Intercooling tower shutter control system and method

Abstract

The intercooling tower shutter control system and method have the characteristics of self-adaption and high precision in the control strategy, the system can automatically adjust the control parameters in the actual operation, and the dependence on manual intervention is reduced. The complexity of operation and maintenance is reduced, and errors and faults caused by manual operation are reduced. And the problem of hysteresis or over-regulation possibly caused by a single controller is effectively avoided. By means of double-layer control, more stable control response can be provided when complex and changeable operation conditions are processed, and system instability caused by environment or load fluctuation is reduced. Through the double-layer fuzzy controller, more accurate temperature adjustment can be realized. The first-layer fuzzy controller is responsible for processing macroscopic temperature and wind speed changes, and the second-layer fuzzy controller is used for further finely adjusting the opening error and the change rate.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of indirect air cooling control of thermal power plants, and particularly relates to an indirect cooling tower shutter control system and method. BACKGROUND

[0002] With the development of the industrial and energy fields, the performance optimization of cooling systems has gradually become a key link for improving equipment efficiency and reducing energy consumption. Indirect cooling towers are widely used in the power, chemical and other industries, and their main function is to control the temperature of cooling water by adjusting the opening degree of shutters, thereby affecting the operation efficiency of the unit. However, in the actual operation process, the cooling tower is affected by various complex environmental factors and operating conditions, including environmental temperature, atmospheric wind speed and direction, unit load, etc., which makes the opening degree control of the shutter particularly complex.

[0003] Most of the existing indirect cooling tower shutter opening degree control methods use preset fixed control strategies, which are difficult to cope with dynamic changes in operating conditions, resulting in the system being unable to achieve optimal cooling effect under various environmental conditions. At the same time, the existing technology lacks a timely response mechanism for special situations (such as low-temperature anti-freezing), resulting in safety hazards when the equipment is operated in extreme environments. SUMMARY

[0004] The purpose of the present application is to provide an indirect cooling tower shutter control system and method to solve the problem of lack of timely response mechanism for special situations in the prior art, resulting in safety hazards when the equipment is operated in extreme environments.

[0005] In order to solve the above technical problems, the present application adopts the following technical solutions:

[0006] An indirect cooling tower shutter control system, comprising an indirect cooling tower, the indirect cooling tower comprising a plurality of cooling sectors and shutters, characterized in that it further comprises a data acquisition system, a controller and an execution structure.

[0007] The data acquisition system comprises a plurality of sensors, including temperature sensors, wind direction sensors, wind speed sensors, angle sensors and flow sensors. The temperature sensors include water temperature sensors and environmental temperature sensors.

[0008] At least one water temperature sensor is arranged at the water inlet and outlet of each cooling sector.

[0009] At least one flow sensor is arranged at the water inlet of each cooling sector.

[0010] A plurality of environmental temperature sensors are uniformly distributed on the indirect cooling tower.

[0011] An angle sensor, a wind direction sensor and a wind speed sensor are arranged on each of the louvers.

[0012] Each of the sensors is connected with the controller.

[0013] The execution structure comprises power devices arranged on each of the louvers, and each of the power devices is connected with the controller.

[0014] The power device is used for receiving the opening degree signal output by the controller, and adjusting the opening degree of the corresponding louver according to the opening degree signal.

[0015] The controller comprises two layers of fuzzy controllers, wherein:

[0016] The first layer of fuzzy controller receives the data detected by each sensor, and determines the preliminary opening degree of each louver according to the received data.

[0017] The second layer of fuzzy controller corrects the preliminary opening degree of each louver, obtains the corrected opening degree of the louver and transmits the opening degree signal to the corresponding power device.

[0018] The application also has the following features:

[0019] Further, the water temperature sensor adopts a triangular tube bundle temperature sensor.

[0020] The indirect cooling tower comprises 10 cooling sectors, each of the cooling sectors comprises 16 cooling triangles, and each louver corresponds to at least one cooling triangle.

[0021] Each of the cooling triangles is provided with 10 triangular tube bundle temperature sensors.

[0022] Further, the protection mode of the louver control system of the indirect cooling tower comprises a windproof protection mode, a freeze protection mode and a heat protection mode.

[0023] The windproof protection mode comprises:

[0024] Primary windproof protection: when the wind speed detected by the wind speed sensor is greater than 15 m / s, the corresponding louver is closed.

[0025] Secondary windproof protection: when the wind speed detected by the wind speed sensor is between 12 m / s and 15 m / s, the opening degree of the louver corresponding to the wind speed sensor is corrected using the following formula:

[0026]

[0027] Wherein: θ represents the corrected opening degree.

[0028] θ0 represents the modified opening degree of the louvers obtained by the second layer fuzzy controller;

[0029] v represents the wind speed detected by the wind speed sensor;

[0030] The anti-freezing protection mode includes:

[0031] Primary anti-freezing: 40% of the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than 27℃, reduce the increasing rate of the louvers opening degree, and make the increasing rate ≤0.083% / s;

[0032] Secondary anti-freezing: 20% of the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than 25℃, make the maximum opening degree of the corresponding louvers no more than 40%;

[0033] Tertiary anti-freezing: 20% of the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than 20℃, make the corresponding louvers completely closed;

[0034] The anti-heat protection mode first sets the threshold of the triangular tube bundle temperature sensors, including:

[0035] Primary anti-heat: More than 20% of the sensors in a single cooling sector have a temperature exceeding the threshold by 3℃, increase the opening degree of the corresponding louvers;

[0036] Secondary anti-heat: More than 10% of the sensors in a single cooling sector have a temperature exceeding the threshold by 5℃, make the corresponding louvers completely open.

[0037] Further, when all the triangular tube bundle temperature sensors in a single cooling sector detect a temperature higher than 30℃ and delay for 300s, the anti-freezing protection mode of the corresponding louvers is removed;

[0038] When all the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than the threshold and delay for 180s, the anti-heat protection mode of the corresponding louvers is removed.

[0039] A method for controlling the louvers of an indirect cooling tower, which is based on the above-mentioned indirect cooling tower louver control system, including the following steps:

[0040] Step 1, select a cooling sector, detect the outlet water temperature and wind speed of the cooling sector, and calculate the actual outlet water temperature according to the detected outlet water temperature;

[0041] Step 2, the first layer fuzzy controller receives the actual outlet water temperature and wind speed of the cooling sector, and outputs the output variable set of the actual outlet water temperature and wind speed as the output set;

[0042] Step 3, use the weighted average method to clarify the output set of the first layer fuzzy controller, and further obtain the preliminary opening degree of the louvers corresponding to the cooling sector;

[0043] Step 4, the second layer fuzzy controller calculates the correction amount of the louver according to the initial opening degree of the louver using the weighted average method, and further obtains the opening degree value of the corrected louver;

[0044] Step 5, it is judged whether the current satisfies the condition of one or multiple protection modes;

[0045] If the condition of any protection mode is not satisfied or only the condition of one protection mode is satisfied, step 6 is entered;

[0046] If the conditions of multiple protection modes are satisfied at the same time, the protection mode with the highest weight is selected according to the corresponding weight, and step 6 is entered;

[0047] Step 6, it is judged whether the opening degree range of the selected protection mode conflicts with the opening degree value of the corrected louver;

[0048] If there is a conflict, the louver is adjusted to the maximum or minimum opening degree value allowed in the selected protection mode, and step 7 is entered;

[0049] If there is no conflict, the louver is adjusted to the opening degree value of the corrected louver, and step 7 is entered;

[0050] Step 7, an unprocessed cooling sector is selected, and steps 1-7 are repeated until each cooling sector is traversed.

[0051] Further, in step 1, the actual outlet water temperature is calculated using the following formula:

[0052]

[0053] Wherein, T out represents the actual outlet water temperature;

[0054] T env represents the ambient temperature detected by the ambient temperature sensor;

[0055] T in represents the water temperature detected by the water temperature sensor at the inlet of the cooling sector;

[0056] NTU represents the heat exchange efficiency of the cooling sector;

[0057] Wherein, the heat exchange efficiency of the cooling sector is calculated using the following formula:

[0058]

[0059] Wherein, A represents the heat transfer area of the cooling sector;

[0060] K represents the heat transfer coefficient;

[0061] The liquid flow rate detected by the flow sensor representing the cooling sector.

[0062] Further, the output set of the first layer fuzzy controller is clarified using weighted average method in step 3, as follows:

[0063]

[0064] Where k x (t) represents the clarified output set;

[0065] i and j represent the circulating variables of actual outlet water temperature and air speed respectively;

[0066] μi represents the i-th membership value of the actual outlet water temperature in the first layer fuzzy controller;

[0067] μj represents the j-th membership value of the air speed in the first layer fuzzy controller;

[0068] The preliminary opening O of the louvers is calculated using the following formula:

[0069]

[0070] Where, μ represents the membership degree of the output set O i ;

[0071] μ represents the center value corresponding to the output set O i , which is usually taken as the centroid of the fuzzy set.

[0072] Further, in step 4, the louvers correction amount is calculated using weighted average method as follows:

[0073]

[0074] Where, μ represents the membership degree of the fuzzy set ΔO i ;

[0075] μ represents the center value of the fuzzy set;

[0076] The opening value O of the corrected louvers is obtained as follows: new

[0077] O mew = O current + ΔO

[0078] Where O current is the current louver opening. ​

[0079] Further, the weight of each protection mode in step 5 is shown as follows:

[0080]

[0081] Compared with the prior art, the present application has the following technical effects:

[0082] The intermediate cooling tower shutter control system and method of the present application has the characteristics of self-adaptation and high precision in control strategy. The system can automatically adjust the control parameters in actual operation, reducing the dependence on manual intervention. This not only reduces the complexity of operation and maintenance, but also reduces errors and failures caused by human operation. It effectively avoids the problems of hysteresis or over-regulation that may occur in a single controller. The double-layer control can provide more stable control response when dealing with complex and variable operating conditions, reducing the system instability caused by environmental or load fluctuations.

[0083] By using a double-layer fuzzy controller, the present application can achieve more accurate temperature regulation. The first layer fuzzy controller is responsible for handling macro temperature and wind speed changes, while the second layer fuzzy controller further adjusts the opening error and rate of change. This layered control strategy greatly improves the control accuracy of the system, ensuring more stable cooling effect and avoiding safety hazards when the equipment is running in extreme environments, and is suitable for large-scale use and promotion in industry. BRIEF DESCRIPTION OF DRAWINGS

[0084] Figure 1 The figure is a control block diagram of the fuzzy reasoning system in the intermediate cooling tower shutter opening control of the present application.

[0085] Figure 2 The figure is a flowchart of the intermediate cooling tower shutter opening control of the present application.

[0086] Figure 3 The figure is a schematic diagram of the sector data acquisition and data transmission device in the present application.

[0087] Figure 4 The figure is a flowchart of the system operation protection control adjustment in the present application. DETAILED DESCRIPTION

[0088] It should be noted that all components in the present application, such as controllers, use known components in the prior art unless otherwise specified.

[0089] The following gives specific embodiments of the present application. It should be noted that the present application is not limited to the following specific embodiments, and any equivalent variations made on the basis of the technical solutions of the present application fall within the scope of protection of the present application.

[0090] A kind of intercooling tower louvre control system, including intercooling tower, intercooling tower includes multiple cooling sectors and louvre;It further includes data acquisition system, controller and execution structure;

[0091] Data acquisition system includes multiple temperature sensors, wind direction sensor, wind speed sensor and angle sensor and flow sensor;Wherein, temperature sensor includes water temperature sensor, ambient temperature sensor, at least one water temperature sensor is arranged at the water inlet and water outlet of each cooling sector;At least one flow sensor is arranged at the water inlet of each cooling sector;Multiple ambient temperature sensors are evenly distributed on intercooling tower;Each louvre is provided with an angle sensor, wind direction sensor and wind speed sensor;

[0092] Each sensor of data acquisition system is connected with controller respectively;

[0093] Execution structure includes power device arranged on each louvre, and each power device is connected with controller respectively;Power device is used to adjust the opening of corresponding louvre according to the signal output by controller;

[0094] Controller includes two layers of fuzzy controllers;Controller is used to:

[0095] Set the initial target opening of each louvre;

[0096] Receive the data detected by each sensor;

[0097] First layer fuzzy controller determines the preliminary opening of each louvre according to the received data;Determine opening error and error variation rate according to the corresponding initial target opening of each louvre;

[0098] Second layer fuzzy controller determines the adjusted louvre target opening according to opening error and error variation rate;

[0099] The adjusted target louvre opening is transmitted to corresponding power device.

[0100] Optionally, the power device of execution mechanism adopts servo motor and worm gear transmission.

[0101] Redundant fiber ring network is used for communication between components.

[0102] Optionally, the controller also displays the basic information of current unit, including the identification, number, name of unit and the current running state (such as running, shutdown, maintenance, etc.) of unit.

[0103] As a preferred scheme, the water temperature sensor adopts triangular tube bundle temperature sensor;

[0104] The indirect cooling tower comprises 10 cooling sectors; each cooling sector comprises 16 cooling triangles, and each two cooling triangles correspond to one louvre;

[0105] Each cooling triangle is provided with 10 triangle tube bundle temperature sensors.

[0106] One unit comprises ten sectors, each sector has 16 cooling triangles, two cooling triangles correspond to one louvre, and each cooling triangle is provided with ten triangle tube bundle temperature sensors. The data acquisition and data transmission module transmits sensor data to the control system through a wired network, ensuring the real-time and accuracy of the data.

[0107] As a preferred solution, a wind protection controller is further included; the wind protection controller is connected with the controller, each wind speed sensor and each power device respectively;

[0108] The wind protection controller comprises the following wind protection modes:

[0109] When the wind speed is greater than 15 m / s, the wind protection controller controls each power device to close the corresponding louvre.

[0110] The system is equipped with a high wind speed protection mode, which can automatically adjust the opening degree of the louvre in strong wind weather conditions to avoid damage to the equipment due to overload.

[0111] As a preferred solution, a temperature protection controller is further included; the temperature protection controller is connected with the controller, each triangle tube bundle temperature sensor and each power device respectively.

[0112] The temperature protection controller comprises the following anti-freezing protection mode and anti-heat protection mode:

[0113] First-level anti-freezing: in a single cooling sector, if the temperature detected by 40% of the triangle tube bundle temperature sensors is lower than 27℃, the temperature protection controller controls the corresponding power device to limit the opening degree of the corresponding louvre to ≤5% / min;

[0114] Second-level anti-freezing: in a single cooling sector, if the temperature detected by 20% of the triangle tube bundle temperature sensors is lower than 25℃, the temperature protection controller controls the corresponding power device to limit the maximum opening degree of the corresponding louvre to no more than 40%;

[0115] Third-level anti-freezing: in a single cooling sector, if the temperature detected by 20% of the triangle tube bundle temperature sensors is lower than 20℃, the temperature protection controller controls the corresponding power device to completely close the corresponding louvre;

[0116] First-level anti-heat: in a single cooling sector, if the temperature detected by 20% of the triangle tube bundle temperature sensors is higher than the set threshold value of 3℃, the opening angle of the louvre is relaxed;

[0117] Secondary heat protection: In a single cooling sector, if 10% of the triangular tube bundle temperature sensors detect a temperature 5°C higher than the set threshold, the opening angle of the louvers is expanded;

[0118] Wherein, when all the triangular tube bundle temperature sensors in a single cooling sector detect a temperature higher than 30°C for 300 seconds, the corresponding anti-freezing protection mode is lifted;

[0119] When all the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than the set threshold for 180 seconds, the corresponding heat protection mode is lifted.

[0120] Secondly, according to seasonal or temperature changes, the system intelligently identifies and automatically switches between anti-freezing and heat protection modes to meet temperature control requirements in different environments. When the temperature changes, the system dynamically adjusts the louver opening based on environmental temperature and load changes through a flexible adjustment mechanism, optimizes heat dissipation, and achieves reasonable energy consumption distribution.

[0121] The threshold limit mechanism provides safety protection for the entire control strategy, ensuring that temperature or other indicators are within limits by monitoring and limiting key parameters in real time.

[0122] In addition, in the anti-freezing mode, the system pays special attention to the anti-freezing protection of the triangular tube bundle, avoiding ice formation on the tube bundle under low temperature conditions through precise operation control. When the triangular tube bundle overheats, the system quickly adjusts the parameters to prevent high temperatures from damaging the equipment.

[0123] The embodiment also provides a fuzzy control-based louver opening control method for an indirect cooling tower. First, the actual louver opening detected by the current angle sensor, the target opening of the louver in the previous cycle, and multiple parameters affecting heat dissipation, such as inlet water temperature, outlet water temperature, environmental temperature, atmospheric wind speed and direction, power generation, and circulating water volume, are obtained in real time.

[0124] Then, fuzzy control rules are designed based on these data. The input variables include actual opening error and error change rate, and the output variable is the adjustment amplitude of the louver. These rules comprehensively consider various influencing factors to ensure that the system can obtain reasonable control output under various working conditions.

[0125] Subsequently, through a fuzzy inference system, based on the input variables and the preset fuzzy control rules, the initial target opening of the louver in the next cycle is calculated, with a value range of 0% to 100%. The controller automatically adjusts the opening of the louver according to the calculated target opening, and uses the angle sensor to monitor the actual opening of the louver in real time. If the current opening is not within the preset range, the system will continue to adjust until the opening reaches the target value.

[0126] During system operation, if the anti-freeze protection feature is triggered, the system will prioritize anti-freeze measures and suspend the optimization process for the opening degree. After the anti-freeze protection is released, the system will continue to perform optimization operations to ensure the safe operation of the equipment in the low-temperature environment. Based on the initial error value, the system performs temperature offsetting and automatic optimization, using the superimposed calculated water temperature value as the final target value for water temperature control. Through automatic optimization, the outlet water temperature of the sector is effectively reduced, further reducing the unit's operating back pressure, thereby improving the overall efficiency of the system.

[0127] The entire system uses the target outlet water temperature and actual wind speed as the main inputs and is divided into two control layers. First, the first-layer fuzzy controller calculates the target louver opening based on changes in the target outlet water temperature and actual wind speed. After fuzzification and fuzzy inference, a preliminary louver opening adjustment value is generated. Next, the second-layer controller performs a finer adjustment based on the difference between the actual louver opening and the target opening. Through further fuzzification, inference, and defuzzification steps, the precise louver opening is finally determined. The entire system continuously monitors and adjusts the louver opening through real-time feedback, ensuring the indirect cooling tower operates stably and efficiently under various environmental conditions.

[0128] A louver control system for an indirect cooling tower includes an indirect cooling tower, which includes multiple cooling sectors and louvers, and also includes a data acquisition system, a controller, and an execution structure.

[0129] The data acquisition system includes multiple sensors; specifically, these sensors include temperature sensors, wind direction sensors, wind speed sensors, angle sensors, and flow sensors; the temperature sensors include water temperature sensors and ambient temperature sensors.

[0130] At least one water temperature sensor is installed at the inlet and outlet of each cooling sector;

[0131] Each cooling sector inlet is equipped with at least one flow sensor;

[0132] Multiple ambient temperature sensors are evenly distributed on the indirect cooling tower;

[0133] Each louver is equipped with an angle sensor, a wind direction sensor, and a wind speed sensor;

[0134] Each sensor is connected to the controller;

[0135] The actuation structure includes a power unit installed on each louver, and each power unit is connected to the controller;

[0136] The power unit is used to receive the opening signal output by the controller and adjust the opening degree of the corresponding louver according to the opening signal;

[0137] The controller comprises two layers of fuzzy controllers, wherein:

[0138] The first layer of fuzzy controller receives data detected by each sensor, and determines a preliminary opening degree of each louver according to the received data;

[0139] The second layer of fuzzy controller corrects the preliminary opening degree of each louver, obtains a corrected opening degree of the louver, and transmits an opening degree signal to a corresponding power device.

[0140] Optionally, the power device of the actuator adopts a servo motor and a worm gear transmission.

[0141] Redundant fiber ring networks are used for communication between components.

[0142] Optionally, the controller also displays basic information of the current unit, including the identification, number, name of the unit, and the current running state (such as running, shutdown, maintenance, etc.) of the unit.

[0143] The temperature distribution statistics part calculates the abnormal proportion index by statistically analyzing all the triangular tube bundle temperature sensor data, to identify the overall thermal state of the cooling sector. The abnormal sensor proportion calculation formula is as follows:

[0144]

[0145] Wherein, N abnormal is the number of sensors detected with temperature lower or higher than the set threshold, N total is the total number of sensors installed in the sector. The weighted temperature average model further enhances the system's perception of temperature changes in critical positions:

[0146]

[0147] Wherein, W i is the weight coefficient of the i-th sensor, which is set according to its criticality in the cooling path and historical stability, T i is its current reading, which needs to be processed by sliding filter to remove noise.

[0148] Adaptive dynamic threshold adjustment is based on system identification and adaptive control theory, and the following dynamic temperature control threshold model is constructed:

[0149] T threshold (t)=T base +α·σ(t)+β·ΔT trend (t)

[0150] Wherein, T base is the device design reference temperature, σ(t) is the current temperature standard deviation, reflecting the dispersion degree of sensor reading distribution, ΔT trend(t) is the temperature trend increment, representing the rate of change of the system heat, and a, b are dynamic adjustment coefficients.

[0151] The temperature trend is calculated by the following formula:

[0152]

[0153] The trend variable is used to predict the temperature trend, realize early control and risk prediction.

[0154] As a preferred solution, the water temperature sensor adopts a triangular tube bundle temperature sensor;

[0155] The indirect cooling tower includes 10 cooling sectors; each cooling sector includes 16 cooling triangles, and each louver corresponds to at least one cooling triangle;

[0156] Each cooling triangle is provided with 10 triangular tube bundle temperature sensors.

[0157] As a preferred solution, the indirect cooling tower louver control system includes a wind protection mode, a freeze protection mode, and a heat protection mode:

[0158] The wind protection mode includes:

[0159] First-level wind protection: when the wind speed sensor detects a wind speed greater than 15 m / s, the corresponding louver is closed;

[0160] Second-level wind protection: when the wind speed sensor detects a wind speed between 12 m / s and 15 m / s, the following formula is used to correct the opening of the louver corresponding to the wind speed sensor:

[0161]

[0162] Where: θ represents the corrected opening;

[0163] θ0 represents the opening of the louver corrected by the second layer fuzzy controller;

[0164] v represents the wind speed detected by the wind speed sensor;

[0165] The freeze protection mode includes:

[0166] First-level freeze protection: when 40% of the triangular tube bundle temperature sensors in a single cooling sector detect a temperature below 27℃, the growth rate of the louver opening is reduced to ≤0.083% / s;

[0167] Second-level freeze protection: in a single cooling sector, when 20% of the triangular tube bundle temperature sensors detect a temperature below 25℃, the maximum opening of the corresponding louver is not greater than 40%;

[0168] Third-level freeze protection: In a single cooling sector, if 20% of the triangular tube bundle temperature sensors detect a temperature below 20°C, the corresponding louvers are fully closed.

[0169] The heat protection mode first sets the threshold for the triangular tube bundle temperature sensors, including:

[0170] First-level heat protection: In a single cooling sector, if more than 20% of the sensors have a temperature 3°C above the threshold, the corresponding louver opening is increased.

[0171] Second-level heat protection: In a single cooling sector, if more than 10% of the sensors have a temperature 5°C above the threshold, the corresponding louver is fully opened.

[0172] As a preferred solution, when all triangular tube bundle temperature sensors in a single cooling sector detect a temperature above 30°C and delay for 300 seconds, the corresponding freeze protection mode is removed;

[0173] When all triangular tube bundle temperature sensors in a single cooling sector detect a temperature below the threshold and delay for 180 seconds, the corresponding heat protection mode is removed.

[0174] Secondly, according to the season or temperature change, the system intelligently identifies and automatically switches between freeze protection and heat protection operation modes to meet the temperature control requirements in different environments. When the temperature changes, the system dynamically adjusts the louver opening according to the environmental temperature and load changes through a flexible adjustment mechanism, optimizes the heat dissipation effect and realizes reasonable distribution of energy consumption.

[0175] The threshold limit mechanism provides safety protection for the entire control strategy, ensuring that temperature or other indicators are out of limits and timely protection measures are taken.

[0176] In addition, in the freeze protection mode, the system pays special attention to the freeze protection of the triangular tube bundle, avoiding ice formation on the tube bundle under low temperature conditions through precise operation control. When the triangular tube bundle overheats, the system quickly adjusts the parameters to prevent high temperature from damaging the equipment.

[0177] The embodiment also provides a fuzzy control-based louver opening control method for an indirect cooling tower. First, the actual louver opening detected by the current angle sensor, the target opening of the louver in the last cycle, and multiple parameters affecting heat dissipation, such as inlet water temperature, outlet water temperature, environmental temperature, atmospheric wind speed and direction, power generation, and circulating water volume, are obtained in real time.

[0178] Then, fuzzy control rules are designed based on these data. The input variables include actual opening error and error change rate, and the output variable is the adjustment amplitude of the louver. These rules comprehensively consider various influencing factors to ensure that the system can obtain reasonable control output under various working conditions.

[0179] Subsequently, through the fuzzy inference system, the initial target opening of the louvers in the next period is calculated based on the input variables and the preset fuzzy control rules, with a value range of 0% to 100%. The controller automatically adjusts the opening of the louvers according to the calculated target opening, and uses the angle sensor to monitor the actual opening of the louvers in real time. If the current opening is not within the preset range, the system will continue to adjust until the opening reaches the target value.

[0180] During system operation, if the anti-freezing protection feature is triggered, the system will prioritize anti-freezing measures and suspend the opening optimization process. After the anti-freezing protection is lifted, the system will continue to perform optimization operations to ensure the safe operation of the equipment in low-temperature anti-freezing environments. Based on the preliminary error value, the system performs temperature biasing and automatic optimization, and adds the calculated water temperature value as the final target value for water temperature control. Through automatic optimization, the sector outlet water temperature is effectively reduced, further reducing the operating back pressure of the unit, thereby improving the overall efficiency of the system.

[0181] A method for controlling the louvers of an intercooling tower, based on an intercooling tower louver control system, comprising the following steps:

[0182] Step 1: Select a cooling sector, detect the outlet water temperature and wind speed of the cooling sector, and calculate the actual outlet water temperature based on the detected outlet water temperature;

[0183] The starting point of the process is the collection of the actual outlet water temperature, which is the basic data of the entire control system. The system obtains the outlet water temperature through sensors and judges the cooling effect according to the preset target temperature. Next, the system monitors the wind speed and determines whether the actual wind speed has changed. If the wind speed has changed significantly, it means that the external environmental conditions have changed, and the system will enter the parameter update stage at this time. This step is very important to ensure that the control system can update control parameters in real time in a dynamic environment and maintain the ability to adapt to environmental changes. After updating the parameters, the main fuzzy controller starts working. The main fuzzy controller calculates and adjusts the initial opening of the louvers based on the new environmental parameters and the preset control rules. This initial opening adjustment is the initial response of the system to changes in external conditions. Subsequently, the system updates the initial opening to meet the current operating conditions. If the system detects that the equipment needs protection, especially in extreme environments such as low-temperature icing prevention, the system may set the opening of the louvers to 0 to prevent cold air from entering and protect the safety of the equipment.

[0184] As Figure 1As shown, the figure shows a schematic diagram of a sector data acquisition and data transmission device, including the design of the data acquisition and data transmission device by installing various sensors to monitor the running state of the intercooling tower in real time. Including angle sensor for measuring the actual opening of the louvers, temperature sensor for measuring the inlet water temperature, sector outlet water temperature and ambient temperature, atmospheric wind speed and direction sensor for monitoring weather conditions, flow sensor for measuring circulating water volume.

[0185] In step 1, the actual outlet water temperature is calculated using the following formula:

[0186]

[0187] Where T out represents the actual outlet water temperature;

[0188] T env represents the ambient temperature detected by the ambient temperature sensor;

[0189] T in represents the water temperature detected by the water temperature sensor at the inlet of the cooling sector;

[0190] NTU represents the heat exchange efficiency of the cooling sector;

[0191] Where the heat exchange efficiency of the cooling sector is calculated using the following formula:

[0192]

[0193] Where A represents the heat transfer area of the cooling sector;

[0194] K represents the heat transfer coefficient;

[0195] represents the liquid flow rate detected by the flow sensor of the cooling sector.

[0196] Step 2, the first layer fuzzy controller receives the actual outlet water temperature and wind speed of the cooling sector, and outputs the output variable set of the actual outlet water temperature and wind speed as the output set;

[0197] Step 3, the output set of the first layer fuzzy controller is clarified using the weighted average method, and the preliminary opening of the louvers corresponding to the cooling sector is obtained;

[0198] Step 4, the second layer fuzzy controller calculates the correction amount of the louvers according to the preliminary opening of the louvers using the weighted average method, and obtains the opening value of the corrected louvers;

[0199] Step 5, determine whether the current conditions meet one or more protection modes;

[0200] If any one of the protection modes is not met or only one protection mode is met, go to step 5;

[0201] If the conditions of multiple protection modes are met at the same time, select the protection mode with the highest weight according to the corresponding weight, and go to step 6;

[0202] Step 6, judge whether the selected protection mode corresponding to the louver opening range conflicts with the corrected louver opening value;

[0203] If there is a conflict, adjust the louver to the maximum or minimum opening value allowed in the selected protection mode, and go to step 7;

[0204] If there is no conflict, adjust the louver to the corrected louver opening value, and go to step 7;

[0205] Step 8, select an unprocessed cooling sector, repeat steps 1-7 until each cooling sector is traversed.

[0206] The target louver opening preliminary value can also be determined directly by the expert experience library through fuzzy reasoning. The expert experience library is an intelligent control method based on historical data and expert knowledge, which can dynamically adjust the opening and angle of the louver to cope with complex and changing external environment. First, the opening of the louver will be automatically adjusted based on the outlet water temperature, external air temperature, wind speed and the best operation strategy in the expert experience library. The expert experience library stores a large amount of data about the relationship between outlet water temperature, external air temperature, wind speed and louver opening. The system will automatically adjust the angle of the louver according to real-time data and historical records in the experience library to ensure stable operation of the system.

[0207] Specifically, the first layer fuzzy controller is the core and basic part of the entire control system, mainly responsible for the preliminary processing and control of the basic input of the system, to ensure that the system can preliminarily adjust the louver opening according to the current operating conditions. It calculates the data according to the temperature control model, performs fuzzy processing on the input parameters, and determines the preliminary opening of the louver through fuzzy reasoning. The input variables include the target outlet water temperature T out , the actual wind speed V wind .

[0208] The target outlet water temperature is the expected value of the control system error, indicating the water temperature level that the cooling tower should reach; the actual wind speed directly affects the heat transfer efficiency and air flow of the cooling tower; the inlet water temperature is the water temperature entering the cooling tower. The main purpose of the first layer fuzzy control is to ensure that the system can quickly and effectively respond when facing changing target outlet water temperature and actual wind speed through preliminary adjustment, providing a basic adjustment for the subsequent more detailed control layer, achieving preliminary stable control to quickly respond to environmental changes.

[0209] The fuzzy sets of the input variables (target outlet water temperature, actual wind speed) and output variable (louver opening Y) of the system are defined, usually using five sets to describe the different states of the variables, namely negative big (NB), negative small (NS), zero (ZE), positive small (PS), and positive big (PB). The following is the fuzzy control rule table of the first layer fuzzy controller:

[0210] Table 1 Fuzzy control rule table of the first layer fuzzy controller

[0211]

[0212]

[0213] Specifically, when the output set of the first layer fuzzy controller is clarified using the weighted average method in step 3, the following formula is used:

[0214]

[0215] wherein k x (t) represents the clarified output set;

[0216] i and j represent the cyclic variables of the actual outlet water temperature and wind speed, respectively;

[0217] represents the i-th membership value opposite to the actual outlet water temperature in the first layer fuzzy controller;

[0218] represents the j-th membership value opposite to the wind speed in the first layer fuzzy controller.

[0219] Further, the input variables of the second layer fuzzy controller include the opening error E, i.e. the difference between the louver opening of the first layer output and the actual opening, and the error change rate ΔE, i.e. the rate or trend of louver opening adjustment, and the output variable is the louver output adjustment amount ΔO. When the opening error E is negative big (NB) and the error change rate ΔE is negative big (NB), ΔO is zero (ZE). This means that when the current opening is significantly low and the error change rate indicates that the trend is decreasing, the system does not need to be adjusted and the status quo can be maintained.

[0220] When the opening error E is positive big (PB) and the error change rate ΔE is positive big (PB), ΔO is positive small (PS). This means that the current opening is too high and the change rate indicates that the trend is increasing, and the system should gradually reduce the opening.

[0221] Specifically, the weights of each protection mode in step 5 are as follows in the priority weight matrix Priority_Matrix:

[0222]

[0223] According to the weight of each protection mode, the selected matrix can be determined, and a more detailed method is given in this embodiment:

[0224] Active_Modes={mode i |Condition(mode i )=TRUE}

[0225] Wherein, mode i represents all the protection modes that can be recognized by the system, such as “first-level anti-freezing” and “third-level anti-heat”, and Condition(mode i )=TRUE indicates that the mode is currently triggered;

[0226] Select the protection mode with the highest priority:

[0227] Selected_Mode=argmax(Priority_Matrix[mode]),mode∈Active_Modes

[0228] Wherein, Priority_Matrix[mode] represents the priority value corresponding to each mode, and argmax represents selecting the mode with the maximum priority.

Claims

1. An indirect air cooled tower louvre control system comprising an indirect air cooled tower, said indirect air cooled tower comprising a plurality of cooling sectors and louvres, characterised in that, Also include data acquisition system, controller and execution structure; The data acquisition system includes a plurality of sensors; the sensor specifically includes: temperature sensor, wind direction sensor, wind speed sensor and angle sensor and flow sensor; The temperature sensor includes water temperature sensor and ambient temperature sensor; At least one water temperature sensor is arranged at the water inlet and outlet of each cooling sector; At least one flow sensor is arranged at the water inlet of each cooling sector; The indirect cooling tower is uniformly distributed with a plurality of ambient temperature sensors; An angle sensor, a wind direction sensor and a wind speed sensor are arranged on each louver; Each of the sensors is connected with the controller; The execution structure includes a power device arranged on each louver, and each power device is connected with the controller; The power device is used for receiving the opening degree signal output by the controller, and adjusting the opening degree of the corresponding louver according to the opening degree signal; The controller includes two layers of fuzzy controllers, wherein: The first layer of fuzzy controller receives the data detected by each sensor, and determines the preliminary opening degree of each louver according to the received data; The second layer of fuzzy controller corrects the preliminary opening degree of each louver, obtains the corrected opening degree of the louver and transmits the opening degree signal to the corresponding power device.

2. The indirect air cooling tower louver control system of claim 1, wherein, The water temperature sensor adopts a triangular tube bundle temperature sensor; The indirect cooling tower includes 10 cooling sectors; Each of the cooling sectors includes 16 cooling triangles, and each louver corresponds to at least one cooling triangle; Ten triangular tube bundle temperature sensors are arranged on each cooling triangle.

3. The indirect air cooled tower shutter control system of claim 2, wherein, The protection mode of the louver control system of the indirect cooling tower includes windproof protection mode, anti-freezing protection mode and heat protection mode: The windproof protection mode includes: First level windproof protection: when the wind speed detected by the wind speed sensor is greater than 15 m / s, the corresponding louver is closed; Second level windproof protection: when the wind speed detected by the wind speed sensor is between 12 m / s and 15 m / s, the opening degree of the louver corresponding to the wind speed sensor is corrected using the following formula: Wherein: θ represents the corrected opening degree; θ0 represents the corrected opening degree of the louver obtained by the second layer of fuzzy controller; V represents the wind speed detected by the wind speed sensor; The anti-freezing protection mode includes: First level anti-freezing: when 40% of the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than 27℃, the growth rate of the louver opening degree is reduced, and the growth rate is ≤0.083% / s; Second level anti-freezing: when 20% of the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than 25℃, the maximum opening degree of the corresponding louver is not greater than 40%; Third level anti-freezing: when 20% of the triangular tube bundle temperature sensors in a single cooling sector detect a temperature lower than 20℃, the corresponding louver is completely closed; The heat protection mode first sets the threshold value of the triangular tube bundle temperature sensor, including: First level heat protection: when 20% or more sensors in a single cooling sector exceed the threshold value by 3℃, the opening degree of the corresponding louver is increased; Secondary heat protection: If more than 10% of the sensors in a single cooling sector exceed the threshold of 5℃, the corresponding louvers are fully opened.

4. The indirect air cooled tower shutter control system of claim 3, wherein, When all the temperature sensors in a single cooling sector detect a temperature higher than 30℃ for 300s, the corresponding anti-freezing protection mode is released. When all the temperature sensors in a single cooling sector detect a temperature lower than the threshold for 180s, the corresponding anti-heat protection mode is released.

5. A method of controlling the louvers of an indirect air cooled tower, based on the indirect air cooled tower louver control system of claim 4, characterized in that, The method comprises the following steps: Step 1: Select a cooling sector, detect the outlet water temperature and air speed of the cooling sector, and calculate the actual outlet water temperature according to the detected outlet water temperature; Step 2: The first layer fuzzy controller receives the actual outlet water temperature and air speed of the cooling sector, and outputs a set of output variables of the actual outlet water temperature and air speed as an output set; Step 3: The output set of the first layer fuzzy controller is clarified using the weighted average method, and the preliminary opening degree of the corresponding louvers of the cooling sector is obtained; Step 4: The second layer fuzzy controller calculates the correction amount of the louvers using the weighted average method according to the preliminary opening degree of the louvers, and obtains the opening degree value of the corrected louvers; Step 5: Determine whether the conditions of one or multiple protection modes are met at the same time; If the conditions of any one protection mode are not met or only the conditions of one protection mode are met, go to Step 6; If the conditions of multiple protection modes are met at the same time, select the protection mode with the highest weight according to the corresponding weight, and go to Step 6; Step 6: Determine whether the opening degree range of the selected protection mode conflicts with the opening degree value of the corrected louvers; If there is a conflict, adjust the louvers to the maximum or minimum opening degree value allowed under the selected protection mode, and go to Step 7; If there is no conflict, adjust the louvers to the opening degree value of the corrected louvers, and go to Step 7; Step 7: Select an unprocessed cooling sector, repeat Steps 1-7 until each cooling sector is processed.

6. The indirect air cooled tower shutter control method of claim 5, wherein, In Step 1, the actual outlet water temperature is calculated using the following formula: where T out represents the actual outlet water temperature; T env represents an ambient temperature detected by an ambient temperature sensor; T in Twaterin represents the water temperature detected by the water temperature sensor at the inlet of the cooling sector; NTU represents the heat exchange efficiency of the cooling sector; Wherein, the heat exchange efficiency of the cooling sector is calculated using the following formula: Wherein, A represents the heat transfer area of the cooling sector; K represents the heat transfer coefficient; represents the liquid flow detected by the flow sensor of the cooling sector.

7. The indirect air cooled tower shutter control method of claim 6 wherein, In Step 3, when the output set of the first layer fuzzy controller is clarified using the weighted average method, the following formula is used: where k x (t) denotes the set of outputs after clarification; i and j represent the loop variables of the actual outlet water temperature and air speed, respectively; i represents the i-th membership value of the actual outlet water temperature in the first layer fuzzy controller; j represents the jth membership value of the wind speed opposite to the first layer fuzzy controller; The preliminary opening degree O of the louvers is calculated using the following formula: wherein, represents the membership of the output set O i . representing the center value of the corresponding output set O i of the fuzzy set.

8. The indirect air cooled tower shutter control method of claim 7, wherein, In Step 4, the correction amount of the louvers is calculated using the weighted average method as follows: wherein, represents the membership of the fuzzy set Δ0 i . representing the center value of the fuzzy set; acquiring the corrected opening value O of the shutter new the following equation: O new =O current +ΔO where O current is the current window opening.

9. The indirect air cooled tower shutter control method of claim 8 wherein, In Step 5, the weights of each protection mode are as follows:

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