Method of regulating an internal combustion engine

Abstract

Method of regulating an internal combustion engine in order to reach presettable nitrogen oxide emission values of the internal combustion engine, wherein the internal combustion engine is supplied at least some of the time with a first fuel and at least some of the time with a second fuel, the quantity of the first fuel supplied to the internal combustion engine per unit of time being controlled according to a preset control actual value or kept constant and the quantity of the second fuel supplied to the internal combustion engine per unit of time to reach a presettable nitrogen oxide emission value being regulated according to at least one recorded engine parameter.

1. A method of regulating an internal combustion engine in order to reach presettable nitrogen oxide emission values of the internal combustion engine, comprising:
 supplying the internal combustion engine at least a portion of an operating time with a first fuel and at least a portion of the operating time with a second fuel;  
 controlling a quantity of the first fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulating a quantity of the second fuel supplied to the internal combustion engine per unit of time by matching a mixture pressure influenced by the quantity of the second fuel in an intake of the internal combustion engine to a mixture pressure target value determined according to a delivered output and a preset nitrogen oxide emission value of the internal combustion engine so as to reach the preset nitrogen oxide emission value.  
 
     
     
       2. The method of  claim 1 , wherein the first fuel is a first combustible gas, and the second fuel is a second combustible gas. 
     
     
       3. The method of  claim 1 , wherein the mixture pressure target value determined according to the delivered output and the preset nitrogen oxide emission value is further determined according to corresponding target values intended for an operation of the internal combustion engine with the first fuel and for an operation of the internal combustion engine with the second fuel and further according to a standardization factor x. 
     
     
       4. The method of  claim 3 , wherein the standardization factor x is determined according to the calorific value or the CH 4  content of the first fuel or of the second fuel or of a fuel mixture. 
     
     
       5. The method of  claim 3 , wherein the mixture pressure target value is further determined by taking into account fluctuations in the composition of the first fuel or of the second fuel via previously determined characteristics fields or by correction values and corresponding measured values. 
     
     
       6. A method of regulating an internal combustion engine in order to reach presettable nitrogen oxide emission values of the internal combustion engine, comprising:
 supplying the internal combustion engine at least a portion of an operating time with a first fuel and at least a portion of the operating time with a second fuel;  
 controlling a quantity of the first fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulating the quantity of the second fuel supplied to the internal combustion engine per unit of time by matching a λ-value influenced by the quantity of the second fuel in an exhaust of the internal combustion engine to a λ-target value determined according to a delivered output and a preset nitrogen oxide emission value of the internal combustion engine so as to reach the preset nitrogen oxide emission value.  
 
     
     
       7. The method of  claim 6 , wherein the first fuel is a first combustible gas, and the second fuel is a second combustible gas. 
     
     
       8. The method of  claim 6 , wherein the λ-target value determined according to the delivered output and the preset nitrogen oxide emission value is further determined according to corresponding target values intended for an operation of the internal combustion engine with the first fuel and for an operation of the internal combustion engine with the second fuel and further according to a standardization factor x. 
     
     
       9. The method of  claim 8 , wherein the standardization factor x is determined according to the calorific value or the CH 4  content of the first fuel or of the second fuel or of a fuel mixture. 
     
     
       10. The method of  claim 8 , wherein the λ-target value is further determined by taking into account fluctuations in the composition of the first fuel or of the second fuel via previously determined characteristics fields or by correction values and corresponding measured values. 
     
     
       11. A method of regulating an internal combustion engine in order to reach presettable nitrogen oxide emission values of the internal combustion engine, comprising:
 supplying the internal combustion engine at least a portion of an operating time with a first fuel and at least a portion of the operating time with a second fuel;  
 performing a first operating mode at a first side of a preset operation-switching point, the first operating mode including: 
 controlling a quantity of the first fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulating the quantity of the second fuel supplied to the internal combustion engine per unit of time according to at least one recorded engine parameter so as to reach the preset nitrogen oxide emission value;  
 
 performing a second operating mode at a second side of the preset operation-switching point, the second operating mode including: 
 controlling a quantity of the second fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulating the quantity of the first fuel supplied to the internal combustion engine per unit of time according to at least one recorded engine parameter so as to reach the preset nitrogen oxide emission value; and  
 
 switching an operating mode of the internal combustion engine between the first operating mode and the second operating mode.  
 
     
     
       12. The method of  claim 11 , wherein the first fuel is a first combustible gas, and the second fuel is a second combustible. 
     
     
       13. The method of  claim 11 , wherein said switching comprises switching an operating mode of the internal combustion engine so as to change a mixing ratio between the first fuel and the second fuel whereby both the first fuel and the second fuel are supplied to the internal combustion engine. 
     
     
       14. The method of  claim 11 , wherein said switching comprises switching an operating mode of the internal combustion engine such that an operation using one of the first fuel and the second fuel is replaced by an operation using the other of the first fuel and the second fuel. 
     
     
       15. The method of  claim 11 , wherein the preset operation-switching point is defined by a preset ratio between the quantity of the first fuel supplied per unit of time and the quantity of the second fuel supplied per unit of time. 
     
     
       16. The method of  claim 15 , wherein the preset ratio of the operation-switching point is between 1:4 and 4:1. 
     
     
       17. The method of  claim 15 , wherein the preset ratio of the operation-switching point is between 1:2 and 2:1. 
     
     
       18. A regulation section for use with an internal combustion engine, said regulation section comprising:
 a fuel mixing device; and  
 a regulator operable to control said fuel mixing device to: 
 supply the internal combustion engine at least a portion of an operating time with a first fuel and at least a portion of the operating time with a second fuel;  
 control a quantity of the first fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulate a quantity of the second fuel supplied to the internal combustion engine per unit of time by matching a mixture pressure influenced by the quantity of the second fuel in an intake of the internal combustion engine to a mixture pressure target value determined according to a delivered output and a preset nitrogen oxide emission value of the internal combustion engine so as to reach the preset nitrogen oxide emission value.  
 
 
     
     
       19. The regulation section of  claim 18 , wherein said fuel mixing device includes:
 a first volume flow dosage valve for supplying the first fuel to the internal combustion engine; and  
 a second volume flow dosage valve for supplying the second fuel to the internal combustion engine.  
 
     
     
       20. The regulation section of  claim 18 , wherein said fuel mixing device includes:
 a volume flow dosage valve for supplying the first fuel to the internal combustion engine; and  
 a volume flow-controllable gas mixer for receiving the second fuel and supplying the second fuel to the internal combustion engine.  
 
     
     
       21. A regulation section for use with an internal combustion engine, said regulation section comprising:
 a fuel mixing device; and  
 a regulator operable to control said fuel mixing device to: 
 supply the internal combustion engine at least a portion of an operating time with a first fuel and at least a portion of the operating time with a second fuel;  
 control a quantity of the first fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulate the quantity of the second fuel supplied to the internal combustion engine per unit of time by matching a λ-value influenced by the quantity of the second fuel in an exhaust of the internal combustion engine to a λ-target value determined according to a delivered output and a preset nitrogen oxide emission value of the internal combustion engine so as to reach the preset nitrogen oxide emission value.  
 
 
     
     
       22. The regulation section of  claim 21 , wherein said fuel mixing device includes:
 a first volume flow dosage valve for supplying the first fuel to the internal combustion engine; and  
 a second volume flow dosage valve for supplying the second fuel to the internal combustion engine.  
 
     
     
       23. The regulation section of  claim 21 , wherein said fuel mixing device includes:
 a volume flow dosage valve for supplying the first fuel to the internal combustion engine; and  
 a volume flow-controllable gas mixer for receiving the second fuel and supplying the second fuel to the internal combustion engine.  
 
     
     
       24. A regulation section for use with an internal combustion engine, said regulation section comprising:
 a fuel mixing device; and  
 a regulator operable to control said fuel mixing device to: 
 supply the internal combustion engine at least a portion of an operating time with a first fuel and at least a portion of the operating time with a second fuel;  
 perform a first operating mode at a first side of a preset operation-switching point, the first operating mode including: 
 controlling a quantity of the first fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulating the quantity of the second fuel supplied to the internal combustion engine per unit of time according to at least one recorded engine parameter so as to reach the preset nitrogen oxide emission value;  
 
 perform a second operating mode at a second side of the preset operation-switching point, the second operating mode including: 
 controlling a quantity of the second fuel supplied to the internal combustion engine per unit of time according to one of a preset control target value or a constant value; and  
 regulating the quantity of the first fuel supplied to the internal combustion engine per unit of time according to at least one recorded engine parameter so as to reach the preset nitrogen oxide emission value; and  
 
 switch an operating mode of the internal combustion engine between the first operating mode and the second operating mode.  
 
 
     
     
       25. The regulation section of  claim 24 , wherein said fuel mixing device includes:
 a first volume flow dosage valve for supplying the first fuel to the internal combustion engine; and  
 a second volume flow dosage valve for supplying the second fuel to the internal combustion engine.  
 
     
     
       26. The regulation section of  claim 24 , wherein said fuel mixing device includes:
 a volume flow dosage valve for supplying the first fuel to the internal combustion engine; and  
 a volume flow-controllable gas mixer for receiving the second fuel and supplying the second fuel to the internal combustion engine.