Low-temperature accurate control indirect cooling tower system and control method

Abstract

The invention provides a low-temperature accurate control indirect cooling tower system and a control method. The low-temperature accurate control indirect cooling tower system comprises an air cooling tower, and sector cooling areas are integrated in the air cooling tower; a cooling assembly is arranged in the sector cooling area, the cooling assembly comprises a shutter, heat exchange tube sets are arranged at the two ends of the shutter respectively, and the two heat exchange tube sets and the shutter are arranged in a triangular shape; water inlets of the heat exchange tube sets located at the two ends of the shutter are connected in series through a first conveying pipe, water outlets of the heat exchange tube sets located at the two ends of the shutter are connected in series through a second conveying pipe, and a circulating water system is connected between the second conveying pipe and the first conveying pipe. A first pressure transmitter is arranged close to the triangle; a second pressure transmitter is arranged in the sector cooling area; and the second pressure transmitter, the first pressure transmitter and the regulator of the shutter are respectively in communication connection with the regulation terminal. According to the system, partition regulation and control are combined with accurate temperature control, the running state of each sector can be dynamically adjusted according to the load of the turboset, invalid energy consumption is avoided, and the running cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of thermal power generation technology, specifically to a low-temperature precision control indirect cooling tower system and control method. Background Technology

[0002] Indirect cooling towers are prone to freezing during winter operation due to low ambient temperatures, affecting their normal operation. A common method to prevent freezing is to monitor the ambient temperature at the tower's location. When the ambient temperature drops below 5°C, the temperature of the circulating water input to the tower is adjusted to raise the internal temperature and prevent icing. While this method reduces freezing incidents, increasing the circulating water temperature requires increasing the turbine back pressure, leading to higher energy consumption and operating power, thus increasing the turbine's load. Furthermore, under deep-heating conditions, turbine last-stage blade vibration and water erosion increase, shortening the turbine's lifespan and increasing maintenance costs. Summary of the Invention

[0003] To address the problem of high operating and maintenance costs and energy consumption of steam turbine units caused by freezing accidents in indirect cooling towers during winter use, this invention provides a low-temperature precision control indirect cooling tower system and control method.

[0004] To achieve the above objectives, the present invention provides the following technical solution: This invention proposes a low-temperature precision control indirect cooling tower system, including an air-cooled tower, wherein the air-cooled tower integrates a fan-shaped cooling zone; The cooling section of the fan segment is equipped with a cooling assembly, which includes louvers. Each end of the louvers is equipped with a heat exchange tube assembly, and the two heat exchange tube assemblies are arranged in a triangular pattern with the louvers. The water inlets of the heat exchange tube assemblies at both ends of the louvers are connected in series through a first conveying pipe, and the water outlets of the heat exchange tube assemblies at both ends of the louvers are connected in series through a second conveying pipe. A circulating water system is connected between the second conveying pipe and the first conveying pipe. A first pressure transmitter is installed within the triangle near the louver; a second pressure transmitter is installed within the cooling zone of the fan segment, located on the side of the heat exchange tube assembly and away from the louver; the second pressure transmitter, the first pressure transmitter, and the controller of the louver are respectively connected to a control terminal. The control terminal is used to acquire the differential pressure value of the wind pressure collected by the first pressure transmitter and the second pressure transmitter, compare the differential pressure value with the basic differential pressure stored in it, and adjust the opening size of the louver based on the comparison result.

[0005] Preferably, multiple cooling zones are provided, and the multiple cooling zones are arranged in a ring around each other. The first delivery pipes of the cooling components in the multiple cooling zones are connected in series through a first water inlet pipe, and the second delivery pipes of the cooling components in the multiple cooling zones are connected in series through a first water outlet pipe. The circulating water system is connected between the first water inlet pipe and the first water outlet pipe.

[0006] Preferably, each of the sector cooling zones is provided with multiple cooling components, and the multiple cooling components are arranged at equal intervals within the sector cooling zone.

[0007] Preferably, the circulating water system includes a condenser, one end of which is connected to a port on the first water inlet pipe away from the cooling component, and the other end of the condenser is connected to the inlets of multiple water supply control components and the inlet of the recovery system; the outlet of the water supply control components is connected to the port on the first water outlet pipe away from the cooling component. The water supply control assembly includes a first regulating valve, a circulating water pump, and a second regulating valve connected in series.

[0008] Preferably, a control loop is provided between the first water outlet pipe and the second delivery pipe, and between the first water inlet pipe and the first delivery pipe; The control loop includes a fifth control valve and a sixth control valve. One end of the fifth regulating valve is connected to the first inlet pipe, and the other end of the fifth regulating valve is connected to the first delivery pipe; One end of the sixth regulating valve is connected to the first outlet pipe, and the other end of the fifth regulating valve is connected to the second delivery pipe; The sixth regulating valve and the fifth regulating valve are connected to a first side branch pipe near the end port of the second conveying pipe or the first conveying pipe. The first side branch pipe is equipped with a seventh regulating valve and an eighth regulating valve. A second side branch pipe is connected at the position between the seventh regulating valve and the eighth regulating valve on the first side branch pipe. A water supply circuit is connected to the end of the second side branch pipe away from the second conveying pipe or the first conveying pipe.

[0009] Preferably, the water replenishment circuit includes a water storage tank, which is connected to the first outlet pipe and the first inlet pipe via pipelines, and the inlet of the water storage tank is connected to the second delivery pipe and the first delivery pipe via an auxiliary water delivery pipe. A third regulating valve is installed on the pipeline connecting the first water inlet pipe to the water storage tank, and a fourth regulating valve is installed on the pipeline connecting the first water outlet pipe to the water storage tank. An expansion tank is connected to the auxiliary water supply pipe and the first water inlet pipe via a pipeline. A third temperature transmitter is installed on the pipeline between the sixth regulating valve and the first outlet pipe.

[0010] Preferably, the heat exchange tube assembly includes a heat exchange inlet pipe and a heat exchange outlet pipe, and multiple heat exchange tubes are arranged between the heat exchange inlet pipe and the heat exchange outlet pipe. A first temperature transmitter is arranged on the heat exchange tube, and a second temperature transmitter is arranged in the triangle near the louver. The second temperature transmitter and the first temperature transmitter are respectively connected to the control terminal for communication.

[0011] Preferably, multiple wind measurement towers are provided on the side of the air-cooled tower, and wind energy detectors are integrated in the multiple wind measurement towers. The wind energy detectors are communicatively connected to the control terminal. The control terminal controls the opening size of the louvers on the windward and leeward sides of the air-cooled tower based on the wind direction and wind speed collected by the wind energy detectors.

[0012] Preferably, four wind measurement towers are provided, and the four wind measurement towers are evenly arranged around the air-cooled tower.

[0013] This invention proposes a method for regulating the aforementioned low-temperature precision control indirect cooling tower system, comprising: The control terminal acquires the wind pressure collected by the second pressure transmitter and the first pressure transmitter, calculates the differential pressure value between the wind pressure collected by the second pressure transmitter and the first pressure transmitter, and compares the differential pressure value with the basic differential pressure stored in its internal memory. If the differential pressure value is greater than the basic differential pressure, adjust the opening of the louvers to be smaller; if the differential pressure value is less than the basic differential pressure, adjust the opening of the louvers to be larger. Alternatively, the control terminal can acquire the air pressure collected by the second pressure transmitter, calculate the average pressure difference of the air-cooled tower, and generate a control signal based on the air pressure collected by the first pressure transmitter and the differential pressure value between the air pressure collected by the second pressure transmitter and the average pressure difference. The control terminal acquires the status signal of the louvers and adjusts the opening degree of the louvers or the water supply temperature of the circulating water system based on the adjustment signal and the status signal.

[0014] Compared with the prior art, the present invention has the following beneficial technical effects: This invention proposes a low-temperature precision control indirect cooling tower system. In this system, multiple cooling zones arranged in a ring can be independently controlled, avoiding energy waste caused by overall regulation. It can be precisely adapted to the heat exchange needs of different areas, improving system operational flexibility. The cooling components adopt a triangular arrangement of louvers and heat exchange tubes, optimizing the contact path between airflow and heat exchange tubes, increasing heat exchange area and efficiency, reducing the operating load of the circulating water system, and lowering basic energy consumption. By installing a first pressure transmitter inside the cooling components near the louvers, the pressure within the cooling zone can be controlled. A second pressure transmitter is installed on the side of the heat exchange tube assembly, away from the louvers. Based on the air pressure collected by the first pressure transmitter for each cooling component and the differential pressure value collected by the second pressure transmitter for the air pressure in the air-cooled tower and the average pressure difference in the cooling tower, the control terminal precisely adjusts the louver opening to keep the temperature of the heat exchange tube assembly stable in the non-freezing range. This avoids freezing accidents and subsequent maintenance and replacement costs from the root, reduces the workload of operation and maintenance, and combines zoned control with precise temperature control. The operating status of each sector can be dynamically adjusted according to the turbine unit load to avoid ineffective energy consumption and further reduce operating costs.

[0015] Furthermore, the annular symmetrical layout in this system significantly improves the circumferential uniformity of airflow organization inside the air-cooled tower, suppressing ventilation distortion caused by local sector windward or leeward wind conditions; while the main water pipe allows the control terminal to make unified decisions based on global parameters such as total inlet water temperature, total return water temperature, and main pipeline pressure difference, avoiding hydraulic coupling conflicts caused by independent adjustment of each sector, and improving the overall operational stability and response consistency of the system.

[0016] Furthermore, this system constructs a cooling unit array with spatial repeatability and functional independence within the cooling zone of a single fan segment. This forces the airflow to be dispersed into multiple equivalent channels after entering the fan segment, significantly reducing local high-speed jet and vortex accumulation phenomena. Since the geometric parameters, installation posture, and initial opening of each cooling component are consistent, their original wind resistance characteristics are similar, thus exhibiting statistical consistency in response to changes in wind speed and direction. When the external wind environment changes, the wind pressure disturbances experienced by each cooling component change in a similar proportion, providing a reliable comparison benchmark for the control terminal to implement reverse adjustment based on differential pressure deviation. Through the equidistant arrangement at the structural level, the system's robustness to airflow fluctuations is enhanced, reducing the probability of local freezing caused by uneven cooling within the fan segment. At the same time, it provides a basic physical carrier for intelligent control strategies such as on-demand start / stop and gradient adjustment. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a low-temperature precision control indirect cooling tower system proposed in this invention; Figure 2 for Figure 1 A partial schematic diagram of point A in the middle; Figure 3This is a schematic diagram of the structure of a heat exchange tube assembly in a low-temperature precision control indirect cooling tower system proposed in this invention; In the attached diagram: 1. Air-cooled tower; 10. Segment cooling zone; 101. Cooling assembly; 1011. Louver; 1012. Heat exchanger tube assembly; 10121. Heat exchanger inlet pipe; 10122. Heat exchanger outlet pipe; 10123. Heat exchanger tube; 10124. First temperature transmitter; 1013. Second temperature transmitter; 1014. First pressure transmitter; 102. Control loop; 1021. Fifth regulating valve; 1022. Seventh regulating valve; 1023. Eighth regulating valve ; 1024, Sixth regulating valve; 103, Third temperature transmitter; 104, Second pressure transmitter; 105, First regulating valve; 106, Second regulating valve; 11, Water storage tank; 12, Expansion tank; 13, First inlet pipe; 14, First outlet pipe; 15, Auxiliary water supply pipe; 16, Third regulating valve; 17, Fourth regulating valve; 2, Wind measuring tower; 3, Circulating water system; 30, Circulating water pump; 31, Condenser; 32, First regulating valve; 33, Second regulating valve. Detailed Implementation

[0018] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0019] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] In the operation of indirect air-cooled systems in thermal power plants, low temperatures, strong winds, and sudden changes in wind direction during winter lead to uneven ventilation across different sections of the air-cooled tower. This results in a sharp increase in heat exchange intensity on the windward side while airflow stagnates on the leeward side, causing localized temperatures of the heat exchange tube bundles to fall below freezing and increasing the risk of ice formation in the circulating water. Simultaneously, to mitigate freezing risks, existing systems generally employ a conservative strategy of raising the circulating water temperature to 20-25°C, leading to increased turbine back pressure, decreased thermal efficiency, and failure to fully utilize the natural cooling potential in low-temperature environments. The essence of this problem lies in the fact that traditional systems lack real-time quantitative sensing capabilities of the spatial distribution of wind pressure within the tower, and also lack a closed-loop control mechanism based on localized airflow dynamic deviations. This results in coarse ventilation volume adjustments and redundant water temperature settings, making it difficult to achieve a coordinated balance between anti-freezing safety and energy efficiency optimization.

[0025] This invention proposes a low-temperature precision control indirect cooling tower system, such as... Figures 1-3 As shown, it includes an air-cooled tower 1, which integrates a segmented cooling zone 10. The air-cooled tower 1 is a reinforced concrete hyperbolic natural ventilation tower or mechanical ventilation tower, and its interior is divided into multiple independent airflow channels along the circumference. The segmented cooling zone 10 is one of the modular units with complete airflow organization and heat exchange functions.

[0026] Cooling components are installed within the fan-segment cooling zone 10. These components include louvers 1011, which are electrically adjustable multi-blade structures. The blades are made of weather-resistant aluminum alloy or fiberglass, with a single blade length of 0.8–1.2 meters. The opening range is 0° (fully closed) to 90° (fully open), with a response time ≤15 seconds. The louvers are installed on the air inlet side of the fan-segment cooling zone 10 to actively cut off or guide ambient airflow into the cooling area. At each end of the louver 1011, a heat exchange tube assembly 1012 is provided. The heat exchange tube assembly 1012 is a finned tube bundle heat exchanger, with the tube material being TP304 stainless steel or aluminum-manganese alloy, and the fins being high-frequency welded aluminum fins with a fin spacing of 2.5~3.5mm. The two heat exchange tube assemblies 1012 are symmetrically arranged on both sides of the louver 1011, forming an acute-angled triangular airflow channel together with the louver 1011. That is, the two heat exchange tube assemblies 1012 and the louver 1011 form a triangle. The airflow is throttled by louvers 1011 and then accelerated and evenly distributed to the heat exchange tube bundles 1012 on both sides within the triangular area, avoiding airflow deflection and vortex accumulation. The inlets of the heat exchange tube bundles 1012 at both ends of louvers 1011 are connected in series via a first conveying pipe, and the outlets of the heat exchange tube bundles 1012 at both ends of louvers 1011 are connected in series via a second conveying pipe. A circulating water system 3 connects the second conveying pipe and the first conveying pipe. Both the first and second conveying pipes are pressure-bearing stainless steel pipes with a nominal diameter of DN150–DN250 and anti-corrosion passivation treatment on the inner wall. The first and second conveying pipes connect the inlet and outlet ends of the heat exchange tube bundles 1012 on the same side in series, forming a closed water circuit to ensure that the hydraulic conditions of the two heat exchange tube bundles in the same sector are consistent. The first and second conveying pipes can be arranged in a ring or a straight line, and their direction avoids the main support structure inside the tower, with reserved bends for thermal expansion compensation. A first pressure transmitter 1014 is installed on a rigid support 0.3-0.5m from the edge of the louver 1011 within the triangle; a second pressure transmitter 104 is installed on a cantilever support located on the leeward side edge of the heat exchange tube assembly 1012 within the fan-segment cooling zone 10, 0.8-1.2m from the outer surface of the heat exchange tube assembly 1012; the controllers of the second pressure transmitter 104, the first pressure transmitter 1014, and the louver 1011 are respectively connected to a control terminal; in this embodiment, the first pressure transmitter 1014 is a pressure sensor with an accuracy class of 0.1, the second pressure transmitter 104 is a static pressure sensor with an accuracy class of 0.2, and the control terminal is an industrial-grade PLC or DCS controller with a built-in embedded differential pressure calculation module and PID control algorithm, and its communication interface supports HART, Modbus TCP, or Profibus DP protocols. The control terminal is used to determine the average pressure difference inside the air-cooled tower 1 based on the wind pressure collected inside the air-cooled tower 1, and to adjust the opening size of the louver 1011 or the water supply temperature of the circulating water system 3 based on the differential pressure value of the average wind pressure difference collected by the first pressure transmitter 1014.

[0027] This embodiment further provides: multiple cooling zone segments 10 are provided, and the multiple cooling zone segments 10 are equally spaced to form a ring. The first delivery pipes of the cooling components in the multiple cooling zone segments 10 are connected in series through a first water inlet pipe 13, and the second delivery pipes of the cooling components in the multiple cooling zone segments 10 are connected in series through a first water outlet pipe 14. The first water inlet pipe 13 and the first water outlet pipe 14 are connected to a circulating water system 3. By arranging the multiple cooling zone segments 10 in a ring structure with equal spacing and uniformly connecting them to the common first water inlet pipe 13 and first water outlet pipe 14, a centralized hydraulic connection system with a main pipe is formed. Thus, without increasing the control complexity, the coordinated distribution of water volume and the balanced pressure response of the multiple cooling zone segments are achieved. This embodiment further provides that: each fan segment cooling zone 10 is provided with multiple cooling components, which are equally spaced within the fan segment cooling zone 10. By configuring multiple cooling components with the same structure and regular layout within a single fan segment cooling zone 10, and arranging them at equal intervals along the circumference or radial direction of the fan segment, under low temperature and high wind conditions, if only a single cooling component is provided within the fan segment, the airflow is likely to concentrate and penetrate a specific area, causing insufficient ventilation, water accumulation, and a sudden drop in pipe wall temperature in other areas. The equidistant arrangement of multiple components can force the airflow to achieve macroscopic uniform distribution within the fan segment cross-section, providing a physical premise for subsequent zoned fine control based on pressure and temperature feedback.

[0028] This embodiment further provides that: the circulating water system 3 is a closed-loop forced circulation loop, including a condenser 31. One end of the condenser 31 is connected to the port on the first inlet pipe 13 away from the cooling components, and the other end of the condenser 31 is connected to the inlets of multiple water supply control components and the inlet of the recovery system; the outlet of the water supply control components is connected to the port on the first outlet pipe 14 away from the cooling components; the water supply control components include a first regulating valve 32, a circulating water pump 30, and a second regulating valve 38 connected in series. The water supply temperature of the circulating water system 3 is adjusted by adjusting the flow rate or bypass ratio on the cooling side of the condenser 31, with a temperature control accuracy of ±0.3℃ and an adjustable range of 10~35℃. This provides a reliable hardware foundation and controllability for achieving the operating goals of lower back pressure and higher energy efficiency while ensuring antifreeze safety.

[0029] This embodiment further provides: a control loop 102 is provided between the first outlet pipe 14 and the second delivery pipe, and between the first inlet pipe 13 and the first delivery pipe; the control loop 102 includes a fifth control valve 1021 and a sixth control valve 1024, one end of the fifth control valve 1021 is connected to the first inlet pipe 13, and the other end of the fifth control valve 1021 is connected to the first delivery pipe; one end of the sixth control valve 1024 is connected to the first outlet pipe 14, and the other end of the fifth control valve 1021 is connected to the second delivery pipe; the sixth control valve 1024... A first bypass pipe is connected to the end port of the fifth regulating valve 1021 near the second or first delivery pipe. The seventh regulating valve 1022 and the eighth regulating valve 1023 are installed on the first bypass pipe. A second bypass pipe is connected to the first bypass pipe between the seventh regulating valve 1022 and the eighth regulating valve 1023. A water supply circuit is connected to the end of the second bypass pipe away from the second or first delivery pipe. The fifth regulating valve 1021, the sixth regulating valve 1024, the seventh regulating valve 1022, and the eighth regulating valve 1023 are all equipped with valve position feedback modules, which output 4~20 mA analog signals and digital communication interfaces (such as HART or Modbus RTU) and establish a bidirectional communication connection with the control terminal. The control terminal sends opening commands to each valve based on preset logic strategies (such as start-stop sequences, fault diagnosis results, and temperature / pressure over-limit events) and receives real-time valve position status to realize closed-loop monitoring and abnormal alarm of valve action. The control loop 102 enables multi-level, multi-mode, and highly robust control of the hydraulic pathways in multiple cooling components within a single sector's cold zone 10. For example, during the system's cold start-up phase, the control terminal first closes the fifth regulating valve 1021 and the sixth regulating valve 124, and opens the seventh regulating valve 1022 to 30% and the eighth regulating valve 1023 to 10%, allowing a small amount of preheated hot water to enter the water supply loop via the first and second bypass pipes to complete pipeline preheating and venting. After the system pressure stabilizes, the seventh regulating valve 1022 is gradually closed, while the fifth regulating valve 1021 is simultaneously opened to 20%, introducing the main inlet water. When the rate of increase in the outlet water temperature of this sector is detected to be lower than the threshold, the control terminal determines that air blockage exists. In case of danger, the eighth regulating valve 1023 is briefly opened to 50% to create a micro-circulation disturbance through the bypass, driving away residual gas. In extremely cold winter conditions, if the second pressure transmitter 104 of a certain sector continuously shows a sudden increase in wind pressure and the reading of the first temperature transmitter 10124 drops below 3°C, the control terminal closes the fifth regulating valve 1021 and the sixth regulating valve 1024, and fully opens the seventh regulating valve 1022 and the eighth regulating valve 1023, so that the sector enters the minimum flow recirculation mode. At the same time, constant temperature water is introduced through the second bypass pipe to maintain the medium flow velocity in the pipe > 0.3 m / s and the temperature > 2°C, thereby effectively avoiding the risk of local icing of the heat exchange tube group 1012.Because the main passage is composed of the fifth regulating valve 1021 and the sixth regulating valve 1024, rapid isolation and on / off control of the water circuit of the fan section cooling component is achieved; because the first side branch pipe containing the seventh regulating valve 1022 and the eighth regulating valve 1023 and the second side branch pipe connecting the water supply circuit are set, controllable recirculation and dynamic water supply can still be maintained when the main passage is closed, which significantly improves the system's operational safety, adjustment flexibility and antifreeze reliability under complex working conditions.

[0030] This embodiment further provides that: the water replenishment circuit includes a water storage tank 11, the water storage tank 11 is connected to the first water outlet pipe 14 and the first water inlet pipe 13 through pipelines respectively, and the water inlet of the water storage tank 11 is connected to the second delivery pipe and the first delivery pipe through an auxiliary water delivery pipe 15 respectively. A third regulating valve 16 is installed on the pipeline connecting the first inlet pipe 13 and the water storage tank 11; a fourth regulating valve 17 is installed on the pipeline connecting the first outlet pipe 14 and the water storage tank 11; an expansion tank 12 is connected to the auxiliary water supply pipe 15 and the first inlet pipe 13 via a pipeline; a third temperature transmitter 103 is installed on the pipeline between the sixth regulating valve 1024 and the first outlet pipe 14. The third temperature transmitter 103 is a PT100 type armored resistance thermometer with an accuracy class of ±0.15. The temperature (℃) is used to characterize the return water temperature after regulation by control loop 102 in real time. It is one of the key input parameters for determining whether the system has entered the low-temperature antifreeze mode. The temperature signal not only participates in the water replenishment logic, such as triggering the heating start of water storage tank 11 and the flow limiting protection of fourth regulating valve 17 when the reading of the third temperature transmitter 103 is ≤5℃, but also serves as a correction factor for differential pressure regulation. For example, when a sudden drop in return water temperature is detected without a synchronous change in differential pressure, the control terminal determines that there may be signs of local freezing and intervenes in advance to coordinate the opening of the sixth regulating valve 1024 and the fifth regulating valve 1021. As an optional implementation, the third temperature transmitter 103 can also be replaced with an infrared non-contact temperature measurement module, installed on the outside of the pipe wall, suitable for modification scenarios where it is inconvenient to open holes; or a dual-element redundant configuration can be adopted to improve the reliability of temperature measurement under low-temperature conditions.

[0031] This embodiment further provides: the heat exchange tube assembly 1012 includes a heat exchange inlet pipe 10121 and a heat exchange outlet pipe 10122, with multiple heat exchange tubes 10123 arranged between the heat exchange inlet pipe 10121 and the heat exchange outlet pipe 10122. Each heat exchange tube 10123 has a finned tube structure, with the base tube material being TP304 stainless steel, an outer diameter of φ25.4 mm, a wall thickness of 2.0 mm, and aluminum rolled fins with a pitch of 2.5 mm and a fin height of 12 mm. Each heat exchange tube 10123 is arranged at equal intervals along the axial direction of the inlet and outlet pipes, with a spacing of 120–180 mm, forming a tube bundle array with uniform flow resistance characteristics. A first temperature transmitter 10124 is arranged on each heat exchange tube 10123. The first temperature transmitter 10124 is a platinum resistance temperature sensor Pt100, with its sensing element encapsulated in a stainless steel sheath with an outer diameter of φ6 mm and a length of 35 mm. A second temperature transmitter 1013 is installed within the triangle near the louver 1011. The second temperature transmitter 1013 is a radiation-proof air temperature sensor with a double-layer shielded probe. The second temperature transmitter 10124 and the first temperature transmitter 1013 are respectively connected to the control terminal. The first temperature transmitter 10124, located on the heat exchange tube 10123, directly monitors the tube wall temperature change. Installed in a finless area and supplemented with heat conduction enhancement measures, it can quickly and accurately capture the actual temperature drop of the medium inside the tube under low-temperature, high-wind conditions. The second temperature transmitter 1013, positioned within the triangle near the louver 1011 and employing a radiation-proof structure and reasonable spatial positioning, can stably obtain the true temperature of the incoming air, eliminating interference from tube bundle thermal radiation. This avoids the difficulty in early warning of heat exchange tube freezing risks caused by uneven air temperature and localized heat exchange imbalance, thus improving the proactiveness, sensitivity, and positioning accuracy of anti-freezing control.

[0032] This embodiment further provides that: multiple wind measurement towers 2 are arranged on the side of the air-cooled tower 1, and wind energy detectors are integrated in the multiple wind measurement towers 2. The wind energy detectors are communicatively connected to a control terminal. The control terminal adjusts the opening size of the louvers 1011 on the windward and leeward sides of the air-cooled tower 1 based on the wind direction and wind speed collected by the wind energy detectors. Four wind measurement towers 2 are arranged evenly around the air-cooled tower 1.

[0033] This invention proposes a method for precisely controlling a low-temperature indirect cooling tower system, comprising: The control terminal acquires the wind pressure collected by the second pressure transmitter 104 and the first pressure transmitter 1013, calculates the differential pressure value of the wind pressure collected by the second pressure transmitter 104 and the first pressure transmitter 1013, and compares the differential pressure value with the basic differential pressure stored in its internal memory. If the differential pressure value is greater than the basic differential pressure, adjust the opening of louver 1011 to be smaller; if the differential pressure value is less than the basic differential pressure, adjust the opening of louver 1011 to be larger. Alternatively, the control terminal can acquire the air pressure collected by the second pressure transmitter 104, calculate the average pressure difference of the air-cooled tower 1, and generate a control signal based on the air pressure collected by the first pressure transmitter 1013 and the differential pressure value between the air pressure collected by the second pressure transmitter 104 and the average pressure difference. The control terminal acquires the status signal of the louver 1011 and adjusts the opening degree of the louver 1011 or the water supply temperature of the circulating water system 3 based on the adjustment signal and the status signal.

[0034] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0035] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A low-temperature precision control indirect cooling tower system, characterized in that, Includes an air-cooled tower (1), which integrates a sector cooling zone (10). The cooling section (10) is equipped with a cooling assembly, which includes a louver (1011). A heat exchange tube assembly (1012) is provided at both ends of the louver (1011). The two heat exchange tube assemblies (1012) and the louver (1011) are arranged in a triangular configuration. The inlets of the heat exchange tube assemblies (1012) at both ends of the louver (1011) are connected in series through a first conveying pipe. The outlets of the heat exchange tube assemblies (1012) at both ends of the louver (1011) are connected in series through a second conveying pipe. A circulating water system (3) is connected between the second conveying pipe and the first conveying pipe. A first pressure transmitter (1014) is provided within the triangle near the louver (1011); a second pressure transmitter (104) is provided within the fan-segment cooling zone (10) on the side of the heat exchange tube assembly (1012) and away from the louver (1011); the controllers of the second pressure transmitter (104), the first pressure transmitter (1014), and the louver (1011) are respectively connected to a control terminal. The control terminal is used to obtain the differential pressure value of the wind pressure collected by the first pressure transmitter (1014) and the second pressure transmitter (104), compare the differential pressure value with the basic differential pressure stored in it, and adjust the opening size of the louver (1011) based on the comparison result.

2. The low-temperature precision control indirect cooling tower system according to claim 1, characterized in that, Multiple fan segment cooling zones (10) are provided, and the multiple fan segment cooling zones (10) are arranged in a ring around each other. The first delivery pipes of the cooling components in the multiple fan segment cooling zones (10) are connected in series through the first water inlet pipe (13), and the second delivery pipes of the cooling components in the multiple fan segment cooling zones (10) are connected in series through the first water outlet pipe (14). The circulating water system (3) is connected between the first water inlet pipe (13) and the first water outlet pipe (14).

3. The low-temperature precision control indirect cooling tower system according to claim 2, characterized in that, Each of the sector cooling zones (10) is provided with multiple cooling components, and the multiple cooling components are arranged at equal intervals within the sector cooling zones (10).

4. The low-temperature precision control indirect cooling tower system according to claim 3, characterized in that, The circulating water system (3) includes a condenser (31), one end of which is connected to the port of the first water inlet pipe (13) away from the cooling component, and the other end of the condenser (31) is connected to the inlet of a plurality of water supply control components and the inlet of the recovery system; the outlet of the water supply control components is connected to the port of the first water outlet pipe (14) away from the cooling component. The water supply control assembly includes a first regulating valve (32), a circulating water pump (30), and a second regulating valve (38) connected in series.

5. A low-temperature precision control indirect cooling tower system according to claim 4, characterized in that, A control loop (102) is provided between the first water outlet pipe (14) and the second conveying pipe, and between the first water inlet pipe (13) and the first conveying pipe. The control loop (102) includes a fifth control valve (1021) and a sixth control valve (1024). One end of the fifth regulating valve (1021) is connected to the first water inlet pipe (13), and the other end of the fifth regulating valve (1021) is connected to the first delivery pipe; One end of the sixth regulating valve (1024) is connected to the first outlet pipe (14), and the other end of the fifth regulating valve (1021) is connected to the second delivery pipe; The sixth regulating valve (1024) and the fifth regulating valve (1021) are connected to a first side branch pipe near the end port of the second conveying pipe or the first conveying pipe. The first side branch pipe is equipped with a seventh regulating valve (1022) and an eighth regulating valve (1023). A second side branch pipe is connected at the position between the seventh regulating valve (1022) and the eighth regulating valve (1023) on the first side branch pipe. A water supply circuit is connected to the end of the second side branch pipe away from the second conveying pipe or the first conveying pipe.

6. A low-temperature precision control indirect cooling tower system according to claim 5, characterized in that, The water replenishment circuit includes a water storage tank (11), which is connected to the first outlet pipe (14) and the first inlet pipe (13) through pipelines. The inlet of the water storage tank (11) is connected to the second delivery pipe and the first delivery pipe through an auxiliary water delivery pipe (15). A third regulating valve (16) is provided on the pipeline connecting the first water inlet pipe (13) and the water storage tank (11), and a fourth regulating valve (17) is provided on the pipeline connecting the first water outlet pipe (14) and the water storage tank (11). An expansion tank (12) is connected between the auxiliary water supply pipe (15) and the first water inlet pipe (13) via a pipeline. A third temperature transmitter (103) is installed on the pipeline between the sixth regulating valve (1024) and the first outlet pipe (14).

7. A low-temperature precision control indirect cooling tower system according to claim 1, characterized in that, The heat exchange tube assembly (1012) includes a heat exchange inlet pipe (10121) and a heat exchange outlet pipe (10122). A plurality of heat exchange tubes (10123) are arranged between the heat exchange inlet pipe (10121) and the heat exchange outlet pipe (10122). A first temperature transmitter (10124) is arranged on the heat exchange tube (10123). A second temperature transmitter (1013) is arranged in the triangle near the louver (1011). The second temperature transmitter (10124) and the first temperature transmitter (1013) are respectively connected to the control terminal for communication.

8. A low-temperature precision control indirect cooling tower system according to claim 1, characterized in that, Multiple wind measurement towers (2) are provided on the side of the air-cooled tower (1). Each wind measurement tower (2) integrates a wind energy detector. The wind energy detector is connected to the control terminal. The control terminal controls the opening size of the louvers (1011) on the windward and leeward sides of the air-cooled tower (1) based on the wind direction and wind speed collected by the wind energy detector.

9. A low-temperature precision control indirect cooling tower system according to claim 8, characterized in that, Four wind measurement towers (2) are provided, and the four wind measurement towers (2) are evenly arranged around the air-cooled tower (1).

10. A method for regulating a low-temperature precision-controlled indirect cooling tower system according to any one of claims 1 to 9, characterized in that, include: The control terminal acquires the wind pressure collected by the second pressure transmitter (104) and the first pressure transmitter (1013), calculates the differential pressure value of the wind pressure collected by the second pressure transmitter (104) and the first pressure transmitter (1013), and compares the differential pressure value with the basic differential pressure stored in its internal memory. If the differential pressure value is greater than the basic differential pressure, then reduce the opening of the louver (1011); if the differential pressure value is less than the basic differential pressure, then increase the opening of the louver (1011). Alternatively, the control terminal can obtain the wind pressure collected by the second pressure transmitter (104), calculate the average pressure difference of the air-cooled tower (1), and generate a control signal based on the wind pressure collected by the first pressure transmitter (1013) and the differential pressure value between the wind pressure collected by the second pressure transmitter (104) and the average pressure difference. The control terminal obtains the status signal of the louver (1011) and adjusts the opening size of the louver (1011) or the water supply temperature of the circulating water system (3) based on the adjustment signal and the status signal.

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