Backpressure adjusting method and device for natural ventilation direct air cooling system

Abstract

The invention provides a backpressure adjusting method and device for a natural ventilation direct air cooling system, and the method comprises the steps: obtaining the current backpressure of a steam turbine, and executing an up-cut step sequence when the current backpressure is greater than a set backpressure first preset difference value, and the up-cut step sequence comprises the steps: setting a first target sector as a new commissioning sector, and setting a second target sector as a second commissioning sector; the control mode of the shutter opening degree of the new commissioning sector is set to be automatic adjustment within the first preset opening degree range; when the current back pressure is smaller than a second preset difference value of the set back pressure, a down-cut step sequence is executed, and the down-cut step sequence comprises the step that the control mode of the shutter of the second target sector is automatically adjusted in the first preset opening degree range from the second preset opening degree range to the second preset opening degree range till the second target sector quits operation. By controlling the automatic switching of the sectors and the automatic adjustment of the opening degree of the shutter, the automatic adjustment of the back pressure is realized, the automation degree of the back pressure adjustment is improved, the precision and efficiency of the back pressure adjustment are further improved, and the efficiency of the generator set is improved.

Description

Technical Field

[0001] This application relates to the technical field of air-cooling technology for power plants, and in particular to a method and device for adjusting the back pressure of a natural draft direct air-cooling system. Background Art

[0002] The air-cooling system is divided into two major systems: direct air-cooling and indirect air-cooling. The direct air-cooling system is divided into mechanical ventilation and natural draft direct air-cooling system (NDC) due to different ventilation methods. Among them, because the natural draft direct air-cooling system NDC has both economic and environmental benefits and can provide a more sustainable and clean energy solution, it has a wide range of application prospects.

[0003] For the natural draft direct air-cooling system NDC, a natural draft cooling tower is generally set up. Inside the natural draft cooling tower, the exhaust steam of the steam turbine (i.e., the water to be cooled) is sent to the air-cooled condenser through the exhaust steam pipeline. The cold air enters the tower from the bottom of the natural draft cooling tower and cools the exhaust steam in the air-cooled condenser into water. The condensed water is then pumped back to the regenerative system of the steam turbine through the condensate pump, and the heated cold air leaves the cooling tower from the top of the tower.

[0004] At present, for the back pressure adjustment of the natural draft direct air-cooling system NDC, most of the methods used are still the back pressure adjustment methods of the indirect air-cooling system, that is, manual adjustment. However, in the natural draft direct air-cooling system NDC, the exhaust steam of the steam turbine is directly condensed by air, and its back pressure changes with the ambient air temperature. Especially in areas with large temperature differences, the back pressure changes greatly. The manual adjustment method not only has low efficiency, but also has a large adjustment error, affecting the efficiency of the generating unit. Summary of the Invention

[0005] This application provides a method and device for adjusting the back pressure of a natural draft direct air-cooling system to solve the technical problems mentioned in the background art.

[0006] In a first aspect, this application provides a method for adjusting the back pressure of a natural draft direct air-cooling system, including:

[0007] Obtain the current back pressure of the steam turbine;

[0008] When the current back pressure is greater than the set back pressure and the difference is greater than the first preset difference, execute the up-cut step sequence. Among them, if the current working condition is a winter working condition, the up-cut step sequence includes: setting the first target sector as the new operating sector, and setting the control mode of the louver opening degree of the new operating sector to automatically adjust within the first preset opening range. The first target sector is one of the sectors that are not currently in operation;

[0009] When the current back pressure is less than the set back pressure and the difference is greater than the second preset difference, the down-cut step sequence is executed. Among them, if the current working condition is the winter working condition, the down-cut step sequence includes: changing the control mode of the shutter of the second target sector from automatically adjusting within the second preset opening range to automatically adjusting within the first preset opening range until the second target sector is taken out of operation. The second target sector is one of the currently operating sectors, and the lower limit of the second preset opening range is the upper limit of the first preset opening range.

[0010] Optionally, when the first target sector is the sector provided with a steam isolation valve, the up-cut step sequence further includes:

[0011] Opening the condensate isolation valve and the steam isolation valve of the first target sector, and reducing the opening of the shutter of the currently operating sector to the current opening;

[0012] And / or, when the second target sector is the sector provided with a steam isolation valve, the down-cut step sequence further includes:

[0013] Closing the condensate isolation valve and the steam isolation valve of the second target sector.

[0014] Optionally, after obtaining the current back pressure of the steam turbine, it further includes:

[0015] Obtaining a first duration, the current shutter opening, and the condensate temperature of the non-isolated sector. The first duration is the duration between the moment corresponding to the last execution of the step sequence to adjust the back pressure and the current moment;

[0016] The execution of the up-cut step sequence includes:

[0017] When the first duration is greater than the preset duration, the value obtained by subtracting the current shutter opening of the currently operating sector from the upper limit of the first preset opening range is less than the third preset difference, and the condensate temperature of the non-isolated sector is greater than the preset temperature, the up-cut step sequence is executed.

[0018] Optionally, the execution of the down-cut step sequence includes:

[0019] When the first duration is greater than the preset duration and the value obtained by subtracting the upper limit of the first preset opening range from the shutter opening of the non-isolated sector is greater than the fourth preset difference, the down-cut step sequence is executed.

[0020] Optionally, setting the first target sector as the new operating sector includes:

[0021] Determining whether there is at least one currently non-operating sector;

[0022] If so, setting the first target sector as the new operating sector;

[0023] Otherwise, the method further includes:

[0024] changing the control mode of the louver of the currently operating sector from automatic adjustment within a first preset opening range to automatic adjustment within a second preset opening range.

[0025] Optionally, if the current working condition is a summer working condition, the up-cut sequence includes:

[0026] setting the control mode of the louver opening of the currently operating sector to automatic adjustment within a third preset opening range, where the lower limit of the third preset opening range is the lower limit of the first preset opening range, and the upper limit of the third preset opening range is the upper limit of the second preset opening range.

[0027] In a second aspect, the present application provides a back pressure adjustment device for a natural ventilation direct air-cooled system, including:

[0028] an acquisition module for acquiring the current back pressure of the steam turbine;

[0029] a first processing module for performing an up-cut sequence when the current back pressure is greater than the set back pressure and the difference is greater than a first preset difference. Wherein, if the current working condition is a winter working condition, the up-cut sequence includes: setting a first target sector as the new operating sector, and setting the control mode of the louver opening of the new operating sector to automatic adjustment within a first preset opening range, and the first target sector is one of the sectors that are not currently operating;

[0030] a second processing module for performing a down-cut sequence when the current back pressure is less than the set back pressure and the difference is greater than a second preset difference. Wherein, if the current working condition is a winter working condition, the down-cut sequence includes: changing the control mode of the louver of the second target sector from automatic adjustment within a second preset opening range to automatic adjustment within the first preset opening range until the second target sector exits operation, and the second target sector is one of the currently operating sectors, and the lower limit of the second preset opening range is the upper limit of the first preset opening range.

[0031] Optionally, when the first target sector is a sector provided with a steam isolation valve, the up-cut sequence further includes:

[0032] opening the condensate isolation valve and the steam isolation valve of the first target sector, and reducing the louver opening of the currently operating sector to the current opening;

[0033] and / or, when the second target sector is a sector provided with a steam isolation valve, the down-cut sequence further includes:

[0034] Close the condensate isolation valve and the steam isolation valve of the second target sector.

[0035] Optionally, after the obtaining module obtains the current back pressure of the steam turbine, it is further configured to:

[0036] Obtain a first duration, a current louver opening degree, and a condensate temperature of an unisolated sector, where the first duration is the duration between the moment corresponding to the last execution of the step sequence to adjust the back pressure and the current moment;

[0037] When the first processing module executes the up-cut step sequence, it is specifically configured to:

[0038] When the first duration is greater than a preset duration, and the value obtained by subtracting the louver opening degree of the currently operating sector from the upper limit of the first preset opening degree range is less than a third preset difference, and the condensate temperature of the unisolated sector is greater than a preset temperature, execute the up-cut step sequence.

[0039] Optionally, when the second processing module executes the down-cut step sequence, it is specifically configured to:

[0040] When the first duration is greater than the preset duration, and the value obtained by subtracting the upper limit of the first preset opening degree range from the louver opening degree of the unisolated sector is greater than a fourth preset difference, execute the down-cut step sequence.

[0041] Optionally, when the first processing module sets the first target sector as the new operating sector, it is specifically configured to:

[0042] Determine whether there is at least one currently un-operating sector;

[0043] If so, set the first target sector as the new operating sector;

[0044] Otherwise, the method further includes:

[0045] Change the control mode of the louver of the currently operating sector from automatic adjustment within the first preset opening degree range to automatic adjustment within the second preset opening degree range.

[0046] Optionally, if the current working condition is a summer working condition, the up-cut step sequence includes:

[0047] Set the control mode of the louver opening degree of the currently operating sector to automatic adjustment within a third preset opening degree range, where the lower limit of the third preset opening degree range is the lower limit of the first preset opening degree range, and the upper limit of the third preset opening degree range is the upper limit of the second preset opening degree range.

[0048] In a third aspect, the present application provides an electronic device, including: a processor and a memory;

[0049] The memory stores computer execution instructions;

[0050] The processor executes the computer-executable instructions stored in the memory, causing the processor to execute the method described in any item of the first aspect.

[0051] In a fourth aspect, an embodiment of the present application provides a readable storage medium, including a program or instructions. When the program or instructions are run on a computer, the method described in any item of the above first aspect is executed.

[0052] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program. When the computer program is executed by a processor, the method described in any item of the first aspect is implemented.

[0053] The method and device for adjusting the back pressure of the natural ventilation direct air-cooling system provided by the present application, by obtaining the current back pressure of the steam turbine. When the current back pressure is greater than the set back pressure and the difference is greater than the first preset difference, the up-cut step sequence is executed. Among them, if the current working condition is the winter working condition, the up-cut step sequence includes: setting the first target sector as the new operating sector, and setting the control mode of the louver opening of the new operating sector to be automatically adjusted within the first preset opening range. The first target sector is one of the sectors that are not currently in operation; when the current back pressure is less than the set back pressure and the difference is greater than the second preset difference, the down-cut step sequence is executed. Among them, if the current working condition is the winter working condition, the down-cut step sequence includes: adjusting the control mode of the louver of the second target sector from being automatically adjusted within the second preset opening range to being automatically adjusted within the first preset opening range until the second target sector exits operation. The second target sector is one of the sectors that are currently in operation, and the lower limit of the second preset opening range is the upper limit of the first preset opening range. By controlling the automatic switching of sectors and the automatic adjustment of the louver opening, the automatic adjustment of the back pressure is realized, the degree of automation of the back pressure adjustment is improved, and further the accuracy and efficiency of the back pressure adjustment are improved, thereby improving the efficiency of the generator set. Description of the Drawings

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0055] Figure 1 It is a flowchart of the method for adjusting the back pressure of the natural ventilation direct air-cooling system provided by an embodiment of the present application;

[0056] Figure 2 It is a schematic structural diagram of the natural ventilation direct air-cooling system provided by an embodiment of the present application;

[0057] Figure 3 Structural schematic diagram of the back pressure adjustment device for the natural ventilation direct air cooling system provided by an embodiment of the present application

[0058] Figure 4 Structural schematic diagram of the electronic device provided by an embodiment of the present application Detailed implementation manners

[0059] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below. Apparently, the described embodiments are some but not all of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall also fall within the protection scope of the present application

[0060] For the natural ventilation direct air cooling system NDC, a natural ventilation cooling tower is generally provided. Inside the natural ventilation cooling tower, the exhaust steam of the steam turbine (i.e., the cooling water to be cooled) is sent to the air-cooled condenser through the exhaust steam pipeline. The cold air enters the tower from the bottom of the natural ventilation cooling tower, cools the exhaust steam in the air-cooled condenser into water, and the condensate is then pumped back to the regenerative system of the steam turbine through the condensate pump. The heated cold air leaves the cooling tower from the top of the tower

[0061] Among them, when the generator set is already in operation, the back pressure is adjusted according to reasons such as power generation requirements, operating status of the generator set, and environmental changes. At present, for the back pressure adjustment of the natural ventilation direct air cooling system NDC, most still adopt the back pressure adjustment method of the indirect air cooling system, that is, manual adjustment. However, in the natural ventilation direct air cooling system NDC, the exhaust steam of the steam turbine is directly condensed by air, and its back pressure changes with the ambient air temperature. Especially in areas with large temperature differences, the back pressure fluctuates greatly. The manual adjustment method not only has low efficiency, but also has large adjustment errors, affecting the efficiency of the generator set

[0062] Therefore, to solve the technical problems existing in the prior art, the present application proposes a back pressure adjustment method and device for the natural ventilation direct air cooling system. When the back pressure needs to be adjusted, the back pressure is roughly adjusted by automatically controlling the switching of sectors, that is, sector operation and sector withdrawal from operation, and the relationship between the louver opening and the back pressure is set, and the back pressure is finely adjusted by automatically controlling the louver opening, which not only realizes the automatic adjustment of the back pressure, but also ensures the accuracy of the back pressure adjustment

[0063] First, the embodiments of the present application introduce the structure of the natural ventilation direct air cooling system. The natural ventilation direct air cooling system includes: a plurality of sectors, each sector includes 3 cooling triangles, each cooling triangle corresponds to a set of louvers, and a temperature measuring point is provided on each cooling triangle, and the temperature measuring point is used to measure the condensate temperature

[0064] The present application will be described by taking the above natural ventilation direct air cooling system as an example:

[0065] Figure 1 The flowchart of the back pressure adjustment method for the natural ventilation direct air cooling system provided by an embodiment of the present application. The execution subject of the method in this embodiment can be, for example, a Distributed Control System (DCS). The method in this embodiment includes:

[0066] S101. Obtain the current back pressure of the steam turbine.

[0067] In this implementation, a pressure transmitter is installed on the main steam pipeline of the steam turbine. The pressure transmitter measures the pressure signal of the main steam pipeline, converts the pressure signal into an electrical signal, and transmits it to the DCS. The DCS processes the electrical signal to obtain the current back pressure.

[0068] Among them, multiple pressure transmitters can be installed on the main steam pipeline of the steam turbine. For example, 3 pressure transmitters are used to measure the pressure signal of the main steam pipeline. The DCS uses a 2-out-of-3 logic to determine the current back pressure.

[0069] S102. When the current back pressure is greater than the set back pressure and the difference is greater than the first preset difference, execute the up-cut step sequence. Among them, if the current working condition is a winter working condition, the up-cut step sequence includes: setting the first target sector as the new operating sector, and setting the control mode of the louver opening of the new operating sector to automatically adjust within the first preset opening range.

[0070] Among them, the first target sector is one of the sectors that are not currently in operation.

[0071] In this implementation, the set back pressure is set according to the load of the generator set, the ambient temperature, etc. When the ambient temperature and the load of the generator set change, the back pressure needs to be reset, resulting in a change in the back pressure of the steam turbine, causing the current back pressure to be inconsistent with the set back pressure. Or when the ambient temperature changes violently in a short period of time, the current back pressure of the steam turbine changes, thus being inconsistent with the set back pressure. Therefore, when the current back pressure is inconsistent with the set back pressure, the current back pressure needs to be adjusted.

[0072] Compare the current back pressure with the set back pressure. When the current back pressure is greater than the set back pressure and the difference is large, greater than the first preset difference, the up-cut step sequence needs to be executed. Among them, the first preset difference can be set according to the actual situation. For example, the first preset difference can be 2 kPa. Up-cut means adjusting the current back pressure by increasing the louver opening and / or sector operation.

[0073] For the winter condition, when the back pressure increases, first adjust the opening degree of the louvers in the sectors that have been put into operation, so that the louvers in the sectors that have been put into operation are automatically adjusted within the first preset opening range, causing the current back pressure to increase. Among them, the first preset opening range includes: when the ambient temperature ≤ -29°C, the louver opening is automatically adjusted at 0% - 25% opening; when -29°C < ambient temperature ≤ -25°C, the louver opening is automatically adjusted at 0% - 30% opening; when -25°C < ambient temperature ≤ -20°C, the louver opening is automatically adjusted at 0% - 35% opening; when -20°C < ambient temperature ≤ -15°C, the louver opening is automatically adjusted at 0% - 40% opening; when -15°C < ambient temperature ≤ -10°C, the louver opening is automatically adjusted at 0% - 45% opening; when -10°C < ambient temperature ≤ -5°C, the louver opening is automatically adjusted at 0% - 50% opening; when -5°C < ambient temperature ≤ 5°C, the louver opening is automatically adjusted at 0% - 55% opening.

[0074] When it is difficult to make the current back pressure meet the set back pressure by adjusting the opening degree of the louvers in the sectors that have been put into operation, that is, when the difference between the current back pressure and the set back pressure is large, increase the back pressure by adding a sector to be put into operation. Determine one of the sectors that have not been put into operation as the first target sector, put the first target sector into operation, and set the control mode of the opening degree of the louvers in the first target sector to be automatically adjusted within the first preset opening range.

[0075] After putting the first target sector into operation according to the up-cut step sequence described in S102, when the current back pressure is still greater than the set back pressure by 2 kPa, loop the up-cut step sequence described in S102 until the value by which the current back pressure is greater than the set back pressure is less than 2 kPa.

[0076] Optionally, in a natural ventilation direct air-cooled system, the sectors are divided into sectors with steam isolation valves and sectors without steam isolation valves. For the sectors with steam isolation valves, the steam isolation valves need to be opened before they are put into operation. Therefore, when the first target sector is a sector with a steam isolation valve, S102 further includes: opening the condensate isolation valve and the steam isolation valve of the first target sector, and reducing the opening degree of the louvers in the currently operating sectors to the current opening degree.

[0077] Specifically, for the sectors with steam isolation valves, when this sector is used as the first target sector, before this sector is put into operation, the condensate isolation valve and the steam isolation valve need to be opened so that this sector can operate normally after it is put into operation.

[0078] And, the opening degree of the louvers in the currently operating sectors also needs to be reduced, for example, reduced to half of the current opening degree, to avoid a large change in the back pressure of the steam turbine after adding a sector to be put into operation, which affects the operation of the generator set.

[0079] Optionally, when all sectors in the natural draft direct air cooling system have been put into operation, if the front back pressure is greater than the set back pressure, at this time, one implementation of "setting the first target sector as the newly put into operation sector" in S102 is as follows:

[0080] S102a. Determine whether there is at least one currently unput into operation sector. If so, execute S102b; otherwise, execute S102c.

[0081] S102b. Set the first target sector as the newly put into operation sector.

[0082] S102c. Change the control mode of the louvers of the currently put into operation sector from automatically adjusting within the first preset opening range to automatically adjusting within the second preset opening range.

[0083] Specifically, when all sectors in the natural draft direct air cooling system have been put into operation, but the current back pressure is still greater than the set back pressure, the back pressure is adjusted by increasing the opening of the louvers. At this time, the minimum value of the opening of the louvers is increased so that the opening of the louvers is automatically adjusted within the second preset opening range. Among them, the lower limit of the second preset opening range is the upper limit of the first preset opening range. For example, if the upper limit of the first preset opening range is 55%, then the lower limit of the second preset opening range is 55%, and the upper limit of the second preset opening range can be 100%, thereby increasing the opening of the louvers and adjusting the back pressure.

[0084] Optionally, for the summer working condition, the "up-cut step sequence" in S102 is specifically: setting the control mode of the opening of the louvers of the currently put into operation sector to automatically adjust within the third preset opening range.

[0085] Among them, the lower limit of the third preset opening range is the lower limit of the first preset opening range, and the upper limit of the third preset opening range is the upper limit of the second preset opening range.

[0086] Specifically, in summer, the temperature is relatively high. In order to meet the cooling requirements of the natural draft air cooling system and the summer temperature difference change, the adjustment range of the opening of the louvers should be relatively large. Therefore, in summer, the adjustment range of the opening of the louvers of the currently put into operation sector is the third preset opening range, where the lower limit of the third preset opening range is the lower limit of the first preset opening range and the upper limit is the upper limit of the second preset opening range, that is, the third preset opening range is [0, 100%].

[0087] In summer, by expanding the adjustment range of the opening of the louvers so that it automatically adjusts within [0, 100%], the back pressure of the steam turbine can be accurately and flexibly adjusted and controlled, and the efficiency of the generator set can be improved.

[0088] S103. When the current back pressure is less than the set back pressure and the difference is less than the first preset difference, perform the down-cut procedure. Among them, if the current working condition is the winter working condition, the down-cut procedure includes: changing the control mode of the louvers of the second target sector from automatically adjusting within the second preset opening range to automatically adjusting within the first preset opening range until the second target sector is taken out of service.

[0089] Among them, the second target sector is one of the currently operating sectors, and the lower limit of the second preset opening range is the upper limit of the first preset opening range.

[0090] In this embodiment, when the current back pressure is less than the set back pressure by 2 kPa, the down-cut procedure needs to be performed. Among them, down-cut means adjusting the current back pressure by reducing the opening of the louvers and / or taking the sector out of service.

[0091] When all sectors of the natural ventilation direct air-cooled system are in operation and the opening of the louvers is automatically adjusted within the second preset opening range, when the current back pressure needs to increase, the opening of the louvers of any one of the operating sectors, that is, the second target sector, can be adjusted first. That is, change the control mode of the opening of the louvers of the second target sector from automatically adjusting within the second preset opening range to automatically adjusting within the first preset opening range, so that the opening of the louvers of the second target sector is automatically adjusted within the first preset opening range.

[0092] Among them, since the lower limit of the first preset opening range is 0, therefore, according to the difference between the current back pressure and the set back pressure, when the opening of the louvers of the second target sector is 0, this sector is taken out of service.

[0093] Optionally, among the already operating sectors, for the sectors equipped with steam isolation valves, if this sector needs to be taken out of service, in S103, after "changing the control mode of the louvers of the second target sector from automatically adjusting within the second preset opening range to automatically adjusting within the first preset opening range", it further includes: closing the condensate isolation valve and the steam isolation valve of the second target sector.

[0094] Specifically, for the second target sector equipped with a steam isolation valve, when the opening of the louvers of this sector is 0 and it is taken out of service, it is necessary to close the condensate isolation valve and the steam isolation valve of this sector.

[0095] It should be noted that when the second target sector is taken out of service according to the down-cut procedure described in S103 and the current back pressure is still less than the set back pressure, loop the down-cut procedure described in S103 until the value by which the current back pressure is less than the set back pressure is within the second preset range.

[0096] Optionally, for the summer operating condition, the "down-step sequence" in S102 is specifically as follows: Set the control mode of the louver opening of the currently operating sector to automatically adjust within the third preset opening range, where the lower limit of the third preset opening range is the lower limit of the first preset opening range, and the upper limit of the third preset opening range is the upper limit of the second preset opening range.

[0097] Specifically, for the summer operating condition, since there is no risk of freezing, in summer, that is, under the summer operating condition, generally all sectors of the natural ventilation direct air cooling system are put into operation, and the control mode of the louver opening of each sector is set to automatically adjust within the third preset opening range. Specifically, reference can be made to the up-step sequence corresponding to the summer operating condition.

[0098] That is to say, in summer, that is, under the summer operating condition, all sectors of the natural ventilation direct air cooling system are put into operation, and the control mode of the louver opening of each sector is set to automatically adjust within the third preset opening range. According to the difference between the current back pressure and the set back pressure, the opening of the louver is automatically adjusted within the third preset opening range. That is, when the current back pressure is greater than the set back pressure, the opening of the louver is increased; when the current back pressure is less than the set back pressure, the opening of the louver is decreased.

[0099] In this embodiment, by obtaining the current back pressure of the steam turbine, when the current back pressure is greater than the set back pressure and the difference is greater than the first preset difference, the up-step sequence is executed. Among them, if the current operating condition is the winter operating condition, the up-step sequence includes: setting the first target sector as the new operating sector, and setting the control mode of the louver opening of the new operating sector to automatically adjust within the first preset opening range, where the first target sector is one of the sectors that are not currently in operation; when the current back pressure is less than the set back pressure and the difference is greater than the second preset difference, the down-step sequence is executed. Among them, if the current operating condition is the winter operating condition, the down-step sequence includes: adjusting the control mode of the louver of the second target sector from automatically adjusting within the second preset opening range to automatically adjusting within the first preset opening range until the second target sector exits operation, where the second target sector is one of the sectors that are currently in operation, and the lower limit of the second preset opening range is the upper limit of the first preset opening range. By controlling the automatic switching of sectors and the automatic adjustment of the louver opening, the automatic adjustment of the back pressure is realized, the degree of automation of the back pressure adjustment is improved, and further the accuracy and efficiency of the back pressure adjustment are improved, thereby improving the efficiency of the generator set.

[0100] After performing an up-cut step sequence or a down-cut step sequence once, the back pressure of the steam turbine does not rapidly change to a difference from the set back pressure within the first preset range or the second preset range. Therefore, after performing an up-cut step sequence or a down-cut step sequence once, if it is detected that the difference between the current back pressure and the set back pressure exceeds the first preset range or the second preset range, and the DCS then performs an up-cut step sequence or a down-cut step sequence once, it will cause a relatively large change in the current back pressure, resulting in the difference between the current back pressure and the set back pressure always exceeding the first preset range or the second preset range, thus affecting the normal operation of the generator set.

[0101] Therefore, optionally, after S101, it further includes:

[0102] S104: Obtain the first duration, the current louver opening, and the condensate temperature of the unisolated sector.

[0103] Wherein, the first duration is the duration between the moment corresponding to the last execution of the step sequence to adjust the back pressure and the current moment.

[0104] In this embodiment, after the DCS executes a step sequence once, it records the time of executing the step sequence and starts timing to obtain the duration between the current moment and the moment corresponding to the last execution of the step sequence to adjust the back pressure.

[0105] The DCS also needs to record the current louver opening of the operating sector and the condensate temperature of the unisolated sector. Among them, for each unisolated sector, the condensate temperature can be obtained through the temperature measurement point. For the condensate temperatures measured by 3 temperature measurement points, the 3-out-of-2 logic is used to determine the condensate temperature of the unisolated sector. For example, the average value of the condensate temperatures measured by 2 temperature measurement points is selected as the condensate temperature of the unisolated sector.

[0106] Correspondingly, a specific implementation manner of "executing the up-cut step sequence" in S102 is:

[0107] S1021: When the first duration is greater than the first preset duration, and the louver opening of the current operating sector is less than the upper limit value of the first preset opening range by less than the first preset difference, and the condensate temperature of the unisolated sector is greater than the first preset temperature, execute the up-cut step sequence.

[0108] Specifically, the first preset duration can be set according to the actual situation. For example, it is set to 60s. Determine whether the first duration is greater than 60s, and determine that the louver opening of the current operating sector is smaller than the upper limit of the first preset opening range, and compare the difference with the first preset difference. For example, the first preset difference is 2%, and the condensate temperature of each unisolated sector is greater than the first preset temperature. Among them, the first preset temperature is, for example, 35°C.

[0109] When the first duration is greater than 60 s, the difference between the louver opening of the currently operating sector and the upper limit of the first preset opening range is less than 2%, and the condensate temperature of each unisolated sector is greater than 35°C, when the current back pressure is greater than the set back pressure, perform the up-cut sequence.

[0110] Correspondingly, a specific implementation manner of "performing the down-cut sequence" in S103 is as follows:

[0111] S1031. When the first duration is greater than the first preset duration, and the value by which the louver opening of the unisolated sector is greater than the upper limit of the first preset opening range is greater than the first preset difference, perform the down-cut sequence.

[0112] Specifically, when the current back pressure is less than the set back pressure, it is not necessary to measure the condensate temperature of the unisolated sector. However, it is necessary to obtain the louver opening of the unisolated sector, compare the louver opening of the unisolated sector with the upper limit of the first preset opening range, and when the louver opening of the unisolated sector is less than the upper limit of the first preset opening range, compare the difference with the first preset difference.

[0113] Therefore, when the first duration is greater than 60 s, the louver opening of the unisolated sector is less than the upper limit of the first preset opening range, and the difference is less than the first preset difference, when the current back pressure is less than the set back pressure, perform the down-cut sequence.

[0114] In this embodiment, by judging the first duration, the current louver opening, and the condensate temperature of the unisolated sector, the accuracy of performing the up-cut sequence is improved, and by judging the first duration and the louver opening of the unisolated sector, the accuracy of performing the down-cut sequence is improved.

[0115] Next, a specific embodiment is used to illustrate the back pressure adjustment method of the natural ventilation direct air cooling system of the present application. For a natural ventilation direct air cooling system, as Figure 2 shown, the natural ventilation direct air cooling system includes 13 sectors, namely sectors 0# - 12#. Among them, sectors 0# - 12# are circularly distributed. Starting from sector 0#, in the clockwise direction, they are sector 7#, sector 8#, sector 9#, sector 10#, sector 11#, sector 12#, sector 6#, sector 5#, sector 4#, sector 3#, sector 2#, and sector 1# in turn.

[0116] For the above natural ventilation direct air cooling system, the up-cut sequence of back pressure adjustment specifically includes:

[0117] S201. Obtain the current back pressure of the steam turbine;

[0118] S202. Obtain the first duration, the current louver opening, and the condensate temperature of the unisolated sector;

[0119] S203. When the current back pressure is greater than the set back pressure, the difference is greater than the first preset difference, the first duration is greater than the preset duration, the value obtained by subtracting the louver opening of the currently operating sector from the upper limit of the first preset opening range is less than the third preset difference, and the condensate temperature of the unsealed sector is greater than the preset temperature, perform the up-cut sequence step.

[0120] Among them, when the current working condition is the winter working condition, the up-cut sequence step includes:

[0121] S2011. The condensate isolation valves and steam isolation valves of sectors #3 to #10 are all closed, all the louvers of sectors #1 to #12 are closed, and the control mode of the louver opening of sector #0 is set to automatically adjust within the first preset opening range;

[0122] S2012. The control mode of the louver opening of sector #1 is set to automatically adjust within the first preset opening range;

[0123] S2013. The control mode of the louver opening of sector #7 is set to automatically adjust within the first preset opening range;

[0124] S2014. The control mode of the louver opening of sector #2 is set to automatically adjust within the first preset opening range;

[0125] S2015. The control mode of the louver opening of sector #8 is set to automatically adjust within the first preset opening range;

[0126] S2016. Open the condensate isolation valve and steam isolation valve of sector #6, and at the same time force the louver opening of the currently operating sector to be closed to 50% of the current opening, delay for 5 minutes, and the control mode of the louver opening of sector #6 is set to automatically adjust within the first preset opening range;

[0127] S2017. Open the condensate isolation valve and steam isolation valve of sector #12, and at the same time force the louver opening of the currently operating sector to be closed to 50% of the current opening, delay for 5 minutes, and the control mode of the louver opening of sector #12 is set to automatically adjust within the first preset opening range;

[0128] S2018. Open the condensate isolation valve and steam isolation valve of sector #5, and at the same time force the louver opening of the currently operating sector to be closed to 50% of the current opening, delay for 5 minutes, and the control mode of the louver opening of sector #5 is set to automatically adjust within the first preset opening range;

[0129] S2019. Open the condensate isolation valve and steam isolation valve of sector #11, and at the same time force the louver opening of the currently operating sector to be closed to 50% of the current opening, delay for 5 minutes, and the control mode of the louver opening of sector #6 is set to automatically adjust within the first preset opening range;

[0130] S2020. The condensate isolation valve and steam isolation valve of Sector #4 are opened. At the same time, the louver opening of the currently operating sector is forced to close to 50% of the current opening, with a 5-minute delay. The control mode of the louver opening of Sector #4 is set to automatically adjust within the first preset opening range;

[0131] S2021. The condensate isolation valve and steam isolation valve of Sector #10 are opened. At the same time, the louver opening of the currently operating sector is forced to close to 50% of the current opening, with a 5-minute delay. The control mode of the louver opening of Sector #10 is set to automatically adjust within the first preset opening range;

[0132] S2022. The condensate isolation valve and steam isolation valve of Sector #3 are opened. At the same time, the louver opening of the currently operating sector is forced to close to 50% of the current opening, with a 5-minute delay. The control mode of the louver opening of Sector #3 is set to automatically adjust within the first preset opening range;

[0133] S2023. The condensate isolation valve and steam isolation valve of Sector #9 are opened. At the same time, the louver opening of the currently operating sector is forced to close to 50% of the current opening, with a 5-minute delay. The control mode of the louver opening of Sector #9 is set to automatically adjust within the first preset opening range;

[0134] S2024. After all sectors from 0# to 12# are put into operation, the control mode of the louver opening of sectors 0# - 12# is set to automatically adjust within the second preset opening range.

[0135] It should be noted that during the execution of the up-cut step sequence, when the down-cut step sequence needs to be executed, at the current up-cut step sequence, the down-cut step sequence can be executed according to the down-cut step sequence.

[0136] It should also be noted that the above is the up-cut step sequence under winter conditions. For the up-cut step sequence under summer conditions, reference can be made to the above text and will not be elaborated here.

[0137] For the above natural ventilation direct air-cooled system, the down-cut step sequence for back pressure adjustment specifically includes:

[0138] S301. Obtain the current back pressure of the steam turbine;

[0139] S302. Obtain the first duration and the current louver opening;

[0140] S303. When the current back pressure is less than the set back pressure, and the difference is greater than the first preset difference, and the first duration is greater than the preset duration, and the value obtained by subtracting the louver opening of the unisolated sector from the upper limit of the first preset opening range is less than the third preset difference, execute the down-cut step sequence.

[0141] Among them, the current working condition is the winter working condition, and the following cutting sequence includes:

[0142] S3011. All sectors from 0# to 12# are put into operation, and the control mode of the louver opening of sectors 0# to 12# is set to automatically adjust within the second preset opening range;

[0143] S3012. The control mode of the louver opening of sector #9 is set to automatically adjust within the first preset opening range. When the louver of sector #9 is closed (opening < 2%), the steam isolation valve of sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed after 20 minutes;

[0144] S3013. The control mode of the louver opening of sector #3 is set to automatically adjust within the first preset opening range. When the louver of sector #3 is closed (opening < 2%), the steam isolation valve of sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed after 20 minutes;

[0145] S3014. The control mode of the louver opening of sector #10 is set to automatically adjust within the first preset opening range. When the louver of sector #10 is closed (opening < 2%), the steam isolation valve of sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed after 20 minutes;

[0146] S3015. The control mode of the louver opening of sector #4 is set to automatically adjust within the first preset opening range. When the louver of sector #4 is closed (opening < 2%), the steam isolation valve of sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed after 20 minutes;

[0147] S3016. The control mode of the louver opening of sector #11 is set to automatically adjust within the first preset opening range. When the louver of sector #11 is closed (opening < 2%), the steam isolation valve of sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed after 20 minutes;

[0148] S3017. The control mode of the louver opening of sector #5 is set to automatically adjust within the first preset opening range. When the louver of sector #5 is closed (opening < 2%), the steam isolation valve of sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed after 20 minutes;

[0149] S3018. The control mode of the louver opening of sector #12 is set to automatically adjust within the first preset opening range. When the louver of sector #12 is closed (opening < 2%), the steam isolation valve of sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed after 20 minutes;

[0150] S3019. The control mode of the louver opening of Sector #6 is set to automatically adjust within the first preset opening range. When the louver of Sector #6 is closed (opening < 2%), the steam isolation valve of Sector #9 is automatically closed, and the corresponding condensate isolation valve is automatically closed 20 minutes later.

[0151] S3020. The control mode of the louver opening of Sector #8 is set to automatically adjust within the first preset opening range.

[0152] S3021. The control mode of the louver opening of Sector #2 is set to automatically adjust within the first preset opening range.

[0153] S3022. The control mode of the louver opening of Sector #7 is set to automatically adjust within the first preset opening range.

[0154] S3023. The control mode of the louver opening of Sector #1 is set to automatically adjust within the first preset opening range.

[0155] S3024. The control mode of the louver opening of Sector #0 is set to automatically adjust within the first preset opening range.

[0156] It should be noted that when performing the down-cut step sequence, when the up-cut step sequence needs to be executed, the up-cut step sequence can be directly executed on the basis of the currently executed down-cut step sequence.

[0157] It should also be noted that the above is the down-cut step sequence under winter conditions. For the down-cut step sequence under summer conditions, reference can be made to the above text and will not be elaborated here.

[0158] Figure 3 This is a schematic structural diagram of a back pressure adjustment device for a natural ventilation direct air-cooled system provided by an embodiment of the present application. As Figure 3 shown, the device includes: an acquisition module 310, a first processing module 320, and a second processing module 330.

[0159] The acquisition module 310 is used to acquire the current back pressure of the steam turbine.

[0160] The first processing module 320 is used to execute the up-cut step sequence when the current back pressure is greater than the set back pressure and the difference is greater than the first preset difference. Wherein, if the current working condition is winter, the up-cut step sequence includes: setting a first target sector as a new operating sector, and setting the control mode of the louver opening of the new operating sector to automatically adjust within the first preset opening range, and the first target sector is one of the sectors that are not currently in operation.

[0161] The second processing module 330 is configured to perform a down-cut sequence when the current back pressure is less than the set back pressure and the difference is greater than a second preset difference. Wherein, if the current working condition is a winter working condition, the down-cut sequence includes: adjusting the control mode of the louvers of the second target sector from automatically adjusting within a second preset opening range to automatically adjusting within the first preset opening range until the second target sector exits operation. The second target sector is one of the currently operating sectors, and the lower limit of the second preset opening range is the upper limit of the first preset opening range.

[0162] Optionally, when the first target sector is a sector provided with a steam isolation valve, the up-cut sequence further includes:

[0163] Opening the condensate isolation valve and the steam isolation valve of the first target sector, and reducing the louver opening of the currently operating sector to the current opening;

[0164] And / or, when the second target sector is a sector provided with a steam isolation valve, the down-cut sequence further includes:

[0165] Closing the condensate isolation valve and the steam isolation valve of the second target sector.

[0166] Optionally, after the acquisition module 310 acquires the current back pressure of the steam turbine, it is further configured to:

[0167] Acquire a first duration, the current louver opening, and the condensate temperature of the non-isolated sector, where the first duration is the duration between the moment corresponding to the last execution of the sequence to adjust the back pressure and the current moment;

[0168] When the first processing module 320 executes the up-cut sequence, it is specifically configured to:

[0169] When the first duration is greater than a preset duration, the value obtained by subtracting the louver opening of the currently operating sector from the upper limit of the first preset opening range is less than a third preset difference, and the condensate temperature of the non-isolated sector is greater than a preset temperature, execute the up-cut sequence.

[0170] Optionally, when the second processing module 330 executes the down-cut sequence, it is specifically configured to:

[0171] When the first duration is greater than the preset duration and the value obtained by subtracting the upper limit of the first preset opening range from the louver opening of the non-isolated sector is greater than a fourth preset difference, execute the down-cut sequence.

[0172] Optionally, when the first processing module 320 sets the first target sector as the new operating sector, it is specifically configured to:

[0173] Determine whether there is at least one currently non-operating sector;

[0174] If so, set the first target sector as the newly put-into-operation sector;

[0175] Otherwise, the method further includes:

[0176] Change the control mode of the louvers of the current put-into-operation sector from automatically adjusting within the first preset opening range to automatically adjusting within the second preset opening range.

[0177] Optionally, if the current working condition is a summer working condition, the up-cut step sequence includes:

[0178] Set the control mode of the louver opening of the current put-into-operation sector to automatically adjust within a third preset opening range, where the lower limit of the third preset opening range is the lower limit of the first preset opening range, and the upper limit of the third preset opening range is the upper limit of the second preset opening range.

[0179] For the back pressure adjustment device of the natural ventilation direct air-cooling system provided by the embodiments of the present application, its specific implementation process can be referred to the above method embodiments, and its implementation principle and technical effects are similar, which will not be elaborated here in this embodiment.

[0180] Figure 4 It is a schematic structural diagram of an electronic device provided by an embodiment of the present application. As Figure 4 shown, the electronic device includes: a processor 410 and a memory 420.

[0181] Wherein, the memory 420 stores computer execution instructions.

[0182] The processor 410 executes the computer execution instructions stored in the memory 420, so that the processor 410 executes the method described in any of the above embodiments.

[0183] For the electronic device provided by the embodiments of the present application, its specific implementation process can be referred to the above method embodiments, and its implementation principle and technical effects are similar, which will not be elaborated here in this embodiment.

[0184] In the above Figure 4In the embodiments shown, it should be understood that the processor can be a Central Processing Unit (CPU), or it can also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor, etc. The steps of the method disclosed in combination with the invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor.

[0185] The memory may include high-speed RAM memory and may also include non-volatile storage NVM, such as at least one disk memory.

[0186] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, the buses in the drawings of this application are not limited to only one bus or one type of bus.

[0187] The embodiments of this application also provide a computer-readable storage medium. Computer-executable instructions are stored in the computer-readable storage medium. When the processor executes the computer-executable instructions, the method shown in the above method embodiments is implemented.

[0188] For the above computer-readable storage medium, the above-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic memory, flash memory, a magnetic disk or an optical disc. The readable storage medium can be any available medium accessible by a general or special-purpose computer.

[0189] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be part of the processor. The processor and the readable storage medium can be located in an Application Specific Integrated Circuits (ASIC). Of course, the processor and the readable storage medium can also exist as discrete components in a device.

[0190] Those of ordinary skill in the art will understand that all or part of the steps of implementing the above method embodiments can be completed by hardware associated with program instructions. The foregoing program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps including those of the above method embodiments; and the foregoing storage medium includes various media such as ROM, RAM, magnetic disks, or optical discs that can store program code.

[0191] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for adjusting the back pressure of a natural ventilation direct air cooling system, characterized in that, Including: Obtain the current back pressure of the steam turbine; When the current back pressure is greater than the set back pressure and the difference is greater than the first preset difference, execute the up-cut step sequence. Wherein, if the current working condition is a winter working condition, the up-cut step sequence includes: setting the first target sector as the new operating sector, and setting the control mode of the louver opening degree of the new operating sector to automatically adjust within the first preset opening range, and the first target sector is one of the sectors that are not currently in operation; When the current back pressure is less than the set back pressure and the difference is greater than the second preset difference, execute the down-cut step sequence. Wherein, if the current working condition is a winter working condition, the down-cut step sequence includes: adjusting the control mode of the louver of the second target sector from automatically adjusting within the second preset opening range to automatically adjusting within the first preset opening range until the second target sector exits operation. The second target sector is one of the currently operating sectors, and the lower limit of the second preset opening range is the upper limit of the first preset opening range.

2. The method according to claim 1, wherein When the first target sector is the sector provided with a steam isolation valve, the up-cut step sequence further includes: Opening the condensate isolation valve and the steam isolation valve of the first target sector, and reducing the louver opening degree of the currently operating sector to the current opening degree; And / or, when the second target sector is the sector provided with a steam isolation valve, the down-cut step sequence further includes: closing the condensate isolation valve and the steam isolation valve of the second target sector.

3. The method according to claim 1, wherein After obtaining the current back pressure of the steam turbine, it further includes: Obtain the first duration, the current louver opening degree, and the condensate temperature of the non-isolated sector, where the first duration is the duration between the moment corresponding to the last execution of the step sequence to adjust the back pressure and the current moment; Executing the up-cut step sequence includes: When the first duration is greater than the preset duration, the value obtained by subtracting the louver opening degree of the currently operating sector from the upper limit of the first preset opening range is less than the third preset difference, and the condensate temperature of the non-isolated sector is greater than the preset temperature, execute the up-cut step sequence.

4. The method according to claim 3, characterized in that, Executing the down-cut step sequence includes: When the first duration is greater than the preset duration and the value obtained by subtracting the upper limit of the first preset opening range from the louver opening degree of the non-isolated sector is greater than the fourth preset difference, execute the down-cut step sequence.

5. The method according to claim 1, wherein Setting the first target sector as the new operating sector includes: Determine whether there is at least one sector that is not currently in operation; If so, set the first target sector as the new operating sector; Otherwise, the method further includes: Adjusting the control mode of the louver of the currently operating sector from automatically adjusting within the first preset opening range to automatically adjusting within the second preset opening range.

6. The method according to claim 1, wherein If the current working condition is a summer working condition, the up-cut step sequence includes: Setting the control mode of the louver opening degree of the currently operating sector to automatically adjust within the third preset opening range, the lower limit of the third preset opening range is the lower limit of the first preset opening range, and the upper limit of the third preset opening range is the upper limit of the second preset opening range.

7. A back pressure adjustment device for a natural ventilation direct air cooling system, characterized in that, Including: An acquisition module for acquiring the current back pressure of the steam turbine; A first processing module, configured to perform an up-cut step when the current back pressure is greater than the set back pressure and the difference is greater than a first preset difference. Wherein, if the current working condition is a winter working condition, the up-cut step includes: setting a first target sector as a new operating sector, and setting the control mode of the louver opening degree of the new operating sector to be automatically adjusted within a first preset opening range, and the first target sector is one of the sectors that are not currently in operation; A second processing module, configured to perform a down-cut step when the current back pressure is less than the set back pressure and the difference is greater than a second preset difference. Wherein, if the current working condition is a winter working condition, the down-cut step includes: adjusting the control mode of the louver of the second target sector from being automatically adjusted within a second preset opening range to being automatically adjusted within the first preset opening range until the second target sector exits operation, the second target sector is one of the currently operating sectors, and the lower limit of the second preset opening range is the upper limit of the first preset opening range.

8. An electronic device, characterized in that, Comprising: A processor and a memory; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor executes the method according to any one of claims 1-6.

9. A readable storage medium, characterized in that, Comprising: A program or instruction, when the program or instruction runs on a computer, the method according to any one of claims 1-6 is executed.

10. A computer program product, characterized in that, Comprising: A computer program, which when executed by a processor implements the method according to any one of claims 1-6.

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