Optimized Closed-Loop Control Of A Combustion Apparatus

Abstract

Various embodiments of the teachings herein include a method for control of a combustion apparatus. An example includes loading a first characteristic curve from a memory; determining a current value of a performance variable; determining a first input value of the variable for an open-loop control mode; assigning the first input value to a first speed and/or to a first position using the first characteristic curve; determining a first open-loop control signal as a function of the first speed and/or the first position; and sending the first open-loop control signal to the first actuator, wherein the first open-loop control signal causes the first actuator to change a combustion variable including the air supply and/or the fuel supply.

1 . A method for control of a combustion apparatus comprising a combustion chamber, an air supply duct leading to the combustion chamber, a fuel supply duct leading to the combustion chamber, a first actuator selected from: an air actuator for an air supply through the air supply duct, and a fuel actuator for a fuel supply through the fuel supply duct, a waste gas path, an oxygen-based sensor in the waste gas path, and a control facility with a memory storing a first characteristic curve for the first actuator with a first speed characteristic and/or a first position characteristic with respect to a performance-based variable, and a change, the method comprising:
 loading the first characteristic curve and the change from the memory;   determining a first, current value of the performance-based variable;   determining a first input value of the performance-based variable for an open-loop control mode as a function of the first, current value of the performance-based variable and the change, wherein the determination occurs independently of an signal of the oxygen-based sensor;   assigning the first input value of the performance-based variable to a first speed and/or to a first position using the first characteristic curve;   determining a first open-loop control signal as a function of the first speed and/or the first position; and   sending the first open-loop control signal to the first actuator, wherein the first open-loop control signal causes the first actuator to change a combustion variable including the air supply and/or the fuel supply.   
     
     
         2 . The method as claimed in  claim 1 , further comprising:
 starting combustion in the combustion apparatus; and   sending the first open-loop control signal to the first actuator within five seconds of the start of combustion.   
     
     
         3 . The method as claimed in  claim 1 , wherein the change is different from zero and is constant;
 the method further comprising determining the first input value of the performance-based variable for the open-loop control mode as a function of the first, current value of the performance-based variable and the first, constant change,   wherein the determination occurs independently of the signal of the oxygen-based sensor.   
     
     
         4 . The method as claimed in  claim 1 , wherein the memory stores a change characteristic curve indicating a change characteristic with respect to the performance-based variable;
 the method further comprises:   loading the change characteristic curve from the memory;   determining the change from the first, current value of the performance-based variable by assigning the first, current value of the performance-based variable using the change characteristic curve; and   determining the first input value of the performance-based variable for the open-loop control mode as a function of the first, current value of the performance-based variable and the change from the first, current value of the performance-based variable;   wherein the determination occurs independently of the signal of the oxygen-based sensor.   
     
     
         5 . The method as claimed in  claim 1 , the method further comprising determining the first input value of the performance-based variable for the open-loop control mode as the sole function of the first, current value of the performance-based variable and the change. 
     
     
         6 . The method as claimed in  claim 3 , the method further comprising determining the first input value of the performance-based variable for the open-loop control mode as the sum of the first, current value of the performance-based variable and the change;
 wherein the determination occurs independently of the signal of the oxygen-based sensor.   
     
     
         7 . The method as claimed in  claim 1 , wherein the memory stores at least one desired value characteristic curve indicating a characteristic of a residual oxygen content and/or an oxygen concentration and/or an oxygen partial pressure with respect to the performance-based variable;
 the method further comprising:   after the first open-loop control signal has been sent, recording a signal indicating the residual oxygen content and/or the oxygen concentration and/or the oxygen partial pressure, using the oxygen-based sensor;   sending the oxygen-based signal to the control facility;   determining a measured value using the control facility on the basis of the oxygen-based signal;   determining a second, current value of the performance-based variable;   loading the desired value characteristic curve from the memory;   assigning the second, current value of the performance-based variable to a desired value using the desired value characteristic curve;   comparing the measured value with the desired value;   generating a closed-loop control signal on the basis of the comparison between the measured value and the desired value; and   sending the closed-loop control signal to the first actuator, wherein the closed-loop control signal causes the first actuator to change the combustion variable.   
     
     
         8 . The method as claimed in  claim 7 , wherein the combustion apparatus comprises a second actuator selected from the fuel actuator and the air actuator different from the first actuator, wherein the memory stores a second characteristic curve for the second actuator indicating a second speed characteristic and/or a second position characteristic with respect to the performance-based variable;
 the method further comprising:   assigning the second, current value of the performance-based variable to a second speed and/or to a second position using the second characteristic curve, wherein the assignment takes place independently of the change;   determining a second open-loop control signal as a function of the second speed and/or the second position; and   sending the second open-loop control signal to the second actuator, wherein the second open-loop control signal causes the second actuator to change the combustion variable.   
     
     
         9 . The method as claimed in  claim 7 , the method comprising determining a second, current value of the performance-based variable from the first, current value of the performance-based variable. 
     
     
         10 . The method as claimed in  claim 7 , the method comprising determining a second, current value of the performance-based variable after the first open-loop control signal has been sent. 
     
     
         11 . The method as claimed in  claim 7 , the method further comprising:
 checking the measured value for an error;   if checking of the measured value yields the error:   determining a third, current value of the performance-based variable;   determining a further input value of the performance-based variable for the open-loop control mode as a function of the second or third current value of the performance-based variable and the change, wherein the determination occurs independently of the signal of the oxygen-based sensor;   assigning the further input value of the performance-based variable to a third speed and/or to a third position using the first characteristic curve;   determining an emergency open-loop control signal as a function of the third speed and/or the third position; and   sending the emergency open-loop control signal to the first actuator, wherein the emergency open-loop control signal causes the first actuator to change the combustion variable.   
     
     
         12 . The method as claimed in  claim 11 , wherein the memory stores a limit value for the measured value;
 the method further comprising:   checking the measured value for the error by comparing the measured value with the limit value; and   identifying the error if the measured value is smaller than the limit value.   
     
     
         13 . A combustion apparatus comprising:
 a combustion chamber;   an air supply duct leading to the combustion chamber;   a fuel supply duct leading to the combustion chamber;   a first actuator selected from an air actuator for an air supply through the air supply duct and a fuel actuator for a fuel supply through the fuel supply duct;   a second actuator selected from the fuel actuator and the air actuator different from the first actuator;   a waste gas path;   an oxygen-based sensor in the waste gas path; and   a control facility with a memory storing a first characteristic curve indicating for the first actuator a first speed characteristic and/or a first position characteristic with respect to a performance-based variable, and a second characteristic curve indicating for the second actuator a second speed characteristic and/or a second position characteristic with respect to the performance-based variable, a change, and a limit value for a measured value;   wherein the control facility communicates with the first actuator, the second actuator, the oxygen-based sensor, and the memory and is configured to:   load the first characteristic curve and the change from the memory;   determine a first, current value of the performance-based variable;   determine a first input value of the performance-based variable for an open-loop control mode as a function of the first, current value of the performance-based variable and the change, wherein the determination occurs independently of an signal of the oxygen-based sensor;   assign the first input value of the performance-based variable to a first speed and/or to a first position using the first characteristic curve;   determine a first open-loop control signal as a function of the first speed and/or the first position; and   send the first open-loop control signal to the first actuator, wherein the first open-loop control signal causes the first actuator to change a combustion variable including the air supply and/or the fuel supply.