Method and device for regenerating the particle filter of an internal combustion engine during the transient operating phases thereof

Abstract

The invention relates to a method for regenerating a particle filter on the exhaust line of an internal combustion engine, in which fuel is injected into the exhaust tube upstream of an oxidation catalyst which is disposed upstream of the particle filter. The invention is characterised in that during regeneration: the injection of fuel into the exhaust tube is interrupted when the operation of the engine enters a critical zone (S 2 ) defined by maximum load and speed limit values; the injection of fuel is re-established when the operation of the engine returns to the non-critical zone (S 1 ); and, during the transient operating phases between the two zones (S 1 , S 2 ), the volume flow rate of the exhaust gases is measured and, as a function of said measurement, the fuel injection rate is reduced or the fuel injection is deferred.

1 - 8 . (canceled) 
   
   
       9 . A method for regenerating a particle filter positioned in an exhaust line of an internal combustion engine, the method comprising:
 while the particle filter is being regenerated, injecting fuel into the exhaust line upstream of an oxidation catalytic converter positioned upstream of the particle filter, and comprising during regeneration:
 interrupting injection of fuel into the exhaust line when the engine operation enters a critical zone defined by speed and load upper limits, 
 resuming injection of fuel when engine operation returns to a non-critical zone, 
 during transient phases of operation between the critical and non-critical, measuring zones, measuring the volume flow rate of exhaust gases and reducing the fuel injection flow rate or deferring the injection of fuel on the basis of the measurement. 
   
   
   
       10 . A method according to  claim 9 , wherein fuel injection is resumed once the volume flow rate of exhaust gases has dropped back below a predetermined threshold. 
   
   
       11 . A method according to  claim 9 , wherein a correction is applied to the maximum flow rate at which fuel is injected, on the basis of the volume flow rate of exhaust gases. 
   
   
       12 . A device for implementing the method according to  claim 9 , comprising:
 means for interrupting the injection of fuel into the exhaust line when operation of the engine enters the critical zone;   means for resuming fuel injection when engine operation has returned to the non-critical zone;   means for measuring or estimating the volume flow rate of exhaust gases during the transient phases of operation; and   means for controlling the injection of fuel when the volume flow rate of exhaust gases has dropped back below a predetermined threshold, or means for correcting the maximum flow rate at which fuel is injected on the basis of the volume flow rate of the exhaust gases.   
   
   
       13 . A device according to  claim 12 , further comprising a flow meter positioned on the exhaust tube or equipment that estimates the volume flow rate of the exhaust gases. 
   
   
       14 . A device according to  claim 12 , wherein the means for measuring the volume flow rate of the exhaust gases interfaces with a hysteresis module for controlling the injection of fuel. 
   
   
       15 . A device according to  claim 14 , wherein two thresholds of the hysteresis module are set based on engine speed and load. 
   
   
       16 . A device according to  claim 12 , wherein the means for correcting the maximum injection flow rate includes a map that interfaces with the means for measuring the volume flow rate of the exhaust gases.