption to the limiting latent heat of phase change as the principle for constructing the expression. That is, the actual heat removed by the system is used as the numerator, and the maximum latent heat that the sprayed water can absorb upon complete vaporization is used as the denominator. The current heat exchange efficiency is evaluated by assessing the system's utilization rate of the sprayed water's evaporation.

[0044] Specifically, the present invention obtains Instantaneous heat transfer power at any moment and real-time spray water flow Real-time spray water flow By reading the electromagnetic flowmeter The data register value corresponding to the given time can be obtained directly.

[0045] Evaporation efficiency ratio coefficient The calculation satisfies the expression: ; In the formula, express The evaporation efficiency ratio coefficient at any given time; express Instantaneous heat transfer power at any given moment; express Real-time spray water flow rate; Indicates the density of water; It represents the latent heat of vaporization of water.

[0046] In the formula, when Instantaneous heat transfer power at any moment Keep the real-time spray water flow rate constant When the denominator is increased, the multiplicative value of the denominator becomes larger, resulting in a higher evaporation efficiency ratio after division. A decrease in the value means that more water was sprayed but the expected cooling effect was not achieved; the evaporation efficiency ratio coefficient The closer the value is to 1, the closer the current heat exchange process of the carrier gas evaporator condenser is to the ideal evaporation limit, and the higher the heat exchange efficiency.

[0047] It should be further noted that, when calculating the evaporation efficiency ratio coefficient, the real-time spray water flow rate should be considered in this invention. When the value is 0, it is determined that the current spray system is in a closed state or there is no physical water flow. At this time, since the denominator is zero, division cannot be performed. This invention directly uses the evaporation efficiency ratio coefficient. The value is assigned to 0, thereby terminating the related division operation logic.

[0048] It should be further added that this invention uses a water vapor property table to obtain physical constants at the current temperature, and uses the obtained saturated water density value as the water density. The obtained latent heat of vaporization is used as the latent heat of evaporation of water. .

[0049] S4. Obtain the adaptive control gain.

[0050] It should be noted that, in order for the system to automatically adjust according to environmental changes, the controller's adjustment force must be able to sense the current heat exchange state. If the system efficiency is already high or there is a drastic change in the external heat load, a fixed adjustment parameter will lead to excessive control action causing oscillations, or insufficient control action leading to runaway condensing pressure. This invention achieves self-correction of the control model by acquiring adaptive control gain and adjusting the control weight in real time according to the deviation of the current efficiency from the reference value. This invention is based on the proportional compensation control strategy and linear mapping principle in automatic control theory as the principle basis for constructing the expression. It uses the deviation between the real-time efficiency and the reference efficiency as the driving error, uses the proportional coefficient for linear amplification and superimposes the basic offset, thereby correcting the adjustment sensitivity of the control system in real time.

[0051] Specifically, the present invention uses the arithmetic mean of all evaporation efficiency ratio coefficients obtained by collecting data from the carrier gas evaporator condenser under rated full load conditions for one hour as a preset benchmark efficiency coefficient.

[0052] Adaptive control gain The calculation satisfies the expression: ; In the formula, express Adaptive control gain at any given time; express The evaporation efficiency ratio coefficient at any given time; This represents the preset baseline performance coefficient; Indicates the sensitivity coefficient; This represents the base gain offset.

[0053] In the formula, when Evaporation efficiency ratio coefficient at time Exceeding the preset baseline performance coefficient When the efficiency deviation term calculated by subtraction is positive, it is obtained through the sensitivity coefficient. The multiplicative amplification effect causes Adaptive control gain at time The value increases; adaptive control gain An increase in the value means that the control system has a stronger ability to compensate for environmental fluctuations and can maintain a high-efficiency heat exchange state through a larger range of frequency adjustments.

[0054] It should be further noted that this invention obtains the sensitivity coefficient by performing least squares linear regression analysis on historical operating data. and base gain offset Specifically, data on the change in actuator frequency adjustment relative to evaporation efficiency deviation over the past 24 hours are collected, and the first derivative of the actuator frequency adjustment with respect to evaporation efficiency deviation is calculated as a sensitivity coefficient. The intercept of the obtained linear regression equation on the vertical axis is used as the basic gain offset.

[0055] S5. Perform feedback correction control.

[0056] It should be noted that the ultimate goal of all calculations is to issue specific speed commands to the variable frequency drive devices of the fan and spray water circulation pump, thereby stabilizing the condensing pressure. Traditional technologies cannot correlate pressure deviation with real-time heat exchange efficiency during adjustment, which can easily lead to the system operating at high power consumption at unnecessary frequency points. This invention uses adaptive control gain to dynamically compensate for pressure deviation, ensuring that the actuator can always complete the pressure stabilization task at the optimal efficiency point.

[0057] Specifically, the present invention obtains the measured value of the current condensing pressure through a pressure sensor, and defines the pressure deviation value as the measured pressure value minus a preset target value. The positive or negative value of the pressure deviation value reflects whether the condensing pressure is higher or lower than the target level.

[0058] Furthermore, the present invention will The pressure deviation value at any given time is multiplied by the adaptive control gain to obtain the frequency correction amount; subsequently, the present invention adds the frequency correction amount to the basic operating frequency of the actuator to obtain the target frequency command of the fan frequency converter and the target frequency command of the spray water circulation pump frequency converter.

[0059] Furthermore, when the pressure deviation value is greater than 0, it means that the measured pressure value is higher than the preset target value. At this time, the calculated frequency correction amount is positive, and the target frequency command of the variable frequency drive device for the fan is increased to enhance the air blowing and heat dissipation effect. In order to protect the safe operation of the motor, the present invention performs amplitude limiting processing on the target frequency command within a preset frequency range. The present invention sends the processed target frequency command to the variable frequency drive device through the fieldbus, and changes the air volume by adjusting the fan speed, and simultaneously adjusts the speed of the spray water circulation pump to change the water film thickness, thereby realizing closed-loop stable control of the condensation pressure.

[0060] For example, Figure 2 This diagram illustrates the comparison of condensing pressure in a carrier gas evaporator-condenser under different control methods. The figure shows the condensing pressure fluctuations after a significant increase in carrier gas temperature at 400 seconds, leading to a sudden surge in heat load. When using fixed-gain proportional-integral-derivative (PID) control, the control gain cannot be adjusted according to the current heat exchange efficiency, resulting in a large deviation of the condensing pressure from the target value and significant oscillations. In contrast, the adaptive optimization control of this invention, by dynamically adjusting the gain, can suppress pressure deviations, stabilizing the condensing pressure near the target value and improving the system's ability to cope with large load disturbances.

[0061] For example, Figure 3 This is a schematic diagram of the real-time response of the actuator to the target frequency command. Guided by the adaptive control gain, the two sets of actuators can perform rapid and stable frequency compensation based on small fluctuations in the condensing pressure. While ensuring that the cooling capacity meets the process requirements, it avoids the frequent and violent jumping of actuators common in traditional control, thus achieving more precise frequency control.

Claims

1. A parameter adaptive optimization control method for a carrier gas evaporator-condenser, characterized in that, include: The system acquires inlet carrier gas temperature, outlet carrier gas temperature, inlet carrier gas volumetric flow rate, inlet carrier gas relative humidity, and real-time spray water flow rate, and performs data denoising and standardization to obtain a valid operational dataset. Instantaneous heat transfer power is obtained based on the inlet carrier gas temperature, outlet carrier gas temperature, and inlet carrier gas volumetric flow rate from the effective operating dataset; the evaporation efficiency ratio is obtained based on the instantaneous heat transfer power and the real-time spray water flow rate from the effective operating dataset, satisfying the expression: , express The evaporation efficiency ratio coefficient at any given time. express Instantaneous heat transfer power at any given moment express Real-time spray water flow rate This indicates the density of water. It represents the latent heat of vaporization of water; The adaptive control gain is obtained based on the evaporation efficiency proportional coefficient and the preset benchmark efficiency coefficient, satisfying the expression: , express Adaptive control gain at any time. This represents the preset baseline performance coefficient. Represents the sensitivity coefficient. Indicates the base gain offset; The sensitivity coefficient is obtained by collecting data on the change of the actuator frequency adjustment amount relative to the evaporation efficiency deviation over the past 24 hours. The actuators are a fan and a spray water circulation pump. The first derivative of the actuator frequency adjustment amount with the evaporation efficiency deviation is calculated as the sensitivity coefficient. The pressure deviation between the measured value and the target value of the condensing pressure is obtained. Based on the pressure deviation value and the adaptive control gain, the target frequency command of the fan variable frequency drive device and the target frequency command of the spray water circulation pump variable frequency drive device are obtained to realize the control of the carrier gas evaporator condenser. The target frequency command is obtained by multiplying the pressure deviation value by the adaptive control gain to obtain the frequency correction amount; then, the frequency correction amount is accumulated and added to the actuator's base operating frequency to obtain the desired frequency. The target frequency command for the variable frequency drive of the fan and the target frequency command for the variable frequency drive of the spray water circulation pump.

2. The adaptive optimization control method for parameters of a carrier gas evaporator-condenser according to claim 1, characterized in that, The process of obtaining a valid running dataset includes: The inlet carrier gas temperature, outlet carrier gas temperature, inlet carrier gas volumetric flow rate, inlet carrier gas relative humidity, and real-time spray water flow rate are converted into analog voltage signals, and then the analog voltage signals are converted into discrete digital sequences by an analog-to-digital converter. Using the discrete digital sequences as input, the numerical difference between adjacent sampling points is calculated using a sliding window algorithm. In response to the numerical difference exceeding a preset coefficient of variation threshold, the average value of multiple preceding sampling points is used for replacement to obtain a valid running dataset.

3. The adaptive optimization control method for parameters of a carrier gas evaporator-condenser according to claim 1, characterized in that, The instantaneous heat transfer power satisfies the expression: ； In the formula, express Instantaneous heat transfer power at any given moment; express The inlet carrier gas temperature at any given time; express The outlet carrier gas temperature at any given time; express The inlet carrier gas volumetric flow rate at any given time; Indicates the carrier gas density; This indicates the specific heat capacity of the carrier gas at constant pressure.

4. The adaptive optimization control method for parameters of a carrier gas evaporator-condenser according to claim 3, characterized in that, The carrier gas density and the specific heat capacity of the carrier gas at constant pressure are obtained as follows: By querying the aerodynamic standard property table, the physical constants of the carrier gas under the current working pressure are obtained. The density constant obtained is used as the carrier gas density, and the specific heat capacity constant obtained is used as the specific heat capacity of the carrier gas at constant pressure.

5. The parameter adaptive optimization control method for a carrier gas evaporator condenser according to claim 1, characterized in that, The method for obtaining the water density and the latent heat of vaporization of water is as follows: The saturated water density and latent heat of vaporization at the working temperature are obtained using the water vapor property table. The obtained saturated water density value is taken as the water density, and the obtained latent heat of vaporization value is taken as the latent heat of vaporization of water.

6. The parameter adaptive optimization control method for a carrier gas evaporator condenser according to claim 1, characterized in that, The control of the carrier gas evaporator-condenser includes: The target frequency commands of the fan frequency converter and the spray water circulation pump frequency converter are subjected to amplitude limiting processing. The amplitude-limited target frequency commands are sent to the frequency converter via fieldbus to synchronously adjust the fan frequency and the spray water circulation pump frequency.

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