CN110207399A - Self-adaptive full-premix combustion control method - Google Patents
Self-adaptive full-premix combustion control method Download PDFInfo
- Publication number
- CN110207399A CN110207399A CN201811528089.3A CN201811528089A CN110207399A CN 110207399 A CN110207399 A CN 110207399A CN 201811528089 A CN201811528089 A CN 201811528089A CN 110207399 A CN110207399 A CN 110207399A
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- Prior art keywords
- gas
- gas flow
- adjust
- control method
- thermic load
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Links
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 24
- 239000007789 gas Substances 0.000 claims abstract description 95
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 35
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000003546 flue gas Substances 0.000 claims abstract description 5
- 230000003044 adaptive effect Effects 0.000 claims description 15
- 239000000779 smoke Substances 0.000 claims description 15
- 239000000567 combustion gas Substances 0.000 claims description 11
- 238000006243 chemical reaction Methods 0.000 claims description 8
- 239000003344 environmental pollutant Substances 0.000 abstract description 2
- 231100000719 pollutant Toxicity 0.000 abstract description 2
- 239000000126 substance Substances 0.000 abstract 1
- 239000002737 fuel gas Substances 0.000 description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 235000006508 Nelumbo nucifera Nutrition 0.000 description 1
- 240000002853 Nelumbo nucifera Species 0.000 description 1
- 235000006510 Nelumbo pentapetala Nutrition 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000001473 noxious effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/02—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details, e.g. noise reduction means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N1/00—Regulating fuel supply
- F23N1/02—Regulating fuel supply conjointly with air supply
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/18—Arrangement or mounting of grates or heating means
- F24H9/1809—Arrangement or mounting of grates or heating means for water heaters
- F24H9/1832—Arrangement or mounting of combustion heating means, e.g. grates or burners
- F24H9/1836—Arrangement or mounting of combustion heating means, e.g. grates or burners using fluid fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/20—Arrangement or mounting of control or safety devices
- F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
- F24H9/2035—Arrangement or mounting of control or safety devices for water heaters using fluid fuel
Abstract
The invention discloses a control method of self-adaptive full-premix combustion, which comprises the steps of collecting the water outlet temperature, the water inlet temperature and the water flow of a gas water heater, estimating the corresponding heat load when the heat efficiency is maximum according to the heat load curve relation, estimating the gas flow to be adjusted according to the heat load, and determining the adjustment of a gas proportional valve and a fan according to the comparison relation between the difference between the estimated gas flow to be adjusted and the current gas flow and a threshold value. The invention carries out PID accurate control on the gas flow through the gas proportional valve and the fan, ensures that the air and the gas are fully mixed according to the chemical equivalence ratio before combustion, and reduces pollutants in the discharged flue gas.
Description
Technical field
The invention belongs to gas heater technical fields, and in particular to a kind of control method of adaptive full premix combustion.
Background technique
In current existing gas-fired water heater, by the mixing of the combustion system of combustion gas, especially air and combustion gas
Ratio is different, can be divided into full premix combustion type and partly-premixed burning type.Wherein, full premix has the following characteristics that
After air and combustion gas are sufficiently mixed before burning according to stoichiometric ratio, then ignition is carried out, tool is permitted
More advantages, for example combustion gas full combustion, liberation are high, the thermal efficiency is high, noxious emission index is low etc. etc..But work as gas component
When changing, the air-fuel ratio of fuel gas buring is just changed, and fuel gas buring occurs abnormal.Due at this time air and combustion gas
Mixture cannot burn in the best condition, and the full premix combustion of script will appear thermal efficiency decline, burning abnormal sound, harmful smoke
The bad defects of combustion positions such as discharge increase.The present invention is in order to overcome this defect.
Summary of the invention
In view of this, the main purpose of the present invention is to provide a kind of control methods of adaptive full premix combustion.
In order to achieve the above objectives, the technical scheme of the present invention is realized as follows:
The embodiment of the present invention provides a kind of control method of adaptive full premix combustion, this method are as follows: acquisition gas and hot water
Device leaving water temperature, inflow temperature and water flow and corresponding heat is negative when estimating thermal efficiency maximum according to thermic load curved line relation
Lotus is estimated according to the thermic load and needs the gas flow that adjusts, according to the gas flow for needing to adjust and current estimated
The difference of gas flow and the comparison of threshold value determine adjustment to gas ratio valve and blower.
In above scheme, this method further include: preset thermic load curved line relation and the thermic load model of the water heater
It encloses and the corresponding gas flow range of the thermic load range and gas ratio valve open range.
In above scheme, this method further include: in gas heater booting, with the initial leaving water temperature of setting, combustion gas
Corresponding gas flow initial value and initial fan delivery work when ratio valve opening minimum.
It is described that the difference and threshold for needing the gas flow and current gas flow that adjust are estimated according in above scheme
The comparison of value determines the adjustment to gas ratio valve and blower, specifically: it is described that the combustion for needing to adjust is estimated according to
When the difference of throughput and current gas flow is greater than threshold value, first fan delivery is adjusted, then gas ratio valve is opened
Degree is adjusted；When the difference for estimating gas flow and current gas flow that needs adjust according to is less than threshold value,
First the aperture of gas ratio valve is adjusted, then fan delivery is adjusted；It is described to estimate what needs adjusted according to
When the difference of gas flow and current gas flow is equal to threshold value, the aperture and fan delivery of the gas ratio valve keep current
State.
In above scheme, the aperture of the gas ratio valve is adjusted to adjust the aperture of current gas ratio valve
To the corresponding state of gas flow estimated and need to adjust.
In above scheme, it is described estimated according to the thermic load need the gas flow that adjusts after, this method further include:
The exhaust smoke level for needing to adjust is estimated according to gas reaction formula and air coefficient.
In above scheme, the fan delivery is adjusted to adjust current fan delivery to described estimate and need to adjust
The corresponding state of whole exhaust smoke level.
In above scheme, the thermic load curved line relation is determined according to Q=c* Δ t*q/ η, wherein Q is thermic load, and c is
Water specific heat, η are the thermal efficiency, and Δ t is Inlet and outlet water temperature difference, that is, leaving water temperature tw2With inflow temperature tw1Difference, q is water flow.
In above scheme, this method further includes acquisition flue gas data, if the smoke machine data of acquisition do not reach standard value,
Air coefficient is increased.
Compared with prior art, the present invention accurately controls gas flow by gas ratio valve and blower progress PID, protects
It has demonstrate,proved air and combustion gas and has been sufficiently mixed and is reduced the pollutant in discharge flue gas according to stoichiometric ratio before burning.
Detailed description of the invention
Fig. 1 provides a kind of flow chart of the control method of adaptive full premix combustion for the embodiment of the present invention.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.
The embodiment of the present invention provides a kind of control method of adaptive full premix combustion, as shown in Figure 1, this method by with
Lower step is realized:
Step 101: presetting the thermic load range and the thermic load model of thermic load curved line relation and the water heater
Enclose corresponding gas flow range and gas ratio valve open range；
Specifically, the thermic load curved line relation is determined according to Q=c* Δ t*q/ η, wherein Q is thermic load, and c is water ratio
Heat, η are the thermal efficiency, and Δ t is Inlet and outlet water temperature difference, that is, leaving water temperature tw2With inflow temperature tw1Difference, q is water flow.
The load range of hot water apparatus is [QL, QH], then can determine gas flow range V1∈[VL1,VH1], it is corresponding
Gas proportion valve opening is P1∈[PL1,PH1]；
Exhaust smoke level range V is determined by fuel gas buring reaction equation and air coefficient α2∈[VL2,VH2], and then determine blower wind
The adjustable range of amount.
Theoretically fuel gas buring reaction equation makes combustion gas be reacted (such as CH with a certain proportion of oxygen4+2O2=CO2+
2H2O, combustion gas are reacted with oxygen 1:2), air only has the oxygen of 21% concentration in the middle, and combustion gas is burnt in air in reality
When, the air capacity needed is bigger than theory, and the ratio of actual air demand and theoretical air demand amount is exactly air system
Number α；
This method further includes that acquisition flue gas data measure excess oxygen, carbon monoxide, nitric oxide, exhaust gas temperature etc. respectively,
If the smoke machine data of acquisition do not reach standard value, i.e. α '=α+Δ α is increased to air coefficient.
The standard value is GB6932 standard and design value.
Step 102: in gas heater booting, when with the initial leaving water temperature of setting, gas proportion valve opening minimum
Corresponding gas flow initial value and initial fan delivery work；
Specifically, initial leaving water temperature is set as tw2, gas proportion valve opening minimum P0=PL1, gas flow setting value
For V0；
Acquire inflow temperature tw1And water flow q, the thermic load Q when η maximum is determined by thermic load curved line relation,
So that it is determined that gas flow V1 1(V1 1≥V0)；
It is determined by fuel gas buring reaction equation and air coefficient α and determines exhaust smoke level V, and by Fan Regulation smoke evacuation air quantity, made
Obtaining exhaust smoke level is V；
The default aperture of regulating gas proportioning valve, so that gas flow is V1。
Step 103: acquiring gas heater leaving water temperature, inflow temperature and water flow and closed according to thermic load curve
System estimates corresponding thermic load when thermal efficiency maximum；
Specifically, leaving water temperature tw is acquired2, inflow temperature tw1And water flow q, worked as by the determination of thermic load curved line relation
Thermic load Q when η maximum, and determine gas flow V1 n+1, exhaust smoke level V is determined by fuel gas buring reaction equation and air coefficient αn+1。
Step 104: the gas flow for needing to adjust is estimated according to the thermic load；
Specifically, gas flow V is determined according to the thermic load Q1 n+1。
Further, the exhaust smoke level for needing to adjust is estimated also according to gas reaction formula and air coefficient.
Exhaust smoke level V is determined by fuel gas buring reaction equation and air coefficient αn+1。
Step 105: according to the ratio of the difference for estimating gas flow and current gas flow that needs adjust and threshold value
The adjustment to gas ratio valve and blower is determined compared with relationship.
Specifically, described estimate according to needs the difference of the gas flow and current gas flow that adjust to be greater than threshold value
When, that is, V1 n+1-V1 n> 0, is first adjusted fan delivery, then is adjusted to the aperture of gas ratio valve；
It is described that i.e. V when the difference of the gas flow and current gas flow that adjust being needed to be less than threshold value is estimated according to1 n +1-V1 n< 0 is first adjusted the aperture of gas ratio valve, then is adjusted to fan delivery；
It is described that i.e. V when the difference of the gas flow and current gas flow that adjust being needed to be equal to threshold value is estimated according to1 n +1-V1 n=0, the aperture and fan delivery of the gas ratio valve keep current state.
The aperture of the gas ratio valve is adjusted to adjust the aperture of current gas ratio valve to V1 n+1It is corresponding
State.
The fan delivery is adjusted to adjust current fan delivery to Vn+1Corresponding state.
The foregoing is only a preferred embodiment of the present invention, is not intended to limit the scope of the present invention.
Claims (9)
1. a kind of control method of adaptive full premix combustion, which is characterized in that this method are as follows: acquisition gas heater goes out water temperature
Degree, inflow temperature and water flow and when thermal efficiency maximum is estimated according to thermic load curved line relation corresponding thermic load, according to
The thermic load estimates the gas flow for needing to adjust, and estimates the gas flow for needing to adjust and current combustion gas stream according to described
The difference of amount and the comparison of threshold value determine the adjustment to gas ratio valve and blower.
2. the control method of adaptive full premix combustion according to claim 1, which is characterized in that this method further include:
Preset the thermic load range and the corresponding gas flow of thermic load range of thermic load curved line relation and the water heater
Range and gas ratio valve open range.
3. the control method of adaptive full premix combustion according to claim 1 or 2, which is characterized in that this method is also wrapped
It includes: in gas heater booting, corresponding gas flow when with the initial leaving water temperature of setting, gas proportion valve opening minimum
Initial value and initial fan delivery work.
4. the control method of adaptive full premix combustion according to claim 4, which is characterized in that described according to described pre-
The comparison for estimating the difference and threshold value that need the gas flow and current gas flow that adjust is determined to gas ratio valve and wind
The adjustment of machine, specifically: described estimate according to needs the difference of the gas flow and current gas flow that adjust to be greater than threshold
When value, first fan delivery is adjusted, then the aperture of gas ratio valve is adjusted；Described estimate according to needs to adjust
When the difference of whole gas flow and current gas flow is less than threshold value, first the aperture of gas ratio valve is adjusted, then right
Fan delivery is adjusted；Described estimate according to needs the difference of the gas flow and current gas flow that adjust to be equal to threshold
When value, the aperture and fan delivery of the gas ratio valve keep current state.
5. the control method of adaptive full premix combustion according to claim 4, which is characterized in that the gas ratio valve
Aperture be adjusted to adjust the aperture of current gas ratio valve to described estimate and needing the gas flow that adjusts corresponding
State.
6. the control method of adaptive full premix combustion according to claim 5, which is characterized in that described according to the heat
After load estimates the gas flow for needing to adjust, this method further include: needs are estimated according to gas reaction formula and air coefficient
The exhaust smoke level of adjustment.
7. the control method of adaptive full premix combustion according to claim 6, which is characterized in that the fan delivery into
Row is adjusted to adjust current fan delivery to the corresponding state of exhaust smoke level estimated and need to adjust.
8. the control method of adaptive full premix combustion according to claim 7, which is characterized in that the thermic load curve
Relationship is determined according to Q=c* Δ t*q/ η, wherein Q is thermic load, and c is water specific heat, and η is the thermal efficiency, and Δ t is Inlet and outlet water temperature difference
That is leaving water temperature tw2With inflow temperature tw1Difference, q is water flow.
9. the control method of adaptive full premix combustion according to claim 8, which is characterized in that this method further includes adopting
Collect flue gas data, if the smoke machine data of acquisition do not reach standard value, air coefficient is increased.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811528089.3A CN110207399B (en) | 2018-12-13 | 2018-12-13 | Self-adaptive full-premix combustion control method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811528089.3A CN110207399B (en) | 2018-12-13 | 2018-12-13 | Self-adaptive full-premix combustion control method |
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| Publication Number | Publication Date |
|---|---|
| CN110207399A true CN110207399A (en) | 2019-09-06 |
| CN110207399B CN110207399B (en) | 2021-05-18 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110749105A (en) * | 2019-10-18 | 2020-02-04 | 华帝股份有限公司 | Active noise reduction fuel gas water heating device and method |
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| CN110207399B (en) | 2021-05-18 |
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