CN113638899A - Optimal back pressure adjusting method for direct air cooling unit - Google Patents
Optimal back pressure adjusting method for direct air cooling unit Download PDFInfo
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- CN113638899A CN113638899A CN202110799915.3A CN202110799915A CN113638899A CN 113638899 A CN113638899 A CN 113638899A CN 202110799915 A CN202110799915 A CN 202110799915A CN 113638899 A CN113638899 A CN 113638899A
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- 238000001816 cooling Methods 0.000 title claims abstract description 68
- 238000000034 method Methods 0.000 title claims abstract description 25
- 230000007613 environmental effect Effects 0.000 claims abstract description 17
- 238000005265 energy consumption Methods 0.000 claims abstract description 4
- 238000012360 testing method Methods 0.000 claims description 9
- 238000004891 communication Methods 0.000 claims description 3
- 238000012937 correction Methods 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims description 3
- 238000009529 body temperature measurement Methods 0.000 claims description 2
- 238000011156 evaluation Methods 0.000 claims description 2
- 238000010248 power generation Methods 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 7
- 230000001105 regulatory effect Effects 0.000 description 5
- 230000000903 blocking effect Effects 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 238000010977 unit operation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2270/00—Control
- F05D2270/30—Control parameters, e.g. input parameters
- F05D2270/303—Temperature
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Abstract
The invention discloses an optimal back pressure adjusting method for a direct air cooling unit, which belongs to the technical field of air cooling power generation, and is used for adjusting the operation condition of the air cooling unit and ensuring that steam inlet parameters and a valve position of a steam turbine are kept stable; the power of the unit is changed by changing the backpressure, so that the influence relation of the backpressure on the output of the unit is obtained; obtaining the relation between the fan energy consumption and the fan frequency under different fan frequencies by changing the operation frequency of the air cooling fan; under the condition that the load of the unit and the ambient temperature are not changed, the operating frequency of the air cooling fan is changed to change the backpressure of the unit, and the influence relation of the operating frequency of the air cooling fan on the backpressure is obtained. According to the invention, the optimal running backpressure of the unit under different environmental conditions can be obtained, and the running economy of the unit is improved; on the other hand, the blower power consumption of the unit is less under the same backpressure through the blower differential adjustment mode, and the plant power consumption rate of the direct air cooling unit is reduced.
Description
Technical Field
The invention relates to the technical field of air cooling power generation, in particular to an optimal back pressure adjusting method for a direct air cooling unit.
Background
In order to develop the power industry, most power plants use direct air cooling technology as a cooling scheme. The direct air cooling unit compares traditional wet cooling unit water economy resource, but owing to with fan forced draft cooling, consequently can lead to the station service to use the electricity far above wet cooling unit. The direct air cooling unit is greatly influenced by the environment, the influence of different wind directions, wind speeds and wind temperatures on fans of different units is different, and the influence of environmental change on the back pressure is more sensitive to the windward side than the back pressure side. For operators, in order to operate safely, the backpressure of the unit is generally controlled to be higher, and for convenience, the operators in summer and autumn only control the backpressure of the unit to be a certain higher value in a mode of operating the fan group in a blind manner, which is not favorable for economic operation of the unit: the group is operated the fan and has been increased the power consumption rate on the one hand, and on the other hand, blind setting backpressure is a certain value, may be higher than the minimum that it can reach in fact, and high back pressure unit economic nature is relatively poor.
Therefore, an optimal back pressure adjusting method for the direct air cooling unit is provided.
Disclosure of Invention
The invention aims to solve the problem that operators blindly set the backpressure as a value, which is unfavorable for economic operation of a unit; in order to achieve the backpressure value, the operation mode is that a plurality of fans are operated simultaneously, and the problem of influence of environmental wind at different positions on the fans is not considered, so that the optimal backpressure adjusting method for the direct air cooling unit is provided.
In order to achieve the purpose, the invention adopts the following technical scheme:
an optimal back pressure adjusting method for a direct air cooling unit comprises the following steps:
step 1, adjusting the operation condition of an air cooling unit to ensure that steam inlet parameters and valve positions of a steam turbine are kept stable;
step 2, changing the back pressure to change the power of the unit to obtain the influence relation of the back pressure on the output of the unit;
step 4, under the condition that the unit load and the ambient temperature are not changed, the operating frequency of the air cooling fan is changed to change the unit backpressure, so that the influence relation of the operating frequency of the air cooling fan on the backpressure is obtained;
step 6, finally determining the optimal operating back pressure of different loops of the air cooling system under different load working conditions through function curves of back pressure-power, back pressure-fan frequency and fan frequency-fan power consumption under specific load and specific environment temperature;
step 7, obtaining an optimal back pressure curve function of random group load and environmental temperature change through curve fitting according to the optimal back pressure of the unit under a specific working condition;
and 9, comparing according to the specific experimental data from the step 1 to the step 8 to obtain a conclusion.
Preferably, the evaluation values of the operation of the cooling fan in the step 3 are respectively 15Hz, 20Hz, 25Hz, 30Hz, 35Hz, 40Hz, 45Hz and 50 Hz.
Preferably, in the step 4, the fan frequency is changed according to 15Hz, 20Hz, 25Hz, 30Hz, 35Hz, 40Hz, 45Hz and 50Hz, and the relationship curve of the full operation condition of the air cooling fan to the back pressure is fitted through correction.
Preferably, the environmental temperature in step 5 is set to six working conditions of 5 ℃, 10 ℃, 15 ℃, 20 ℃, 25 ℃ and 30 ℃ respectively.
Preferably, in the step 8, the frequency of some fans is reduced on the premise that the backpressure of the unit is not changed through the differential control of the fans, so that the effect of saving the service power is achieved.
Preferably, the temperature measurements are made with the drone at 6kPa, 11kPa, 16kPa, 21kPa, 26kPa, 31kPa in step 8.
Preferably, the optimal back pressure curve of the unit, which is changed along with the load and the environmental condition, is obtained according to different loads of different environmental conditions and is set into the DCS.
Compared with the prior art, the invention provides an optimal backpressure adjusting method for a direct air cooling unit, which has the following beneficial effects:
1. the backpressure of the air-cooled power plant is reduced, the plant power consumption rate of the direct air-cooled power plant is reduced, and the operation economy of the direct air-cooled power plant is improved;
2. aiming at different environmental conditions and different loads, obtaining a unit optimal backpressure curve which changes along with the load and the environmental conditions, setting the curve into a DCS, and realizing the automatic operation of optimal backpressure on the premise of no intervention of operating personnel in a thermal automatic mode; the mode that the later stage passed through unmanned aerial vehicle scanning obtains air cooling island temperature field distribution, utilizes automatic operation to realize under the unchangeable prerequisite of backpressure, reduces the operating frequency of some fans to reduce the comprehensive station service power consumption rate of direct air cooling unit.
Drawings
FIG. 1 is a basic remote diagram of an optimal backpressure regulating method for a direct air cooling unit according to the present invention;
FIG. 2 is a schematic diagram showing the relationship between the fan frequency and the fan power consumption in the optimal backpressure regulating method for the direct air cooling unit according to the present invention;
fig. 3 is a schematic diagram illustrating a relationship between a fan frequency and a back pressure in an optimal back pressure adjusting method for a direct air cooling unit according to the present invention;
fig. 4 is a schematic diagram illustrating a relationship between back pressure and power variation values in an optimal back pressure adjusting method for a direct air cooling unit according to the present invention;
fig. 5 is a schematic diagram illustrating a relationship between loads and an optimal back pressure at different ambient temperatures in the method for adjusting the optimal back pressure of the direct air cooling unit according to the present invention;
fig. 6 is a diagram illustrating the influence of the fan frequency on the load and the fan power consumption under different temperatures under the 50% THA working condition in the optimal backpressure regulating method for the direct air cooling unit provided by the invention;
fig. 7 shows the influence of the fan frequency on the load and the fan power consumption under different temperatures under 75% THA working condition in the optimal backpressure regulating method for the direct air cooling unit provided by the invention;
fig. 8 shows the influence of the fan frequency on the load and the fan power consumption under different temperatures in the 75% THA working condition in the optimal backpressure regulating method for the direct air cooling unit provided by the invention;
fig. 9 is a table diagram of the optimization test results of the air-cooling fan in the optimal backpressure adjusting method for the direct air-cooling unit according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
Referring to fig. 1, an optimal back pressure adjusting method for a direct air cooling unit includes:
and the operation condition of the air cooling unit is adjusted to ensure that the steam inlet parameters and the valve position of the steam turbine are maintained stable. The power of the unit is changed by changing the backpressure, and the influence relation of the backpressure on the output of the unit is obtained. The back pressure changes to + -1 kPa, + -2 kPa, + -3 kPa.
Furthermore, the relation between the fan energy consumption and the fan frequency under different fan frequencies (15Hz, 20Hz, 25Hz, 30Hz, 35Hz, 40Hz, 45Hz and 50Hz) is obtained by changing the running frequency of the air cooling fan.
Furthermore, under the condition that the unit load and the ambient temperature are not changed, the unit backpressure is changed by changing the operation frequency of the air cooling fan, and the influence relation of the operation frequency of the air cooling fan on the backpressure is obtained. The frequency of the fan is changed according to 15Hz, 20Hz, 25Hz, 30Hz, 35Hz, 40Hz, 45Hz and 50Hz, and the relationship curve of the air cooling fan full operation working condition to the back pressure is fitted through correction.
Furthermore, the test is carried out on the curve functions of 'fan frequency-power consumption' and 'back pressure-fan frequency' obtained by the test at different environmental temperatures, wherein the environmental temperatures are respectively determined as six groups of working conditions of 5 ℃, 10 ℃, 15 ℃, 20 ℃, 25 ℃ and 30 ℃.
Furthermore, the optimal operation back pressure of different loops of the air cooling system under different load working conditions is finally determined through function curves of the back pressure-power, the back pressure-fan frequency and the fan frequency-fan power consumption under specific load and specific environment temperature.
Furthermore, according to the optimal back pressure of the unit under the specific working condition, an optimal back pressure curve function of random unit load and environmental temperature change is obtained through curve fitting, the target value (optimal back pressure) of the exhaust pressure of the air cooling fan of the unit is automatically changed by utilizing thermal control automatic adjustment, and the air cooling fan is ensured to be in the most economic operation frequency.
Further, an unmanned aerial vehicle is used for carrying an infrared thermal imager to measure a temperature field under 6kPa, 11kPa, 16kPa, 21kPa, 26kPa and 31kPa, air cooling temperature fields of different units in different rows and the same row under the same backpressure under a certain load and a certain environmental condition are obtained in a wireless communication mode, the frequency of certain fans is reduced on the premise that the backpressure of the unit is not changed through the differential control of the fans, the effect of saving station power is achieved, and the economical efficiency of unit operation is improved
Further, the optimal backpressure regulation optimization test is carried out on the large and Tang cloisonne power plant, and two groups of data are acquired under the working conditions of 100% load and 50% load (the unit is always loaded):
1. because the change of the ambient wind of the unit is large, the influence is ignored, and the optimal fan running frequency is calculated only from two aspects of temperature and load. 2. The influence relation of the backpressure of the unit on the load is calculated by software, and the electric quantity of a frequency converter of the fan is read by the power consumption of the fan. 3. And (3) extrapolating the maximum value of the difference between the influence of the backpressure of the unit on the power and the power consumption of the fan under different environmental temperature conditions under the working conditions of 50%, 75% and 100% of loads by using the data measured by the test.
In the invention, when the unit is under 50% load and the temperature range is between 5 and 15 ℃, the frequency is improved as much as possible on the premise of ensuring safety, so that the backpressure of the unit is close to the blocking backpressure, and the economical efficiency is best; 2. when the temperature range is 15-30 ℃, the fan frequency is kept at about 40Hz, and the economical efficiency is the best. 3. When the unit is 75% loaded and the temperature range is 5-15 ℃, the frequency is improved as much as possible on the premise of ensuring safety, so that the back pressure of the unit is close to the blocking back pressure, and the economy is best; 4. when the temperature range is 15-25 ℃, the fan frequency is kept at about 40Hz, and the economical efficiency is the best; after ambient temperatures exceed 30 ℃, the best economy can be achieved with overfrequency operation. 5. When the load of the unit is 100%, the temperature range is 5-30 ℃, the optimum unit operation backpressure can be obtained only by the overclocking operation, the economy is the best, and when the temperature is higher, the unit backpressure is reduced by adopting a peak spraying mode, so that the load limitation of the unit is prevented.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention and the equivalent alternatives or modifications according to the technical solution and the inventive concept of the present invention within the technical scope of the present invention.
Claims (7)
1. The optimal back pressure adjusting method for the direct air cooling unit is characterized by comprising the following steps of:
step 1, adjusting the operation condition of an air cooling unit to ensure that steam inlet parameters and valve positions of a steam turbine are kept stable;
step 2, changing the back pressure to change the power of the unit to obtain the influence relation of the back pressure on the output of the unit;
step 3, obtaining the relation between the fan energy consumption and the fan frequency under different fan frequencies by changing the operation frequency of the air cooling fan;
step 4, under the condition that the unit load and the ambient temperature are not changed, the operating frequency of the air cooling fan is changed to change the unit backpressure, so that the influence relation of the operating frequency of the air cooling fan on the backpressure is obtained;
step 5, testing the curve functions of 'fan frequency-power consumption' and 'back pressure-fan frequency' obtained by the tests in the step 2 and the step 3 in different environments;
step 6, finally determining the optimal operating back pressure of different loops of the air cooling system under different load working conditions through function curves of back pressure-power, back pressure-fan frequency and fan frequency-fan power consumption under specific load and specific environment temperature;
step 7, obtaining an optimal back pressure curve function of random group load and environmental temperature change through curve fitting according to the optimal back pressure of the unit under a specific working condition;
step 8, under different environments, an unmanned aerial vehicle is used for carrying an infrared thermal imager to measure the temperature, and air cooling temperature fields of different rows and the same row of different units under the same backpressure under the condition of a certain load and a certain environment are obtained in a wireless communication mode;
and 9, comparing according to the specific experimental data from the step 1 to the step 8 to obtain a conclusion.
2. The method for adjusting the optimal back pressure of the direct air cooling unit according to claim 1, wherein the evaluation values of the operation of the cooling fan in the step 3 are respectively 15Hz, 20Hz, 25Hz, 30Hz, 35Hz, 40Hz, 45Hz and 50 Hz.
3. The method for adjusting the optimal back pressure of the direct air cooling unit according to claim 1, wherein in the step 4, the fan frequency is changed according to 15Hz, 20Hz, 25Hz, 30Hz, 35Hz, 40Hz, 45Hz and 50Hz, and a relation curve of the full operation condition of the air cooling fan to the back pressure is fitted through correction.
4. The method for adjusting the optimal backpressure of the direct air cooling unit as claimed in claim 1, wherein the ambient temperature in step 5 is set to six working conditions of 5 ℃, 10 ℃, 15 ℃, 20 ℃, 25 ℃ and 30 ℃.
5. The method for adjusting the optimal back pressure of the direct air cooling unit according to claim 1, wherein in step 8, the frequency of some fans is reduced on the premise that the back pressure of the unit is not changed through the differential control of the fans, so that the effect of saving the service power is achieved.
6. The method for adjusting the optimal back pressure of the direct air cooling unit according to claim 1, wherein the temperature measurement is performed by an unmanned aerial vehicle at 6kPa, 11kPa, 16kPa, 21kPa, 26kPa and 31kPa in step 8.
7. The method for adjusting the optimal back pressure of the direct air cooling unit according to claim 1, wherein the optimal back pressure curve of the direct air cooling unit, which is changed with the load and the environmental condition, is obtained according to different loads of different environmental conditions and is set into DCS.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110799915.3A CN113638899A (en) | 2021-07-15 | 2021-07-15 | Optimal back pressure adjusting method for direct air cooling unit |
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| CN202110799915.3A CN113638899A (en) | 2021-07-15 | 2021-07-15 | Optimal back pressure adjusting method for direct air cooling unit |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114357023A (en) * | 2021-12-24 | 2022-04-15 | 朗坤智慧科技股份有限公司 | Direct air cooling unit operation optimization method and system based on data driving |
| CN114876841A (en) * | 2022-04-21 | 2022-08-09 | 西安热工研究院有限公司 | Method and device for controlling running frequency of air cooling fan and electronic equipment |
| CN117521499A (en) * | 2023-11-07 | 2024-02-06 | 北京大唐高鸿数据网络技术有限公司 | Optimal backpressure determination method, device, equipment and readable storage medium |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114357023A (en) * | 2021-12-24 | 2022-04-15 | 朗坤智慧科技股份有限公司 | Direct air cooling unit operation optimization method and system based on data driving |
| CN114876841A (en) * | 2022-04-21 | 2022-08-09 | 西安热工研究院有限公司 | Method and device for controlling running frequency of air cooling fan and electronic equipment |
| CN114876841B (en) * | 2022-04-21 | 2024-04-30 | 西安热工研究院有限公司 | Air cooling fan operation frequency control method and device and electronic equipment |
| CN117521499A (en) * | 2023-11-07 | 2024-02-06 | 北京大唐高鸿数据网络技术有限公司 | Optimal backpressure determination method, device, equipment and readable storage medium |
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Application publication date: 20211112 |