EP3751200A1 - Method for controlling a heater powered by combustion gas - Google Patents
Method for controlling a heater powered by combustion gas Download PDFInfo
- Publication number
- EP3751200A1 EP3751200A1 EP20172720.3A EP20172720A EP3751200A1 EP 3751200 A1 EP3751200 A1 EP 3751200A1 EP 20172720 A EP20172720 A EP 20172720A EP 3751200 A1 EP3751200 A1 EP 3751200A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- burner
- gas
- output
- gas actuator
- actuator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 31
- 239000000567 combustion gas Substances 0.000 title 1
- 238000000691 measurement method Methods 0.000 claims abstract description 11
- 239000000446 fuel Substances 0.000 claims abstract description 8
- 230000001105 regulatory effect Effects 0.000 claims abstract description 8
- 239000007789 gas Substances 0.000 claims description 91
- 239000002737 fuel gas Substances 0.000 claims description 28
- 239000000203 mixture Substances 0.000 claims description 10
- 238000005259 measurement Methods 0.000 claims description 6
- 239000003570 air Substances 0.000 description 28
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 10
- 239000007788 liquid Substances 0.000 description 5
- 239000003345 natural gas Substances 0.000 description 5
- 238000002485 combustion reaction Methods 0.000 description 3
- GVGLGOZIDCSQPN-PVHGPHFFSA-N Heroin Chemical compound O([C@H]1[C@H](C=C[C@H]23)OC(C)=O)C4=C5[C@@]12CCN(C)[C@@H]3CC5=CC=C4OC(C)=O GVGLGOZIDCSQPN-PVHGPHFFSA-N 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- 239000012080 ambient air Substances 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N5/00—Systems for controlling combustion
- F23N5/02—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium
- F23N5/12—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using ionisation-sensitive elements, i.e. flame rods
- F23N5/123—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using ionisation-sensitive elements, i.e. flame rods using electronic 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
- F23N1/022—Regulating fuel supply conjointly with air supply using electronic means
Definitions
- the invention relates to a method for regulating a fuel gas-operated heater.
- Another problem with the control method is that different types of gas, e.g. Natural gas or liquid gas, as well as gas qualities, are used.
- the parameters of the control process must be adapted to the type of gas or gas quality, as otherwise the combustion will be unclean.
- Alternative control methods are based on an electronic mixture control using thermal gas mass sensors to record the fuel gas properties via the thermal conductivity of the fuel gas.
- the air requirement is determined from the type of fuel gas using a reference table and the air volume is calculated and adjusted according to the measured gas volume and the determined air requirement.
- the method requires that all input variables required for the mixture control must be measured and monitored.
- the invention is based on the object of providing a method, which is independent of the type of fuel gas, for regulating a fuel gas-operated heating device over a broad modulation range, which method requires less monitoring effort and hardware use than the known methods. In particular, it should be possible to dispense with the use of a fuel gas mass sensor.
- a method for regulating a fuel gas-operated heater using an ionization measurement method of a burner flame of the heater in which a fuel gas volume flow controlled by a gas actuator and an air volume flow supplied by a fan are mixed to form a fuel gas-air mixture and with an air ratio ⁇ based on a desired burner output be fed to a burner of the heater.
- the air ratio ⁇ is monitored by means of the ionization measurement method of the burner flame of the burner.
- a gas control characteristic curve of the gas control element is recorded in the laboratory and stored in a control unit.
- the gas actuator control characteristic here determines a percentage flow rate through the gas actuator depending on the opening position points of the gas actuator, the percentage flow rate through the gas actuator representing a burner output of the burner.
- the burner output of the burner is regulated in a first output range based on the results of the ionization measurement process and in a second output range based on the gas actuator control characteristic, with certain burner outputs being assigned to certain opening positions of the gas actuator during the regulation of the heater in the first output range.
- the ratio of the amount of fuel gas to the amount of air is kept constant in the second power range.
- the first power range preferably corresponds to a control range in which the burner flame supplies the ionization measurement method with sufficiently precise signal data that the control can take place as a pure ionization control. This is the case in particular with a sufficiently large burner flame in which the ionization electrode used for the ionization measurement method supplies exact signals to the control device.
- the second performance area is in particular a range of low burner output, for example below 50% of the maximum output.
- the gas actuator control characteristic is predefined in the laboratory.
- the gas actuator control characteristic includes any number of subdivision points that correspond to the positions of the gas actuator for fixed burner output steps. This also defines the relationship between the amount of fuel gas and the respective opening position of the gas actuator.
- the heating output of the heater results in different working areas in the characteristic curve, depending on the type of fuel gas due to the different density of the fuel gas, the different energy content and air requirement.
- the gas quality changes e.g. B. from liquid gas to natural gas would change due to the changed density of the volume flow.
- the energy content and thus the amount of fuel gas required to achieve the desired burner output would also be different.
- the absolute burner output changes, but not the ratio of the individual opening positions of the gas actuator to one another. If, for example, the actual burner output is halved in one opening position, then the burner output is halved in all other output points along the control characteristic.
- a gas actuator control characteristic is thus used which determines a percentage flow rate through the gas actuator as a function of the opening position points of the gas actuator.
- the method provides that the specific outputs of the burner are assigned to the specific opening position points of the gas actuator in that, during the regulation of the burner output of the burner in the first power range, an air quantity supplied to the burner and a required amount of air are measured at any opening position Fuel gas quantity is supplied via the gas actuator until a predetermined air ratio ⁇ is reached.
- the required burner output is changed by adapting the air quantity, with the control device setting corresponding opening positions of the gas actuator from the gas control characteristic curve of the adjusted burner output.
- the disclosed method makes use of the fact that the burner output is known during the regulation in the first regulation range using the ionization measurement method, and from this the opening position points of the gas actuator can be predetermined for all other desired burner outputs.
- the air volume flow for generating the fuel gas-air mixture is measured during the control in the first control range using the ionization measurement method in any opening position of the gas actuator.
- the control unit regulates the amount of fuel gas required for clean combustion of a predefined air ratio via the ionization control.
- the matching opening position of the gas actuator is assigned to the corresponding air volume flow in the control unit.
- the appropriate fuel gas volume must also be adjusted as a percentage, i.e. also 10% less or more. This adaptation takes place via a change in the opening position of the gas actuator controlled by the control unit.
- a further development of the method provides that the gas actuator control characteristic is calibrated at time intervals to compensate for a characteristic drift.
- a characteristic drift is characterized by a change in the amount of fuel gas that occurs over the service life at certain opening positions of the gas actuator.
- the individual opening position points no longer correspond to the corresponding fuel gas volume flows, but the percentage power differences between the individual opening position points remain constant because the flow characteristics through the gas actuator do not change due to the characteristic drift. This means that the characteristic curve itself does not change, only the position within the working area.
- the characteristic drift can be equalized by calibration.
- the calibration takes place during the regulation of the burner output of the burner in the first output range based on the results of the ionization measurement process, in that two output points of the burner output are controlled via the control unit and the output values of the burner output stored in the gas actuator control characteristic are compared with the actual output values of the burner output the gas actuator control characteristic is corrected to the actual output values of the burner output.
- An advantageous embodiment of the method further provides that the gas actuator is controlled by a stepping motor and a defined number of steps of the stepping motor determines a defined change in the opening position points of the gas actuator.
- FIG 1 is a schematic structure of a heater 100 for carrying out the control method with a modulating premix blower 5, which sucks in ambient air a and mixes it with fuel gas.
- the fuel gas is fed to the premix blower 5 at the inlet 4 via a gas line in which a gas safety valve 1 and a gas valve 2, which can be controlled, for example, via a motor M, are arranged, which forms the gas actuator.
- the gas inlet pressure d is adapted to the gas control pressure c.
- the mixture After mixing with ambient air, the mixture has the mixture pressure b.
- an optional non-return flap 6 is provided at the blower outlet.
- the mixture then has the burner pressure e. This is followed by the burner 28 with the ionization electrode 7 arranged in the burner flame.
- the heat exchanger 18 is arranged around the burner 28. Continued in the flow direction, the exhaust system follows with the exhaust flap 8. The exhaust gas pressure f prevails in the exhaust system. The regulation of the amount of fuel gas as well as the fan speed and consequently the air ratio takes place via the control unit 9 in which the regulation characteristics are stored.
- Figure 2 shows the gas actuator control characteristic used for the method with opening position points p1, p2, p3-p9, which represent a defined opening position of the gas valve 2 and thus a fixed percentage flow rate F of fuel gas.
- the burner output of the burner 28 is regulated in the output range in which the ionization control is sufficiently exact, based on the results of the ionization measurement method using the ionization electrode 7.
- the gas actuator control characteristic 82 of the gas valve 2 is recorded in the laboratory and stored in the control unit 9. It is used for the method in a power range in which the ionization control based on the ionization measurement via the ionization electrode 7 is not sufficiently accurate.
- specific opening position points p of the gas actuator are assigned specific powers of the burner 28.
- the ratio of the amount of fuel gas to the amount of air remains constant in the control using the gas actuator control characteristic line 82.
- Certain outputs of the burner 28 are assigned to the opening position points p of the gas valve 2 in that during the control of the burner output of the burner 28 in the output range of the ionization control at any opening position point p of the air volume supplied to the burner 28, the correspondingly required fuel gas volume is supplied via the gas valve 2 until the desired air ratio ⁇ has been reached.
- the required burner output is changed by adapting the amount of air, with opening position points p of the gas valve 2 corresponding to the adjusted burner output being set via the control unit 9 from the gas actuator control characteristic 82.
- FIGs 3 and 4th show the gas actuator control characteristic Figure 2 for two different types of fuel gas, whereby Figure 3 for example natural gas, Figure 4 Corresponds to liquid gas.
- a gas volume flow for, for example, 10 kW burner output is achieved in the opening position point p8, which corresponds to 80% of the control characteristic.
- the control activates position p4, which corresponds to 40% of the control characteristic.
- the fuel gas changes from natural gas to liquid gas, the same burner output results in a burner output of 10kW at an open position point p6, half the burner output at p3, as in Figure 4 shown.
- the control device 9 can thus adapt or interpolate the burner output to the corresponding air flow from each burner output established and verified once during the ionization control by adjusting the opening position points p of the gas valve 2.
- FIG Figure 5 shows a characteristic drift of the gas actuator control characteristic 82 over the life of the heater 100.
- a stepper motor M is preferably used to control the gas valve 2.
- two power points with, for example, opening position points p9 and p6, which determine 90% and 60% of the burner output of burner 28, are controlled in the area of the ionization control.
- a difference in the step change of the stepping motor M as well as a possible change in power is determined, which in Figure 6 are shown by way of example as ⁇ 9 and ⁇ 6.
- a new characteristic curve position is determined from the shifts of the two performance points and all new opening position points p are corrected.
- Figure 6 shows that with an exemplary power of 10% from the step difference of the stepping motor M between the old power point 60% to 10% stored in the control unit 9, a new step difference, identified as ⁇ 1-6, is calculated.
- the calibrated characteristic then replaces the previous characteristic in control unit 9.
Abstract
Die Erfindung betrifft ein gasartenunabhängiges Verfahren zur Regelung eines brenngasbetriebenen Heizgerätes unter Nutzung eines lonisationsmessverfahrens einer Brennerflamme des Heizgerätes und einer eine Gasstellglied-Regelungskennlinie des Gasstellglieds.The invention relates to a gas type-independent method for regulating a fuel gas-operated heater using an ionization measurement method of a burner flame of the heater and a gas control characteristic curve of the gas control element.
Description
Die Erfindung betrifft ein Verfahren zur Regelung eines brenngasbetriebenen Heizgerätes.The invention relates to a method for regulating a fuel gas-operated heater.
Gattungsbildende Verfahren sind aus dem Stand der Technik bekannt, beispielsweise aus der Offenbarung gemäß der Druckschrift
Eine Problematik der Regelungsverfahren liegt zudem darin, dass für die Verbrennung unterschiedliche Gasarten, z.B. Erdgas oder Flüssiggas, sowie Gasqualitäten zum Einsatz kommen. Die Parameter des Regelungsverfahrens müssen auf die Gasart bzw. Gasqualität angepasst werden, da die Verbrennung andernfalls unsauber abläuft.Another problem with the control method is that different types of gas, e.g. Natural gas or liquid gas, as well as gas qualities, are used. The parameters of the control process must be adapted to the type of gas or gas quality, as otherwise the combustion will be unclean.
Alternative Regelungsverfahren basieren auf einer elektronischen Gemischregelung unter Nutzung von thermischen Gasmassensensoren zur Erfassung der Brenngaseigenschaften über die thermische Leitfähigkeit des Brenngases. Aus der Brenngasart wird der Luftbedarf über eine Referenztabelle ermittelt und die Luftmenge entsprechend der gemessenen Gasmenge und dem ermittelten Luftbedarf errechnet und eingeregelt. Das Verfahren erfordert jedoch, dass alle für die Gemischregelung benötigten Eingangsgrößen gemessen und überwacht werden müssen.Alternative control methods are based on an electronic mixture control using thermal gas mass sensors to record the fuel gas properties via the thermal conductivity of the fuel gas. The air requirement is determined from the type of fuel gas using a reference table and the air volume is calculated and adjusted according to the measured gas volume and the determined air requirement. However, the method requires that all input variables required for the mixture control must be measured and monitored.
Der Erfindung liegt die Aufgabe zugrunde, ein brenngasartenunabhängiges Verfahren zur Regelung eines brenngasbetriebenen Heizgerätes über einen breiten Modulationsbereich bereitzustellen, das einen gegenüber den bekannten Verfahren geringeren Überwachungsaufwand und Hardwareeinsatz erfordert. Insbesondere soll auf die Verwendung eines Brenngasmassensensors verzichtet werden können.The invention is based on the object of providing a method, which is independent of the type of fuel gas, for regulating a fuel gas-operated heating device over a broad modulation range, which method requires less monitoring effort and hardware use than the known methods. In particular, it should be possible to dispense with the use of a fuel gas mass sensor.
Diese Aufgabe wird durch die Merkmalskombination gemäß Patentanspruch 1 gelöst.This object is achieved by the combination of features according to
Erfindungsgemäß wird ein Verfahren zur Regelung eines brenngasbetriebenen Heizgerätes unter Nutzung eines lonisationsmessverfahrens einer Brennerflamme des Heizgerätes vorgeschlagen, bei dem ein über ein Gasstellglied gesteuerter Brenngasvolumenstrom und ein über ein Gebläse gelieferter Luftvolumenstrom zu einem Brenngas-Luftgemisch gemischt und mit einer auf einer gewünschten Brennerleistung basierenden Luftzahl λ einem Brenner des Heizgerätes zugeführt werden. Die Luftzahl λ wird mittels des lonisationsmessverfahrens der Brennerflamme des Brenners überwacht. Zudem wird eine Gasstellglied-Regelungskennlinie des Gasstellglieds labortechnisch erfasst und in einem Steuergerät hinterlegt. Die Gasstellglied-Regelungskennlinie bestimmt hierbei eine prozentuale Durchflussmenge durch das Gasstellglied in Abhängigkeit von Öffnungsstellungspunkten des Gasstellglieds, wobei die prozentuale Durchflussmenge durch das Gasstellglied eine Brennerleistung des Brenners repräsentiert. Die Regelung der Brennerleistung des Brenners erfolgt in einem ersten Leistungsbereich basierend auf den Ergebnissen des lonisationsmessverfahrens und in einem zweiten Leistungsbereich basierend auf der Gasstellglied-Regelungskennlinie, wobei während der Regelung des Heizgerätes in dem ersten Leistungsbereich bestimmten Öffnungsstellungspunkten des Gasstellglieds bestimmte Leistungen des Brenners zugeordnet werden. Das Verhältnis der Brenngasmenge zur Luftmenge wird dabei im zweiten Leistungsbereich konstant gehalten.According to the invention, a method for regulating a fuel gas-operated heater using an ionization measurement method of a burner flame of the heater is proposed, in which a fuel gas volume flow controlled by a gas actuator and an air volume flow supplied by a fan are mixed to form a fuel gas-air mixture and with an air ratio λ based on a desired burner output be fed to a burner of the heater. The air ratio λ is monitored by means of the ionization measurement method of the burner flame of the burner. In addition, a gas control characteristic curve of the gas control element is recorded in the laboratory and stored in a control unit. The gas actuator control characteristic here determines a percentage flow rate through the gas actuator depending on the opening position points of the gas actuator, the percentage flow rate through the gas actuator representing a burner output of the burner. The burner output of the burner is regulated in a first output range based on the results of the ionization measurement process and in a second output range based on the gas actuator control characteristic, with certain burner outputs being assigned to certain opening positions of the gas actuator during the regulation of the heater in the first output range. The ratio of the amount of fuel gas to the amount of air is kept constant in the second power range.
Der erste Leistungsbereich entspricht vorzugsweise einem Regelbereich, in dem die Brennerflamme dem lonisationsmessverfahren ausreichend genaue Signaldaten liefert, dass die Regelung als reine Ionisationsregelung erfolgen kann. Die ist insbesondere bei ausreichend großer Brennerflamme der Fall, bei der die für das lonisationsmessverfahren verwendete Ionisationselektrode exakte Signale an das Steuergerät liefert. Der zweite Leistungsbereich ist insbesondere ein Bereich geringer Brennerleistung, beispielsweise unterhalb von 50% der Maximalleistung.The first power range preferably corresponds to a control range in which the burner flame supplies the ionization measurement method with sufficiently precise signal data that the control can take place as a pure ionization control. This is the case in particular with a sufficiently large burner flame in which the ionization electrode used for the ionization measurement method supplies exact signals to the control device. The second performance area is in particular a range of low burner output, for example below 50% of the maximum output.
Die Gasstellglied-Regelungskennlinie wird labortechnisch vordefiniert. Die Gasstellglied-Regelungskennlinie umfasst beliebig viele Untergliederungspunkte, die den Positionen des Gasstellglieds bei festen Brennerleistungsschritten entspricht. Damit ist auch festgelegt, in welchem Verhältnis die Brenngasmenge zu dem jeweiligen Öffnungsstellungspunkt des Gasstellglieds steht. Bei einer gleichen Brennerleistung, d.h. Wärmeleistung des Heizgerätes ergeben sich je nach Brenngasart aufgrund der unterschiedlichen Dichte des Brenngases, des unterschiedlichen Energieinhaltes und Luftbedarfes unterschiedliche Arbeitsbereiche im Kennlinienfeld. Bei einer Änderung der Gasbeschaffenheit, z. B. von Flüssiggas auf Erdgas würde sich aufgrund der geänderten Dichte der Volumenstrom ändern. Auch der Energieinhalt und somit die erforderliche Brenngasmenge zu Erreichung der gewünschten Brennerleistung wären unterschiedlich. Da diese Zusammenhänge aber für jede der angesteuerten Position gelten, ändert sich zwar die absolute Brennerleistung, nicht aber das Leistungsverhältnis der einzelnen Öffnungsstellungspunkte des Gasstellglieds zueinander. Wenn sich somit die tatsächliche Brennerleistung in einem Öffnungsstellungspunkt beispielsweise halbiert, dann halbiert sich die Brennerleistung auch auf in allen anderen Leistungspunkten entlang der Regelungskennlinie. Erfindungsgemäß wird somit eine Gasstellglied-Regelungskennlinie verwendet, welche eine prozentuale Durchflussmenge durch das Gasstellglied in Abhängigkeit von Öffnungsstellungspunkten des Gasstellglieds bestimmt.The gas actuator control characteristic is predefined in the laboratory. The gas actuator control characteristic includes any number of subdivision points that correspond to the positions of the gas actuator for fixed burner output steps. This also defines the relationship between the amount of fuel gas and the respective opening position of the gas actuator. With the same burner output, i.e. The heating output of the heater results in different working areas in the characteristic curve, depending on the type of fuel gas due to the different density of the fuel gas, the different energy content and air requirement. When the gas quality changes, e.g. B. from liquid gas to natural gas would change due to the changed density of the volume flow. The energy content and thus the amount of fuel gas required to achieve the desired burner output would also be different. Since these relationships apply to each of the activated positions, the absolute burner output changes, but not the ratio of the individual opening positions of the gas actuator to one another. If, for example, the actual burner output is halved in one opening position, then the burner output is halved in all other output points along the control characteristic. According to the invention, a gas actuator control characteristic is thus used which determines a percentage flow rate through the gas actuator as a function of the opening position points of the gas actuator.
Das Verfahren sieht vor, dass den bestimmten Öffnungsstellungspunkten des Gasstellglieds die bestimmten Leistungen des Brenners dadurch zugeordnet werden, dass während der Regelung der Brennerleistung des Brenners in dem ersten Leistungsbereich bei einem beliebigen Öffnungsstellungspunkt eine dem Brenner zugeführte Luftmenge gemessen und eine erforderliche Brenngasmenge über das Gasstellglied zugeführt wird, bis eine vorbestimmte Luftzahl λ erreicht ist. Ferner erfolgt eine Änderung der benötigten Brennerleistung durch eine Anpassung der Luftmenge, wobei über das Steuergerät aus der Gasstellglied-Regelungskennlinie der angepassten Brennerleistung korrespondierende Öffnungsstellungspunkte des Gasstellglieds eingestellt werden.The method provides that the specific outputs of the burner are assigned to the specific opening position points of the gas actuator in that, during the regulation of the burner output of the burner in the first power range, an air quantity supplied to the burner and a required amount of air are measured at any opening position Fuel gas quantity is supplied via the gas actuator until a predetermined air ratio λ is reached. In addition, the required burner output is changed by adapting the air quantity, with the control device setting corresponding opening positions of the gas actuator from the gas control characteristic curve of the adjusted burner output.
Das offenbarte Verfahren nutzt, dass die Brennerleistung während der Regelung im ersten Regelungsbereich unter Nutzung des lonisationsmessverfahrens bekannt ist und daraus für alle anderen gewünschten Brennerleistungen die Öffnungsstellungspunkte des Gasstellglieds vorherbestimmt werden können. Dazu wird während der Regelung im ersten Regelungsbereich unter Nutzung des lonisationsmessverfahrens in einem beliebigen Öffnungsstellungspunkt des Gasstellglieds der Luftvolumenstrom zur Erzeugung des Brenngas-Luftgemisches gemessen. Über die Ionisationsregelung wird über das Steuergerät die für eine saubere Verbrennung einer vordefinierten Luftzahl erforderliche Brenngasmenge dazu geregelt. Der dazu passende Öffnungsstellungspunkt des Gasstellglieds wird im Steuergerät dem entsprechenden Luftvolumenstrom zugeordnet. Sinkt oder steigt der Wärmebedarf, wird über das Steuergerät über das Gebläse eine neue Luftmenge eingestellt, beispielsweise 10% weniger oder mehr, dann muss die dazu passende Brenngasmenge ebenfalls prozentual angepasst werden, d.h. ebenfalls 10% weniger oder mehr. Diese Anpassung erfolgt über eine Änderung des Öffnungsstellungspunktes des Gasstellglieds gesteuert durch das Steuergerät.The disclosed method makes use of the fact that the burner output is known during the regulation in the first regulation range using the ionization measurement method, and from this the opening position points of the gas actuator can be predetermined for all other desired burner outputs. For this purpose, the air volume flow for generating the fuel gas-air mixture is measured during the control in the first control range using the ionization measurement method in any opening position of the gas actuator. The control unit regulates the amount of fuel gas required for clean combustion of a predefined air ratio via the ionization control. The matching opening position of the gas actuator is assigned to the corresponding air volume flow in the control unit. If the heat demand falls or increases, if a new air volume is set via the control unit via the fan, for example 10% less or more, then the appropriate fuel gas volume must also be adjusted as a percentage, i.e. also 10% less or more. This adaptation takes place via a change in the opening position of the gas actuator controlled by the control unit.
Eine Weiterbildung des Verfahrens sieht vor, dass die Gasstellglied-Regelungskennlinie in zeitlichen Abständen zum Ausgleich eines Kennliniendrifts kalibriert wird. Ein Kennliniendrift ist durch eine sich über die Lebensdauer ergebende Änderung der Brenngasmenge bei bestimmten Öffnungsstellungspunkten des Gasstellglieds gekennzeichnet.A further development of the method provides that the gas actuator control characteristic is calibrated at time intervals to compensate for a characteristic drift. A characteristic drift is characterized by a change in the amount of fuel gas that occurs over the service life at certain opening positions of the gas actuator.
Bei einer Kennliniendrift stimmen zwar die einzelnen Öffnungsstellungspunkte mit den entsprechenden Brenngasvolumenströmen nicht mehr überein, die prozentualen Leistungsdifferenzen zwischen den einzelnen Öffnungsstellungspunkte bleiben jedoch konstant, da sich die Durchflusscharakteristik durch das Gasstellglied durch den Kennliniendrift nicht verändert. Das heißt, es verändert sich nicht die Kennlinie selbst, sondern nur die Lage innerhalb des Arbeitsbereiches. Durch eine Kalibrierung kann der Kennliniendrift egalisiert werden.In the case of a characteristic drift, the individual opening position points no longer correspond to the corresponding fuel gas volume flows, but the percentage power differences between the individual opening position points remain constant because the flow characteristics through the gas actuator do not change due to the characteristic drift. This means that the characteristic curve itself does not change, only the position within the working area. The characteristic drift can be equalized by calibration.
In einer Ausgestaltung erfolgt die Kalibrierung während der Regelung der Brennerleistung des Brenners im ersten Leistungsbereich basierend auf den Ergebnissen des lonisationsmessverfahrens, indem über das Steuergerät zwei Leistungspunkte der Brennerleistung angesteuert werden und die der Gasstellglied-Regelungskennlinie hinterlegten Leistungswerte der Brennerleistung mit den tatsächlichen Leistungswerten der Brennerleistung verglichen werden, wobei die Gasstellglied-Regelungskennlinie zu den tatsächlichen Leistungswerten der Brennerleistung korrigiert wird.In one embodiment, the calibration takes place during the regulation of the burner output of the burner in the first output range based on the results of the ionization measurement process, in that two output points of the burner output are controlled via the control unit and the output values of the burner output stored in the gas actuator control characteristic are compared with the actual output values of the burner output the gas actuator control characteristic is corrected to the actual output values of the burner output.
Eine vorteilhafte Ausgestaltung des Verfahrens sieht ferner vor, dass das Gasstellglied über einen Schrittmotor gesteuert wird und eine definierte Schrittzahl des Schrittmotors eine definierte Änderung der Öffnungsstellungspunkte des Gasstellglieds bestimmt.An advantageous embodiment of the method further provides that the gas actuator is controlled by a stepping motor and a defined number of steps of the stepping motor determines a defined change in the opening position points of the gas actuator.
Andere vorteilhafte Weiterbildungen der Erfindung sind in den Unteransprüchen gekennzeichnet bzw. werden nachstehend zusammen mit der Beschreibung der bevorzugten Ausführung der Erfindung anhand der Figuren näher dargestellt. Es zeigen:
- Fig. 1
- einen schematischen Aufbau eines Heizgerätes;
- Fig. 2
- eine im Verfahren genutzte Gasstellglied-Regelungskennlinie,
- Fig. 3
- die Gasstellglied-Regelungskennlinie aus
Figur 2 für Erdgas, - Fig. 4
- die Gasstellglied-Regelungskennlinie aus
Figur 2 für Flüssiggas, - Fig. 5
- einen Kennliniendrift der Gasstellglied-Regelungskennlinie aus
Figur 2 , und - Fig. 6
- eine Kalibrierung des Kennliniendrifts der GasstellgliedRegelungskennlinie aus
Figur 2 .
- Fig. 1
- a schematic structure of a heater;
- Fig. 2
- a gas actuator control characteristic used in the process,
- Fig. 3
- the gas actuator control characteristic
Figure 2 for natural gas, - Fig. 4
- the gas actuator control characteristic
Figure 2 for liquid gas, - Fig. 5
- a characteristic drift of the gas actuator control characteristic
Figure 2 , and - Fig. 6
- a calibration of the characteristic drift of the gas actuator control characteristic
Figure 2 .
In
Die Regelung der Brennerleistung des Brenners 28 erfolgt im Leistungsbereich, in dem die Ionisationsregelung ausreichend exakt ist, basierend auf den Ergebnissen des lonisationsmessverfahrens unter Nutzung der Ionisationselektrode 7. Die Gasstellglied-Regelungskennlinie 82 des Gasventils 2 wird labortechnisch erfasst und im Steuergerät 9 hinterlegt. Sie wird für das Verfahren in einem Leistungsbereich genutzt, in dem die Ionisationsregelung basierend auf der Ionisationsmessung über die Ionisationselektrode 7 nicht ausreichend genau ist. Dabei werden während der Regelung des Heizgerätes 100 in dem Leistungsbereich der Ionisationsregelung bestimmten Öffnungsstellungspunkten p des Gasstellglieds bestimmte Leistungen des Brenners 28 zugeordnet. Das Verhältnis der Brenngasmenge zur Luftmenge bleibt bei der Regelung unter Nutzung der Gasstellglied-Regelungskennlinie 82 konstant. Den Öffnungsstellungspunkten p des Gasventils 2 werden bestimmte Leistungen des Brenners 28 zugeordnet, indem während der Regelung der Brennerleistung des Brenners 28 im Leistungsbereich der Ionisationsregelung bei einem beliebigen Öffnungsstellungspunkt p der dem Brenner 28 zugeführte Luftmenge die entsprechend erforderliche Brenngasmenge über das Gasventil 2 zugeführt wird, bis die gewünschte Luftzahl λ erreicht ist. Die Änderung der benötigten Brennerleistung erfolgt durch die Anpassung der Luftmenge, wobei über das Steuergerät 9 aus der Gasstellglied-Regelungskennlinie 82 der angepassten Brennerleistung korrespondierende Öffnungsstellungspunkte p des Gasventils 2 eingestellt werden.The burner output of the
Die
In
Claims (6)
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DE102019114919.3A DE102019114919A1 (en) | 2019-06-04 | 2019-06-04 | Method for regulating a fuel gas operated heater |
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EP3751200A1 true EP3751200A1 (en) | 2020-12-16 |
EP3751200B1 EP3751200B1 (en) | 2021-11-03 |
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EP20172720.3A Active EP3751200B1 (en) | 2019-06-04 | 2020-05-04 | Method for controlling a heater powered by combustion gas |
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DE (1) | DE102019114919A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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IT202100032360A1 (en) | 2021-12-23 | 2023-06-23 | Sit Spa | METHOD AND APPARATUS FOR MONITORING AND CONTROL OF COMBUSTION IN FUEL GAS BURNERS |
Citations (4)
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---|---|---|---|---|
DE19831648A1 (en) * | 1998-07-15 | 2000-01-27 | Stiebel Eltron Gmbh & Co Kg | Process for automatic adaptation of control electronics of a gas heater device so that emissions are minimized by ensuring that the Lambda value is greater than one |
DE10025769A1 (en) * | 2000-05-12 | 2001-11-15 | Siemens Building Tech Ag | Control device for a burner |
WO2006000366A1 (en) | 2004-06-23 | 2006-01-05 | Ebm-Papst Landshut Gmbh | Method for regulating and controlling a firing apparatus, and firing apparatus |
DE102011102575A1 (en) * | 2011-05-26 | 2012-11-29 | Robert Bosch Gmbh | Method for calibrating air ratio regulation of burner with modulated burner output, involves adjusting blower to predetermined calibration speed, where calibration flow rate of air or fuel or fuel-air-mixture is determined |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102004030299A1 (en) * | 2004-06-23 | 2006-01-12 | Ebm-Papst Landshut Gmbh | Firing equipment for gas burners has means for determining value dependent on measured temperature and means for regulating generated temperature using characteristic line representing value range corresponding to ideal temperature |
-
2019
- 2019-06-04 DE DE102019114919.3A patent/DE102019114919A1/en active Pending
-
2020
- 2020-05-04 EP EP20172720.3A patent/EP3751200B1/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19831648A1 (en) * | 1998-07-15 | 2000-01-27 | Stiebel Eltron Gmbh & Co Kg | Process for automatic adaptation of control electronics of a gas heater device so that emissions are minimized by ensuring that the Lambda value is greater than one |
DE10025769A1 (en) * | 2000-05-12 | 2001-11-15 | Siemens Building Tech Ag | Control device for a burner |
WO2006000366A1 (en) | 2004-06-23 | 2006-01-05 | Ebm-Papst Landshut Gmbh | Method for regulating and controlling a firing apparatus, and firing apparatus |
DE102011102575A1 (en) * | 2011-05-26 | 2012-11-29 | Robert Bosch Gmbh | Method for calibrating air ratio regulation of burner with modulated burner output, involves adjusting blower to predetermined calibration speed, where calibration flow rate of air or fuel or fuel-air-mixture is determined |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT202100032360A1 (en) | 2021-12-23 | 2023-06-23 | Sit Spa | METHOD AND APPARATUS FOR MONITORING AND CONTROL OF COMBUSTION IN FUEL GAS BURNERS |
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EP3751200B1 (en) | 2021-11-03 |
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