Method for Operating a Particle Trap and Device for Carrying Out the Method

Abstract

A method for operating a particle trap, in particular an open particle trap, in an exhaust gas system of an internal combustion engine, includes determining a first point in time in which the particle trap falls below a first effectiveness limiting value, increasing the effectiveness of the particle trap by adjusting at least one specific operating parameter of the internal combustion engine, while exhaust gas produced by the internal combustion engine does not exceed a temperature of 500° C. in the vicinity of the particle trap, determining a second point in time in which the particle trap exceeds a second effectiveness limiting value, and activating normal operation of the internal combustion engine. The method and an associated device ensure operation of an exhaust gas system of an internal combustion engine, with conservation of fuel, savings of materials and simultaneous high effectiveness of the particle trap integrated into the exhaust gas system.

1 . A method for operating a particle trap in an exhaust gas system of an internal combustion engine, the method comprising the following steps:
 a) determining a first point in time in which the particle trap falls below a first effectiveness limiting value;   b) increasing an effectiveness of the particle trap by adjusting at least one specific operating parameter of the internal combustion engine, while exhaust gas produced by the internal combustion engine has a sufficiently low temperature in vicinity of the particle trap to ensure that substantially no thermal regeneration of particles occurs;   c) determining a second point in time in which the particle trap exceeds a second effectiveness limiting value; and   d) activating normal operation of the internal combustion engine.   
   
   
       2 . The method according to  claim 1 , wherein the particle trap is an open particle trap. 
   
   
       3 . The method according to  claim 1 , wherein step a) includes determining an instantaneous particle loading state of the particle trap with particles. 
   
   
       4 . The method according to  claim 2 , which further comprises calculating the instantaneous loading state. 
   
   
       5 . The method according to  claim 2 , which further comprises determining the instantaneous loading state based on a pressure differential in the exhaust gas system between a first position upstream of the particle trap and a second position downstream of the particle trap. 
   
   
       6 . The method according to  claim 1 , which further comprises, during step b), increasing the effectiveness of the particle trap with respect to particles contained in the exhaust gas by at least 20% compared to normal operation of the internal combustion engine. 
   
   
       7 . The method according to  claim 1 , which further comprises determining a duration of step b) as a function of an underlying loading state. 
   
   
       8 . The method according to  claim 1 , which further comprises determining a duration of step b) as a function of a temperature of the exhaust gas during the effectiveness increase. 
   
   
       9 . The method according to  claim 1 , which further comprises determining a duration of step b) as a function of a nitrogen dioxide concentration in the exhaust gas during the effectiveness increase. 
   
   
       10 . The method according to  claim 1 , which further comprises determining a duration of step b) as a function of a concentration of water in the exhaust gas during the efficiency increase. 
   
   
       11 . The method according to  claim 1 , which further comprises determining a duration of step b) as a function of a concentration of ozone in the exhaust gas during the effectiveness increase. 
   
   
       12 . The method according to  claim 1 , which further comprises adjusting the at least one specific operating parameter of the internal combustion engine during step b) to increase a nitrogen dioxide concentration in the exhaust gas being produced. 
   
   
       13 . The method according to  claim 1 , which further comprises adjusting the at least one specific operating parameter of the internal combustion engine during step b) to increase an oxygen concentration in the exhaust gas being produced. 
   
   
       14 . The method according to  claim 1 , which further comprises adjusting the at least one specific operating parameter of the internal combustion engine during step b) to increase a temperature of the exhaust gas being produced by a maximum of 50° C. in vicinity of the particle trap. 
   
   
       15 . A device for operating a particle trap, the device comprising:
 a vehicle having an internal combustion engine and an exhaust gas system;   an engine control operating said internal combustion engine;   at least one particle trap disposed in said exhaust gas system; and   a device for determining an effectiveness of said at least one particle trap according to  claim 1 .   
   
   
       16 . The device according to  claim 15 , wherein said particle trap is open. 
   
   
       17 . The device according to  claim 15 , wherein said exhaust gas system includes an exhaust gas recirculation device. 
   
   
       18 . A vehicle, comprising:
 an internal combustion engine;   an engine control operating said internal combustion engine;   an exhaust gas system connected to said internal combustion engine;   at least one particle trap disposed in said exhaust gas system; and   a device for determining an effectiveness of said at least one particle trap according to  claim 1 .   
   
   
       19 . The vehicle according to  claim 18 , wherein said particle trap is open. 
   
   
       20 . The vehicle according to  claim 18 , wherein said exhaust gas system includes an exhaust gas recirculation device.