Multi-branch parallel evaporative cooling system and control method

Abstract

The application provides a multi-branch parallel evaporative cooling system and a control method, and relates to the technical field of industrial evaporative cooling systems. The multi-branch parallel evaporative cooling system control method comprises the following steps: S10, setting a target temperature T0 of an outlet header; S20, detecting a real-time temperature T1 of the outlet header in real time; S30, controlling the real-time temperature T1 to approach the target temperature T0 by adjusting the total working frequency of the fan; wherein S30 comprises the following steps: setting a first variable frequency fan; when the real-time temperature T1 is greater than the target temperature T0, sequentially starting the first variable frequency fan, a power frequency fan and the remaining variable frequency fans; until the real-time temperature T1 is equal to the target temperature T0 or the total working frequency of the fan reaches a maximum value; when the real-time temperature T1 is less than the target temperature T0, sequentially closing the remaining variable frequency fans, the power frequency fan and the first variable frequency fan; until the real-time temperature T1 is equal to the target temperature T0 or all the fans are turned off; and the application can improve the degree of automation, reduce energy consumption and reduce system fluctuations.

Description

Technical Field

[0001] This invention relates to the field of industrial evaporative cooling system technology, specifically to a multi-branch parallel evaporative cooling system and its control method. Background Technology

[0002] Evaporative cooling is a process that uses water evaporation and forced air circulation to remove heat. It is widely used in many industries such as petrochemicals, light industry, pharmaceuticals, refrigeration and air conditioning, and food refrigeration, and is typically suitable for large and medium-sized refrigeration units. With the rapid scaling up and increasing production capacity across industries, evaporative cooling is becoming increasingly common for cooling equipment to reduce overall energy consumption.

[0003] Evaporative cooling technology is widely used in the crystalline silicon industry. Currently, the industry prioritizes the safe and stable operation of equipment, and reducing manual labor intensity and increasing automation have become key drivers of development. The level of automation control in these systems is steadily improving, ensuring stable operation and reducing operator workload. For evaporative cooling systems involving multiple pumps and fans, and operating modes that utilize variable frequency fans to control outlet temperature, engineers are researching and developing comprehensive DCS (Distributed Control System) control schemes that comprehensively consider energy consumption, heat exchange performance, and fluid dynamics. This enhances the automation level of the entire fan system and stabilizes the target temperature within the ideal range. Meanwhile, intensifying competition in the crystalline silicon industry makes improving product quality and reducing unit operating costs paramount.

[0004] In the high-capacity crystalline silicon industry, evaporative cooling is increasingly used. For example, in the evaporative cooling process at the top of the coupled tower in a distillation unit, the cooling equipment consists of a water spray system supplemented by air-cooled fans, with as many as 24 fans or even more, and the ratio of fixed-frequency fans to variable-frequency fans reaching 1:1. Currently, the most commonly used operating scheme is a single-branch control logic, where the variable-frequency fans on each branch control the temperature of the corresponding branch pipe by synchronously adjusting the frequency of the variable-frequency fans. This requires all variable-frequency fans in each branch to be running. Since both the fans and the frequency converters consume electricity, this scheme inevitably consumes a large amount of energy. Secondly, with fluctuations in the operating load of the unit or changes in ambient temperature, the fixed-frequency fans on each branch need to be manually started and stopped. Moreover, the starting and stopping of the fixed-frequency fans will cause significant fluctuations in the temperature of the main material outlet pipe, leading to large fluctuations in the unit's operating parameters and even causing unstable product quality. The manual starting and stopping of the fixed-frequency fans also increases the labor intensity of operators, consuming a lot of time and energy. Therefore, the single-loop control scheme of the evaporative cooling system has a low degree of automation, which is very detrimental to the stable operation of the system. For devices with multiple evaporative cooling systems, such as those in the crystalline silicon industry, it will undoubtedly consume a lot of manpower in operation and adjustment. Summary of the Invention

[0005] To address the problem that the single-loop control scheme of the existing evaporative cooling system has a low degree of automation and is very detrimental to the stable operation of the system, this invention provides a multi-branch parallel evaporative cooling system and control method that can improve the automation level of the frequency conversion control of the evaporative cooling system, reduce energy consumption, and reduce system fluctuations.

[0006] The technical solution adopted in this invention is:

[0007] A control method for a multi-branch parallel evaporative cooling system, using an evaporative cooling system comprising multiple parallel cooling branches, each cooling branch equipped with multiple fans, including both fixed-frequency fans and variable-frequency fans, the control method for the multi-branch parallel evaporative cooling system comprising the following steps:

[0008] S10. Set the target temperature T0 of the outlet manifold of the evaporative cooling system;

[0009] S20. Real-time monitoring of the real-time temperature T1 of the outlet manifold of the evaporative cooling system;

[0010] S30. The real-time temperature T1 is controlled by adjusting the total operating frequency of the fan to make it approach the target temperature T0;

[0011] Wherein, S30 includes:

[0012] Set the first variable frequency fan;

[0013] When the real-time temperature T1 is greater than the target temperature T0, the first variable frequency fan, the power frequency fan, and the other variable frequency fans except the first variable frequency fan are started in sequence until the real-time temperature T1 equals the target temperature T0 or the total operating frequency of the fans reaches its maximum value. When the real-time temperature T1 is less than the target temperature T0, the other variable frequency fans except the first variable frequency fan, the power frequency fan, and the first variable frequency fan are turned off in sequence until the real-time temperature T1 equals the target temperature T0 or all the fans are turned off.

[0014] Furthermore, S30 includes: starting the next fan after all the operating variable frequency fans have reached their maximum operating frequency; and shutting down the operating fans after they have reached their minimum operating frequency.

[0015] Furthermore, when the power frequency fan starts, the first variable frequency fan quickly drops to the minimum operating frequency; when the power frequency fan stops, the first variable frequency fan quickly rises to the maximum operating frequency; and all variable frequency fans start at the minimum operating frequency.

[0016] Furthermore, S30 includes: starting the power frequency fan and the remaining variable frequency fans except the first variable frequency fan, according to the order of the number of fans started on the multiple cooling branches from few to many.

[0017] Furthermore, it also includes the following steps:

[0018] S12. Set the flow deflection of multiple cooling branches according to the piping structure of the evaporative cooling system;

[0019] Furthermore, the first variable frequency fan is positioned on the cooling branch with the largest flow deviation, and S30 includes:

[0020] According to the order of the flow deflection of the multiple cooling branches from large to small, turn on the mains frequency fan and the other variable frequency fans except the first variable frequency fan; according to the order of the flow deflection of the multiple cooling branches from small to large, turn off the mains frequency fan and the other variable frequency fans except the first variable frequency fan.

[0021] Furthermore, it also includes the following steps:

[0022] S22. Real-time monitoring of the outlet flow rates of multiple cooling branches of the evaporative cooling system;

[0023] Furthermore, the first variable frequency fan is located on the cooling branch with the largest outlet flow rate, and S30 includes:

[0024] According to the order of the outlet flow of the multiple cooling branches from large to small, start the mains frequency fan and the other variable frequency fans except the first variable frequency fan;

[0025] According to the order of increasing outlet flow of the multiple cooling branches, the mains frequency fan and the other variable frequency fans except the first variable frequency fan are shut down.

[0026] Furthermore, the variable frequency fan with the smallest distance from the outlet main pipe on the cooling branch is designated as the first variable frequency fan, and S30 includes:

[0027] On each of the cooling branches, the mains frequency fans and the other variable frequency fans except the first variable frequency fan are turned on in order of increasing distance between the fan and the outlet main pipe;

[0028] On each of the cooling branches, the mains frequency fans and the remaining variable frequency fans except the first variable frequency fan are shut down in descending order of distance between the fan and the outlet main pipe.

[0029] Furthermore, it also includes the following steps:

[0030] S24. Real-time monitoring of the temperature T2 at the corresponding point of each fan on the cooling branch;

[0031] Furthermore, the variable frequency fan with the smallest difference between the corresponding temperature T2 and the real-time temperature T1 is designated as the first variable frequency fan, and S30 includes:

[0032] On each of the cooling branches, the mains frequency fan and the other variable frequency fans except the first variable frequency fan are turned on in ascending order of the difference between the corresponding temperature T2 and the real-time temperature T1.

[0033] On each of the cooling branches, the mains frequency fan and the other variable frequency fans except the first variable frequency fan are turned off in descending order of the difference between the corresponding temperature T2 and the real-time temperature T1.

[0034] A multi-branch parallel evaporative cooling system, comprising:

[0035] The working unit has multiple parallel cooling branches, each equipped with an evaporative cooling water tank, multiple spray water pumps, and multiple fans, including both power frequency fans and variable frequency fans.

[0036] The setting unit can set the target temperature T0 of the outlet manifold of the working unit;

[0037] The detection unit includes a second temperature sensor installed in the outlet manifold of the working unit, which can detect the real-time temperature T1 of the outlet manifold of the working unit in real time.

[0038] The adjustment unit is electrically connected to the working unit, the setting unit, and the detection unit. It can adjust the total operating frequency of the fan to control the real-time temperature T1, making it approach the target temperature T0, and can set the first variable frequency fan.

[0039] When the real-time temperature T1 is greater than the target temperature T0, the adjustment unit can sequentially start the first variable frequency fan, the power frequency fan, and the other variable frequency fans except the first variable frequency fan; until the real-time temperature T1 equals the target temperature T0 or the total operating frequency of the fans reaches its maximum value.

[0040] When the real-time temperature T1 is less than the target temperature T0, the regulating unit can sequentially shut down the remaining variable frequency fans except for the first variable frequency fan, the power frequency fan, and the first variable frequency fan; until the real-time temperature T1 equals the target temperature T0 or all fans are shut down.

[0041] Furthermore, the detection unit also includes:

[0042] Multiple third temperature sensors are installed at corresponding locations on the cooling branches of each fan in the evaporative cooling system, and can detect the temperature at the corresponding locations on the cooling branches of each fan in the evaporative cooling system; and

[0043] Multiple flow sensors are installed at the outlets of multiple cooling branch lines to detect the flow rate at the outlets of multiple cooling branch lines.

[0044] The beneficial effects of this invention are:

[0045] 1. The control method of the present invention adopts the method of detecting and controlling the outlet main pipe temperature of the evaporative cooling system, and integrates the fans of different cooling branches in the entire evaporative cooling system for overall control. By setting the start-up and shutdown sequence of the first variable frequency fan and the fixed frequency fan and variable frequency fan, the overall energy consumption of the evaporative cooling system is reduced and the temperature regulation is stable. This solves the problem that the single-loop control scheme of the evaporative cooling system in the prior art has a low degree of automation and is very detrimental to the stable operation of the system.

[0046] 2. The control method of the present invention only requires the operator to set the target temperature T0 and start the system, and the system can automatically perform efficient temperature control, which greatly simplifies the operation steps and saves labor costs;

[0047] 3. The evaporative cooling system of the present invention detects and controls the outlet main pipe temperature of the evaporative cooling system by setting a setting unit and a detection unit, integrates and controls the fans of different cooling branches in the entire evaporative cooling system, and controls the operation of the working unit by adjusting the start and stop sequence of the first variable frequency fan and the fixed frequency fan and the variable frequency fan set by the adjustment unit. This realizes the reduction of the overall energy consumption of the evaporative cooling system and the stabilization of temperature regulation, and solves the problem that the single-loop control scheme of the existing evaporative cooling system has a low degree of automation and is very detrimental to the stable operation of the system. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 This is a flowchart of the control method of the present invention;

[0050] Figure 2 This is a schematic diagram of the evaporative cooling system according to an embodiment of the present invention;

[0051] Figure 3 This is a schematic diagram of the structure of an existing evaporative cooling system;

[0052] Figure 4 This is a schematic diagram of the working unit of Embodiment 1 of the present invention;

[0053] Figure 5This is a schematic diagram of the working unit during maintenance according to Embodiment 1 of the present invention;

[0054] Figure 6 This is a schematic diagram of the working unit of Embodiment 3 of the present invention.

[0055] Attached reference numerals: 100 - working unit, 110 - inlet main pipe, 120 - cooling branch, 130 - outlet main pipe;

[0056] 200-Setting Unit;

[0057] 300-Detection Unit;

[0058] 400-Adjustment unit;

[0059] AC01a~AC01b - Two evaporative cooling water tanks, LT01a~LT01b - Two level gauges, LV01a~LV01b - Two water supply regulating valves, P01a~P01f - Six spray water pumps, F01~F24 - 24 fans, TT01a~TT01f - Six first temperature sensors, TT02 - Second temperature sensor, TS01a~TS01f - Six flow sensors. Detailed Implementation

[0060] 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 are not intended to 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.

[0061] The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, these are merely examples and are not intended to limit the present invention.

[0062] The embodiments of the invention will now be described in detail with reference to the accompanying drawings.

[0063] Evaporative cooling equipment is widely used, such as the evaporative cooling system at the top of the coupled tower in the distillation unit of the crystalline silicon industry. This system is an evaporative cooling system with multiple branches connected in parallel. Its cooling equipment consists of a water spray system supplemented by air-cooled fans, with up to 24 fans distributed across six branches. More fans may be designed for special needs, with the ratio of fixed-frequency fans to variable-frequency fans reaching 1:1. The current operation control method involves keeping all variable-frequency fans in each branch running, such as... Figure 3 As shown, the temperature control logic is as follows: the frequency of the variable frequency fan on each branch and the on / off state frequency fan are adjusted to ensure that the outlet material temperature of each branch reaches the required temperature. However, during the adjustment process, since each branch relies on the variable frequency fan to control the operating frequency of the evaporative cooling system, each branch's variable frequency fan needs to be running for adjustment. This increases the power consumption of the variable frequency fan's inverter, resulting in higher energy consumption for the evaporative cooling system. Furthermore, the switching on and off of the state frequency fan can easily cause significant fluctuations in the operating frequency of the entire evaporative cooling system, leading to large fluctuations in the material temperature output from the main material outlet pipe of the evaporative cooling system. This simultaneously affects the system's stability and product quality.

[0064] Please see Figure 1 This invention proposes a control method for a multi-branch parallel evaporative cooling system, used for frequency conversion control of such systems. This method unifies the operation of both fixed-frequency and variable-frequency fans in different branches, directly controlling the temperature of the system's outlet manifold. This improves the automation level of the frequency conversion control, reduces energy consumption, and minimizes system fluctuations. The method utilizes an evaporative cooling system with multiple parallel cooling branches, each equipped with multiple fans, including both fixed-frequency and variable-frequency fans. Figure 1 As shown, the control method of this multi-branch parallel evaporative cooling system mainly includes the following steps:

[0065] S10. Set the target temperature T0 for the outlet main pipe of the evaporative cooling system. This step can be set before running the evaporative cooling system, or it can be set or changed during operation. During the operation of the evaporative cooling system, the material to be cooled is introduced into the pipelines of each cooling branch, and the spray pump and the fan are started simultaneously to carry out evaporative cooling.

[0066] S20. Real-time detection of the real-time temperature T1 of the outlet manifold of the evaporative cooling system. In this invention, the evaporative cooling system is equipped with a second temperature sensor on its material outlet manifold to detect the material temperature output by the material outlet manifold in real time, i.e., the real-time temperature T1 of the outlet manifold. Therefore, the fan power of the evaporative cooling system can be increased or decreased according to the difference between the real-time temperature T1 of the outlet manifold and the target temperature T0 of the outlet manifold.

[0067] S30. Control the real-time temperature T1 by adjusting the total operating frequency of the fan to bring it closer to the target temperature T0. Adjusting the total operating frequency of the fan mainly includes controlling the fan's on / off state and adjusting the operating frequency of the variable frequency fan.

[0068] In step S30, by designating one variable frequency fan in the system as the first variable frequency fan and starting it first, the overall operating frequency of the system can be smoothly adjusted during both increases and decreases using the first variable frequency fan. Next, when the real-time temperature T1 is greater than the target temperature T0, the first variable frequency fan is started first, followed by multiple fixed-frequency fans, and finally the remaining variable frequency fans (excluding the first variable frequency fan) are started sequentially. The fans are stopped when the real-time temperature T1 equals the target temperature T0 or the total operating frequency of the fans reaches its maximum value. During the cooling process, the real-time temperature T1 may equal the target temperature T0 when only the first variable frequency fan is running; it may also equal the target temperature T0 when the first variable frequency fan and one or more fixed frequency fans are running; or it may equal the target temperature T0 when the first variable frequency fan, all fixed frequency fans, and one or more other variable frequency fans are running. During the adjustment process, all variable frequency fans except the first variable frequency fan are set to start last, thereby reducing the number of variable frequency fans running during the variable frequency temperature control of the evaporative cooling system, reducing inverter energy consumption, and achieving energy saving and consumption reduction. If all fans are running and the total operating frequency reaches its maximum value, but the real-time temperature T1 still has not reached the target temperature T0, the fan operating frequency cannot be further adjusted. In this case, the real-time temperature T1 can be further adjusted by adjusting other temperature control methods. When the real-time temperature T1 is lower than the target temperature T0, the remaining variable frequency fans (excluding the first variable frequency fan) are shut down sequentially, followed by the shutdown of multiple fixed frequency fans, and finally the first variable frequency fan. This process continues until the real-time temperature T1 equals the target temperature T0 or all fans are shut down. During the heating process, the real-time temperature T1 may equal the target temperature T0 when only one or more of the remaining variable frequency fans are shut down; it may also equal the target temperature T0 when all the remaining variable frequency fans are shut down and one or more fixed frequency fans are running; or it may equal the target temperature T0 when only the first variable frequency fan is running. In this adjustment process, all variable frequency fans except the first one are set to be shut down first, thereby reducing the number of variable frequency fans operating during the evaporative cooling system's variable frequency temperature control, achieving energy saving and consumption reduction. If the real-time temperature T1 still has not reached the target temperature T0 when all fans are shut down, and the fan operating frequency cannot be further adjusted, the real-time temperature T1 can be further adjusted by using other temperature control methods.

[0069] During the operation of the evaporative cooling system, steps S10 can be repeated according to the needs of the production process to reset the target temperature T0 of the outlet main pipe, and then steps S20 and S30 can be repeated, and the temperature detection and control and adjustment of the total operating frequency of the fan can be repeated.

[0070] In summary, the control method for a multi-branch parallel evaporative cooling system in this invention employs the detection and control of the outlet main pipe temperature of the evaporative cooling system. It integrates and controls the fans of different cooling branches within the entire evaporative cooling system as a whole. By setting the start-up and shutdown sequence of the first variable frequency fan and the fixed frequency fan relative to the variable frequency fan, the overall energy consumption of the evaporative cooling system is reduced, and temperature regulation is stabilized. This solves the problem of low automation in existing single-loop control schemes for evaporative cooling systems, which is detrimental to stable system operation. Furthermore, for operators, existing evaporative cooling system control methods require separate control of multiple cooling branches and multiple fans. In contrast, the control method of this invention only requires the operator to set the target temperature T0 and start the system; the system then automatically performs efficient temperature control, significantly simplifying the operation and saving labor costs.

[0071] Example 1

[0072] According to the control method of the multi-branch parallel evaporative cooling system proposed in this invention, this embodiment provides a multi-branch parallel evaporative cooling system for the evaporative cooling process at the top of the coupling column in a distillation unit in the crystalline silicon industry. During system frequency adjustment, the power frequency fans and variable frequency fans of different branches can be uniformly coordinated and operated, directly controlling the temperature of the system outlet main pipe 130°C. This improves the automation level of the frequency conversion control of the evaporative cooling system, reduces energy consumption, and minimizes system fluctuations. Please refer to... Figures 2-5 The multi-branch parallel evaporative cooling system mainly includes a working unit 100, a setting unit 200, a detection unit 300, and an adjustment unit 400.

[0073] Working unit 100 is used for transporting and temperature regulating the fluid material to be cooled. For example... Figure 4As shown, the working unit 100 has six parallel cooling branches 120. The inlets of the six parallel cooling branches 120 are connected to a common inlet manifold 110, and the outlets of the six parallel cooling branches 120 are connected to a common outlet manifold 130. Furthermore, the cooling branches 120 are equipped with two evaporative cooling water tanks AC01a~AC01b, six spray water pumps P01a~P01f, and 24 fans F01~F24. The evaporative cooling water tanks AC01a and AC01b are each equipped with level gauges, including two level gauges LT01a~LT01b, and the water supply pipes of the evaporative cooling water tanks AC01a and AC01b are each equipped with a water supply regulating valve, including two water supply regulating valves LV01a~LV01b. Figure 3 As shown, the liquid level control logic in this embodiment is as follows: the real-time liquid level is detected by the liquid level gauge and fed back to the water supply regulating valve, which adjusts and controls the liquid level of the evaporative cooling water tank to meet the usage requirements. Among the six spray pumps P01a~P01f, spray pumps P01a, P01b, and P01c are connected to the evaporative cooling water tank AC01a; spray pumps P01d, P01e, and P01f are connected to the evaporative cooling water tank AC01b. Each spray pump sprays one cooling branch 120 to provide evaporative-cooled liquid. Simultaneously, among the 24 fans F01~F24, odd-numbered fans are variable frequency fans, and even-numbered fans are fixed frequency fans. Each cooling branch 120 is equipped with four fans, including two fixed frequency fans and two variable frequency fans. The fans can increase the airflow speed around the cooling branch 120, accelerating the evaporation rate of the liquid and thus reducing the material temperature. When the material temperature needs to be relatively increased, the running fan is turned off or the frequency of the variable frequency fan is reduced; when the material temperature needs to be relatively decreased, the non-running fan is turned on or the frequency of the variable frequency fan is increased. In this embodiment, the minimum operating frequency of the variable frequency fan is 20Hz and the maximum operating frequency is 50Hz.

[0074] The setting unit 200 is part of the DCS control module and can set the target temperature T0 of the outlet manifold 130 of the working unit 100. Furthermore, the setting unit 200 can set or change the target temperature T0 before or during system operation.

[0075] The detection unit 300 is also part of the DCS control module. The detection unit 300 mainly includes a second temperature sensor TT02 installed on the outlet manifold 130 of the working unit 100. This sensor can detect the real-time temperature T1 of the outlet manifold 130 of the working unit 100, allowing for further setting of the fan power of the evaporative cooling system based on the difference between the real-time temperature T1 and the target temperature T0 of the outlet manifold. Additionally, the detection unit 300 in this embodiment also includes six first temperature sensors TT01a~TT01f installed at the outlets of multiple cooling branches 120 of the working unit 100. The real-time detection values ​​of the first temperature sensors are not used as target parameters for system adjustment, but only as reference parameters, facilitating timely detection and handling by operators when localized temperature anomalies occur in the system.

[0076] The regulating unit 400 is also part of the DCS control module. The regulating unit 400 is electrically connected to the working unit 100, the setting unit 200, and the detection unit 300, and can transmit detection and control signals to each other, thereby adjusting the total operating frequency of the fan to control the real-time temperature T1, bringing it closer to the target temperature T0. Simultaneously, the regulating unit 400 can also adjust the spray speed of the spray pump to assist in controlling the cooling efficiency of the evaporative cooling system.

[0077] In this embodiment, the adjustment procedure of the adjustment unit 400 is as follows: one variable frequency fan in the system is set as the first variable frequency fan and is started first, thereby ensuring that the overall operating frequency of the system can be smoothly changed through the first variable frequency fan during the adjustment process of increasing and decreasing. Then, when the real-time temperature T1 is greater than the target temperature T0, the first variable frequency fan is started first, followed by the sequential start of multiple power frequency fans, and finally the remaining variable frequency fans except the first variable frequency fan are started in sequence; the fans are stopped when the real-time temperature T1 equals the target temperature T0 or the total operating frequency of the fans reaches its maximum value. During the cooling process, the real-time temperature T1 may equal the target temperature T0 when only the first variable frequency fan is running; alternatively, the real-time temperature T1 may equal the target temperature T0 when only the first variable frequency fan and one or more fixed frequency fans are running; or the real-time temperature T1 may equal the target temperature T0 when the first variable frequency fan, all fixed frequency fans, and one or more other variable frequency fans are running. During the adjustment process, all variable frequency fans except the first variable frequency fan are set to start last, thereby reducing the number of variable frequency fans running during the variable frequency temperature control of the evaporative cooling system and achieving energy saving and consumption reduction. If all fans are running and the total operating frequency reaches its maximum value, but the real-time temperature T1 still has not reached the target temperature T0, the fan operating frequency cannot be further adjusted. In this case, the real-time temperature T1 can be further adjusted by using other temperature control methods. When the real-time temperature T1 is less than the target temperature T0, the remaining variable frequency fans (excluding the first variable frequency fan) are shut down sequentially, followed by multiple fixed frequency fans, and finally the first variable frequency fan. This process continues until the real-time temperature T1 equals the target temperature T0 or all fans are shut down. During the heating process, the real-time temperature T1 may equal the target temperature T0 when only one or more of the remaining variable frequency fans are shut down; it may also equal the target temperature T0 when all the remaining variable frequency fans are shut down and one or more fixed frequency fans are running; or it may equal the target temperature T0 when only the first variable frequency fan is running. In this adjustment process, all variable frequency fans except the first one are set to be shut down first, thus reducing the number of variable frequency fans operating during the evaporative cooling system's variable frequency temperature control, reducing inverter energy consumption, and achieving energy saving. If the real-time temperature T1 still has not reached the target temperature T0 when all fans are shut down, and the fan operating frequency cannot be further adjusted, the real-time temperature T1 can be further adjusted by using other temperature control methods.

[0078] In summary, in this embodiment, the multi-branch parallel evaporative cooling system uses a setting unit 200 and a detection unit 300 to detect and control the outlet main pipe temperature of the evaporative cooling system. It integrates and controls the fans of different cooling branches 120 throughout the entire evaporative cooling system, and controls the operation of the working unit 100 by adjusting the start-up and shutdown sequence of the first variable frequency fan, the fixed frequency fan, and the variable frequency fan as set by the adjustment unit 400. This achieves a reduction in overall energy consumption and stable temperature regulation of the evaporative cooling system, solving the problem of low automation in existing single-loop control schemes for evaporative cooling systems, which is detrimental to stable system operation. Furthermore, for operators, existing evaporative cooling systems require operators to control multiple cooling branches and multiple fans separately. In contrast, the multi-branch parallel evaporative cooling system in this embodiment only requires the operator to set the target temperature T0 and start the system; the system automatically and efficiently controls the temperature, significantly simplifying the operation and saving labor costs.

[0079] Meanwhile, the adjustment program of the adjustment unit 400 in this embodiment also includes: starting the next fan after all the operating variable frequency fans have reached their maximum operating frequency of 50Hz; and shutting down the operating fans after they have reached their minimum operating frequency of 20Hz. This program executes the frequency conversion adjustment of the operating variable frequency fans before the start-up of the non-operating fans and the shutdown of the already operating fans, thereby making the change in the total operating frequency of the fans smoother and reducing the system temperature fluctuation.

[0080] Furthermore, the adjustment program of the adjustment unit 400 includes: when the fixed frequency fan starts, the first variable frequency fan quickly drops to the minimum operating frequency of 20Hz, with the frequency reduction process typically controlled within 2 seconds, preferably within 1 second. When the fixed frequency fan stops, the first variable frequency fan quickly rises to the maximum operating frequency of 50Hz, with the frequency rise process typically controlled within 2 seconds, preferably within 1 second. Moreover, all variable frequency fans start at the minimum operating frequency of 20Hz. This achieves a frequency adjustment process similar to "stepless speed regulation," preventing significant fluctuations in the system caused by the fixed frequency fan during start-up and shutdown.

[0081] Since only the first variable frequency fan is present in the cooling branch 120 when the industrial frequency fan is turned on, in order to balance the number of fans on each cooling branch 120 and reduce the difference in cooling effect between each cooling branch 120, the adjustment program of the adjustment unit 400 also includes: turning on the industrial frequency fan and the other variable frequency fans except the first variable frequency fan according to the order of the number of fans started in the multiple cooling branches 120 from the fewest to the most, so that the industrial frequency fans on the other cooling branches 120 are started first, the working frequency of the fans in each branch is more balanced, and the temperature difference between each branch is avoided, so as to avoid large temperature fluctuations at the material mixing point of the outlet main pipe 130, which would affect the product quality.

[0082] In this embodiment, the order in which the fans on different cooling branches 120 are turned on, as well as the order in which different fans on the same cooling branch 120 are turned on, are further defined. First, for different cooling branches 120, the flow rate of multiple cooling branches 120 is pre-set according to the piping structure of the evaporative cooling system, such as... Figure 4 As shown in the diagram, based on the flow deviation phenomenon of the parallel branch fluids in the structure, it can be analyzed that the flow rate of the cooling branch 120 is greater closer to the central inlet main pipe 110. Therefore, the flow deviation is set from large to small according to the distance from each cooling branch 120 to the central inlet main pipe 110 from small to large. Furthermore, the adjustment program of the adjustment unit 400 also includes: turning on the fixed frequency fan and the other variable frequency fans except the first variable frequency fan according to the order of the flow deviation of the multiple cooling branches 120 from large to small; turning off the fixed frequency fan and the other variable frequency fans except the first variable frequency fan according to the order of the flow deviation of the multiple cooling branches 120 from small to large. This turn-on sequence helps to quickly improve the cooling effect of the cooling branch 120 with large flow rate and improves the overall working efficiency of the evaporative cooling system. Secondly, on the same cooling branch 120, the variable frequency fan with the smallest distance from the outlet main pipe 130 of the evaporative cooling system on the cooling branch 120 is set as the first variable frequency fan, and the adjustment procedure of the adjustment unit 400 includes: on each cooling branch 120, according to the order of the distance between the fan and the outlet main pipe 130 of the evaporative cooling system from small to large, the industrial frequency fan and the other variable frequency fans except the first variable frequency fan are turned on; on each cooling branch 120, according to the order of the distance between the fan and the outlet main pipe 130 of the evaporative cooling system from large to small, the industrial frequency fan and the other variable frequency fans except the first variable frequency fan are turned off. Since the material temperature is usually higher the further away from the outlet manifold 130, the efficiency of cooling by air contact is higher, which can make full use of natural air cooling and reduce operating energy consumption; the material temperature is usually lower the closer to the outlet manifold 130, the efficiency of cooling by air contact is lower, and the overall cooling effect of adding air cooling is significantly improved. Therefore, this start-up sequence makes full use of the combination of air cooling and evaporative cooling, reducing the energy consumption of the evaporative cooling system.

[0083] It should also be noted that in one or more embodiments, the number of cooling branches 120 can be 3, 4, 5, or more; the number of industrial frequency fans and variable frequency fans on each cooling branch 120 can also be 3, 4, 5, or more; and the ratio of industrial frequency fans to variable frequency fans can also be adjusted as needed, such as 2:1, 1:2, etc. The number of evaporative cooling water tanks and spray water pumps is adapted to the number of cooling branches 120 and the wiring configuration.

[0084] Example 2

[0085] According to the control method of the multi-branch parallel evaporative cooling system proposed in this invention, and the multi-branch parallel evaporative cooling system provided in Embodiment 1, this embodiment provides a control method for a multi-branch parallel evaporative cooling system applied in the multi-branch parallel evaporative cooling system of Embodiment 1. The control method for this multi-branch parallel evaporative cooling system mainly includes the following steps:

[0086] S10. Set the target temperature T0 of the outlet manifold 130 of the evaporative cooling system through the setting unit 200. This step can be set before running the working unit 100, or it can be set or changed during the operation of the working unit 100. During the operation of the working unit 100, the material to be cooled is introduced into the pipelines of each cooling branch, and the spray pump and the fan are started simultaneously to perform evaporative cooling.

[0087] S20. The real-time temperature T1 of the outlet manifold 130 of the evaporative cooling system is detected in real time by the second temperature sensor TT02 of the detection unit 300.

[0088] S30. The regulating unit 400 controls the real-time temperature T1 by adjusting the total operating frequency of the fans, making it approach the target temperature T0. S30 includes: the regulating unit 400 setting the first variable frequency fan. S30 also includes: when the real-time temperature T1 is greater than the target temperature T0, the regulating unit 400 controls the working unit 100 to sequentially start the first variable frequency fan, the power frequency fan, and the remaining variable frequency fans except the first variable frequency fan; until the real-time temperature T1 equals the target temperature T0 or the total operating frequency of the fans reaches its maximum value; when the real-time temperature T1 is less than the target temperature T0, the regulating unit 400 controls the working unit 100 to sequentially shut down the remaining variable frequency fans except the first variable frequency fan, the power frequency fan, and the first variable frequency fan; until the real-time temperature T1 equals the target temperature T0 or all fans are shut down.

[0089] Meanwhile, S30 of this embodiment also includes: starting the next fan after all the operating variable frequency fans have reached their maximum operating frequency; and shutting down the operating variable frequency fans after they have reached their minimum operating frequency. This step executes the frequency conversion adjustment of the operating variable frequency fans before the start-up of the non-operating fans and the shutdown of the already operating fans, thereby making the change in the total operating frequency of the fans smoother and reducing system temperature fluctuations. Furthermore, when the power frequency fan starts, the first variable frequency fan quickly drops to its minimum operating frequency; when the power frequency fan stops, the first variable frequency fan quickly rises to its maximum operating frequency; and all variable frequency fans start at their minimum operating frequency, thereby achieving a frequency adjustment process similar to "stepless speed regulation," preventing large fluctuations in the system caused by the power frequency fans during start-up and shutdown. In addition, based on the order of the number of fans started in the multiple cooling branches 120 from few to many, the mains frequency fans and the other variable frequency fans except the first variable frequency fan are turned on, so that the working frequency of the fans in each branch is more balanced, avoiding excessive temperature difference between branches and large temperature fluctuations at the material mixing point of the outlet main pipe 130, which would affect product quality.

[0090] The control method for the multi-branch parallel evaporative cooling system in this embodiment also includes:

[0091] S12. The flow rate of multiple cooling branches 120 is set according to the piping structure of the evaporative cooling system. The first variable frequency fan is positioned on the cooling branch 120 with the highest flow rate deviation. Correspondingly, S30 includes: activating the fixed frequency fan and all variable frequency fans except the first variable frequency fan in descending order of the flow rate deviation of the multiple cooling branches 120; and deactivating the fixed frequency fan and all variable frequency fans except the first variable frequency fan in ascending order of the flow rate deviation of the multiple cooling branches 120. This activation sequence helps to quickly improve the cooling effect of the high-flow-rate cooling branches 120, thereby improving the overall operating efficiency of the evaporative cooling system.

[0092] Furthermore, in this embodiment, the variable frequency fan on the cooling branch 120 with the smallest distance from the outlet main pipe 130 of the evaporative cooling system is designated as the first variable frequency fan. S30 also includes: starting the industrial frequency fan and the remaining variable frequency fans (excluding the first variable frequency fan) on each cooling branch 120 in ascending order of distance from the fan to the outlet main pipe 130 of the evaporative cooling system; and turning off the industrial frequency fan and the remaining variable frequency fans (excluding the first variable frequency fan) on each cooling branch 120 in descending order of distance from the fan to the outlet main pipe 130 of the evaporative cooling system. Since the material temperature is generally higher the farther away from the outlet main pipe 130, the efficiency of air cooling through contact with air is higher, which can make full use of natural air cooling and reduce operating energy consumption; the material temperature is generally lower the closer to the outlet main pipe 130, the efficiency of air cooling through contact with air is lower, and the overall cooling effect of adding air cooling is significantly improved. Therefore, this starting sequence makes full use of the combination of air cooling and evaporative cooling, reducing the energy consumption of the evaporative cooling system.

[0093] Therefore, as Figure 4 As shown, a specific operation flow of this embodiment is as follows:

[0094] The target temperature T0 is set to 50℃, and the second temperature sensor TT02 detects a real-time temperature T1 of 55℃, at which point the regulating unit 400 starts.

[0095] First, based on the flow rate and the distance of 130 from the outlet main pipe, the first variable frequency fan is set as F11. F11 starts at the lowest operating frequency of 20Hz (customizable), and the frequency temperature control logic is in automatic mode. If the real-time temperature T1=54.8℃ is still too high, its frequency will automatically rise to the highest frequency (50Hz, the same below).

[0096] Assuming the real-time temperature T1=54.5℃ is still too high, the first industrial frequency fan F16 will start according to the balance sequence of each branch, the flow rate, and the distance of 130 from the outlet main pipe. At the same time as F16 starts, the program will quickly reduce the frequency of F11 to the minimum operating frequency of 20Hz to cooperate with the newly started industrial frequency fan and prevent too much impact on the system, thus achieving "stepless speed regulation". If the real-time temperature T1=54.3℃ is still too high, the frequency of F11 will automatically rise to the maximum frequency again.

[0097] Assuming that the real-time temperature T1=54℃ of the material outlet main pipe is still too high, the second industrial frequency fan F08 will start according to the balance sequence of each branch, the flow rate, and the distance of 130 from the outlet main pipe. At the same time as F08 starts, the program will quickly reduce the frequency of F11 to the minimum operating frequency of 20Hz. If the real-time temperature T1=53.7℃ is still too high, the frequency of F11 will automatically rise to the maximum frequency again.

[0098] This process continues until all the main frequency fans have started. Assuming that the real-time temperature T1=52℃ of the material outlet main pipe is still too high, the second variable frequency fan F15 will start based on the flow rate and the distance of 130 from the outlet main pipe. The second variable frequency fan F15 will start at the lowest operating frequency of 20Hz, and its frequency control temperature logic will be in automatic mode. The first variable frequency fan F11 will switch to 50Hz fixed frequency operation. If the real-time temperature T1=51.9℃ is still too high, the frequency of F15 will automatically increase to the highest frequency.

[0099] Assuming that the real-time temperature T1=51.5℃ of the material outlet main pipe is still too high, the third variable frequency fan F07 will start according to the balance sequence of each branch, the flow rate, and the distance of 130 from the outlet main pipe. The third variable frequency fan F07 will start at the lowest operating frequency of 20Hz, and the frequency control temperature logic will be in automatic mode. The second variable frequency fan F15 will switch to 50Hz fixed frequency operation. If the real-time temperature T1=51.2℃ is still too high, the frequency of F07 will automatically rise to the highest frequency.

[0100] This process continues until the real-time temperature T1 = 50℃. Assuming all variable frequency fans have started and reached a frequency of 50Hz, if the real-time temperature T1 = 50.2℃ is still too high, it indicates that the evaporative cooler is operating at full load. The regulating unit 400 can further control the temperature through other adjustment methods. In this embodiment, the specific start-up sequence of the fans is as follows: Figure 4 As shown in the image.

[0101] Another specific operating procedure in this embodiment is as follows:

[0102] The target temperature T0 is set to 55℃, and the second temperature sensor TT02 detects a real-time temperature T1 of 50℃, at which point the regulating unit 400 starts.

[0103] First, based on the flow rate and the distance from the outlet main pipe 130, the first variable frequency fan is set as F11. Among the other variable frequency fans, based on the balance sequence of each branch, the flow rate, and the distance from the outlet main pipe 130, the frequency of F21 is automatically reduced to the minimum operating frequency of 20Hz.

[0104] Assuming that the real-time temperature T1=50.5℃ is still too low, F21 will be shut off. Based on the balance sequence of each branch, the flow rate, and the distance from the outlet main pipe 130, the frequency of F01 will automatically decrease to the minimum operating frequency.

[0105] This continues until only the first variable frequency fan F11 is running and has been reduced to the lowest operating frequency of 20Hz. Assuming that the real-time temperature T1=53.5℃ of the material outlet manifold is still too low, the industrial frequency fan F10 will stop based on the flow rate and the distance of 130 from the outlet manifold. At the same time as F10 stops, the program will quickly increase the frequency of F11 to the highest operating frequency of 50Hz. If the real-time temperature T1=53.7℃ is still too low, the frequency of F11 will automatically drop to the lowest operating frequency.

[0106] Assuming that the real-time temperature T1=53.9℃ of the material outlet main pipe is still too low, then according to the balance sequence of each branch, the flow rate, and the distance of 130 from the outlet main pipe, the industrial frequency fan F22 will be stopped. At the same time as F22 stops, the program will quickly increase the frequency of F11 to the maximum operating frequency of 50Hz. If the real-time temperature T1=53.9℃ is still too low, then the frequency of F11 will automatically drop to the minimum operating frequency.

[0107] This continues until the real-time temperature T1=55℃. If the real-time temperature T1=54.7℃ is still too low when all the power frequency fans are turned off, then the F11 frequency will automatically drop to the minimum operating frequency. If the real-time temperature T1=54.8℃ is still too low at this time, then F11 will be turned off.

[0108] Assuming that the real-time temperature T1=54.9℃ is still too low until all fans are turned off, the regulating unit 400 can further control the temperature through other adjustment methods.

[0109] In summary, in this embodiment, the control method for a multi-branch parallel evaporative cooling system controls the temperature of the main outlet pipe of the evaporative cooling system, unifies the control of the fans in different cooling branches 120 throughout the system, sets a first variable frequency fan, and limits the start-up and shutdown sequence of the fixed frequency fan and the variable frequency fan. This achieves a reduction in the overall energy consumption of the evaporative cooling system and stable temperature regulation, solving the problem of low automation in the single-loop control scheme of the existing evaporative cooling system, which is also very detrimental to the stable operation of the system. In addition, for operators, this embodiment only requires the operator to set the target temperature T0 and start the system, and the system can automatically perform efficient temperature control, thereby reducing the difficulty of operation and saving labor costs.

[0110] In another scenario, when the multi-branch parallel evaporative cooling system provided in Example 1 is under maintenance for multiple fans, one operational flow of the control method for the multi-branch parallel evaporative cooling system in this embodiment is as follows:

[0111] like Figure 5 As shown, the F01, F11, F18, and F23 fans are shut down for maintenance. The target temperature T0 is set to 50℃, and the second temperature sensor TT02 detects a real-time temperature T1 of 55℃. The regulating unit 400 then starts.

[0112] First, based on the flow deflection and the distance from the outlet main pipe 130, since the flow deflection of cooling branch 120 where F15 is located is the same as that of cooling branch 120 where F11 is located, and F15 is the closest to the outlet main pipe 130 among the two cooling branches 120 with the same flow deflection, the first variable frequency fan is set to F15. F15 starts at the lowest operating frequency of 20Hz (customizable), and the frequency temperature control logic is in automatic mode. If the real-time temperature T1=54.8℃ is still too high, its frequency will automatically increase to the highest frequency (50Hz, the same below).

[0113] Assuming the real-time temperature T1=54.5℃ is still too high, the first industrial frequency fan F12 will start according to the balance sequence of each branch, the flow rate, and the distance of 130 from the outlet main pipe. At the same time as F12 starts, the program will quickly reduce the frequency of F15 to the minimum operating frequency of 20Hz to cooperate with the newly started industrial frequency fan and prevent too much impact on the system, thus achieving "stepless speed regulation". If the real-time temperature T1=54.3℃ is still too high, the frequency of F15 will automatically rise to the maximum frequency again.

[0114] Assuming that the real-time temperature T1=54℃ of the material outlet main pipe is still too high, the second industrial frequency fan F08 will start according to the balance sequence of each branch, the flow rate, and the distance of 130 from the outlet main pipe. At the same time as F08 starts, the program will quickly reduce the frequency of F15 to the minimum operating frequency of 20Hz. If the real-time temperature T1=53.7℃ is still too high, the frequency of F15 will automatically rise to the maximum frequency again.

[0115] Following this pattern, skip F18 until all the mains frequency fans have started. Assuming that the real-time temperature T1=52℃ of the material outlet main pipe is still too high, the second variable frequency fan F07 starts based on the flow rate and the distance of 130 from the outlet main pipe. The second variable frequency fan F07 starts at the lowest operating frequency of 20Hz, and its frequency temperature control logic is in automatic mode. The first variable frequency fan F15 then switches to 50Hz fixed frequency operation. If the real-time temperature T1=51.9℃ is still too high, the frequency of the second variable frequency fan F07 automatically increases to the highest frequency.

[0116] Assuming that the real-time temperature T1=51.5℃ of the material outlet main pipe is still too high, the third variable frequency fan F19 will start according to the balance sequence of each branch, the flow rate, and the distance of 130 from the outlet main pipe. The third variable frequency fan F19 will start at the lowest operating frequency of 20Hz, and the frequency control temperature logic will be in automatic mode. The second variable frequency fan F07 will switch to 50Hz fixed frequency operation. If the real-time temperature T1=51.2℃ is still too high, the frequency of the third variable frequency fan F19 will automatically increase to the highest frequency.

[0117] Following this pattern, skip F01 and F23 until the real-time temperature T1 = 50℃. Assuming all variable frequency fans have started and reached a frequency of 50Hz, if the real-time temperature T1 = 50.2℃ is still too high, it indicates that the evaporative air cooler is already operating at full load. The regulating unit 400 can further control the temperature through other adjustment methods. Adjustments can be made in reverse order during the heating process.

[0118] Therefore, the control method of the multi-branch parallel evaporative cooling system in this embodiment can also adapt to different fan operating conditions, automatically adjust the fan operating sequence, and maintain the energy saving and system stability of the evaporative cooling system.

[0119] Example 3

[0120] This embodiment provides a variation of Embodiment 2, the main difference being that it employs a different multi-branch parallel evaporative cooling system. Please refer to [link to related documentation]. Figure 6 In embodiment 3, the detection unit 300 of the evaporative cooling system also includes 6 flow sensors TS01a~TS01f. The 6 flow sensors TS01a~TS01f are respectively installed at the outlets of the 6 cooling branches 120, which can detect the flow rate at the outlets of multiple cooling branches 120. This is used to replace the scheme of setting the flow rate deviation, and the operating sequence of the fans on different cooling branches 120 can be set directly by detecting the flow rate.

[0121] Compared with Example 2, this example does not include the relevant steps in S12 and S30. The control method of the multi-branch parallel evaporative cooling system in this example also includes the following steps:

[0122] S22. The flow rate at the outlet of multiple cooling branches of the evaporative cooling system is monitored in real time by six flow sensors TS01a~TS01f.

[0123] Furthermore, the first variable frequency fan is positioned on the cooling branch 120 with the highest outlet flow rate. Correspondingly, S30 includes: starting the fixed frequency fan and all other variable frequency fans except the first variable frequency fan in descending order of outlet flow rate of the multiple cooling branches 120; and stopping the fixed frequency fan and all other variable frequency fans except the first variable frequency fan in ascending order of outlet flow rate of the multiple cooling branches 120. This starting sequence helps to quickly improve the cooling effect of the high-flow cooling branch 120, thereby improving the overall working efficiency of the evaporative cooling system.

[0124] In this embodiment, the control method of the multi-branch parallel evaporative cooling system can directly adapt to different cooling branch 120 pipeline layouts by real-time detection of the outlet flow of multiple cooling branches 120 of the evaporative cooling system, without the need to reset the flow deviation. Compared with embodiment 2, it has advantages in terms of ease of operation and system adaptability.

[0125] Example 4

[0126] This embodiment provides a variation of Embodiment 2. The main difference from Embodiment 2 is that a different multi-branch parallel evaporative cooling system is used. In Embodiment 4, the detection unit 300 of the evaporative cooling system further includes 24 third temperature sensors (not shown in the figure), which are set at the corresponding positions of each fan in the cooling branch 120 of the evaporative cooling system. These sensors can detect the temperature T2 at the corresponding position of each fan in the cooling branch 120 of the evaporative cooling system. This replaces the scheme in S30 that determines the starting sequence based on the distance from the fan to the outlet main pipe 130 of the evaporative cooling system. Instead, the operating sequence of different fans on each cooling branch 120 is set directly by detecting the temperature at the corresponding position of each fan in the cooling branch 120.

[0127] Compared with Embodiment 2, S30 in this embodiment does not include steps related to the distance from the fan to the outlet main pipe 130 of the evaporative cooling system. The control method of the multi-branch parallel evaporative cooling system in this embodiment also includes the following steps:

[0128] S24. The temperature T2 at the corresponding point on the cooling branch 120 of each fan in the evaporative cooling system is detected in real time by 24 third temperature sensors.

[0129] Furthermore, the variable frequency fan with the smallest difference between the corresponding temperature T2 on the cooling branch 120 and the real-time temperature T1 of the outlet main pipe 130 is designated as the first variable frequency fan. Correspondingly, S30 includes: starting the industrial frequency fan on each cooling branch 120 in ascending order of the difference between the corresponding temperature T2 and the real-time temperature T1 of the outlet main pipe 130, and the other variable frequency fans except the first variable frequency fan; and shutting down the industrial frequency fan on each cooling branch 120 in descending order of the difference between the corresponding temperature T2 and the real-time temperature T1 of the outlet main pipe 130.

[0130] In this embodiment, the control method of the multi-branch parallel evaporative cooling system can replace the scheme of directly determining the opening sequence by the distance between the fan and the outlet main pipe 130 by real-time detection of the temperature T2 of each fan of the evaporative cooling system at the corresponding point on the cooling branch 120. At the same time, it can also detect the temperature difference between local areas on the cooling branch 120, which helps to discover local anomalies in the system. Compared with embodiment 2, it has advantages in terms of safety and stability.

[0131] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A control method for a multi-branch parallel evaporative cooling system, characterized in that, An evaporative cooling system comprising multiple parallel cooling branches (120), wherein each cooling branch (120) is equipped with multiple fans, including both fixed-frequency fans and variable-frequency fans, is used. The control method for the parallel evaporative cooling system comprises the following steps: S10. Set the target temperature T0 of the outlet manifold (130) of the evaporative cooling system; S20. Real-time monitoring of the real-time temperature T1 of the outlet manifold (130) of the evaporative cooling system; S30. The real-time temperature T1 is controlled by adjusting the total operating frequency of the fan to make it approach the target temperature T0; Wherein, S30 includes: Set the first variable frequency fan; When the real-time temperature T1 is greater than the target temperature T0, the first variable frequency fan, the power frequency fan, and the other variable frequency fans except the first variable frequency fan are started sequentially until the real-time temperature T1 equals the target temperature T0 or the total operating frequency of the fans reaches its maximum value; when the real-time temperature T1 is less than the target temperature T0, the other variable frequency fans except the first variable frequency fan, the power frequency fan, and the first variable frequency fan are turned off sequentially until the real-time temperature T1 equals the target temperature T0 or all the fans are turned off. When the fixed frequency fan starts, the first variable frequency fan quickly drops to the minimum operating frequency; when the fixed frequency fan stops, the first variable frequency fan quickly rises to the maximum operating frequency; and all variable frequency fans start at the minimum operating frequency.

2. The control method for a multi-branch parallel evaporative cooling system as described in claim 1, characterized in that, S30 includes: starting the next fan after all the operating variable frequency fans have reached their maximum operating frequency; and shutting down the operating fans after they have reached their minimum operating frequency.

3. The control method for a multi-branch parallel evaporative cooling system as described in claim 1, characterized in that, S30 includes: starting the power frequency fan and the remaining variable frequency fans except the first variable frequency fan, according to the order of the number of fans started in the multiple cooling branches (120) from few to many.

4. The control method for a multi-branch parallel evaporative cooling system as described in claim 1, characterized in that, It also includes the following steps: S12. Set the deflection degree of multiple cooling branches (120) according to the piping structure of the evaporative cooling system; Furthermore, the first variable frequency fan is positioned on the cooling branch (120) with the largest flow deviation, and S30 includes: According to the order of the deflection of the multiple cooling branches (120) from large to small, turn on the mains frequency fan and the other variable frequency fans except the first variable frequency fan; according to the order of the deflection of the multiple cooling branches (120) from small to large, turn off the mains frequency fan and the other variable frequency fans except the first variable frequency fan.

5. The control method for a multi-branch parallel evaporative cooling system as described in claim 1, characterized in that, It also includes the following steps: S22. Real-time monitoring of the outlet flow rates of multiple cooling branches (120) of the evaporative cooling system; Furthermore, the first variable frequency fan is positioned on the cooling branch (120) with the largest outlet flow rate, and S30 includes: According to the order of the outlet flow of the multiple cooling branches (120) from large to small, start the mains frequency fan and the other variable frequency fans except the first variable frequency fan; According to the order of the outlet flow of the multiple cooling branches (120) from small to large, shut down the mains frequency fan and the other variable frequency fans except the first variable frequency fan.

6. The control method for a multi-branch parallel evaporative cooling system as described in claim 1, characterized in that, The variable frequency fan with the smallest distance from the outlet main pipe (130) on the cooling branch (120) is designated as the first variable frequency fan, and S30 includes: On each of the cooling branch lines (120), the power frequency fan and the other variable frequency fans except the first variable frequency fan are turned on in order of increasing distance between the fan and the outlet main pipe (130); On each of the cooling branch lines (120), the power frequency fan and the other variable frequency fans except the first variable frequency fan are shut down in descending order of the distance between the fan and the outlet main pipe (130).

7. The control method for a multi-branch parallel evaporative cooling system as described in claim 1, characterized in that, It also includes the following steps: S24. Real-time detection of the temperature T2 at the corresponding point of each fan on the cooling branch (120); Furthermore, the variable frequency fan with the smallest difference between the corresponding temperature T2 and the real-time temperature T1 is designated as the first variable frequency fan, and S30 includes: On each of the cooling branches (120), the industrial frequency fan and the other variable frequency fans except the first variable frequency fan are turned on in ascending order of the difference between the corresponding temperature T2 and the real-time temperature T1. On each of the cooling branches (120), the mains frequency fan and the other variable frequency fans except the first variable frequency fan are turned off in descending order of the difference between the corresponding temperature T2 and the real-time temperature T1.

8. A multi-branch parallel evaporative cooling system, characterized in that, Include: The working unit (100) has multiple parallel cooling branches (120), each cooling branch (120) is equipped with an evaporative cooling water tank, multiple spray water pumps and multiple fans, the multiple fans including power frequency fans and variable frequency fans; The setting unit (200) can set the target temperature T0 of the outlet manifold (130) of the working unit (100); The detection unit (300) includes a second temperature sensor disposed on the outlet manifold (130) of the working unit (100), which can detect the real-time temperature T1 of the outlet manifold (130) of the working unit (100) in real time; The adjustment unit (400) is electrically connected to the working unit (100), the setting unit (200) and the detection unit (300), and can adjust the total working frequency of the fan to control the real-time temperature T1 so that it approaches the target temperature T0, and can set the first variable frequency fan; When the real-time temperature T1 is greater than the target temperature T0, the adjustment unit (400) can sequentially start the first variable frequency fan, the power frequency fan, and the other variable frequency fans except the first variable frequency fan; until the real-time temperature T1 is equal to the target temperature T0 or the total operating frequency of the fans reaches the maximum value. When the real-time temperature T1 is less than the target temperature T0, the regulating unit (400) can sequentially shut down the other variable frequency fans except the first variable frequency fan, the power frequency fan, and the first variable frequency fan; until the real-time temperature T1 is equal to the target temperature T0 or all fans are shut down; When the fixed frequency fan starts, the first variable frequency fan quickly drops to the minimum operating frequency; when the fixed frequency fan stops, the first variable frequency fan quickly rises to the maximum operating frequency; and all variable frequency fans start at the minimum operating frequency.

9. The multi-branch parallel evaporative cooling system as described in claim 8, characterized in that, The detection unit (300) further includes: Multiple third temperature sensors are installed at corresponding locations on the cooling branch (120) of each fan in the evaporative cooling system, and can detect the temperature at the corresponding locations on the cooling branch (120) of each fan in the evaporative cooling system; and Multiple flow sensors are installed at the outlets of multiple cooling branches (120) to detect the flow rate at the outlets of multiple cooling branches (120).

Images