Indirect air-cooling anti-freezing roller shutter and louver combined regulation control method

Abstract

The application provides a combined regulation and control method of indirect air cooling anti-freezing roller shutter and louver, and belongs to the technical field of energy saving of indirect air cooling system of thermal power generating unit. The method comprises the following steps: confirming the temperature field distribution law of the indirect air cooling system, the control parameters of the louver and the blocking back pressure value of the normal operation load interval of the indirect air cooling unit; confirming the anti-freezing typical low-temperature cooling triangle corresponding to the winter dominant wind direction in the cooling triangle; establishing the control strategy of the indirect air cooling system under the non-winter operation condition, and establishing the control strategy of the indirect air cooling system under the winter operation condition.

Description

Technical Field

[0001] This invention relates to the field of energy-saving technology for indirect air-cooled systems of thermal power generating units, specifically to a combined adjustment and control method for indirect air-cooled antifreeze roller blinds and louvers, a computer-readable storage medium, and an electronic device. Background Technology

[0002] Indirect air-cooled units, using water as the cooling medium, have a design back pressure at least 1-2 kPa lower than direct air-cooled units, and an even lower back pressure during summer operation. Theoretically, they should be more economical than direct air-cooled units. However, comparisons of operating conditions and related data from air-cooled units commissioned worldwide in the early 1990s show that the economic advantage of indirect air-cooled units is not significant. This trend is also evident in the energy consumption data analysis of domestic thermal power units in recent years. Under similar regional and meteorological conditions, and with similar utilization hours, indirect air-cooled units do not demonstrate superior economic performance compared to direct air-cooled units.

[0003] Research and preliminary studies have revealed that one of the main reasons for this situation is the lack of effective means to control the operation of indirect air-cooled systems. Currently, the indirect air-cooled systems in my country's thermal power units generally use SCAL-type vertically arranged cooling radiators. A 660MW unit typically consists of 170-180 cooling triangles, divided into about 10 sectors. Conventional louvers are usually manually controlled by operators based on experience; adjusting the louver opening controls the airflow entering the cooling triangles, thereby controlling the temperature of the circulating water return header.

[0004] Another type of anti-freezing roller shutter device for indirect air-cooled towers exists. The anti-freezing unit includes a support frame, anti-suction net, guide rail, roller shutter, roller shutter box, anti-fall cable, and anti-fall cable reel. The anti-fall cable reel is connected to the output shaft of the roller shutter motor. The louvers and anti-freezing roller shutter can be used together to control the temperature and back pressure of the indirect air-cooled tower, achieving both safety and economy for the air-cooled unit. However, currently, there is no method for combined control and adjustment of the louvers and anti-freezing roller shutter. Summary of the Invention

[0005] The purpose of this invention is to provide a method for joint adjustment and control of indirect air-cooled antifreeze roller blinds and louvers, a computer-readable storage medium, and an electronic device, so as to achieve joint control and adjustment of louvers and antifreeze roller blinds for different heat exchange processes in each cooling triangle under different ambient temperature conditions.

[0006] To achieve the above objectives, the first aspect of the present invention provides a method for the combined adjustment and control of an indirect air-cooled antifreeze roller blind and a venetian blind, comprising:

[0007] Confirm the temperature field distribution pattern of the indirect air-cooled system, the control parameters of the louvers, and the blocking back pressure value in the normal operating load range of the indirect air-cooled unit;

[0008] In the cooling triangle, identify the typical low-temperature cooling triangle for antifreeze protection corresponding to the prevailing winter wind direction;

[0009] Based on the temperature field distribution law, the control parameters of the louvers, the blocking back pressure value, and the typical low-temperature cooling triangle for antifreeze, a control strategy for the indirect air-cooling system under non-winter operating conditions is established, as well as a control strategy for the indirect air-cooling system under winter operating conditions is established.

[0010] Optionally, the process of confirming the temperature field distribution law of the indirect air-cooling system includes:

[0011] Numerical simulation calculations of the temperature field of the indirect air-cooled system were carried out to confirm the temperature field distribution law of the indirect air-cooled system under different loads and environmental conditions.

[0012] Optionally, the process for confirming the control parameters of the venetian blinds includes:

[0013] Numerical simulation analysis of the temperature field under the prevailing winter wind was conducted to obtain the control parameters of the louvers under different operating conditions of the indirect air-cooling system.

[0014] Optionally, the process for confirming the blocking back pressure value in the normal operating load range of the indirect air-cooled unit includes:

[0015] Conduct tests on the blocking back pressure under normal operating conditions of the indirect air-cooled unit to determine the blocking back pressure value in the normal operating load range of the indirect air-cooled unit.

[0016] Optionally, the confirmation process for the typical low-temperature cooling triangle for antifreeze includes:

[0017] Conduct temperature field simulation calculations for indirect air-cooled islands;

[0018] By comparing the simulation results with the field data, and based on the comparison results, the typical low-temperature cooling triangle for antifreeze corresponding to the prevailing winter wind direction is identified in the cooling triangle.

[0019] Optionally, the control strategy for establishing the indirect air-cooling system under non-winter operating conditions includes:

[0020] The temperature threshold of the ambient temperature was determined based on the temperature field distribution law of the indirect air cooling system.

[0021] The lower limit threshold of the venetian blind opening is determined based on the control parameters of the venetian blind;

[0022] When the ambient temperature is below the temperature threshold, adjust the opening of the louvers to below the lower limit threshold.

[0023] When the number of louvers adjusted to below the lower limit threshold reaches the set threshold, all the antifreeze roller shutters of the cooling triangle are opened to ensure that the back pressure value of the indirect air-cooled unit is maintained within the economic operating range.

[0024] Optionally, the control strategy for establishing the indirect air-cooling system under winter operating conditions includes:

[0025] When more than half of the louvers of the typical low-temperature cooling triangle for antifreeze reach the lower limit threshold, close the antifreeze roller shutters of some of the typical low-temperature cooling triangles to the preset threshold.

[0026] When the louver opening of all cooling triangles drops to the lower limit threshold, and the outlet water temperature of the sector formed by all cooling triangles is still lower than the corresponding circulating water temperature of the indirect air-cooled unit operating within the safe range of the blocking back pressure value, close the antifreeze roller shutters of all cooling triangles to the preset threshold.

[0027] Optionally, a long short-term memory neural network algorithm is used, with the opening degree of the louvers, ambient temperature, inlet wind speed of the sector, and outlet water temperature of the sector as inputs, and control commands as outputs, to realize the opening and closing of the antifreeze roller shutter of the typical low-temperature cooling triangle.

[0028] A second aspect of the present invention provides a computer-readable storage medium storing computer instructions that, when executed on a computer, cause the computer to perform the method described in the first aspect.

[0029] A third aspect of the present invention provides an electronic device, comprising: at least one processor and a memory;

[0030] The memory stores computer execution instructions;

[0031] The at least one processor executes computer execution instructions stored in the memory, causing the electronic device to perform the method described in the first aspect.

[0032] The beneficial effects of this invention are as follows:

[0033] (1) It meets the precise antifreeze function of the circulating water system of the indirect air-cooled system;

[0034] (2) Achieve energy-saving control of the indirect air-cooled system for surface condensers;

[0035] (3) Improved the stability and safety of the indirect air-cooled circulating water control system.

[0036] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0037] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0038] Figure 1 This is a flowchart of a combined adjustment and control method for an indirect air-cooled antifreeze roller blind and venetian blinds provided in one embodiment of the present invention. Detailed Implementation

[0039] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0040] Example 1

[0041] Figure 1 This is a flowchart of a combined adjustment and control method for an indirect air-cooled antifreeze roller blind and venetian blind provided in Embodiment 1 of the present invention. Figure 1 As shown, Embodiment 1 of the present invention provides a method for the combined adjustment and control of an indirect air-cooled anti-freeze roller blind and a venetian blind, the method comprising:

[0042] S1: Confirm the temperature field distribution pattern of the indirect air-cooled system.

[0043] Specifically, in this embodiment, the temperature field distribution law of the indirect air-cooled system under different loads and environmental conditions is confirmed by conducting numerical simulation calculations of the temperature field of the indirect air-cooled system.

[0044] Based on the confirmed temperature field distribution pattern, the temperature point distribution in the indirect air-cooling system can be determined. After determining the temperature distribution in the indirect air-cooling system, the temperature threshold at each location can be determined accordingly.

[0045] It should be noted that the temperature field described in this embodiment refers to the collection of temperatures at various points within the material system. It is a function of time and spatial coordinates, reflecting the spatial and temporal distribution of temperature.

[0046] It is understandable that the numerical simulation calculation of the temperature field of the indirect air-cooled system in this embodiment can be achieved using thermal simulation software such as ANSYS.

[0047] S2: Confirm the optimal control parameters for the venetian blinds.

[0048] Specifically, in this embodiment, the optimal control parameters of the louvers under different steady-state conditions are obtained by conducting numerical simulation analysis of the temperature field under the prevailing winter wind.

[0049] It is understood that the control parameters mentioned here are mainly the opening degree of the louvers. Generally, each louver corresponds to a cooling triangle, and every two louvers share a set of actuators. As an actuator of the indirect system, the louvers can change the amount of cooling air entering the cooling triangle by changing the opening degree of the louvers, thereby changing the heat exchange status of the cooling triangle and the outlet water temperature.

[0050] After the water from each cooling triangle is collected, it mixes in the sector, and then mixes again before entering the condenser inlet to exchange heat with the turbine exhaust steam. The outlet water temperature of each sector affects the inlet cooling water temperature of the circulating water condenser, which in turn affects the turbine vacuum. Therefore, the turbine vacuum, the outlet water temperature of the sector and the cooling triangle, and the wall temperature are all related to the opening degree control of the louvers.

[0051] S3: Confirm the typical low-temperature cooling triangle for antifreeze in the cooling triangle.

[0052] Specifically, in this embodiment, numerical simulation calculations of the actual temperature field are carried out on site. The simulation calculation results are compared with the on-site data to determine the typical low-temperature cooling triangle for antifreeze under the prevailing winter wind direction.

[0053] It should be noted that the typical low-temperature cooling triangle for freeze protection described in this embodiment refers to the cooling triangle that is prone to low temperatures under winter operating conditions. The number of typical low-temperature cooling triangles for freeze protection should account for 20%-30% of the total number of cooling triangles.

[0054] S4: Determine the blocking back pressure value in the normal operating load range of the indirect air-cooled unit.

[0055] Specifically, in this embodiment, by conducting a test on the blocking back pressure of a normal indirect air-cooled system under normal operating conditions, the blocking back pressure data of the indirect air-cooled unit in the normal operating load range is determined, which facilitates guidance on the economical operation of the indirect air-cooled unit.

[0056] It should be noted that there is no explicit order of execution between steps S1, S2, S3, and S4; the order is only for ease of description in this embodiment.

[0057] S5: Establish control strategies for indirect air-cooled systems under different operating conditions.

[0058] Specifically, in this implementation, the main focus is on establishing control strategies for the indirect air-cooling system under both non-winter and winter operating conditions.

[0059] It is understood that the winter operating condition referred to in this embodiment refers to the operating condition where the ambient temperature at the location of the indirect air-cooled system is below 2°C, and the non-winter operating condition is the opposite of the winter operating condition.

[0060] It should be noted that the 2℃ temperature threshold mentioned here is determined based on the geographical location and meteorological environment of the indirect air-cooling system. The temperature threshold for industrial control will change under different geographical locations and meteorological conditions.

[0061] When the indirect air-cooled system is running outside of winter, the antifreeze roller shutters of the cooling triangle are fully open. Therefore, the main method to achieve the goal of economical operation of the turbine under low back pressure is to control the opening degree of the louvers to obtain a lower sector outlet water temperature.

[0062] The control strategy for the indirect air-cooled system under non-winter operating conditions is as follows:

[0063] First, the ambient temperature threshold is determined based on the temperature field distribution law of the indirect air-cooling system; then, the opening degree threshold of the louvers is determined based on the optimal control parameters of the louvers.

[0064] Secondly, when the ambient temperature is lower than the temperature threshold, adjust the opening of the louvers to below the opening threshold; when the number of louvers with the opening adjusted to below the opening threshold reaches the set threshold, adjust the opening of the antifreeze roller shutter of the typical low-temperature cooling triangle and ensure that the back pressure of the indirect air-cooled unit is maintained within the economic operating range.

[0065] By incorporating the antifreeze roller shutters of the typical low-temperature cooling triangle into the regulation, and by precisely adjusting the opening of the louvers, the back pressure of the condenser can be ensured to operate within the economical operating range. Specifically, the lower the back pressure, the higher the condenser efficiency and the greater the economic efficiency. Different units have different corresponding economical back pressure operating ranges, which can be determined based on the unit's historical data, and will not be elaborated further here.

[0066] The following example illustrates the control strategy of an indirect air-cooled system under non-winter operating conditions:

[0067] When the ambient temperature is low (above 2℃), adjust the louver opening to below 10%. Since there will be problems such as poor adjustment characteristics when the louver opening is below 10%, when the number of louvers with an opening of below 10% reaches one-third of the total number of louvers, close the antifreeze roller shutter of the typical low temperature cooling triangle to a certain extent. The specific degree of closure is determined through on-site testing.

[0068] In indirect air-cooled systems, the louvers are often at a small opening during winter operation, resulting in poor linearity and affecting system safety and stability. To address this issue, during winter operation, in addition to controlling the louver adjustment, a frost-resistant roller shutter control based on a typical low-temperature cooling triangle is added for combined control and adjustment.

[0069] The control strategy for the indirect air-cooled system under winter operating conditions is as follows:

[0070] When the louver opening drops to the lower limit threshold and the sector outlet water temperature is still too low, close the antifreeze roller shutter of the typical low-temperature cooling triangle to a certain degree to reduce the amount of air entering and thus increase the sector outlet water temperature.

[0071] When more than half of the louvers of the typical low-temperature cooling triangle for antifreeze reach the lower limit threshold, close the antifreeze roller shutters of some of the typical low-temperature cooling triangles to the preset threshold.

[0072] When the louver opening of all cooling triangles drops to the lower limit threshold, and the outlet water temperature of the sector is still lower than the circulating water temperature corresponding to the operation of the indirect air-cooled unit within the safe range of the blocking back pressure value, close the antifreeze roller shutters of all cooling triangles to the preset threshold.

[0073] It is understood that the sector described in this embodiment is composed of all cooling triangles. For example, a 660MW unit is generally composed of 170 to 180 cooling triangles, which are divided into about 10 sectors.

[0074] This allows for adjustment of the outlet water temperature while avoiding the non-linear adjustment range of the louvers.

[0075] It is understandable that the lower limit threshold for louver opening mentioned here is the same value as the lower limit threshold for louver opening under non-winter operating conditions, namely 10%. This is because the louver has better linearity when the opening is above 10%, so this is used as the lower limit threshold for opening.

[0076] The following example illustrates the control strategy for an indirect air-cooled system under winter operating conditions:

[0077] When the louvers of a typical low-temperature cooling triangle are opened to more than 1 / 2 of their lower limit of 10%, the antifreeze roller shutters of the typical low-temperature cooling triangle should be closed. The specific number of shutters to be closed can be determined according to the actual situation, such as closing half or one-third, etc.

[0078] When the louver opening of all cooling triangles decreases by 10% and the sector outlet water temperature is still lower than the corresponding circulating water temperature of the indirect air-cooled unit operating within the safe range of blockage back pressure, close the antifreeze roller shutters of all cooling triangles to 3 / 4 or 1 / 2 opening, thereby reducing the amount of air entering and thus increasing the water temperature at the sector outlet.

[0079] In some feasible embodiments, a long short-term memory (LSTM) neural network algorithm is used to implement the antifreeze roller shutter adjustment control of the cooling triangle.

[0080] Specifically, the LSTM is obtained by using parameters such as louver opening, ambient temperature, inlet wind speed, and sector outlet water temperature as inputs and triangular anti-freeze roller shutter control commands as model outputs.

[0081] It is understood that the antifreeze roller shutter structure of the cooling triangle (including the typical low-temperature antifreeze cooling triangle) described in this embodiment includes:

[0082] The system includes a support frame, an anti-suction net, guide rails, a roller blind, a roller blind box, an anti-fall cable, and an anti-fall cable reel. The anti-fall cable reel is sleeved on the output shaft of the roller blind motor, and the upper end of the anti-fall cable is fixed to the upper crossbeam of the support frame. The roller blind box contains a roller blind motor, a roller blind shaft, and a winding reel. The output shaft of the roller blind motor is driven and connected to one end of the roller blind shaft. The other end of the roller blind shaft is driven and connected to the winding reel shaft. The upper end of the roller blind extends out of the roller blind box and is fixed by the upper crossbeam. Two outwardly extending pulleys are provided on both sides of the roller blind box. The roller blind box moves up and down along the guide rails by means of the pulleys embedded in the guide rails on both sides. A roller blind opening feedback device is installed in the guide rails for easy adjustment and control.

[0083] The method described in this embodiment, which uses louvers as the basic adjustment and is combined with cooling triangular antifreeze roller shutters for control, reduces the number of low-temperature triangular shutters on the radiator and avoids the non-linear adjustment range of the louvers. This allows for better adjustment characteristics of the louvers, making it more conducive to obtaining a lower circulating water temperature while meeting antifreeze requirements, thus improving energy-saving performance.

[0084] Example 2

[0085] This embodiment provides a computer-readable storage medium storing computer instructions. When the computer instructions are executed on a computer, the computer performs a combined adjustment and control method for an indirect air-cooled anti-freeze roller blind and venetian blind provided in Embodiment 1.

[0086] Example 3

[0087] This embodiment provides an electronic device, including: at least one processor and a memory;

[0088] The memory stores computer execution instructions;

[0089] The at least one processor executes computer execution instructions stored in the memory, causing the electronic device to perform a combined adjustment and control method for an indirect air-cooled antifreeze roller blind and venetian blind provided in Embodiment 1.

[0090] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0091] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details described above. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe the various possible combinations.

[0092] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the embodiments of the present invention, they should also be regarded as the content disclosed by the embodiments of the present invention.

Claims

1. A method for combined adjustment and control of an indirect air-cooled anti-freeze roller blind and a venetian blind, applied to an indirect air-cooling system, characterized in that, include: Confirm the temperature field distribution pattern of the indirect air-cooled system, the control parameters of the louvers, and the blocking back pressure value in the normal operating load range of the indirect air-cooled unit; Among all cooling triangles, identify the typical low-temperature cooling triangle for antifreeze protection corresponding to the prevailing winter wind direction. Based on the temperature field distribution law, the control parameters of the louvers, the blocking back pressure value, and the typical low-temperature cooling triangle for antifreeze, a control strategy for the indirect air cooling system under non-winter operating conditions is established, as well as a control strategy for the indirect air cooling system under winter operating conditions is established. The established control strategy for the indirect air-cooling system under non-winter operating conditions includes: The temperature threshold of the ambient temperature was determined based on the temperature field distribution law of the indirect air cooling system. The lower limit threshold of the venetian blind opening is determined based on the control parameters of the venetian blind; When the ambient temperature is below the temperature threshold, adjust the opening of the louvers to below the lower limit threshold. When the number of louvers adjusted to below the lower limit threshold reaches the set threshold, all the anti-freeze roller shutters of the cooling triangle are opened to ensure that the back pressure value of the indirect air-cooled unit is maintained within the economic operating range. The established control strategy for the indirect air-cooling system under winter operating conditions includes: When more than half of the louvers of the typical low-temperature cooling triangle for antifreeze reach the lower limit threshold, close the antifreeze roller shutters of some of the typical low-temperature cooling triangles to the preset threshold. When the louver opening of all cooling triangles drops to the lower limit threshold, and the outlet water temperature of the sector formed by all cooling triangles is still lower than the corresponding circulating water temperature of the indirect air-cooled unit when operating within the safe range of the blocking back pressure value, close the antifreeze roller shutters of all cooling triangles to the preset threshold. The process for confirming the temperature field distribution law of the indirect air-cooling system includes: Numerical simulation calculations of the temperature field of the indirect air-cooled system were carried out to confirm the temperature field distribution law of the indirect air-cooled system under different loads and environmental conditions. The process for confirming the control parameters of the venetian blinds includes: Numerical simulation analysis of the temperature field under the prevailing winter wind was conducted to obtain the control parameters of the louvers under different operating conditions of the indirect air-cooling system.

2. The method for combined adjustment and control of indirect air-cooled anti-freeze roller blind and venetian blind according to claim 1, characterized in that, The process for confirming the blocking back pressure value in the normal operating load range of the indirect air-cooled unit includes: Conduct tests on the blocking back pressure under normal operating conditions of the indirect air-cooled unit to determine the blocking back pressure value in the normal operating load range of the indirect air-cooled unit.

3. The method for combined adjustment and control of indirect air-cooled anti-freeze roller blind and venetian blind according to claim 1, characterized in that, The confirmation process for the typical low-temperature cooling triangle for freeze protection includes: Conduct temperature field simulation calculations for indirect air-cooled islands; By comparing the simulation results with the field data, and based on the comparison results, the typical low-temperature cooling triangle for antifreeze corresponding to the prevailing winter wind direction is identified in the cooling triangle.

4. The method for combined adjustment and control of indirect air-cooled anti-freeze roller blind and venetian blind according to claim 1, characterized in that, Using a long short-term memory neural network algorithm, the opening and closing of the antifreeze roller shutter of the typical low-temperature cooling triangle is realized by taking the opening degree of the louvers, the ambient temperature, the inlet wind speed of the sector and the outlet water temperature of the sector as inputs and the control command as output.

5. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed on a computer, cause the computer to perform the method of any one of claims 1-4.

6. An electronic device, characterized in that, include: At least one processor and memory; The memory stores computer execution instructions; The at least one processor executes computer execution instructions stored in the memory, causing the electronic device to perform the method of any one of claims 1-4.

Images