Method for matching a particle filter temperature adjustment

Abstract

The invention relates to a method for adjusting the temperature of a particle filter of an exhaust line ( 1 ) during a regeneration phase of said filter by injecting fuel into the exhaust gases, and which includes the steps of: measuring the temperature (T 5 ) in the particle filter; predetermining an amount of fuel to inject into the exhaust gases (Qigec), said amount including a first component (Qd c) predetermined by means of an open control loop not factoring in the measured temperature, and said amount including a second component (Qc 2 ) predetermined by means of a closed control loop factoring in the measured temperature; and, on the basis of the amplitude of the second component relative to the predetermined fuel amount, predetermining a correction term (Kc) of the first component and applying said correction term in the open control loop.

1 . A method for regulating the temperature of a particle filter in an exhaust line of an engine during a regeneration phase of the particle filter, by injecting fuel into exhaust gas flowing through the exhaust line, comprising the steps of:
 measuring the temperature at the particle filter;   determining a quantity of fuel to be injected in the exhaust gas (Qigec), the quantity including a first component (Qc 1   c ) determined through the intermediary of an open control loop not taking into account the measured temperature, and a second component (Qc 2 ) determined through the intermediary of a closed control loop taking into account the measured temperature;   calculating a correction factor (Kc) of the first component as a function of the amplitude of the second component in comparison with the calculated quantity of fuel, and applying the correction factor in the open control loop.   
     
     
         2 . The method according to  claim 1 , further comprising the steps of calculating an indicator (I) representative of the amplitude of the second component (Qc 2 ) in comparison with the quantity of injected fuel (Q igec ), and applying the correction factor of the first component in the open control loop when the indicator exceeds a predetermined threshold (S). 
     
     
         3 . The method according to  claim 2 , wherein said threshold (S) is calculated as a function of at least one operating parameter of the engine. 
     
     
         4 . The method according to  claim 2 , wherein the correction factor (Kc) of the first component is only applied in the open control loop when several successive calculated values of the indicator (I) exceed said threshold (S). 
     
     
         5 . The method according to  claim 2 , wherein the indicator I is calculated with the following equation: 
       
         
           
             
               I 
               = 
               
                 
                   
                     ∫ 
                     RG 
                     
                         
                     
                   
                    
                   
                     
                       ( 
                       
                         
                           
                             Qc 
                              
                             
                                 
                             
                              
                             2 
                           
                           
                             
                                
                               
                                 Qc 
                                  
                                 
                                     
                                 
                                  
                                 2 
                               
                                
                             
                             + 
                             
                               Q 
                               IGEC 
                             
                           
                         
                         - 
                         
                           
                             Qc 
                              
                             
                                 
                             
                              
                             
                               2 
                               ini 
                             
                           
                           
                             
                               
                                  
                                 
                                   Qc 
                                    
                                   
                                       
                                   
                                    
                                   2 
                                 
                                  
                               
                               ini 
                             
                             + 
                             
                               Q 
                               
                                 IGEC 
                                 ini 
                               
                             
                           
                         
                       
                       ) 
                     
                      
                     
                         
                     
                      
                     
                        
                       t 
                     
                   
                 
                 
                   
                     ∫ 
                     RG 
                     
                         
                     
                   
                    
                   
                      
                     t 
                   
                 
               
             
           
         
       
       where RG is the regeneration time, Qc 2   ini  and Qc 2  are the flow values of the second component calculated respectively at the a reference time and during the calculation in progress, and Qigec ini  and Qigec are the flow values of the fuel quantity to be injected in the exhaust gas calculated respectively at the reference time and during the calculation in progress. 
     
     
         6 . The method according to  claim 1 , further comprising the step of determining an exhaust gas flow and an exhaust gas temperature upstream of an oxidizing catalyst installed upstream of the particle filter, wherein the open loop control is based on a model estimating the temperature at the particle filter as a function of the exhaust gas flow, the exhaust gas temperature, and as a function of the quantity of fuel to be injected (Qigec) in the exhaust gas. 
     
     
         7 . The method according to  claim 1 , further comprising the steps of detecting an engine dysfunction and maintaining the applied correction factor when the dysfunction is detected. 
     
     
         8 . The method according to  claim 1 , wherein the closed control loop comprises an integral proportional regulator. 
     
     
         9 . An automotive vehicle equipped with an exhaust line comprising a particle filter, a fuel injection device in the exhaust line upstream of the particle filter; a measuring device for measuring the temperature (T 5 ) at the particle filter; a device for calculating the quantity of fuel to be injected in the exhaust gas in order to regulate the temperature (T 5 ) at the particle filter, including an open control loop not taking into account the measured temperature and determining a first component of said fuel quantity (Qc 1   c ), and including a closed control loop taking into account the measured temperature and determining the second component (Qc 2 ) of said fuel quantity;
 wherein the calculation device of the fuel quantity to be injected determines a correction factor (Kc) of the first component and application of this correction factor in the open control loop in function of the amplitude of the second component in comparison with the determined quantity of fuel to be injected.