Fuel quantity control and / or air quantity control

Abstract

This specification relates to open and / or closed-loop control units used in combustion devices, e.g., gas burners, in conjunction with combustion sensors. Combustion sensors in combustion devices include, for example, ionization electrodes and / or oxygen sensors. This specification specifically addresses the closed and / or open-loop control of combustion devices, particularly in the presence of hydrogen gas.

Description

background

[0001] This disclosure relates to control and / or regulation systems used in combustion devices, for example in gas burners, in conjunction with combustion sensors. Combustion sensors in combustion devices include, for example, ionization electrodes and / or oxygen sensors. This disclosure relates in particular to the regulation and / or control of combustion devices in the presence of hydrogen gas.

[0002] During the operation of a combustion device, its combustion power must be known and / or adjusted. For the combustion of hydrocarbons, pure hydrogen, or a mixture of both, the air supply and fuel supply must be adjusted relative to each other. This ensures the correct air-fuel ratio (λ).

[0003] Furthermore, external influences can affect the air-fuel ratio and / or the combustion output. Such external influences include, for example, the inlet pressure of the fuel, especially the fuel gas, and the fuel composition. Other examples of external influences are the ambient temperature, the ambient pressure, and changes in the intake air path and the exhaust path of the combustion device.

[0004] In addition to the sensors mentioned, sensors that monitor the flame for safety purposes can be integrated into the control of the combustion power and / or the air-fuel ratio of a combustion device. Currently, optical flame monitoring is used for the combustion of pure hydrogen in a combustion device. However, optical sensors for recording signals during combustion are complex and expensive.

[0005] A European patent application EP1154202A2 was filed on April 27, 2001, by Siemens Building Technology AG. The application was published on November 14, 2001. EP1154202A2 relates to a control device for a burner. EP1154202A2 claims priority from May 12, 2000. A granted European patent EP1154202B1 exists in relation to EP1154202A2.

[0006] EP1154202B2 distinguishes between fuel gases with low and high calorific values. Two characteristic curves are used to differentiate between the two fuel gases. Each of these curves represents a control signal for an actuator of the combustion device, based on a specific blower speed of the combustion device. Control signals corresponding to these characteristic curves are weighted to regulate the combustion device.

[0007] EP1154202B2 further claims the use of additional sensors for controlling the combustion device. These additional sensors influence the positions of actuators in the combustion device based on their sensor readings. As an example of measurement data obtained from these additional sensors, EP1154202B2 cites a change in boiler temperature.

[0008] Another patent application, DE102004055716A1, was filed on November 18, 2004, by EBM PAPST LANDSHUT GmbH. The application was published on January 12, 2006. DE102004055716A1 relates to a method for regulating and controlling a combustion system. DE102004055716A1 claims priority from June 23, 2004.

[0009] DE102004055716A1 discloses a mixing chamber into which an air supply and a gas supply enter. A line leads out of the mixing chamber and terminates at a burner section. A flame is positioned above the burner section. A temperature sensor can be located, for example, in the area of ​​the flame or on the burner near the flame. A thermocouple can also be used as a temperature sensor. DE102004055716A1 teaches the control of the temperature Tactual generated by a combustion unit to a setpoint temperature Ttarget. A characteristic curve is used that specifies the setpoint temperature Ttarget as a function of the mass flow rate of air and / or the load of the combustion unit. The air-fuel ratio λ remains constant as a further parameter.

[0010] The combustion of pure hydrogen does not generate a practically usable signal at an ionization electrode. Therefore, ionization electrodes are hardly suitable for recording signals during the combustion of pure hydrogen. Consequently, an electronic system controlled by a flame signal is currently only technically feasible for hydrocarbon-containing fuel gases.

[0011] Furthermore, in the case of an electronic system, the combustion output and air supply depend solely on the blower speed. Regarding combustion output, the air-fuel ratio must be adjusted. λ These parameters must be kept constant. If the use of other sensors is too complex, correcting for environmental influences is hardly possible. Such environmental influences include, for example, air temperature, air pressure, and changes in the intake or exhaust air path of the combustion device.

[0012] Another European patent, EP3301362B1, for a method of controlling turbulent flows, was granted on March 25, 2020. The filing date of EP3301362B1 is September 30, 2016.

[0013] EP3301362B1 addresses the recording of an air supply flow using a mass flow sensor. The mass flow sensor can be located in a side channel of an air supply duct of the combustion appliance. The air supply to the combustion chamber of the combustion appliance is determined by two actuators arranged in series. A first actuator receives a first signal, which is a function of the requested flow rate. A second actuator receives a second signal, which is a function of the output from the mass flow sensor. The combined control system according to EP3301362B1 enables compensation for external influences on the air-fuel ratio and / or the combustion output.

[0014] Yet another European patent, EP2995861B1, also deals with mass flow sensors in the areas of valve actuation and diagnostics. Patent EP2995861B1 was granted on August 7, 2019. The filing date for EP2995861B1 is September 10, 2014.

[0015] According to EP2995861B1, a mass flow sensor, which detects a flow rate between 0.1 meters per second and 5 meters per second, is used to detect a leak. First, one of at least two valves connected in series is closed. Then, another valve opens. This opening allows fluid flow.

[0016] A sensor for detecting an airflow is revealed in an article: A 2D thermal flow sensor with sub-mW power consumption. That article was published in 2010 in the journal Sensors and Actuators A: Physical, A163. The article was published on pages 449 to 456 of that journal.

[0017] The article discloses a two-dimensional thermal mass flow sensor with heating elements and thermistors. The disclosed mass flow sensor comprises at least three temperature sensors in the form of three thermistors. A first and a second temperature sensor, each in the form of a first and second thermistor, are arranged on opposite sides of the heating element. A connection between the first and second temperature sensors defines a first direction. A third temperature sensor, also in the form of a third thermistor, is arranged in a second direction. The second direction is perpendicular to the first direction.

[0018] The mass flow sensors from the aforementioned article are claimed in claim 12 of European patent EP3271655B1. EP3271655B1 was filed on March 17, 2016, and granted on November 6, 2019. EP3271655B1 claims priority from March 17, 2015.

[0019] Patent US5401162A, microbridge-based combustion control, was granted on March 28, 1995. US5401162A discloses a combustion device with a first sensor.

[0020] The first sensor is a bridge sensor and is located directly in the flow. A value recorded by the first sensor is compensated for using thermal values.

[0021] Conductivity k and specific heat c p The values ​​of thermal conductivity k and specific heat c p These values ​​are made accessible by an additional sensor. According to column 2, lines 43 to 50, a pulse is introduced by a heating element. The time response to this pulse is then used to determine the thermal conductivity k and the specific heat. c p used.

[0022] In other words, a heating power is used to determine the thermal conductivity k and the specific heat. c p , however, it is not used as a compensable quantity. The heating power from US5401162A serves for compensation, but is not itself compensated.

[0023] Furthermore, equations 1 to 4 in column 3 refer to exactly one reference gas. A derived mapping rule does not depend on the fuel gas composition. In other words, the fuel gas composition in equations 1 to 4 in column 3 is fixed and not variable.

[0024] A European patent application EP1434036A2 was filed on November 13, 2003. The application was published on June 30, 2004. EP1434036A2 relates to a sensor in the form of a thermal flow sensor and a method for correcting its output signal. EP1434036A2 does not relate to a combustion device, but focuses on a sensor. According to claim 1 of EP1434036A2, a flow rate is determined based on corrected temperatures and a stored characteristic curve. The flow rate is not determined based on a heating power as a compensable quantity. According to paragraph

[0022] , the characteristic curve refers to a dust-free sensor.

[0025] The aim is to provide a control system that enables the combustion of fuel gases of varying compositions. These fuel gases may contain hydrogen. In particular, a goal is to provide a control system that achieves a sufficient degree of modulation. Such a system is suitable for fuel gases containing hydrocarbons, mixtures of hydrocarbons containing hydrogen, pure hydrogen, or hydrogen-containing fuel gases with an inert gas component. Hydrogen, in this context, refers to hydrogen gas. Summary

[0026] The scope of protection is defined by the independent and dependent claims.

[0027] Before regulating the air supply and / or the power output of a combustion device, the type of fuel and / or fuel gas must be estimated, determined, and / or calculated. For this purpose, a mass flow sensor is installed in a fuel supply channel of the combustion device. The mass flow channel incorporates a heating element. First, the heating power is determined from a signal from the mass flow sensor.

[0028] Furthermore, several temperatures are determined using the resistance elements of the mass flow sensor. The difference between the determined temperatures is calculated. Both the heating power and the difference are then temperature-compensated.

[0029] The temperature-compensated values ​​can be compared with reference values. Reference values ​​exist, for example, for methane as a fuel gas, for molecular hydrogen as a fuel gas, or for other fuel gas compositions. From this comparison, the type of fuel or fuel gas can be estimated, determined, and / or calculated.

[0030] Temperature compensation of the heating power is preferably performed using a first, empirically determined calibration curve and / or a first, empirically determined calibration function. Temperature compensation of the difference is preferably performed using a second, empirically determined calibration curve. The first, empirically determined calibration curve is advantageously different from the second, empirically determined calibration curve.

[0031] The estimation, determination, and / or calculation of the type of fuel gas and / or fuel is performed by determining distances. Distances are calculated from pairs of values ​​representing temperature-compensated heating output and temperature-compensated difference to the corresponding pairs of values ​​for the reference gases. The fuel and / or fuel gas is then estimated based on the shortest distance to one of the reference gases, such as methane, ethane, or molecular hydrogen.

[0032] The combustion device is controlled based on the estimation, determination, and / or calculation of the type of fuel gas and / or fuel. For example, a minimum air requirement can be assigned to each type of fuel gas and / or fuel. Using this minimum air requirement and the requested power output, the necessary air flow rate can be determined. The target air supply allows the combustion device to be controlled, for example, via at least one air actuator.

[0033] Similarly, a calorific value can be assigned to a type of fuel gas and / or fuel. This calorific value is compared to a set calorific value. For example, the set calorific value could be the one that was configured on the combustion device before the type of fuel gas and / or fuel was estimated, determined, and / or calculated. A correction factor is then determined by relating or normalizing the assigned calorific value to the set calorific value. This allows for adjustments, such as to the air supply to the combustion device, in proportion to the correction factor.

[0034] A further essential objective of the invention is to determine the correct correlation between the measured value and the fuel supply based on the estimated or determined type of fuel gas or fuel. The current fuel supply is determined based on the measured value. The measured value is the heating power of the mass flow sensor and / or one or more of the temperature differences from the measured temperatures of the temperature sensors. The fuel supply can be the fuel mass flow rate, the fuel volume flow rate, or the fuel velocity. One of these values ​​can also be used with reference to specific ambient conditions.

[0035] The combustion device's control system can adjust the fuel supply and / or fuel gas supply based on the current fuel supply value and a corresponding predefined setpoint. The fuel supply and / or fuel gas supply is adjusted using a fuel actuator.

[0036] Furthermore, the current combustion output can be determined based on the estimated or determined type of fuel gas or fuel and its associated calorific value. Here, too, the combustion device's control system can adjust the combustion output using at least one fuel actuator, based on the determined value for the current combustion output and a predefined setpoint. Brief description of the drawings

[0037] Several features will become apparent to a person skilled in the art from the following detailed description of the disclosed non-restrictive embodiments. The drawings accompanying the detailed description can be briefly described as follows: FIG 1 shows a combustion device with a mass flow sensor in the fuel supply channel. FIG 2 shows a sensor element exposed to a flow of water, with various resistance elements. FIG 3 shows the application of the resistive elements of the sensor element to a thin layer and / or film. FIG 4 shows a sensor control unit in communicative connection with the resistance elements. FIG 5 shows a temperature difference across the supply of fuel and / or fuel gas. FIG 6a bis FIG 6c show temperature difference profiles for various fuels and / or fuel gases. FIG 7a bis FIG 7c show curves of heating output as a function of fuel and / or fuel gas supply for various fuels and / or fuel gases. Detailed description

[0038] FIG 1 Figure 1 shows a combustion device 1, such as a wall-mounted gas burner and / or a floor-standing gas burner. During operation, a flame from a heat generator burns in the combustion chamber 2 of the combustion device 1. The heat generator exchanges the thermal energy of the hot combustion gases into another fluid, such as water. The heated water is used, for example, to operate a hot water heating system and / or to heat drinking water. According to another embodiment, the thermal energy of the hot fuels and / or combustion gases can be used to heat a material, for example, in an industrial process. According to a further embodiment, the heat generator is part of a combined heat and power (CHP) plant, for example, an engine of such a plant. According to another embodiment, the heat generator is a gas turbine. Furthermore, the heat generator can be used to heat water in a plant for the production of lithium and / or lithium carbonate.The exhaust gases are discharged from the combustion chamber 2, for example via a chimney 9.

[0039] The combustion air supply 5 is fed to the combustion chamber 2 via the air supply duct 10 by a motor-driven blower 3. The required amount of combustion air is determined by a control unit 13. The control signal 15 transmits this value to the blower 3. It is assumed that the blower 3 will achieve the specified airflow rate. This can be achieved, for example, by internal speed control and / or internal control via an air volume flow or air mass flow sensor (not shown here). The corresponding control unit can also be integrated into the control unit 13.

[0040] The control unit 13 advantageously comprises a microcontroller and / or a microprocessor. In a particular embodiment, the control unit 13 is a microcontroller and / or a microprocessor. The control unit 13 preferably includes a memory such as non-volatile memory.

[0041] Alternatively or additionally, the air supply 5 can be adjusted and / or regulated by an air damper 4. The controlled signal 14 is actually adjusted by the air damper 4. Furthermore, a requested signal 14 can also actually be regulated by the air damper 4. This can be achieved, for example, by position feedback implemented internally in the air damper 4 or via an air volume flow or air mass flow sensor. A control system for two air actuators is described in the aforementioned European patent EP3301362B1. However, the blower 3 can also have a fixed speed, and only the air damper 4 can be adjustable and / or regulated. Furthermore, the air damper 4 can be omitted entirely.

[0042] The fuel 6 is supplied from the fuel source, preferably a gas network or a gas tank, via a mass flow sensor 11 and at least one motor-driven fuel valve 7, 8. Advantageously, the fuel 6 is supplied via one mass flow sensor 11 and two motor-driven fuel valves 7, 8. Subsequently, the fuel 6 is combusted with the supplied air 5.

[0043] The at least one fuel valve 7, 8 is designed as a safety shut-off valve. Consequently, upon a shutdown signal from the control and / or regulating unit 13, the fuel supply 6 can be completely interrupted based on signals 19 and / or 20. Thus, a flame in the combustion chamber 2 is extinguished.

[0044] Preferably, the two fuel valves 7, 8 are designed as safety shut-off valves. The two motor-driven shut-off valves 7, 8 are preferably arranged in series. Consequently, upon a shutdown signal from the control unit 13, the fuel supply 6 can be completely interrupted based on signals 19 and / or 20. Thus, a flame in the combustion chamber 2 is extinguished.

[0045] At least one motor-driven valve 7, 8 is additionally adjustable and / or controllable from a fully closed state, either continuously or with intermediate positions, to a fully open state. The fuel supply 6 can be adjusted by the degree of opening of the fuel valve 7, 8 based on the measured flow rate of the mass flow sensor 11. The adjustment is made to a predetermined setpoint. According to a further embodiment, the fuel supply 6 can be regulated by the degree of opening of the fuel valve 7, 8 based on the measured flow rate of the mass flow sensor 11. The regulation is made to a predetermined setpoint.

[0046] Furthermore, two motor-driven valves 7, 8 can be continuously adjusted and / or regulated from a fully closed state or with intermediate positions to a fully open state. The two motor-driven fuel valves 7, 8 are preferably arranged in series. The fuel supply 6 can be adjusted by the opening degrees of the two fuel valves 7, 8 based on the measured flow rate of the mass flow sensor 11. The adjustment is made to a predetermined setpoint. According to another embodiment, the fuel supply 6 can be regulated by the opening degrees of the fuel valves 7, 8 based on the measured flow rate of the mass flow sensor 11. The regulation is made to a predetermined setpoint.

[0047] The at least one adjustable fuel valve 7, 8 does not necessarily have to be designed as a safety shut-off valve. The fuel supply 6 is then determined and / or regulated via an additional adjustable fuel valve. The position of the additional adjustable fuel valve is controlled by the control loop in the control unit 13 using the signal from the mass flow sensor 11. Thus, the fuel supply 6 is also regulated.

[0048] According to one embodiment, the two adjustable fuel valves 7, 8 do not necessarily have to be designed as safety shut-off valves. Two independent safety shut-off valves 7, 8 can also be used, which can only open and close completely. The fuel supply 6 is then determined and / or regulated via another adjustable fuel valve. The position of the additional, adjustable fuel valve is controlled by the control loop in the control unit 13 using the signal from the mass flow sensor 11. Thus, the fuel supply 6 is also regulated.

[0049] The mass flow sensor 11 preferably comprises a measuring and control unit 12. The measured signals are processed in the measuring and control unit 12. Three signals 16, 17, and 18 are transmitted to the control and / or monitoring unit 13. These signals contain information about the flow rate and the fuel composition and / or fuel gas composition. In a compact embodiment, the mass flow sensor 11 does not include the measuring and control unit 12. Instead, the measuring and control unit 12 can be partially or completely integrated into the control and / or monitoring unit 13.

[0050] The measuring and control unit 12 of the mass flow sensor 11 advantageously comprises a microcontroller and / or a microprocessor. In a particular embodiment, the measuring and control unit 12 of the mass flow sensor 11 is a microcontroller and / or a microprocessor. The measuring and control unit 12 of the mass flow sensor 11 preferably includes a memory such as non-volatile memory.

[0051] The mass flow sensor 11 preferably comprises the measuring and control unit 12 and a sensor element 21. The structure of the sensor element 21 is described in FIG 2 and in FIG 3 The sensor element 21 comprises a sensor substrate.

[0052] A thin layer and / or film 22 is applied to the sensor substrate. The sensor substrate, or a portion thereof, is removed beneath surfaces 23 and 24. Consequently, the temperature-dependent resistive elements 26, 27, 28, and 29 are located almost exclusively on the thin layer and / or film 22. This results in thermal decoupling of the resistive elements 26, 27, 28, and 29 from the sensor substrate. Preferably, good thermal decoupling of the resistive elements 26, 27, 28, and 29 from the sensor substrate is achieved. Ideally, very good thermal decoupling of the resistive elements 26, 27, 28, and 29 from the sensor substrate is achieved.

[0053] Temperature changes in the resistance elements 26, 27, 28, and 29 occur rapidly due to their low heat capacities and low heat dissipation. Preferably, these temperature changes occur very rapidly. A flowing medium, such as a fuel gas 6, flows over surfaces 23 and 24 and thus over the resistance elements 26, 27, 28, and 29. The resistance elements 26, 27, 28, and 29 are arranged as shown in FIG 4 shown controlled by the measuring and control unit 12.

[0054] In a particular embodiment, the measuring and control unit 12 for controlling the resistive elements 26, 27, 28, and 29 comprises one or more digital-to-analog converters. The one or more digital-to-analog converters convert digital control signals to the resistive elements 26, 27, 28, and 29 into analog signals. The one or more digital-to-analog converters can, for example, be used to send an electric current through one of the resistive elements 26, 27, 28, and 29. The electric current is preferably a predetermined electric current. In a compact embodiment, the one or more digital-to-analog converters can be fully integrated into the measuring and control unit 12. In particular, the one or more digital-to-analog converters and the measuring and control unit 12 can form a single-chip system.Thus, one or more digital-to-analog converters and a microcontroller of the measurement and control unit 12 can form a single-chip system. Furthermore, one or more digital-to-analog converters and a microprocessor of the measurement and control unit 12 can form a single-chip system.

[0055] In another specific embodiment, the measuring and control unit 12 for reading the signals from the resistive elements 26, 27, 28, and 29 comprises one or more analog-to-digital converters. The one or more analog-to-digital converters convert analog signals at the resistive elements 26, 27, 28, and 29 into digital signals. The one or more analog-to-digital converters can be used, for example, to read an electrical voltage across one of the resistive elements 26, 27, 28, and 29. In a compact embodiment, the one or more analog-to-digital converters can be fully integrated into the measuring and control unit 12. In particular, the one or more analog-to-digital converters and the measuring and control unit 12 can form a single-chip system. For example, the one or more analog-to-digital converters and a microcontroller of the measuring and control unit 12 can form a single-chip system.Furthermore, one or more analog / digital converters and a microprocessor of the measurement and control unit 12 can form a single-chip system.

[0056] The measuring and control unit 12 of the mass flow sensor 11 comprises a sensor control unit 32, such as a central sensor control unit 32. The sensor control unit 32 supplies a constant electrical current to the resistor elements 27, 28, and 29 located on the sensor element 21. Furthermore, the sensor control unit 32 supplies a constant electrical current to a reference resistor 30 located within the measuring and control unit 12.

[0057] The constant electric current is chosen to be so small that the resistive elements 27, 28, and 29 are practically not heated by this current. Using the known value of the reference resistor 30, the electric current through the resistive elements 27, 28, and 29 can be precisely determined based on a measured electric voltage 37. The temperature-dependent values ​​of the resistive elements 27, 28, and 29 can be calculated from the electric voltages 34, 35, and 36 and the determined electric current. This calculation is preferably performed by the sensor control unit 32.

[0058] The sensor control unit 32 advantageously comprises a microcontroller and / or a microprocessor. In a particular embodiment, the sensor control unit 32 is a microcontroller and / or a microprocessor. The sensor control unit 32 preferably comprises a memory such as non-volatile memory. In a central embodiment, the central sensor control unit 32 advantageously comprises a microcontroller and / or a microprocessor. In a particular embodiment, the central sensor control unit 32 is a microcontroller and / or a microprocessor. The central sensor control unit 32 preferably comprises a memory such as non-volatile memory.

[0059] Furthermore, at least one analog / digital converter for reading the signals of the resistor elements 26, 27, 28 and 29 is preferably integrated in the sensor control unit 32.

[0060] In a further preferred embodiment, at least one analog-to-digital converter for reading the signals from the resistor elements 26, 27, 28, and 29 is implemented separately from the sensor control unit 32. In a particularly preferred embodiment, the signal from the at least one analog-to-digital converter to the sensor control unit 32 is then transmitted via a bus. A suitable bus could be, for example, an SPI bus or a CAN bus.

[0061] Using a known resistance-temperature characteristic curve, the temperature of each resistance element 27, 28, and 29 can be determined based on its respective resistance value. The resistance-temperature characteristic curve for each of the three resistance elements 27, 28, and 29 is preferably determined by means of temperature calibration. The resistance-temperature characteristic curve for each of the three resistance elements 27, 28, and 29 is preferably stored in the sensor control unit 32. For example, the resistance-temperature characteristic curve for each of the three resistance elements 27, 28, and 29 can be stored in a non-volatile memory of the sensor control unit 32.

[0062] The resistance element 29 is thermally decoupled from the other resistance elements 26, 27 and 28, as it is located in its own thermal island.

[0063] The resistance element 29 can thus detect and / or record a signal that indicates practically exclusively the temperature of the flowing fuel 6. Preferably, the resistance element 29 can thus detect and / or record a signal that indicates practically exclusively the temperature of the flowing fuel gas 6. Preferably, the resistance element 29 can detect and / or record a signal that indicates a very precise temperature of the flowing fuel 6. Ideally, the resistance element 29 can detect and / or record a signal that indicates a very precise temperature of the flowing fuel gas 6.

[0064] The resistive element 26 serves as a heater and temperature sensor. A signal indicating the temperature TH of the resistive element 26, configured as a heating element, can be recorded from the resistive element 26. For heating, the voltage across the heating element 26 and the series resistor 31 is applied by the sensor control unit 32 to a driver 33. The driver 33 provides sufficient current and power to heat the resistive element 26.

[0065] Using the electrical voltage 39 across the series resistor 31, the current through the heating resistor 26 can be determined by the sensor control unit 32. With the calculated current and the electrical voltage 38, the temperature-dependent value of the heating resistor 26 can be calculated. Preferably, the temperature-dependent value of the heating resistor 26 is calculated by the sensor control unit 32.

[0066] The temperature TH of the heating resistor 26 can be precisely determined using a resistance-temperature characteristic curve and the temperature-dependent value of the heating resistor 26. The resistance-temperature characteristic curve for the heating resistor 26 is preferably determined by means of temperature calibration. The resistance-temperature characteristic curve for the heating resistor 26 is preferably stored in the sensor control unit 32. For example, the resistance-temperature characteristic curve for the heating resistor 26 can be stored in a non-volatile memory of the sensor control unit 32.

[0067] The temperature TH of the heating resistor 26 can be set or regulated by adjusting the voltage at the output of driver 33. The temperature TH of the heating resistor 26 can be measured and / or determined via voltages 38 and 39.

[0068] The heating element 26 is operated in the so-called CTA mode (Constant Temperature Anemometer mode). This means that the temperature of the heating element 26 is determined by means of a

[0069] Temperature control is regulated to a constant excess temperature of ΔTH. The excess temperature ΔTH is defined as the difference between the temperature TH of the heating element 26 and the temperature of the fuel 6 TM: ΔTH = TH − TM

[0070] A signal indicating the temperature TM of the fuel 6 is recorded using the resistance element 29. The temperature difference ΔTH is advantageously defined as the difference between the temperature TH of the heating element 26 and the temperature TM of the fuel gas 6. ΔTH = TH − TM

[0071] A signal indicating the temperature TM of the fuel gas 6 is recorded using the resistance element 29. Temperature control to a constant overtemperature is preferably carried out by the sensor control unit 32. Ideally, the temperature control to a constant overtemperature is performed by a controller within the sensor control unit 32. The overtemperature ΔTH typically has values ​​of 20 Kelvin, 40 Kelvin, 60 Kelvin, or even 80 Kelvin.

[0072] When fuel flows over heating element 26, the heating element 26 is cooled to varying degrees depending on the flow velocity 25 and the composition of the fuel 6. Preferably, the fuel 6 is a fuel gas. In this case, the heating element 26 is cooled to varying degrees depending on the flow velocity 25 and the composition of the fuel 6. If the flow velocity 25 increases with the same fuel and / or fuel gas composition, the heating element 26 is also cooled more.

[0073] To ensure that the excess temperature ΔTH remains constant, the temperature controller must increase the heating power PH accordingly when the flow rate increases. The heating power PH is specified in the Figuren 7a, 7b und 7c Signal 48 is plotted along the vertical axis. Signal 16 is a measure of the supply of fuel 6 and / or the supply of fuel gas 6. In particular, signal 16 is a measure of the mass flow rate of fuel 6 and / or fuel gas 6.

[0074] The heating power PH is thus a measure of the flow velocity across the mass flow sensor 11. The heating power PH can be calculated from the measured voltages 38 and 39 using the known series resistance 21. PH is preferably calculated in the sensor control unit 32.

[0075] The resistance elements 27 and 28 are located laterally to the heating element 26. If the heating element 26 is heated by a value ΔTH above the fuel gas temperature TM, the two resistance elements 27 and 28 are also heated. The resistance elements 27 and 28 are heated because they are thermally coupled to the heating element 26 via the thin layer and / or film 22 and the flowing fuel 6. Preferably, the thermal coupling occurs via the thin layer and / or film 22 and the flowing fuel 6 and / or the flowing fuel gas 6.

[0076] Using the respective resistance temperature characteristics of the resistance elements 27 and 28, the respective resistance temperatures can be determined based on the measured resistance values ​​of 27 and 28. The resistance temperature characteristics of the resistance elements 27 and 28 are preferably stored in the sensor control unit 32. Ideally, the resistance temperature characteristics of the resistance elements 27 and 28 are stored in a non-volatile memory of the sensor control unit 32.

[0077] Resistance element 27 is located upstream of heating resistor 26. Therefore, an upward resistance temperature TU is determined based on resistance element 27. Resistance element 28 is located downstream of heating resistor 26. Therefore, a downward resistance temperature TD is determined based on resistance element 28.

[0078] Both temperatures TU and TD are caused by the temperature difference ΔTH relative to the temperature TM of the fuel 6 and / or fuel gas 6. Consequently, two further differences can be determined. ΔTU = TU − TM and ΔTD = TD − TM Calculate. Preferably, the calculations of the differences ΔTU and ΔTD are performed by the sensor control unit 32. The difference ΔTU corresponds to signal 16. The difference ΔTD corresponds to signal 17. The heating power PH corresponds to signal 18. Advantageously, the difference ΔTD and the heating power PH are temperature-compensated by the control unit 13.

[0079] If the flow velocity is increased while maintaining the same fuel gas composition, ΔTU (signal 16) decreases. This is because the resistance element 27, which determines ΔTU (signal 16), receives its heat exclusively via thermal conduction through the thin layer or film 22. As soon as the medium flows over the sensor element 21, the heat is dissipated from the resistance element 27. Consequently, there is little to no heat transfer from the heating element 26 to the resistance element 27 via the fuel 6 and / or the fuel gas 6.

[0080] As the flow velocity 25 increases, the heat supplied to the resistance element 27 via the thin layer and / or film 22 is increasingly carried away by the flowing fuel 6 and / or combustion gas 6. Consequently, the resistance element 27 is increasingly cooled. The difference ΔTU (signal 16) therefore decreases with increasing flow velocity 25.

[0081] If the flow velocity 25 is kept constant and the composition of the fuel 6 and / or fuel gas 6 is changed, the heating element 26 is initially cooled to a greater or lesser extent. However, the temperature of the heating element 26 is kept constant by the temperature control. Preferably, the temperature control is carried out by the sensor control unit 32.

[0082] Likewise, the resistance element 27 is cooled by the same amount. Due to the strong thermal coupling of the resistance element 27 to the heating resistor 26 via the thin layer and / or foil 22, this loss is compensated for by the temperature control. Consequently, the difference ΔTU (signal 16) does not change practically when the fuel 6 and / or fuel gas 6 is varied.

[0083] The medium is a fuel 6 and / or a fuel gas 6. The medium temperature TM is a temperature of the fuel 6 and / or the fuel gas 6. A change in the medium temperature TM has no direct effect due to the difference between the measured value and the actual medium temperature TM.

[0084] However, the change in the medium temperature TM also has an effect on selected material constants such as kinematic viscosity and / or the thermal conductivity of the fuel 6 and / or fuel gas 6. Therefore, the change in the medium temperature TM has an effect similar to that of a change in the composition of the fuel 6 and / or fuel gas 6.

[0085] Similar to a change in fuel composition and / or fuel gas composition, a temperature change of the fuel 6 and / or fuel gas 6 does not affect the difference ΔTU (signal 41). The difference ΔTU (signal 16) is therefore largely independent of the temperature of the supplied fuel 6 and / or fuel gas 6. Over a wide range of fuel compositions and / or fuel gas compositions, the difference ΔTU (signal 16) depends only on the flow velocity or fuel supply 25 across the sensor element 21.

[0086] The mass flow sensor 11 with the sensor element 21 can be installed in a fixed geometry with a constant cross-sectional area. Then ΔTU (signal 16) is largely independent of fuel composition and / or fuel gas composition, as well as largely independent of fuel temperature and / or fuel gas temperature, and depends only on the mass flow rate of the fuel 6 or fuel gas 6.

[0087] From ΔTU (signal 16), the corresponding flow velocity and / or fuel supply and / or fuel gas supply is determined via characteristic curve 41. The shape of a typical characteristic curve 41 is shown in FIG 5 The value 40 represents the flow velocity and / or fuel supply 25 for all temperatures and / or fuel compositions, calculated using the characteristic curve 41. Preferably, the sensor control unit 32 determines the signal 16. Preferably, the sensor control unit 32 transmits the signal 16 to the control unit 13. Preferably, the flow signal 40 is calculated in the control unit 13 using the characteristic curve 41. The flow signal 40 corresponds to the flow velocity 25 and / or fuel supply 6.

[0088] The characteristic curve 41 of signal 16 via signal 40 is determined once by means of a flow calibration. Preferably, the characteristic curve of signal 16 via signal 40 is stored in the control unit 13. Ideally, the characteristic curve of signal 16 via signal 40 is stored in a non-volatile memory of the control unit 13.

[0089] FIG 6 Figure 17 shows three different diagrams for ΔTD (signal 17) at different temperatures for different fuels 6 and / or fuel gases 6, plotted against signal 42. Signal 42 represents the flow velocity 25 and / or the fuel supply 6, measured from the ΔTD value (signal 17). The dependence on the fuel gas composition arises because the heat from the heating element 26 does not only reach the resistance element 28 via the thin layer and / or film 22. Instead, heat also reaches the resistance element 28 from the heating element 26 via the fuel 6 and / or the fuel gas 6. Therefore, the temperature of the resistance element 28 also depends on the material properties of the fuel 6 and / or fuel gas 6.

[0090] Characteristic curve 44 shows the behavior for methane as fuel gas 6. This fuel gas 6 was selected here as an example reference. Characteristic curve 45 shows the behavior for the reference gas methane with admixtures of higher-energy fuel gases 6, such as ethane or propane. Characteristic curve 46 shows the behavior for a fuel gas with admixtures of, for example, nitrogen as an inert gas. Characteristic curve 47 shows a mixture of methane as fuel gas 6 with hydrogen, while characteristic curve 48 shows a characteristic curve for pure hydrogen and / or for pure hydrogen gas.

[0091] Because the material properties of fuels 6 and / or fuel gases 6 are temperature-dependent, an overall temperature dependence results for all fuel mixtures and / or fuel gas mixtures. FIG 6b The characteristic curves of the described fuels 6 and / or fuel gases 6 are shown for a reference temperature such as 293 Kelvin.

[0092] FIG 6a shows the corresponding characteristic curves for a lower temperature, FIG 6c The graph shows the characteristic curves at a higher temperature. Temperature compensation converts the characteristic curves from a lower or higher temperature to the corresponding characteristic curves at the reference temperature.

[0093] In the simplest case, this is achieved by shifting the characteristic curves according to a fixed formula previously determined by laboratory measurements on the reference gas. This fixed formula can, for example, be stored in the control unit 13. Advantageously, the fixed formula is stored in a non-volatile memory of the control unit 13.

[0094] More complex calculation rules are also conceivable, for example, the interpolation between two stored characteristic curves at different temperatures for a reference gas. Temperature compensation is performed by applying the compensation rule of the characteristic curves to a temperature difference ΔTD (signal 17). In all conversions, the ratios 44 to 48 between fuels 6 and / or fuel gases 6 are maintained.

[0095] In another preferred method, the conversion to the characteristic curves of the reference temperature is carried out by a rotational stretching. The parameters of the rotational stretching are determined by measurements with reference gases. They are preferably stored in the non-volatile memory of the control unit 13. For example, the relationships can be determined empirically in the laboratory using test specimens and are then valid for all sensor specimens.

[0096] In a further step, for various fuel gases, for example fuel gases 44 to 48, the respective temperature-compensated value is mapped to the value for the reference gas. In the simplest case, this is done by shifting the characteristic curves according to a fixed formula previously determined by laboratory measurements on the reference gas. Alternatively, interpolation can be performed between any two characteristic curves. A rotational stretching operation is particularly preferred, in which the characteristic curves for each selected fuel gas are mapped to the characteristic curve of the reference gas. Here, too, the formulas for the individual fuel gases are stored, for example, in the control unit 13. The fixed formulas are advantageously stored in a non-volatile memory of the control unit 13. They can also be empirically determined in the laboratory and are then valid for all sensor units.

[0097] The last two steps can be combined and performed in a single diagram. In the case of rotational stretching, a rotational stretch is then obtained for each fuel gas 44 to 48, which is a function of the fuel temperature. Here, too, the specifications are preferably stored in the control unit 13. The fixed specifications are advantageously stored in a non-volatile memory of the control unit 13. All relationships or diagrams can also be determined by empirical measurements in the laboratory and are then valid for all sensor units.

[0098] The compensation, in the form of a rotational stretch, also incorporates a calibration characteristic curve. The result of the compensation, including a calibration characteristic curve, is the flow value 25 for the fuel supply 6 and / or for the fuel gas supply 6. In particular, the result of the compensation, including a calibration characteristic curve, can be the flow value 25 for the fuel supply 6 and / or the fuel gas supply 6.

[0099] The calibration curve shows the relationship between the determined value ΔTD and the flow rate 25 of the fuel supply 6 for the reference gas at the reference temperature. The calibration curve does not include fuel-specific properties or temperature dependence, but only the specific properties of a particular sensor sample.

[0100] This approach is advantageous because the temperature dependence of the fuel gas and the dependence of the fuel gas composition can be empirically determined as material parameters in the laboratory. The empirical determination in the laboratory is performed independently of the specific sensor sample on multiple sensors. Figure 41 can be stored as a fixed function of any fuel gas composition and as a function of the medium temperature TM. The calibration characteristic curve with the geometric properties therefore only needs to be determined for one fuel, namely a reference fuel. The calibration characteristic curve with the geometric properties therefore only needs to be determined for one gas, namely the reference gas.

[0101] Signal 42 is obtained from signal 17 as a result and / or starting point. Signal 42 is temperature-compensated. Signal 42 is preferably independent of the fuel composition and / or the fuel gas composition. Signal 42 represents the flow velocity 25, converted to the reference fuel, calculated from signal ΔTD (signal 17). For each fuel characteristic curve 44 to 48, a rotational stretch as a function of the fuel temperature is preferably stored in the control unit 13. In addition to the rotational stretch, the calibration characteristic curve for TD is stored, preferably in the control unit 13. The characteristic curve or parameters for the rotational stretch or the mapping for temperature and fuel gas compensation are preferably stored in a non-volatile memory of the control unit 13.The calibration characteristic for each sensor is advantageously stored in a non-volatile memory of the control unit 13. Signal 17 is preferably transmitted from the sensor control unit 32 to the control unit 13.

[0102] As an alternative to the difference ΔTD (signal 17), derived values ​​such as ΔTDU = TD − TU can be used. You then get similar values ​​to those in Fig 6a,6b und 6c The mapping of signal 17 to the reference signal 42 is performed in the same manner. The mapping is carried out using, for example, empirically determined functions 44 to 48 for each fuel gas and the measured fuel gas temperature. Here, too, the empirically determined functions 44 to 48 are preferably stored in the non-volatile memory of the control unit 13. Furthermore, the calibration characteristic curve from the reference gas to the flow value 25 of the fuel supply 6 is preferably stored in the non-volatile memory of the control unit 13.

[0103] The power value PH (signal 18) resulting from the heating control is processed in the same way as signal 17 (signal ΔTD or signal ΔTDU). FIG 7 The curves of performance values ​​PH (signal 18) versus the supply of fuel 6 and / or fuel gas 6 for three different fuel gas temperatures are shown. The characteristic curves apply to the same fuel compositions and / or fuel gas compositions as in FIG 6 described. FIG 7b This shows the characteristic curves for a mean temperature that has been selected as a reference temperature. The selected reference temperature can be, for example, 293 Kelvin. FIG 7a shows the characteristic curves at a lower fuel temperature and / or combustion gas temperature. FIG 7c shows the characteristic curves for a higher fuel temperature and / or combustion gas temperature.

[0104] Temperature compensation to the reference temperature is most easily achieved here by a factorial correction. A correction factor for various temperatures in the laboratory is recorded. The correction factor can be stored, for example, in the sensor control unit 32 or, preferably, in the control unit 13. Advantageously, the correction factor is stored in non-volatile memory in the sensor control unit 32 or the control unit 13.

[0105] More complex temperature compensation rules are also possible, for example, by linear interpolation between two characteristic curves for different temperatures of the reference gas. These two characteristic curves can be stored, for instance, in the control unit 13. Advantageously, the two characteristic curves are stored in a non-volatile memory of the control unit 13. Other more complex rules are also possible, such as rules taking signal 16 into account. Alternatively, rotational stretching can be used for temperature compensation. Rotational stretching also involves a conversion based on a calibration characteristic curve. The parameters for rotational stretching can be determined by measurements with reference gases 49 to 53 from signal 18 to signal 43. They are preferably stored in the non-volatile memory of the control unit 13.Temperature compensation is achieved by applying the compensation formula of the characteristic curves to the measured power value PH (signal 18). Here too, relationships 49 to 53 can be empirically determined in the laboratory using test samples and are valid for all sensor samples.

[0106] Characteristic curve 49 shows the behavior for methane as fuel gas 6. This fuel gas 6 was selected here as an example reference. Characteristic curve 50 shows the behavior for the reference gas methane with admixtures of higher-energy fuel gases 6, such as ethane or propane. Characteristic curve 51 shows the behavior for a fuel gas with admixtures of, for example, nitrogen as an inert gas. Characteristic curve 52 shows a mixture of methane as fuel gas 6 with hydrogen, while characteristic curve 53 shows a characteristic curve for pure hydrogen.

[0107] In a further step, for various fuel gases, for example fuel gases 49 to 53, a mapping of the respective temperature-compensated value to the value for the reference gas is carried out. Here, too, in the simplest case, this is done by shifting the characteristic curves according to a fixed formula that was previously determined by laboratory measurements on the reference gases.

[0108] Alternatively, interpolation can be performed between any two characteristic curves. A rotational stretching can be particularly preferred, in which the characteristic curves for each selected fuel gas are mapped onto the characteristic curve of the reference gas. This compensation using rotational stretching is consistent with the existing thermodynamic model of the sensor. Here, too, the specifications for the individual fuels and / or fuel gases are stored, for example, in the control unit 13. The fixed specifications are advantageously stored in a non-volatile memory of the control unit 13. They can, for example, be determined empirically in the laboratory and are then valid for all sensor units.

[0109] As with the signals ΔTU and ΔTDU, the last two steps for the power value PH can be combined into a single mapping. In the case of rotational stretching, this results in a rotational stretch as a function of the fuel temperature for each fuel gas 49 to 53. The mapping rules 49 to 53 for the power value are preferably stored in the control unit 13. The fixed mapping rules are advantageously stored in a non-volatile memory of the control unit 13. All relationships or mappings 49 to 53 can also be determined by empirical measurements in the laboratory. They are then valid for all sensor units.

[0110] To accurately estimate the correct fuel and / or fuel gas, characteristic curves 49 to 53 must correspond to fuel gases 44 to 48. This means that the fuel gas for characteristic curve 44 is the same as for characteristic curve 49 (methane is used as an example here). The fuel gas for characteristic curve 45 is the same as for characteristic curve 50 (methane with propane is used as an example here). The fuel gas for characteristic curve 46 is the same as for characteristic curve 51 (methane with nitrogen is used as an example here). The fuel gas for characteristic curve 47 is the same as for characteristic curve 52 (methane with hydrogen is used as an example here). The fuel gas for characteristic curve 48 is the same as for characteristic curve 53 (pure hydrogen is used as an example here). The characteristic curves 43 to 48 and 49 to 53 shown here can, of course, be extended to include other fuel gas compositions with different characteristic curves.

[0111] As part of the compensation process, a calibration characteristic curve for the power PH and / or the power value PH for the reference gas is stored, preferably in the control unit 13. In particular, as part of the rotational stretching process, a calibration characteristic curve for the power PH and / or the power value PH for the reference gas is stored, preferably in the control unit 13. The characteristic curve or the parameters for the rotational stretching or mapping for temperature and fuel gas compensation are preferably also stored for PH in the control unit 13. This storage is, for example, in a non-volatile memory of the control unit 13. The calibration characteristic curve for each sensor is also advantageously stored in a non-volatile memory of the control unit 13.

[0112] One obtains a value from the measured signals 16 (for ΔTU), 17 (for ΔTD or ΔTDU) and 18 (for PH) as well as the medium temperature TM for every fuel gas.

[0113] This value corresponds to the respective measured value for ΔTU, ΔTD / ΔTDU, and PH for the reference gas. The flow velocity / fuel gas supply 40, 42, and 43 can now be determined for each fuel gas. This determination is based on a calibration curve of the reference gas for ΔTU, ΔTD / ΔTDU, and PH. The calibration curve(s) are determined individually for each sensor. If the respective fuel gas actually flows through sensor 21, then all three values ​​40, 42, and 43 correspond to the flow velocity 25. These values ​​40, 42, and 43 also correspond to the fuel supply 6 and / or the fuel gas supply 6.

[0114] If the fuel gas is known, one of the signals 16, 17, or 18 can be selected. Based on the medium temperature, the calibration curve, and the known mapping rule 41 or 43 to 48 or 49 to 53, the value 40 or 42 or 43 is determined. This determination assumes a known fuel gas and / or fuel. The value 40 or 42 or 43 is a measure of the flow velocity 25. The fuel supply can also be determined in this way.

[0115] Signals 16, 17, and 18 differ in quality because they were acquired using different sensors. Signal 16 (ΔTU) is largely independent of temperature and, to a wide extent, also independent of the fuel gas composition. Therefore, the flow velocity 25 or the fuel supply can be determined using a characteristic curve 41 for almost all fuel gases and all fuel gas temperatures. If a deviation exists for one or more special gases, different characteristic curves can be stored and selected in the control unit 13. This is illustrated above for ΔTD.

[0116] Signal 17 (ΔTD or ΔTDU) is very accurate for small flow rates from 0.1 m / s to 20 m / s. Signal 18 (PH), on the other hand, has a large measuring range, allowing flow rates from 0.5 m / s to 100 m / s to be measured with sufficient accuracy. Depending on the measured flow rate, signals 41, 42, or 43 can be selected. For small values, such as less than 5 m / s, signal 42 can be chosen. For larger values, such as greater than 5 m / s, signal 43 can be selected. It is common practice to incorporate hysteresis at the switching point. Therefore, when approaching from below, the switchover from signal 42 to signal 43 occurs, for example, at 5.5 m / s. When approaching from above, the switchover from signal 43 to signal 42 occurs, for example, at 4.5 m / s.

[0117] It remains particularly advantageous to include air as an additional gas and select it as a reference gas. This allows the calibration characteristic curve to be determined very easily using air, and the flow velocity of the fuel gas or fuel supply for each fuel gas to be determined according to the respective calibration formula.

[0118] If a sensor is to be calibrated for a specific fuel gas, a mapping rule can be selected by choosing the fuel gas via the control program. The mapping rule is preferably stored in the non-volatile memory of the control unit 13. The flow value 40, 42, or 43 is determined from the measured value 16, 17, or 18 and the calibration curve for the reference gas. This value 40, 43, or 43 then corresponds to the correct flow velocity 25 or the correct fuel supply.

[0119] Furthermore, the gas composition for an unknown fuel gas can also be estimated. To do this, starting from signals 16 and / or 17 and / or 18, the flow value 40 is determined for each possible fuel gas composition using the mapping rule 41 and the reference characteristic curve. The reference characteristic curve is a characteristic curve of the calibration gas for ΔTU. Furthermore, all flow values ​​42 for each fuel gas are determined using all assignments 44 to 48 and the reference characteristic curve of the calibration gas for ΔTD / ΔTDU. In addition, the flow value 43 for each fuel gas is determined using all assignments 49 to 53 and the reference characteristic curve of the calibration gas for PH.

[0120] For each fuel gas, the difference between the determined flow values ​​(signal 40 - signal 42), (signal 40 - signal 43), and (signal 42 - signal 43) is calculated. The result is then squared. A sum of squares σ is calculated for each fuel and / or fuel gas. The sum of squares σ can be used as a measure to determine the gas composition by selecting the composition with the smallest value σ. The sum of squares can be calculated not only by simple addition, but each individual square can be weighted by a factor before addition. This allows for the consideration of different influences of the fuel gas compositions on signals 40, 42, and 43.

[0121] The selected gas composition can then be used to perform a procedure by choosing one of the three selected values ​​40, 42, or 43 for the known gas composition. Here too, different result values ​​40, 42, or 43 can be selected depending on the determined value, and hysteresis is also possible when switching between the values.

[0122] One can also calculate the square of just one difference for the values ​​of all gas compositions. This single difference is selected from one of the following: Signal 40 - Signal 42, Signal 40 - Signal 43, Signal 42 - Signal 43.

[0123] The measure σ for each gas composition then corresponds to the squared difference value of each gas composition.

[0124] Here too, the gas composition with the minimum value of σ is selected. Depending on the type of gas composition, an estimate based on just one squared difference may suffice. However, in general, better discrimination is achieved by using the difference of the sum of two or even three squared differences.

[0125] The measuring and control unit 12 transmits the signals 16 and / or 17 and / or 18 to the control and / or monitoring unit 13. The measuring and control unit 12 is advantageously part of the mass flow sensor 11. In a further, more compact embodiment, the measuring and control unit 12 can be integrated into the control and / or monitoring unit 13.

[0126] The fineness of the gas composition can be selected by the quantity of gas compositions and thus the quantity of imaging rules 41, 44 to 48, and 49 to 53, respectively. To suppress the influence of noise, signals 16 and / or 17 and / or 18 can be averaged over a shorter or longer period. A short period of 0.2 seconds can be considered suitable. A longer and recommended period of 5 seconds can be considered suitable. A very long period of 30 seconds or even 60 seconds can be considered suitable.

[0127] With the selected gas composition, the gas mixture and thus the material parameters of the selected fuel gas are known. Therefore, the calorific value (Hu) and / or the minimum air requirement (Lmin) of the selected fuel gas are also known. The material parameters, for example, Hu and / or Lmin, are preferably stored in the control unit 13, as shown in Figures 41, 44 to 48, and 49 to 53. They are assigned to a fuel gas. Once the fuel gas has been selected, the stored material parameters, for example, Hu and / or Lmin, can be selected, just as the assignment can be. The material parameters, for example, Hu and / or Lmin, are preferably stored in the non-volatile memory of the control unit 13.

[0128] The currently determined correction factor of Hu, relative to the correction factor under set conditions, is used to correct the supply of fuel 6 and / or fuel gas 6. Preferably, this correction is performed by the control unit 13. For this purpose, the selected signal 40, 42, and / or 43 can be multiplied by the reciprocal of the currently determined correction factor. The selected signal is a measure of the flow velocity 25 and / or the amount of fuel 6 and / or fuel gas 6 supplied. Similarly, the setpoint for the supply of fuel 6 and / or fuel gas 6 can be multiplied by the currently determined correction factor. In general, the supply of fuel 6 and / or fuel gas 6 is changed in proportion to the correction factor.

[0129] This allows a fuel control loop in the control and / or regulating unit 13 to correct at least one fuel valve 7, 8. As a result of the correction, a correct supply of fuel 6 and / or fuel gas 6 is set and / or regulated. This also corrects the power output of the combustion device 1.

[0130] The air supply can be corrected using the known, corrected supply of fuel 6 and / or fuel gas 6 and its associated signal 16. A compound curve is used for the correction. The compound curve can, for example, be stored in the control unit 13. Advantageously, the compound curve is stored in a non-volatile memory of the control unit 13.

[0131] The control unit 13 changes the setpoint for the air supply 5 assigned in the compound curve with the currently determined correction factor of Lmin in relation to the correction factor under setting conditions. An air control loop corrects the air supply 5 via the motor-driven blower 3 and / or via the motor-driven air damper 4.

[0132] Alternatively, the measured value for the air supply 5 can be corrected first. Then, the supply of fuel 6 and / or fuel gas 6 assigned via the system is corrected, which leads to the same result.

[0133] Within the context of this disclosure, compensation of a first value as a function of a second value means that the influence of the second value on the first value is reduced and / or suppressed. In other words, the first value is compensated by the second value. That is to say, the first value is compensated in dependence on the second value. The same applies in the case of dependencies on third and further values.

[0134] Within the context of this disclosure, the compensability of a first value as a function of a second value means that the influence of the second value on the first value is reduced and / or suppressed. In other words, the first value is compensable by the second value. This means that the first value is compensable depending on the second value. The same applies in the case of dependencies on third and further values.

[0135] In other words, the present disclosure relates to a method for estimating a flow rate (25) for fuels (6) and / or fuel gases (6) of different compositions supplied to a combustion device (1) via a fuel supply channel and / or fuel gas supply channel, wherein the combustion device (1) comprises a mass flow sensor (11), wherein the mass flow sensor (11) is in fluid communication with the fuel (6) and / or with the fuel gas (6), the method comprising the steps: Recording a first temperature signal, indicating a first temperature of the fuel (6) and / or the fuel gas (6), using a first resistance element (29) of the mass flow sensor (11); processing the first temperature signal to obtain a first temperature (TM); determining a compensable value by recording a heating power signal, indicating a heating power of a heating element (26) of the mass flow sensor (11); processing the heating power signal to obtain a heating power; determining the compensable value as heating power;and estimating a flow value (25) for the fuel supply and / or for the fuel gas supply by compensating the value that can be compensated as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition using at least one stored mapping rule that depends on the first temperature (TM) and / or on the fuel composition and / or on the fuel gas composition, and using a calibration characteristic curve stored for a reference gas.

[0136] The present disclosure further relates to a method for estimating a type of fuel (6) and / or a type of fuel gas (6) in a combustion device (1) with a mass flow sensor (11), wherein the mass flow sensor (11) is in fluid communication with the fuel (6) and / or with the fuel gas (6), the method comprising the steps: Recording a heating power signal indicating the heating power of a heating element (26) of the mass flow sensor (11); recording a first temperature signal indicating a first temperature of the fuel (6) and / or the fuel gas (6) based on a first resistance element (29) of the mass flow sensor (11); recording a second temperature signal indicating a second temperature of the fuel (6) and / or the fuel gas (6) based on a second resistance element (27, 28) of the mass flow sensor (11), wherein the second resistance element (27, 28) is different from the first resistance element (29) and the second resistance element (27, 28) is arranged upstream or downstream of the heating element (26); processing the heating power signal into a heating power (PH), the first temperature signal into a first temperature (TM), and the second temperature signal into a second temperature (TD, TU);Calculating a difference (ΔTD, ΔTU, ΔTDU) between the first and second temperatures; determining a temperature-compensated heating power from the processed heating power (PH) and a temperature-compensated difference from the calculated difference (ΔTD, ΔTU, ΔTDU); and estimating the type of fuel (6) and / or the type of fuel gas (6) in the combustion device (1) as a function of the temperature-compensated heating power and the temperature-compensated difference.

[0137] The mass flow sensor (11) is preferably in contact with the fuel (6) and / or with the fuel gas (6).

[0138] The method for estimating the type of fuel (6) and / or the type of fuel gas (6) in a combustion device (1) with a mass flow sensor (11) is preferably a method for determining the type of fuel (6) and / or the type of fuel gas (6) in a combustion device (1) with a mass flow sensor (11). Accordingly, the method comprises the step of determining the type of fuel (6) and / or the type of fuel gas (6) in the combustion device (1) as a function of the temperature-compensated heating power and the temperature-compensated difference. The method for estimating the type of fuel (6) and / or the type of fuel gas (6) in a combustion device (1) with a mass flow sensor (11) is preferably a method for calculating the type of fuel (6) and / or the type of fuel gas (6) in a combustion device (1) with a mass flow sensor (11).Accordingly, the procedure includes the step of calculating the type of fuel (6) and / or the type of fuel gas (6) in the combustion device (1) as a function of the temperature-compensated heating power and the temperature-compensated difference.

[0139] The present disclosure further relates to one of the aforementioned methods, comprising the step of recording a second temperature signal, which indicates a second temperature of the fuel (6) and / or the fuel gas (6), using a second resistance element (27, 28) of the mass flow sensor (11), wherein the second resistance element (27, 28) is arranged upstream or downstream of the heating element (26), wherein a supply of the fuel (6) and / or the fuel gas (6) to the combustion device (1) defines a flow direction. The second temperature signal is preferably recorded simultaneously or substantially simultaneously with the first temperature signal.

[0140] The present disclosure further concerns one of the aforementioned procedures, the procedure comprising the steps: Determining the temperature-compensated heating power from the processed heating power (PH) using a first, empirically determined calibration characteristic curve and / or using a first, empirically determined calibration function; and determining the temperature-compensated difference from the calculated difference (ΔTD, ΔTU, ΔTDU) using a second, empirically determined calibration characteristic curve.

[0141] The present disclosure also concerns one of the aforementioned procedures, the procedure comprising the following steps: Determining a first difference value of the determined temperature-compensated difference from a temperature-compensated difference specified for a first fuel (6) and / or for a first fuel gas (6); Determining a second difference value of the determined temperature-compensated heating output from a temperature-compensated heating output specified for the first fuel (6) and / or for the first fuel gas (6); Determining a third difference value of the determined temperature-compensated difference from a temperature-compensated difference specified for a second fuel (6) and / or for a second fuel gas (6); Determining a fourth difference value of the determined temperature-compensated heating output from a temperature-compensated heating output specified for the second fuel (6) and / or for the second fuel gas (6); Determining a first interval between the first and the second difference value;Determine a second distance between the third and fourth difference values; and if the first distance is smaller than the second distance: Estimate the type of fuel (6) and / or the type of fuel gas (6) in the combustion device (1) as the first fuel (6) and / or as the first fuel gas (6).

[0142] The present disclosure also relates to one of the aforementioned methods including a first difference value, the method comprising the step: if the first distance is smaller than the second distance: determining the type of fuel (6) and / or the type of fuel gas (6) in the combustion device (1) as the first fuel (6) and / or as the first fuel gas (6).

[0143] The present disclosure also relates to one of the aforementioned methods involving a first difference value, the method comprising the step: if the second distance is smaller than the first distance: estimating the type of fuel (6) and / or the type of fuel gas (6) in the combustion device (1) as the second fuel (6) and / or as the second fuel gas (6).

[0144] The present disclosure further relates to one of the aforementioned methods, including a first difference value, the method comprising the following steps: Calculating a first difference value of the determined temperature-compensated difference from a temperature-compensated difference specified for a first fuel (6) and / or for a first fuel gas (6); calculating a second difference value of the determined temperature-compensated heating output from a temperature-compensated heating output specified for the first fuel (6) and / or for the first fuel gas (6); calculating a third difference value of the determined temperature-compensated difference from a temperature-compensated difference specified for a second fuel (6) and / or for a second fuel gas (6); and calculating a fourth difference value of the determined temperature-compensated heating output from a temperature-compensated heating output specified for the second fuel (6) and / or for the second fuel gas (6).

[0145] The present disclosure further relates to one of the aforementioned methods including a first difference value, the method additionally comprising the step: comparing the first distance with the second distance.

[0146] The present disclosure further relates to one of the aforementioned methods including a first difference value, the method additionally comprising the step: numerically comparing the first distance with the second distance.

[0147] The present disclosure also relates to one of the aforementioned methods including a first difference value, the method comprising the step: if the second distance is smaller than the first distance: determining the type of fuel (6) and / or the type of fuel gas (6) in the combustion device (1) as the second fuel (6) and / or as the second fuel gas (6).

[0148] The present disclosure also concerns one of the aforementioned procedures, the procedure comprising the following steps: Assigning the estimated type of fuel (6) and / or fuel gas (6) to a minimum air requirement (Lmin); and controlling at least one air actuator (3, 4) of the combustion device (1) depending on the assigned minimum air requirement (Lmin).

[0149] The present disclosure also relates to one of the aforementioned methods, the method additionally comprising the step: controlling at least one air actuator (3, 4) of the combustion device (1) to the associated minimum air requirement (Lmin).

[0150] The present disclosure further concerns one of the aforementioned procedures, the procedure additionally comprising the following steps: Assigning the specific type of fuel (6) and / or fuel gas (6) to a minimum air requirement (Lmin); and controlling at least one air actuator (3, 4) of the combustion device (1) depending on the assigned minimum air requirement (Lmin).

[0151] The present disclosure relates to one of the aforementioned procedures, the procedure additionally encompassing the following steps: Assigning the calculated type of fuel (6) and / or fuel gas (6) to a minimum air requirement (Lmin); and controlling at least one air actuator (3, 4) of the combustion device (1) depending on the assigned minimum air requirement (Lmin).

[0152] The present disclosure further concerns one of the aforementioned procedures, the procedure additionally comprising the following steps: Assigning the specific type of fuel (6) and / or fuel gas (6) to a minimum air requirement (Lmin); and controlling at least one air actuator (3, 4) of the combustion device (1) to the assigned minimum air requirement (Lmin).

[0153] The present disclosure relates to one of the aforementioned procedures, the procedure additionally encompassing the following steps: Assigning the calculated type of fuel (6) and / or fuel gas (6) to a minimum air requirement (Lmin); and controlling at least one air actuator (3, 4) of the combustion device (1) to the assigned minimum air requirement (Lmin).

[0154] The present disclosure further addresses one of the aforementioned procedures, the procedure comprising the steps: Assigning the estimated type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); determining a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) using at least one air actuator (3, 4) of the combustion device (1) or using at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

[0155] The air supply (5) is preferably an air supply (5) to a combustion chamber (2) of the combustion device (1).

[0156] The present disclosure also covers one of the aforementioned procedures, the procedure comprising the steps: Assigning the specific type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); determining a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) using at least one air actuator (3, 4) of the combustion device (1) or using at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

[0157] The present disclosure further addresses one of the aforementioned procedures, the procedure comprising the steps: Assigning the calculated type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); determining a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) using at least one air actuator (3, 4) of the combustion device (1) or using at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

[0158] The present disclosure also covers one of the aforementioned procedures, the procedure comprising the steps: Assigning the estimated type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); calculating a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) using at least one air actuator (3, 4) of the combustion device (1) or using at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

[0159] The present disclosure further addresses one of the aforementioned procedures, the procedure comprising the steps: Assigning the specific type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); calculating a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) using at least one air actuator (3, 4) of the combustion device (1) or using at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

[0160] The present disclosure further addresses one of the aforementioned procedures, the procedure comprising the steps: Assigning the calculated type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); calculating a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) using at least one air actuator (3, 4) of the combustion device (1) or using at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

[0161] The present disclosure further addresses one of the aforementioned procedures, the procedure comprising the steps: Correcting an operating characteristic curve based on the estimated type of fuel (6) and / or based on the estimated type of fuel gas (6), wherein the operating characteristic curve is selected from: a first operating characteristic curve between temperature-compensated heating output and fuel supply (16) and / or fuel gas supply (16), or a second operating characteristic curve between temperature-compensated difference and fuel supply (16) and / or fuel gas supply (16); determining a current fuel supply and / or a current fuel gas supply based on the corrected operating characteristic curve and based on a further quantity selected from: the temperature-compensated heating output, or the temperature-compensated difference; and controlling at least one fuel actuator (7, 8) of the combustion device (1) depending on the current fuel supply and / or the current fuel gas supply.

[0162] Preferably, the next size up is selected from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0163] Ideally, the next size up should be selected exclusively from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0164] The present disclosure further addresses one of the aforementioned procedures, the procedure comprising the steps: Assigning the estimated type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); correcting an operating characteristic curve based on the assigned calorific value (Hu), wherein the operating characteristic curve is selected from: a first operating characteristic curve between temperature-compensated heating output and fuel supply (16) and / or fuel gas supply (16), or a second operating characteristic curve between temperature-compensated difference and fuel supply (16) and / or fuel gas supply (16); determining a current fuel supply and / or a current fuel gas supply based on the corrected operating characteristic curve and based on a further quantity selected from: the temperature-compensated heating output, or the temperature-compensated difference; and controlling at least one fuel actuator (7, 8) of the combustion device (1) depending on the current fuel supply and / or the current fuel gas supply.

[0165] Preferably, the next size up is selected from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0166] Ideally, the next size up should be selected exclusively from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0167] The present disclosure also relates to a combustion device (1) comprising a combustion chamber (2), a fuel supply channel for supplying a fuel (6) and / or fuel gas (6) to the combustion chamber (2), a mass flow sensor (11) in or on the fuel supply channel and a control and / or regulating unit (13) in communicative connection with the mass flow sensor (11), wherein the mass flow sensor (11) comprises a heating element (26), a first resistance element (29) and a second resistance element (27, 28), wherein the second resistance element (27, 28) is different from the first resistance element (29), wherein the control and / or regulating unit (13) is configured as follows: to record a heating power signal indicating the heating power of the heating element (26) of the mass flow sensor (11); to record a first temperature signal indicating a first temperature of the fuel (6) and / or the fuel gas (6) using the first resistance element (29) of the mass flow sensor (11); to record a second temperature signal indicating a second temperature of the fuel (6) and / or the fuel gas (6) using the second resistance element (27, 28); to process the heating power signal into a heating power (PH), the first temperature signal into a first temperature (TM), and the second temperature signal into a second temperature (TD, TU); to calculate a difference (ΔTD, ΔTU, ΔTDU) between the first and second temperatures; to determine a temperature-compensated heating power from the processed heating power (PH) and a temperature-compensated difference from the calculated difference (ΔTD, ΔTU,ΔTDU);and to estimate a type of fuel (6) and / or fuel gas (6) as a function of the temperature-compensated heating power and the temperature-compensated difference.

[0168] The mass flow sensor (11) is preferably in contact with the fuel (6) and / or the fuel gas (6). Ideally, the mass flow sensor (11) is in fluid communication with the fuel (6) and / or the fuel gas (6).

[0169] The present disclosure further relates to one of the aforementioned combustion devices (1), wherein a supply of fuel (6) and / or fuel gas (6) through the fuel supply channel towards the combustion chamber (2) defines a flow direction; and wherein the second resistance element (27, 28) is arranged upstream or downstream of the heating element (26).

[0170] The second temperature signal is preferably recorded simultaneously or substantially simultaneously with the first temperature signal.

[0171] It is intended that the type of fuel (6) and / or fuel gas (6) be determined. It is further intended that the type of fuel (6) and / or fuel gas (6) be calculated.

[0172] The present disclosure also relates to one of the aforementioned combustion devices (1), wherein the control and / or regulating unit (13) has a non-volatile memory and a first empirically determined calibration characteristic curve is stored in the non-volatile memory of the control and / or regulating unit (13), wherein the control and / or regulating unit (13) is configured as follows: to read the first empirically determined calibration curve from the non-volatile memory; and to determine the temperature-compensated heating power from the processed heating power (PH) based on the first empirically determined calibration curve.

[0173] The present disclosure further relates to one of the aforementioned combustion devices (1), wherein the control and / or regulating unit (13) has a non-volatile memory and a second, empirically determined calibration characteristic is stored in the non-volatile memory of the control and / or regulating unit (13), wherein the control and / or regulating unit (13) is configured as follows: to read the second, empirically determined calibration curve from the non-volatile memory; and to determine the temperature-compensated difference from the calculated difference (ΔTD, ΔTU, ΔTDU) using the second, empirically determined calibration curve.

[0174] The present disclosure further relates to one of the aforementioned combustion devices (1), wherein the control and / or regulating unit (13) has a non-volatile storage device and a first temperature-compensated difference predetermined for a first fuel (6) and / or for a first fuel gas (6) is stored in the non-volatile storage device of the control and / or regulating unit (13), and a second temperature-compensated difference predetermined for a second fuel (6) and / or for a second fuel gas (6) is stored in the non-volatile storage device of the control and / or regulating unit (13), and a first temperature-compensated heating power predetermined for the first fuel (6) and / or for the first fuel gas (6) is stored in the non-volatile storage device of the control and / or regulating unit (13), and a second temperature-compensated heating power predetermined for the first fuel (6) and / or for the first fuel gas (6) is stored in the non-volatile storage device of the control and / or regulating unit (13).a temperature-compensated heating output is stored for the second fuel (6) and / or for the second fuel gas (6), wherein the control and / or regulating unit (13) is configured as follows: , to determine a first difference value of the determined temperature-compensated difference from the first, predetermined temperature-compensated difference; to determine a second difference value of the determined temperature-compensated heating output from the first, predetermined temperature-compensated heating output; to determine a third difference value of the determined temperature-compensated difference from the second, predetermined temperature-compensated difference; to determine a fourth difference value of the determined temperature-compensated heating output from the second, predetermined temperature-compensated heating output; to determine a first distance between the first and the second difference value; to determine a second distance between the third and the fourth difference value; and if the first distance is smaller than the second distance: to estimate the type of fuel (6) and / or fuel gas (6) as the first fuel (6) and / or as the first fuel gas (6).

[0175] The present disclosure also relates to one of the aforementioned combustion devices (1) including a first difference value, wherein the control and / or regulating unit (13) is configured: when the first distance is smaller than the second distance: to determine the type of fuel (6) and / or fuel gas (6) as the first fuel (6) and / or fuel gas (6).

[0176] The present disclosure further relates to one of the aforementioned combustion devices (1) including a first difference value, wherein the control and / or regulating unit (13) is configured: if the second distance is smaller than the first distance: to estimate the type of fuel (6) and / or fuel gas (6) as the second fuel (6) and / or as the second fuel gas (6).

[0177] The first distance is preferably a first distance measurement. The second distance is preferably a second distance measurement.

[0178] The present disclosure further relates to one of the aforementioned combustion devices (1) including a first difference value, wherein the control and / or regulating unit (13) is configured: to calculate a first difference value of the determined temperature-compensated difference from the first, specified temperature-compensated difference; to calculate a second difference value of the determined temperature-compensated heating output from the first, specified temperature-compensated heating output; to calculate a third difference value of the determined temperature-compensated difference from the second, specified temperature-compensated difference; and to calculate a fourth difference value of the determined temperature-compensated heating output from the second, specified temperature-compensated heating output.

[0179] In one embodiment, the first distance is determined by adding the first and second difference values. Similarly, the second distance is determined by adding the third and fourth difference values. Ideally, the first distance is calculated by adding the first and second difference values. Similarly, the second distance is calculated by adding the third and fourth difference values.

[0180] In another embodiment, the first distance is determined as a function of the square of the first difference value and as a function of the square of the second difference value. Similarly, the second distance is determined as a function of the square of the third difference value and as a function of the square of the fourth difference value. Ideally, the first distance is calculated as a function of the square of the first difference value and as a function of the square of the second difference value. Similarly, the second distance is calculated as a function of the square of the third difference value and as a function of the square of the fourth difference value.

[0181] Preferably, the first distance is calculated as the square root of a first sum, where the first sum is calculated by adding the square of the first difference value and the square of the second difference value. Similarly, the second distance is calculated as the square root of a second sum, where the second sum is calculated by adding the square of the third difference value and the square of the fourth difference value. Ideally, the first distance is calculated as the square root of a first sum, where the first sum is calculated by adding the square of the first difference value and the square of the second difference value. Similarly, the second distance is calculated as the square root of a second sum, where the second sum is calculated by adding the square of the third difference value and the square of the fourth difference value.

[0182] The first fuel (6) and / or the first fuel gas (6) is preferably a first predetermined fuel (6) and / or a first predetermined fuel gas (6). The second fuel (6) and / or the second fuel gas (6) is preferably a second predetermined fuel (6) and / or a second predetermined fuel gas (6).

[0183] The present disclosure further relates to one of the aforementioned combustion devices (1) including a first difference value, wherein the control and / or regulating unit (13) is configured to compare the first distance with the second distance.

[0184] The present disclosure also relates to one of the aforementioned combustion devices (1) including a first difference value, wherein the control and / or regulating unit (13) is configured to numerically compare the first distance with the second distance.

[0185] The present disclosure also relates to one of the aforementioned combustion devices (1) including a first difference value, wherein the control and / or regulating unit (13) is configured: when the second distance is smaller than the first distance: to determine the type of fuel (6) and / or fuel gas (6) as the second fuel (6) and / or as the second fuel gas (6).

[0186] The present disclosure further relates to one of the aforementioned combustion devices (1), wherein the combustion device (1) comprises an air supply channel for an air supply (5) to the combustion chamber (2) and at least one air actuator (3, 4) acting on the air supply channel, wherein the control and / or regulating unit (13) is in communicative connection with the at least one air actuator (3, 4) and is configured as follows: to assign a minimum air requirement (Lmin) to the estimated type of fuel (6) and / or fuel gas (6); and to control the at least one air actuator (3, 4) depending on the assigned minimum air requirement (Lmin).

[0187] The present disclosure also relates to one of the aforementioned combustion devices (1) incorporating an air supply channel, wherein the control and / or regulating unit (13) is configured to regulate the at least one air actuator (3, 4) to the associated minimum air requirement (Lmin).

[0188] The present disclosure further relates to one of the aforementioned combustion devices (1) incorporating an air supply channel, wherein the control and / or regulating unit (13) is configured as follows: to assign a minimum air requirement (Lmin) to the specific type of fuel (6) and / or fuel gas (6); and to control the at least one air actuator (3, 4) depending on the assigned minimum air requirement (Lmin).

[0189] The present disclosure further relates to one of the aforementioned combustion devices (1) incorporating an air supply channel, wherein the control and / or regulating unit (13) is configured as follows: to assign a minimum air requirement (Lmin) to the calculated type of fuel (6) and / or fuel gas (6); and to control the at least one air actuator (3, 4) depending on the assigned minimum air requirement (Lmin).

[0190] The present disclosure further relates to one of the aforementioned combustion devices (1) incorporating an air supply channel, wherein the control and / or regulating unit (13) is configured as follows: to assign a minimum air requirement (Lmin) to the specific type of fuel (6) and / or fuel gas (6); and to control the at least one air actuator (3, 4) to the assigned minimum air requirement (Lmin).

[0191] The present disclosure further relates to one of the aforementioned combustion devices (1) incorporating an air supply channel, wherein the control and / or regulating unit (13) is configured as follows: to assign a minimum air requirement (Lmin) to the calculated type of fuel (6) and / or fuel gas (6); and to control the at least one air actuator (3, 4) to the assigned minimum air requirement (Lmin).

[0192] The present disclosure further relates to one of the aforementioned combustion devices (1), wherein the combustion device (1) comprises a fuel supply channel for a fuel supply and / or a fuel gas supply to the combustion chamber (2) and at least one fuel actuator (7, 8) acting on the fuel supply channel, wherein the control and / or regulating unit (13) is in communicative connection with the at least one fuel actuator (7, 8) and is configured as follows: to correct an operating characteristic curve based on the estimated type of fuel (6) and / or based on the estimated type of fuel gas (6), wherein the operating characteristic curve is selected from: a first operating characteristic curve between temperature-compensated heating output and fuel supply (16) and / or fuel gas supply (16), or a second operating characteristic curve between temperature-compensated difference and fuel supply (16) and / or fuel gas supply (16); an actual fuel supply and / or an actual fuel gas supply based on the corrected operating characteristic curve and based on a further quantity selected from: the temperature-compensated heating output, or the temperature-compensated difference to determine; and to control at least one fuel actuator (7, 8) depending on the current fuel supply and / or the current fuel gas supply.

[0193] Preferably, the next size up is selected from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0194] Ideally, the next size up should be selected exclusively from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0195] Advantageously, the fuel supply channel includes a fuel gas supply channel. Ideally, the fuel supply channel is a fuel gas supply channel.

[0196] The present disclosure further relates to one of the aforementioned combustion devices (1), wherein the combustion device (1) comprises a fuel supply channel for a fuel supply and / or a fuel gas supply to the combustion chamber (2) and at least one fuel actuator (7, 8) acting on the fuel supply channel, wherein the control and / or regulating unit (13) is in communicative connection with the at least one fuel actuator (7, 8) and is configured as follows: to assign a calorific value (Hu) to the estimated type of fuel (6) and / or the estimated type of fuel gas (6); to correct an operating characteristic curve based on the assigned calorific value (Hu), wherein the operating characteristic curve is selected from: a first operating characteristic curve between temperature-compensated heating output and fuel supply (16) and / or fuel gas supply (16), or a second operating characteristic curve between temperature-compensated difference and fuel supply (16) and / or fuel gas supply (16);

[0197] Determining a current fuel supply and / or a current fuel gas supply based on the corrected operating characteristic curve and on another parameter selected from: the temperature-compensated heating output, or the temperature-compensated difference; and to control at least one fuel actuator (7, 8) depending on the current fuel supply and / or the current fuel gas supply.

[0198] Preferably, the next size up is selected from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0199] Ideally, the next size up should be selected exclusively from: the temperature-compensated heating output in the case of selecting the first operating characteristic as the operating characteristic, or the temperature-compensated difference in the case of selecting the second operating characteristic as the operating characteristic.

[0200] Advantageously, the fuel supply channel includes a fuel gas supply channel. Ideally, the fuel supply channel is a fuel gas supply channel.

[0201] The present disclosure also relates to a computer program product comprising instructions that cause one of the aforementioned combustion devices (1) to perform one of the aforementioned methods.

[0202] The present disclosure also relates to a computer program product comprising instructions that cause one of the aforementioned combustion devices (1) with stored heating capacities for first and second fuels to perform one of the aforementioned methods taking into account one or more distances.

[0203] The present disclosure further teaches a method for estimating a flow rate (25) for fuels (6) and / or fuel gases (6) of different compositions supplied to a combustion device (1) via a fuel supply channel and / or fuel gas supply channel, wherein the combustion device (1) comprises a mass flow sensor (11), wherein the mass flow sensor (11) is in fluid communication with the fuel (6) and / or with the fuel gas (6), the method comprising the steps: Recording a first temperature signal, indicating a first temperature of the fuel (6) and / or the fuel gas (6), using a first resistance element (29) of the mass flow sensor (11); processing the first temperature signal to obtain a first temperature (TM); determining a compensable value either by recording a heating power signal, indicating a heating power of a heating element (26) of the mass flow sensor (11); processing the heating power signal to obtain a heating power; determining the compensable value as heating power;or by recording a second temperature signal indicating a second temperature of the fuel (6) and / or the fuel gas (6) using a second resistive element (27, 28) of the mass flow sensor (11) and / or recording a third temperature signal indicating a third temperature of the fuel (6) and / or the fuel gas (6) using a third resistive element (28, 27) of the mass flow sensor (11), wherein the second and / or the third resistive element is different from the first resistive element (29); processing the second temperature signal to a second temperature (TD, TU) and / or the third temperature signal to a third temperature (TU, TD); determining the compensable value as the first temperature difference (ΔTD, ΔTU, ΔTDU) between two different, preferably pairwise different, temperatures selected from: the first temperature (TM), the second temperature (TD, TU), the third temperature (TU, TD);and estimating a flow value (25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the value that can be compensated as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition using at least one stored mapping rule that depends on the first temperature (TM) and / or on the fuel composition and / or on the fuel gas composition, and using a calibration characteristic curve stored for a reference gas.

[0204] Preferably the second and / or the third resistance element is arranged upstream or downstream of one or the heating element (26).

[0205] In one embodiment, the first resistive element (29) of the mass flow sensor (11) comprises a first electrical resistance, for example, a first electrical ohmic resistance. In a particular embodiment, the first resistive element (29) of the mass flow sensor (11) is a first electrical resistance, for example, a first electrical ohmic resistance. In one embodiment, the second resistive element (27, 28) of the mass flow sensor (11) comprises a second electrical resistance, for example, a second electrical ohmic resistance. In a particular embodiment, the second resistive element (27, 28) of the mass flow sensor (11) is a second electrical resistance, for example, a second electrical ohmic resistance.In one embodiment, the third resistive element (28, 27) of the mass flow sensor (11) comprises a third electrical resistance, for example, a third electrical ohmic resistance. In a particular embodiment, the third resistive element (28, 27) of the mass flow sensor (11) is a third electrical resistance, for example, a third electrical ohmic resistance.

[0206] In particular, the present disclosure relates to an estimation of a flow value (25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensation of the as a function of the first temperature (TM) and as a function of at least one first quantity selected from: the fuel composition, the fuel gas composition, a compensable value based on at least one stored value selected from the first temperature (TM) and at least one second parameter: the fuel composition, the fuel gas composition dependent imaging rule and based on a calibration characteristic curve stored for a reference gas.

[0207] Furthermore, the present disclosure relates to an estimation of a flow value (25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensation of the value selected as a function of the first temperature (TM) and as a function of at least one first quantity exclusively from: the fuel composition, the fuel gas composition, a compensable value based on at least one stored value selected from the first temperature (TM) and at least one second parameter, exclusively from: the fuel composition, the fuel gas composition dependent imaging rule and based on a calibration characteristic curve stored for a reference gas.

[0208] The present disclosure further relates to one of the aforementioned methods comprising the step of determining the compensable value as the first temperature difference (ΔTD, ΔTU,ΔTDU) between the first (TM) and the second temperature (TD, TU) or as the temperature difference (ΔTD, ΔTU,ΔTDU) between the second and the third temperature (TU, TD).

[0209] The present disclosure further relates to one of the aforementioned methods, comprising the step of determining the compensable value as the first temperature difference (ΔTD, ΔTU, ΔTDU) between two different, preferably pairwise different, temperatures selected exclusively from: the first temperature (TM), the second temperature (TD, TU), the third temperature (TU, TD).

[0210] In the context of this revelation, an exclusive function is one that depends solely on the arguments mentioned. This means that the list of arguments for a given function is exhaustive. The same applies to an exclusive selection.

[0211] The present disclosure teaches one of the aforementioned methods, wherein the reference gas for the calibration characteristic is methane gas. Advantageously, a flow value (25) of the fuel supply (6) and / or the fuel gas supply (6) is estimated.

[0212] The present disclosure further teaches one of the aforementioned methods, wherein the reference gas for the calibration characteristic is air.

[0213] The present disclosure further teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13), the method comprising the step: storing the calibration characteristic in the control and / or regulating unit (13).

[0214] The present disclosure also teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13) with an operating unit and wherein a plurality of first temperature (TM) dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6) is stored in the control and / or regulating unit (13), the method comprising the step: when setting the combustion device (1), selecting the stored first temperature (TM) dependent mapping rule from the plurality of mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) by means of the operating unit.

[0215] The present disclosure also teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13) with an operating unit and wherein a plurality of first temperature (TM) dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6) is stored in the control and / or regulating unit (13), the method comprising the step: when starting up the combustion device (1), selecting the stored first temperature (TM) dependent mapping rule from the plurality of mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) by means of the operating unit.

[0216] The present disclosure also teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13) with an operating unit and wherein a plurality of first temperature (TM) dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6) is stored in the control and / or regulating unit (13), the method comprising the step: during maintenance of the combustion device (1), selecting during adjustment of the combustion device (1) the stored first temperature (TM) dependent mapping rule from the plurality of mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) by means of the operating unit.

[0217] It is intended that the dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) each include a stored calibration characteristic curve and / or a model function.

[0218] The present disclosure also teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13) and the control and / or regulating unit (13) contains a plurality of first temperature-dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6), and a plurality of second temperature-dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6), the method comprising the steps: Recording the heating power signal, which indicates a heating power of a heating element (26) of the mass flow sensor (11); processing the heating power signal to obtain the heating power; determining a plurality of first estimated flow values ​​(25) for the fuel supply and / or for the fuel gas supply by compensating the heating power as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition using at least one mapping rule from the plurality of first stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and using a first stored calibration characteristic curve; recording a second temperature signal and / or a third temperature signal; processing the second temperature signal to obtain a second temperature (TD, TU) and / or the third temperature signal to obtain a third temperature (TU, TD);Determining the temperature difference (ΔTD, ΔTU, ΔTDU) between two different temperatures selected from: the first temperature (TM), the second temperature (TD, TU), the third temperature (TU, TD); determining a plurality of second estimated flow values ​​(25) for the fuel supply and / or for the fuel gas supply by compensating the temperature difference (ΔTD, ΔTU, ΔTDU) as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition using at least one mapping rule from the plurality of second stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and using a second stored calibration curve; and estimating the type of fuel (6) and / or fuel gas (6) using the plurality of first estimated flow values ​​(25) and using the plurality of second estimated flow values ​​(25).

[0219] The present disclosure further teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13) and the control and / or regulating unit (13) contains a plurality of first temperature-dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6), and a plurality of second temperature-dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6), the method comprising the steps: Recording the heating power signal, which indicates a heating power of a heating element (26) of the mass flow sensor (11); processing the heating power signal to obtain the heating power; determining a plurality of first estimated flow values ​​(25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the heating power as a function of the first temperature (TM) and as a function of the fuel composition and / or as a function of the fuel gas composition using at least one mapping rule from the plurality of first stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and using a first stored calibration characteristic curve; recording the second temperature signal and / or the third temperature signal; processing the second temperature signal to obtain a second temperature (TD, TU) and / or the third temperature signal to obtain a third temperature (TU, TD);Determining the temperature difference (ΔTD, ΔTU, ΔTDU) between two different temperatures selected from: the first temperature (TM), the second temperature (TD, TU), the third temperature (TU, TD); determining a plurality of second estimated flow values ​​(25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the temperature difference (ΔTD, ΔTU, ΔTDU) as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition using at least one mapping rule of the plurality of second stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and using a second stored calibration curve; and estimating the type of fuel (6) and / or fuel gas (6) using the plurality of first estimated flow values ​​(25) and using the plurality of second estimated flow values ​​(25). ;

[0220] In particular, it may be possible to obtain a variety of second estimated flow values ​​(25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the temperature difference (ΔTD, ΔTU, ΔTDU) as a function of the first temperature (TM) and as a function of a third quantity selected from: the fuel composition, the fuel gas composition to be determined on the basis of at least one of the multiple second, stored imaging rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and on the basis of a second, stored calibration characteristic curve.

[0221] The present disclosure further teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13) and the control and / or regulating unit (13) contains a plurality of first temperature-dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6), and a plurality of second temperature-dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6), the method comprising the steps: Recording the heating power signal, which indicates a heating power of a heating element (26) of the mass flow sensor (11); processing the heating power signal to obtain the heating power; determining a plurality of first estimated flow values ​​(25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the heating power as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition based on each mapping rule of the plurality of first stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and based on a first stored calibration characteristic; recording the second temperature signal and / or the third temperature signal; processing the second temperature signal to obtain a second temperature (TD, TU) and / or the third temperature signal to obtain a third temperature (TU, TD);Determining the temperature difference (ΔTD, ΔTU, ΔTDU) between two different temperatures selected from: the first temperature (TM), the second temperature (TD, TU), the third temperature (TU, TD); determining a plurality of second estimated flow values ​​(25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the temperature difference (ΔTD, ΔTU, ΔTDU) as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition using each mapping rule of the plurality of second stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and using a second stored calibration curve; and estimating the type of fuel (6) and / or fuel gas (6) using the plurality of first estimated flow values ​​(25) and using the plurality of second estimated flow values ​​(25). ;

[0222] Preferably, the aforementioned method comprises the step of determining the temperature difference (ΔTD, ΔTU, ΔTDU) between two different temperatures selected exclusively from: the first temperature (TM), the second temperature (TD, TU), the third temperature (TU, TD).

[0223] The present disclosure also teaches one of the aforementioned methods involving a fuel estimation and / or fuel gas estimation, the method comprising the steps: Forming distances between flow values ​​of the plurality of first estimated flow values ​​(25) and the plurality of second estimated flow values ​​(25); selecting a smallest distance from the formed distances; and estimating the type of fuel (6) and / or fuel gas (6) by assigning the smallest distance to a fuel (6) and / or fuel gas (6).

[0224] Preferably, the distances formed are differences formed or amounts of differences formed.

[0225] The present disclosure further teaches one of the aforementioned methods incorporating a fuel estimation and / or fuel gas estimation, the method comprising the steps: Forming differences between flow values ​​of the plurality of first estimated flow values ​​(25) and the plurality of second estimated flow values ​​(25); selecting the smallest difference from the formed differences; and estimating the type of fuel (6) and / or fuel gas (6) by assigning the smallest difference to a fuel (6) and / or fuel gas (6).

[0226] The present disclosure further teaches one of the aforementioned methods involving a fuel estimation and / or fuel gas estimation, wherein a plurality of third first temperature (TM) dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6) is stored in the control and / or regulating unit (13), the method comprising the steps: Recording a fourth temperature signal, indicating a fourth temperature of the fuel (6) and / or the fuel gas (6), using a fourth resistive element (28, 27) of the mass flow sensor (11), wherein the fourth resistive element (28, 27) is different from the first resistive element (29) and the second resistive element (27, 28) and wherein the fourth resistive element (28, 27) is arranged upstream or downstream of the heating element (26) opposite to the second resistive element (27, 28); processing the fourth temperature signal to a fourth temperature (TU, TD); calculating a second temperature difference (ΔTD, ΔTU, ΔTDU) between two different, preferably pairwise different, temperatures selected from: the first temperature (TM), the second temperature (TD, TU), the fourth temperature (TU, TD);Determining a plurality of third estimated flow values ​​(25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the second temperature difference (ΔTD, ΔTU, ΔTDU) as a function of the first temperature (TM) and / or as a function of the fuel composition and / or as a function of the fuel gas composition using at least one mapping rule of the plurality of third, stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and using a third, stored calibration curve; Estimating the type of fuel (6) and / or fuel gas (6) using the plurality of first estimated flow values ​​(25) and using the plurality of second estimated flow values ​​(25) and / or using the plurality of third estimated flow values ​​(25).

[0227] Preferably, the aforementioned method comprises the step of calculating a second temperature difference (ΔTD, ΔTU, ΔTDU) between two different, preferably pairwise different, temperatures selected exclusively from: the first temperature (TM), the second temperature (TD, TU), the fourth temperature (TU, TD);

[0228] In one embodiment, the fourth resistive element (28, 27) of the mass flow sensor (11) comprises a fourth electrical resistor, for example, a fourth electrical ohmic resistor. In a particular embodiment, the fourth resistive element (28, 27) of the mass flow sensor (11) is a fourth electrical resistor, for example, a fourth electrical ohmic resistor.

[0229] Furthermore, the fourth temperature signal can be the same as the third temperature signal. Conversely, the fourth temperature signal and the third temperature signal can also be different.

[0230] The present disclosure further teaches one of the aforementioned methods involving a fuel estimation and / or fuel gas estimation, wherein a plurality of third first temperature (TM) dependent mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuels (6) and / or for selectable fuel gases (6) is stored in the control and / or regulating unit (13), the method comprising the steps: Recording a fourth temperature signal, indicating a fourth temperature of the fuel (6) and / or the fuel gas (6), using a fourth resistive element (28, 27) of the mass flow sensor (11), wherein the fourth resistive element (28, 27) is different from the first resistive element (29) and the second resistive element (27, 28) and wherein the fourth resistive element (28, 27) is arranged upstream or downstream of the heating element (26) opposite to the second resistive element (27, 28); processing the fourth temperature signal to a fourth temperature (TU, TD); calculating a second temperature difference (ΔTD, ΔTU, ΔTDU) between two different, preferably pairwise different, temperatures selected from: the first temperature (TM), the second temperature (TD, TU), the fourth temperature (TU, TD);Determining a plurality of third estimated flow values ​​(25) for the fuel supply (6) and / or for the fuel gas supply (6) by compensating the second temperature difference (ΔTD, ΔTU, ΔTDU) as a function of the first temperature (TM) and / or of the fuel composition and / or of the fuel gas composition using each mapping rule of the plurality of third stored mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and using a third stored calibration curve; and estimating the type of fuel (6) and / or fuel gas (6) using the plurality of first estimated flow values ​​(25) and using the plurality of second estimated flow values ​​(25) and using the plurality of third estimated flow values ​​(25).

[0231] Preferably, the aforementioned method comprises the step of calculating a second temperature difference (ΔTD, ΔTU, ΔTDU) between two different, preferably pairwise different, temperatures selected exclusively from: the first temperature (TM), the second temperature (TD, TU), the fourth temperature (TU, TD).

[0232] The present disclosure also teaches one of the aforementioned methods involving a fuel estimation and / or fuel gas estimation, the method comprising the steps: Forming first differences between flow values ​​of the plurality of first estimated flow values ​​(25) and the plurality of second estimated flow values ​​(25); forming first squared differences by squaring the first differences; forming second differences between flow values ​​of the plurality of first estimated flow values ​​(25) and the plurality of third estimated flow values ​​(25); forming second squared differences by squaring the second differences; forming third differences between flow values ​​of the plurality of second estimated flow values ​​(25) and the plurality of third estimated flow values ​​(25); forming third squared differences by squaring the third differences;Forming sums by summing one first squared difference selected from the first squared differences formed, one second squared difference selected from the second squared differences formed, and one third squared difference selected from the third squared differences formed; selecting the smallest sum from the sums formed; and estimating the type of fuel (6) and / or fuel gas (6) by assigning the smallest sum to a fuel (6) and / or fuel gas (6).

[0233] The present disclosure further teaches one of the aforementioned methods incorporating a fuel estimation and / or fuel gas estimation, the method comprising the steps: Forming first distances between flow values ​​of the plurality of first estimated flow values ​​(25) and the plurality of second estimated flow values ​​(25); forming first squared distances by squaring the first distances; forming second distances between flow values ​​of the plurality of first estimated flow values ​​(25) and the plurality of third estimated flow values ​​(25); forming second squared distances by squaring the second distances; forming third distances between flow values ​​of the plurality of second estimated flow values ​​(25) and the plurality of third estimated flow values ​​(25); forming third squared distances by squaring the third distances;Forming sum values ​​by summing one first squared distance selected from the first squared distances formed, one second squared distance selected from the second squared distances formed, and one third squared distance selected from the third squared distances formed; selecting the smallest sum value from the sum values ​​formed; and estimating the type of fuel (6) and / or fuel gas (6) by assigning the smallest sum value to a fuel (6) and / or fuel gas (6).

[0234] In one embodiment, the first, second, and third distances are the first, second, and third differences. In another embodiment, the first, second, and third distances are the first, second, and third difference amounts.

[0235] The present disclosure further teaches one of the aforementioned methods involving a fuel estimation and / or fuel gas estimation, the method comprising the step: selection of a value as a measure of a fuel gas flow (6) from the plurality of first estimated flow values ​​(25) and from the plurality of second estimated flow values ​​(25).

[0236] The present disclosure further teaches the aforementioned method including a fuel estimation and / or fuel gas estimation, the method comprising the step: selection of a value as a measure of a fuel gas flow (6) from the plurality of first estimated flow values ​​(25) and from the plurality of second estimated flow values ​​(25) as a function of numerical values ​​of the first estimated flow values ​​(25) from the plurality of first estimated flow values ​​(25) and as a function of numerical values ​​of the second estimated flow values ​​(25) from the plurality of second estimated flow values ​​(25).

[0237] The present disclosure teaches one of the aforementioned methods, wherein the combustion device (1) comprises a control and / or regulating unit (13), the method comprising the step: storing the mapping rule dependent on the first temperature (TM) in the control and / or regulating unit (13).

[0238] The present disclosure further teaches one of the aforementioned methods incorporating a fuel estimation and / or fuel gas estimation, the method comprising the steps: Assigning the estimated type of fuel (6) and / or fuel gas (6) to a minimum air requirement (Lmin); and controlling at least one air actuator (3, 4) of the combustion device (1) depending on the assigned minimum air requirement (Lmin).

[0239] The present disclosure also teaches one of the aforementioned methods involving a fuel estimation and / or fuel gas estimation, the method comprising the steps: Assigning the estimated type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); determining a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) using at least one air actuator (3, 4) of the combustion device (1) or using at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

[0240] A correction of the air supply (5) of the combustion device (1) based on the at least one air actuator (3, 4) of the combustion device (1) in the ratio of the correction factor comprises a correction of the air supply (5) of the combustion device (1) based on the at least one air actuator (3, 4) of the combustion device (1) by forming a ratio, wherein the correction factor is included in the ratio. That is, the ratio formed is a function of the correction factor. The ratio can, in particular, be a quotient.

[0241] The present disclosure further teaches one of the aforementioned methods incorporating a fuel estimation and / or fuel gas estimation, the method comprising the steps: Correcting an operating characteristic curve based on the estimated type of fuel (6) and / or based on the estimated type of fuel gas (6), wherein the operating characteristic curve is selected from: a first operating characteristic curve between temperature-compensated heating output and fuel supply (16) and / or fuel gas supply (16), or a second operating characteristic curve between temperature-compensated difference and fuel supply (16) and / or fuel gas supply (16);

[0242] Determining a current fuel supply and / or a current fuel gas supply based on the corrected operating characteristic curve and on another parameter selected from: the temperature-compensated heating output, or the temperature-compensated difference; and

[0243] Control of at least one fuel actuator (7, 8) of the combustion device (1) depending on the current fuel supply and / or the current fuel gas supply.

[0244] The present disclosure further teaches one of the aforementioned methods incorporating a fuel estimation and / or fuel gas estimation, the method comprising the steps: Assigning the estimated type of fuel (6) and / or fuel gas (6) to a calorific value (Hu); Correcting an operating characteristic curve based on the assigned calorific value (Hu), wherein the operating characteristic curve is selected from: a first operating characteristic curve between temperature-compensated heating output and fuel supply (16) and / or fuel gas supply (16), or a second operating characteristic curve between temperature-compensated difference and fuel supply (16) and / or fuel gas supply (16); Determining a current fuel supply and / or a current fuel gas supply based on the corrected operating characteristic curve and based on a further quantity selected from: the temperature-compensated heating output, or the temperature-compensated difference; and

[0245] Control of at least one fuel actuator (7, 8) of the combustion device (1) depending on the current fuel supply and / or the current fuel gas supply.

[0246] The present disclosure further teaches a combustion device (1) comprising a combustion chamber (2), a fuel supply channel for supplying a fuel (6) and / or a fuel gas (6) to the combustion chamber (2), a mass flow sensor (11) in or on the fuel supply channel and a control and / or regulating unit (13) in communicative connection with the mass flow sensor (11); wherein the mass flow sensor (11) comprises a heating element (26), a first resistive element (29) and a second resistive element (27, 28) and / or a third resistive element (28, 27), wherein the second and / or the third resistive element is different from the first resistive element (29) and the second and / or the third resistive element is arranged upstream or downstream of the heating element (26); wherein the mass flow sensor (11) comprises a fourth resistive element (28, 27), wherein the fourth resistive element (28, 27) is different from the first resistive element (29) and from the second resistive element (27, 28); wherein the second resistive element (27, 28) and the fourth resistive element (28, 27) are arranged oppositely upstream or downstream with respect to the heating element (26); and wherein the control unit (13) is configured to perform one of the aforementioned procedures.

[0247] The present disclosure also teaches a combustion device (1) comprising a combustion chamber (2), a fuel supply channel for supplying a fuel (6) and / or a fuel gas (6) to the combustion chamber (2), a mass flow sensor (11) in or on the fuel supply channel and a control and / or regulating unit (13) in communicative connection with the mass flow sensor (11); wherein the mass flow sensor (11) comprises a heating element (26), a first resistive element (29) and a second resistive element (27, 28) different from the first resistive element (29) and arranged upstream or downstream from the heating element (26) and / or a third resistive element (28, 27) different from the first resistive element (29) and arranged upstream or downstream from the heating element (26) and / or a fourth resistive element (28, 27) different from the first (29) and the second (27, 28) resistive elements and located upstream or downstream of the heating element (26) from the second resistive element (27, 28), wherein the control and / or regulating unit (13) is configured to carry out one of the aforementioned methods.

[0248] The present disclosure also teaches a combustion device (1) comprising a combustion chamber (2), a fuel supply channel for supplying a fuel (6) and / or a fuel gas (6) to the combustion chamber (2), a mass flow sensor (11) in or on the fuel supply channel and a control and / or regulating unit (13) in communicative connection with the mass flow sensor (11);wherein the mass flow sensor (11) comprises a heating element (26), a first resistive element (29) and a second resistive element (27, 28) different from the first resistive element (29) and arranged upstream or downstream of the heating element (26) and / or a third resistive element (28, 27) different from the first resistive element (29) and arranged upstream or downstream of the heating element (26) and / or a fourth resistive element (28, 27) different from the first (29) and the second (27, 28) resistive elements and arranged upstream or downstream opposite to the second resistive element (27, 28) with respect to the heating element (26), wherein the control and / or regulating unit (13) is configured to carry out one of the aforementioned methods.

[0249] The control and / or regulating units (13) of the aforementioned combustion devices (1) may include an operating unit, for example a screen and a keyboard. Such devices (1) are suitable, for example, for carrying out a process involving the operating unit.

[0250] In one embodiment, the fourth resistance element (28, 27) is identical to the third resistance element (28, 27). In another embodiment, the fourth resistance element (28, 27) and the third resistance element (28, 27) are different.

[0251] The present disclosure further teaches a computer program product comprising instructions that cause the aforementioned combustion device (1) to perform the process steps according to a aforementioned process.

[0252] The present disclosure also teaches a computer program product comprising instructions that cause the control and / or regulating unit (13) of one of the aforementioned combustion devices (1) to perform the process steps according to a aforementioned method.

[0253] The present disclosure also teaches a computer-readable medium on which the aforementioned computer program product is stored.

[0254] The above refers to individual embodiments of the disclosure. Various modifications to the embodiments can be made without deviating from the underlying idea and without leaving the scope of this disclosure. The subject matter of the present disclosure is defined by its claims. A wide variety of modifications can be made without leaving the scope of protection of the following claims. Reference sign

[0255] 1: Combustion device 2: Combustion chamber 3: Blower 4: Damper 5: Air supply 6: Fuel and / or fuel gas 7, 8: Fuel valves 9: Chimney 10: Air supply duct 11: Mass flow sensor 12: Measuring and control unit 13: Control and / or regulation unit 14: Control signal for air damper 15: Control signal for motor-driven blower 16: Differential temperature ΔTU 17: Differential temperature ΔTD or ΔTDU 18: Heating power PH of the mass flow sensor 19, 20: Control signals for motor-driven fuel valves 21: Sensor element 22: Thin layer and / or film 23, 24: Surfaces 25: Flow velocity 26 - 29: Resistor elements 30: Reference resistor 31: Series resistor 32: Sensor control unit 33: Driver 34 - 39: Electrical Voltages 40: Flow signal, calculated from ΔTU 41: Assignment, characteristic curve between ΔTU and fuel gas flow 42: Flow signal, calculated from ΔTD or ΔTDU 43: Flow signal, calculated from the heating power PH 44 - 48: Assignments,Characteristic curves between ΔTD / ΔTDU and fuel gas flow for different gas compositions 49 - 53: Assignments, characteristic curves between ΔTD / ΔTDU and fuel gas flow for different gas compositions,

Claims

1. Method for estimating a flow value (25) for fuel gases (6) of different compositions which are supplied to a combustion device (1) via a fuel gas supply channel, wherein the combustion device (1) comprises a mass flow sensor (11), wherein the mass flow sensor (11) is in fluid communication with the fuel gas (6), the method comprising the steps: recording a first temperature signal, which indicates a first temperature of the fuel gas (6), using a first resistor element (29) of the mass flow sensor (11); processing the first temperature signal to yield a first temperature (TM); determining a compensable value by recording a heat output signal, which indicates a heat output of a heating element (26) of the mass flow sensor (11); processing the heat output signal to yield a heat output; determining the compensable value as heat output; and estimating a flow value (25) for fuel gas supply by compensation of the value compensable as a function of the first temperature (TM) and as a function of the fuel gas composition on the basis of at least one saved mapping rule dependent on the first temperature (TM) and on the fuel gas composition and on the basis of a calibration characteristic curve saved for a reference gas.

2. The method according to claim 1, wherein the combustion device (1) comprises a closed- and / or open-loop control unit (13) and a plurality of first mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuel gases (6) and dependent on the first temperature (TM) and a plurality of second mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuel gases (6) and dependent on the first temperature (TM) are saved in the closed- and / or open-loop control unit (13), the method comprising the following steps: establishing a plurality of first estimated flow values (25) for the fuel gas supply by compensating the heat output as a function of the first temperature (TM) and as a function of the fuel gas composition, on the basis of at least one mapping rule of the plurality of first, saved mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and on the basis of a first, saved calibration characteristic curve; recording a second temperature signal and / or a third temperature signal; processing the second temperature signal to yield a second temperature (TD, TU) and / or the third temperature signal to yield a third temperature (TU, TD); determining the temperature difference (ΔTD,ΔTU,ΔTDU) between two different temperatures selected from: - the first temperature (TM), - the second temperature (TD, TU), - the third temperature (TU, TD); establishing a plurality of second estimated flow values (25) for the fuel gas supply by compensating the temperature difference (ΔTD,ΔTU,ΔTDU) as a function of the first temperature (TM) and as a function of the fuel gas composition, on the basis of at least one mapping rule of the plurality of second, saved mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and on the basis of a second, saved calibration characteristic curve; and estimating the type of fuel gas (6) on the basis of the plurality of first estimated flow values (25) and on the basis of the plurality of second estimated flow values (25).

3. The method according to claim 2, the method comprising the following steps: forming distances between flow values of the plurality of first estimated flow values (25) and the plurality of second estimated flow values (25); selecting the smallest distance from the distances formed; and estimating the type of fuel gas (6) by assigning the smallest distance to a fuel gas (6).

4. The method according to claim 2, wherein a plurality of third mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuel gases (6) and dependent on the first temperature (TM) are saved in the closed- and / or open-loop control unit (13), the method comprising the following steps: recording a fourth temperature signal, which indicates a fourth temperature of the fuel gas (6), on the basis of a fourth resistor element (28, 27) of the mass flow sensor (11), wherein the fourth resistor element (28, 27) is different from the first resistor element (29) and from the second resistor element (27, 28) and wherein the fourth resistor element (28, 27) is arranged opposite the second resistor element (27, 28) up- or downstream relative to the heating element (26); processing the fourth temperature signal to yield a fourth temperature (TU, TD); calculating a second temperature difference (ΔTD,ΔTU,ΔTDU) between two different temperatures, selected from: the first temperature (TM), the second temperature (TD, TU), the fourth temperature (TU, TD); establishing a plurality of third estimated flow values (25) for the fuel gas supply by compensating the second temperature difference (ΔTD,ΔTU,ΔTDU) as a function of the first temperature (TM) and as a function of the fuel gas composition, on the basis of at least one mapping rule of the plurality of third, saved mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) and on the basis of a third, saved calibration characteristic curve; and estimating the type of fuel gas (6) on the basis of the plurality of first estimated flow values (25) and on the basis of the plurality of second estimated flow values (25) and / or on the basis of the plurality of third estimated flow values (25).

5. The method according to claim 4, the method comprising the following steps: forming first distances between flow values of the plurality of first estimated flow values (25) and the plurality of second estimated flow values (25); forming first squared distances by squaring the first distances; forming second distances between flow values of the plurality of first estimated flow values (25) and the plurality of third estimated flow values (25); forming second squared distances by squaring the second distances; forming third distances between flow values of the plurality of second estimated flow values (25) and the plurality of third estimated flow values (25); forming third squared distances by squaring the third distances; forming sum values by summing in each case a first squared distance selected from the first squared distances formed, in each case a second squared distance selected from the second squared distances formed and in each case a third squared distance selected from the third squared distances formed; selecting the smallest sum value from the sum values formed; and estimating the type of fuel gas (6) by assigning the smallest sum value to a fuel gas (6).

6. The method according to one of claims 2 to 5, the method comprising the following step: selecting a value as a measure of a flow of the fuel gas (6) from the plurality of first estimated flow values (25) and from the plurality of second estimated flow values (25).

7. The method according to claim 6, the method comprising the following step: selecting a value as a measure of a flow of the fuel gas (6) from the plurality of first estimated flow values (25) and from the plurality of second estimated flow values (25) as a function of numerical values of the first estimated flow values (25) from the plurality of first estimated flow values (25) and as a function of numerical values of the second estimated flow values (25) from the plurality of second estimated flow values (25).

8. The method according to one of claims 2 to 7, the method comprising the following steps: assigning the estimated type of fuel gas (6) to a minimum air requirement (Lmin); and controlling at least one air actuator (3, 4) of the combustion device (1) as a function of the assigned minimum air requirement (Lmin).

9. The method according to one of claims 2 to 7, the method comprising the following steps: assigning the estimated type of fuel gas (6) to a calorific value (Hu); establishing a correction factor from the assigned calorific value (Hu) and a set calorific value of the combustion device (1); and correcting an air supply (5) of the combustion device (1) on the basis of at least one air actuator (3, 4) of the combustion device (1) or on the basis of the at least one air actuator (3, 4) of the combustion device (1) in proportion to the correction factor.

10. The method according to one of claims 2 to 7, the method comprising the following steps: correcting an operating characteristic curve on the basis of the estimated type of fuel gas (6), wherein the operating characteristic curve is selected from: - a first operating characteristic curve between temperature-compensated heat output and fuel gas supply (16), or - a second operating characteristic curve between temperature-compensated difference and fuel gas supply (16); determining a current fuel gas supply on the basis of the corrected operating characteristic curve and on the basis of a further variable selected from: - the temperature-compensated heat output, or - the temperature-compensated difference; and controlling at least one fuel actuator (7, 8) of the combustion device (1) as a function of the current fuel gas supply.

11. The method according to one of claims 2 to 7, the method comprising the following steps: assigning the estimated type of fuel gas (6) to a calorific value (Hu); correcting an operating characteristic curve on the basis of the assigned calorific value (Hu), wherein the operating characteristic curve is selected from: - a first operating characteristic curve between temperature-compensated heat output and fuel gas supply (16), or - a second operating characteristic curve between temperature-compensated difference and fuel gas supply (16); determining a current fuel gas supply on the basis of the corrected operating characteristic curve and on the basis of a further variable selected from: - the temperature-compensated heat output, or - the temperature-compensated difference; and controlling at least one fuel actuator (7, 8) of the combustion device (1) as a function of the current fuel gas supply.

12. The method according to one of claims 1 to 11, wherein the combustion device (1) comprises a or the closed- and / or open-loop control unit (13) with an operator control unit and wherein a plurality of mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53) for selectable fuel gases (6) and dependent on the first temperature (TM), are saved in the closed- and / or open-loop control unit (13), the method comprising the following step: on setting the combustion device (1), selecting the saved mapping rules, dependent on the first temperature (TM) and on the fuel gas composition, from the plurality of mapping rules (40, 44 / 49, 45 / 50, 46 / 51, 47 / 52, 48 / 53), with the assistance of the operator control unit.

13. Combustion device (1) comprising a combustion chamber (2), a fuel gas supply channel for the supply of a fuel gas (6) to the combustion chamber (2), a mass flow sensor (11) in or on the fuel gas supply channel and a closed- and / or open-loop control unit (13) in communicative connection with the mass flow sensor (11); wherein the mass flow sensor (11) comprises a heating element (26), a first resistor element (29) and a second resistor element (27, 28) different from the first resistor element (29) and arranged up- or downstream of the heating element (26), and / or a third resistor element (28, 27) different from the first resistor element (29) and arranged up- or downstream of the heating element (26) and / or a fourth resistor element (28, 27) different from the first (29) and second (27, 28) resistor elements and arranged up- or downstream relative to the heating element (26) opposingly relative to the second resistor element (27, 28), wherein the closed- and / or open-loop control unit (13) is configured to carry out a method according to one of claims 1 to 11.

14. Computer program product comprising commands which cause the combustion device (1) according to claim 13 to carry out the method steps according to one of claims 1 to 12.

15. Computer-readable data storage medium, on which the computer program product according to claim 14 is stored.