CN110207387A - Self-adaptive control method for air pressure system of gas water heater - Google Patents
Self-adaptive control method for air pressure system of gas water heater Download PDFInfo
- Publication number
- CN110207387A CN110207387A CN201811028095.2A CN201811028095A CN110207387A CN 110207387 A CN110207387 A CN 110207387A CN 201811028095 A CN201811028095 A CN 201811028095A CN 110207387 A CN110207387 A CN 110207387A
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- Prior art keywords
- pressure value
- target
- practical
- value
- adaptive
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- 238000000034 method Methods 0.000 title claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract 5
- 230000003044 adaptive effect Effects 0.000 claims abstract description 31
- 238000005070 sampling Methods 0.000 claims description 23
- 239000007789 gas Substances 0.000 claims 8
- 239000000567 combustion gas Substances 0.000 claims 1
- 238000013459 approach Methods 0.000 abstract description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 230000009897 systematic effect Effects 0.000 description 2
- 235000019504 cigarettes Nutrition 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
Classifications
-
- 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 self-adaptive control method of a wind pressure system of a gas water heater, which determines a maximum virtual pressure value Pmax and a minimum virtual pressure value Pmin as well as a maximum virtual pressure value Pmax and a minimum virtual pressure value Pmin of a fan corresponding to the maximum virtual pressure value Pmax and the minimum virtual pressure value Pmin respectively according to the rated load of the whole gas water heater and a formula P (R/M multiplied by K); determining a curve according to the maximum virtual pressure value Pmax, the minimum virtual pressure value Pmin and the proportional valve current; determining the actual pressure value P according to the curve and the formulaPractice ofAnd a target pressure value PTargetSaid actual pressure value PPractice ofAnd a target pressure value PTargetThe difference is used as the control deviation Err; the adaptive compensation is achieved by adjusting the control deviation Err to approach 0. The invention ensures that the air volume of the system can be adjusted in a self-adaptive manner under different use conditions to meet the performance requirements of the whole machine, and simultaneously meets the requirement that the protection function can be started in time under severe limit conditions, thereby avoiding the problems of damaging the internal system or causing safety accidents.
Description
Technical field
The invention belongs to gas heater technical fields, and in particular to a kind of control that gas heater air pressure system is adaptive
Method processed.
Background technique
There are mainly two types of control modes for systematic air flow compensation for the existing gas heater using DC fan:
1, corresponding air quantity is made to the wind pressure value monitoring of fixed point pressure sensor location by wind pressure sensing module to compensate；
2, system realizes that air quantity compensates to the real time monitoring of blower electric current and the control to electric current.
First way is by precision drift in wind pressure sensing module lifetime and pressure sensor location consistency, accuracy factor
It influences, the case where often there is wind pressure fault misdescription or do not report,
And the second way is difficult to realize good matching properties in system full load section, wind pressure fault misdescription often occurs
Or the case where not reporting；
As it can be seen that existing control mode will cause the bad usage experience of user there are the appearance of problem, and deeper
When secondary defect occurs, system down may be made to cause the generation of safety accident.
Summary of the invention
In view of this, the main purpose of the present invention is to provide a kind of controlling parties that gas heater air pressure system is adaptive
Method.
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 that gas heater air pressure system is adaptive, this method are as follows: according to
The complete machine rated load and formula P=R/M × K of gas heater determine maximum virtual pressure value P max and minimum virtual pressure value
Pmin and maximum virtual pressure value P max and the corresponding blower maximum (top) speed FH of minimum virtual pressure value P min, blower
Minimum speed FL；Curve is determined according to maximum virtual pressure value P max, minimum virtual pressure value P min and proportioning valve electric current；
Actual pressure value P is determined according to the curve and formulaIt is practicalWith target pressure value PTarget, the actual pressure value PIt is practicalWith target pressure
Force value PTargetDifference as control deviation Err；0 realization adaptive equalization is leveled off to by adjusting the control deviation Err.
It is described that actual pressure value P is determined according to the curve and formula in above schemeIt is practicalWith target pressure value PTargetIt
Afterwards, this method further include: compare actual pressure value PIt is practicalWith target pressure value PTargetSize relation, when the actual pressure value
PIt is practicalLess than or equal to target pressure value PTargetWhen with the difference of deviation threshold, without realizing adaptive equalization；When the actual pressure
Value PIt is practicalGreater than target pressure value PTargetWhen with the difference of deviation threshold, control deviation Err is determined to carry out adaptive equalization.
In above scheme, this method further include: in approximate procedure, the actual pressure value PIt is practicalWith target pressure value PTarget
Difference as differential process pressure value Δ PMoment, as the Δ PMoment reachesAlarm threshold value Δ Pmax is limited, and current rotation speed of fan reaches
When maximum (top) speed value Rmax, gas heater is alarmed.
In above scheme, the actual pressure value PIt is practicalSampling process are as follows: each fixed cycle carries out a sampled pressure
Value PSampling: PSampling=R/M × K integrates the pressure increase value every time after sampling, acquires recently at least 5 heat pressure and increases
The average value T added；Determine the pressure integrated value P at least five sampling periodIncrease, PIncreaseThe each sampling flow of=T/, finally, root
According to the PSamplingWith pressure integrated value PIncreaseDetermine actual pressure value PIt is practical, PIt is practical=PSampling+PIncrease。
It is described according to maximum virtual pressure value P max, minimum virtual pressure value P min and proportioning valve electricity in above scheme
It flows and determines curve, specifically: using maximum virtual pressure value P max, minimum virtual pressure value P min as the starting point of curve and terminal,
Linear distribution is carried out in conjunction with each load point Q of full load section.
It is described to level off to 0 realization adaptive equalization by adjusting the control deviation Err in above scheme, specifically: it adjusts
Whole actual pressure value PIt is practicalRotation speed of fan and blower current ratio R/M make control deviation Err level off to 0.
In above scheme, this method further include: after the delay set time, the actual pressure value PIt is practicalAnd target pressure value
PTargetDifference as control deviation Err.
Compared with prior art, the present invention guarantee under different use conditions systematic air flow can adaptive adjusting meet it is whole
Machine performance requirement, at the same meet under severe maximum conditions can starting protection function in time, avoid damage built-in system or make
Occur at the problem of safety accident.
Detailed description of the invention
Fig. 1 provides a kind of flow chart of control method that gas heater air pressure system is adaptive for the embodiment of the present invention；
Fig. 2 provides the curve in a kind of control method that gas heater air pressure system is adaptive for the embodiment of the present invention and shows
It is intended to；
Fig. 3 provides control deviation in a kind of control method that gas heater air pressure system is adaptive for the embodiment of the present invention
The adjustment logic chart of Err.
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 that gas heater air pressure system is adaptive, as shown in Figure 1, the party
Method is realized by following steps:
Step 101: maximum virtual pressure value is determined according to the complete machine rated load of gas heater and formula P=R/M × K
Pmax and minimum virtual pressure value P min and maximum virtual pressure value P max and minimum virtual pressure value P min are corresponding
Blower maximum (top) speed FH, blower minimum speed FL；
Specifically, according to complete machine rated load and minimum load requirement, secondary pressure parameter PH (maximum secondary pressure), PL are set
(minimum secondary pressure).
For meet standard (CO≤600ppm after conversion) and system design margin requirement, set 3 meter of 3 curved cigarette of complete machine
Properties of smoker index (CO ≈ 400ppm after conversion), according to the R/M ratio actually reflected and passes through adjusted coefficient K when pipe is installed
(constant) input exports maximum virtual pressure value P max (R/M × K).
The virtual pressure value P obtained in normal conditionsTarget=Pmax, while obtaining blower maximum (top) speed FH.
Referring especially to value (CO, O2 and exhaust gas temperature, dew-point temperature), R is obtainedTarget/MTarget× K=Pmin, while obtaining wind
Machine maximum (top) speed FL.
Step 102: being determined according to maximum virtual pressure value P max, minimum virtual pressure value P min and proportioning valve electric current
Curve；
Specifically, as shown in Fig. 2, using maximum virtual pressure value P max, minimum virtual pressure value P min as the starting point of curve
And terminal, linear distribution is carried out in conjunction with each load point Q of full load section.
Step 103: actual pressure value P is determined according to the curve and formulaIt is practicalWith target pressure value PTarget, the practical pressure
Force value PIt is practicalWith target pressure value PTargetDifference as control deviation Err；
Specifically, according to formula P=R/M × K, air quantity Adaptive Compensation Control scheme can see the control of pressure conservation as
Principle, the process pressure value of reality output need the pressure value on continuous approximation theory linearity curve, PIt is practical≈PIt is theoretical。
Compare actual pressure value PIt is practicalWith target pressure value PTargetSize relation, as the actual pressure value PIt is practicalLess than etc.
In target pressure value PTargetWhen with the difference of deviation threshold, without realizing adaptive equalization；As the actual pressure value PIt is practicalIt is greater than
Target pressure value PTargetWhen with the difference of deviation threshold, control deviation Err is determined to carry out adaptive equalization.
The actual pressure value PIt is practicalSampling process are as follows: each fixed cycle carries out a sampled pressure value PSampling: PSampling
=R/M × K integrates the pressure increase value every time after sampling, acquires recently being averaged at least 5 heat pressure increasies
Value T；Determine the pressure integrated value P at least five sampling periodIncrease, PIncreaseThe each sampling flow of=T/, finally, according to described
PSamplingWith pressure integrated value PIncreaseDetermine actual pressure value PIt is practical, PIt is practical=PSampling+PIncrease。
Further, it is delayed after the set time, the actual pressure value PIt is practicalWith target pressure value PTargetDifference as control
Deviation Err.
Air quantity adaptive equalization is with certain rear stickiness, therefore the present invention increases deviation threshold and delay, can be improved
The adaptive range of system.
Such as deviation threshold can use ± 5Pa, delay can use 10s.
Step 104: leveling off to 0 realization adaptive equalization by adjusting the control deviation Err.
Specifically, actual pressure value P is adjustedIt is practicalRotation speed of fan and blower current ratio R/M control deviation Err is become
It is bordering on 0.
As shown in figure 3, P=R/M × K is known quantity, P can be obtained by linear ratio relationTarget, by control deviation Err
=PTarget-PIt is practicalCarrying out PID arithmetic approaches Err by the adjustment constantly to process rotation speed of fan and blower current ratio R/M
In 0.
The present invention only focuses on air quantity input, and the output of R/M × K controls input by the difference of output, forms closed loop control
System.
Step 105: in approximate procedure, the actual pressure value PIt is practicalWith target pressure value PTargetDifference as differential process pressure
It is worth Δ PMoment, as the Δ PMoment reachesAlarm threshold value Δ Pmax is limited, and when current rotation speed of fan reaches maximum (top) speed value Rmax,
Gas heater is alarmed.
The foregoing is only a preferred embodiment of the present invention, is not intended to limit the scope of the present invention.
Claims (7)
1. a kind of control method that gas heater air pressure system is adaptive, which is characterized in that this method are as follows: according to gas and hot water
The complete machine rated load and formula P=R/M × K of device determine maximum virtual pressure value P max and minimum virtual pressure value P min, with
And the corresponding blower maximum (top) speed FH of maximum virtual pressure value P max and minimum virtually pressure value P min, blower minimum speed
FL；Curve is determined according to maximum virtual pressure value P max, minimum virtual pressure value P min and proportioning valve electric current；According to described
Curve and formula determine actual pressure value PIt is practicalWith target pressure value PTarget, the actual pressure value PIt is practicalWith target pressure value PTargetIt
Difference is used as control deviation Err；0 realization adaptive equalization is leveled off to by adjusting the control deviation Err.
2. the adaptive control method of gas heater air pressure system according to claim 1, which is characterized in that described
Actual pressure value P is determined according to the curve and formulaIt is practicalWith target pressure value PTargetLater, this method further include: relatively practical pressure
Force value PIt is practicalWith target pressure value PTargetSize relation, as the actual pressure value PIt is practicalLess than or equal to target pressure value PTargetWith it is inclined
When the difference of poor threshold value, without realizing adaptive equalization；As the actual pressure value PIt is practicalGreater than target pressure value PTargetAnd deviation
When the difference of threshold value, control deviation Err is determined to carry out adaptive equalization.
3. the adaptive control method of gas heater air pressure system according to claim 1 or 2, which is characterized in that should
Method further include: in approximate procedure, the actual pressure value PIt is practicalWith target pressure value PTargetDifference as differential process pressure value Δ
PMoment, as the Δ PMoment reachesAlarm threshold value Δ Pmax is limited, and when current rotation speed of fan reaches maximum (top) speed value Rmax, combustion gas
Water heater is alarmed.
4. the adaptive control method of gas heater air pressure system according to claim 3, which is characterized in that the reality
Border pressure value PIt is practicalSampling process are as follows: each fixed cycle carries out a sampled pressure value PSampling: PSampling=R/M × K, is adopted every time
After sample, which is integrated, acquires the average value T of at least 5 times heat pressure increasies recently；Determine at least five
Pressure integrated value P in sampling periodIncrease, PIncreaseThe each sampling flow of=T/, finally, according to the PSamplingWith pressure integrated value PIncrease
Determine actual pressure value PIt is practical, PIt is practical=PSampling+PIncrease。
5. the adaptive control method of gas heater air pressure system according to claim 4, which is characterized in that described
Curve is determined according to maximum virtual pressure value P max, minimum virtual pressure value P min and proportioning valve electric current, specifically: with maximum
Virtual pressure value P max, the starting point and terminal that minimum virtual pressure value P min is curve, in conjunction with full load section each load point Q into
Row linear distribution.
6. the adaptive control method of gas heater air pressure system according to claim 5, which is characterized in that described logical
It crosses and adjusts the control deviation Err and level off to 0 realization adaptive equalization, specifically:
Adjust actual pressure value PIt is practicalRotation speed of fan and blower current ratio R/M make control deviation Err level off to 0.
7. the adaptive control method of gas heater air pressure system according to claim 6, which is characterized in that this method
Further include: after the delay set time, the actual pressure value PIt is practicalWith target pressure value PTargetDifference as control deviation Err.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201811028095.2A CN110207387A (en) | 2018-09-04 | 2018-09-04 | Self-adaptive control method for air pressure system of gas water heater |
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| CN201811028095.2A CN110207387A (en) | 2018-09-04 | 2018-09-04 | Self-adaptive control method for air pressure system of gas water heater |
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Cited By (2)
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| CN112524636A (en) * | 2020-11-30 | 2021-03-19 | 芜湖美的厨卫电器制造有限公司 | Control method and device of gas water heater, gas water heater and storage medium |
| CN115200227A (en) * | 2022-08-26 | 2022-10-18 | 芜湖美的智能厨电制造有限公司 | Gas water heater control method and device, gas water heater and storage medium |
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Application publication date: 20190906 |
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