Method and system for regenerating exhaust system filtering and catalyst components using variable high engine idle

Abstract

A method and system for regenerating particulate filters, catalyzed soot filters, and NOx adsorber catalysts for a vehicle having a compression ignition engine.

1 . A method of regenerating particulate filters, catalyzed soot filters, Selective Catalytic Reduction systems and NOx adsorber catalysts for a vehicle equipped with a compression ignition engine having an engine central module (ECM) and an integrated starter/alternator/flywheel/retarder assembly, comprising:
 sensing the condition of the particulate filters, catalyzed soot filters, and NOx adsorber catalysts and generating an initiate cleaning cycle signal upon sensing that the filters and catalysts require cleaning;   monitoring operation of the engine and the vehicle to determine whether the engine is idling and whether the vehicle is stopped and generating an engine idling/vehicle stopped signal;   receiving the initiate cleaning cycle signal and the engine idling/vehicle stopped signal;   sensing the temperature of an exhaust gas stream and generating a low temperature signal upon sensing that the exhaust gas temperature is insufficient for regeneration of the filters;   sensing the ambient air temperature of incoming air into a turbo compressor on the engine.   initiating engine control parameter adjustments based upon ambient air temperature and/or exhaust gas temperature to increase or decrease engine speed and exhaust gas temperature to regenerate the filters;   resuming normal engine idle operating parameters when filters are regenerated.   
   
   
       2 . The method of  claim 1 , wherein sensing the condition of the filter is accompanied by sensing back pressure in the exhaust system. 
   
   
       3 . The method of  claim 2 , wherein the cleaning cycle is initiated when the exhaust back pressure exceeds a pre-determined level, and ceases when the exhaust system back pressure is below a second pre-determined level. 
   
   
       4 . The method of  claim 1 , wherein the cleaning cycle is initiated when a the ECM, based upon a modeled approximation of soot initiates the particulate filter regeneration cycle, and the particulate filter regeneration cycle ceases based upon the modeled approximation of soot. 
   
   
       5 . The method of  claim 1 , further comprising a NOx adsorber catalyst by adjusting the air/fuel ratio. 
   
   
       6 . The method of  claim 1 , wherein the engine operating parameters adjusted by the engine central module are fueling and timing parameters. 
   
   
       7 . The method of  claim 1 , further comprising actuating a warning light in response to the engine control module receiving the signal to initiate a regeneration cycle. 
   
   
       8 . The method of  claim 7 , wherein upon activating the warning light, the engine central module initiates steps such as engine derate or possible engine shut down unless an operator initiates the regeneration cycle. 
   
   
       9 . The method of  claim 8 , further comprising actuating a manual switch by the operator upon activation of the warning light. 
   
   
       10 . A system for regenerating particulate filters, catalyzed soot filters, Selective Catalytic Reduction systems, and NOx absorber catalysts for a compression ignition engine of a vehicle, comprising:
 a starter;   an alternator;   a flywheel;   a retarder, wherein the starter, alternator, flywheel and retarder are combined as an integrated assembly;
 a load bank heater disposed in an exhaust pipe; and 
 an engine control module adapted to receive a signal to initiate a regeneration cycle, wherein the engine control module senses exhaust gas temperature and turbo compressor inlet ambient air temperature adjusts engine operating parameters after receiving the initiate regeneration cycle signal when the vehicle is at rest and the engine is idling, wherein the signal to initiate the regeneration cycle includes a desulfation cycle of a NOx absorber catalyst that is initiated in response to signals received from at least one exhaust NOx sensor, at least one exhaust gas temperature sensor, and at least one air/fuel ratio sensor by the engine control module. 
   
   
   
       11 . The system of  claim 10  wherein the exhaust gas temperature sensor generates a low temperature signal indicating that the exhaust temperature is below a predetermined level that is sufficient for regeneration, wherein the load bank heater is activated that raises the temperature of the exhaust in conjunction with increasing the load on the engine applied by the integrated assembly, wherein the engine control module brings the engine to a specified operating speed. 
   
   
       12 . The system of  claim 10  wherein the signal to initiate a regeneration cycle for a filter is generated by a sensor in the exhaust that monitors exhaust back pressure. 
   
   
       13 . The system of  claim 10 , wherein the cleaning cycle is initiated when a the ECM, based upon a modeled approximation of soot initiates the particulate filter regeneration cycle, and the particulate filter regeneration cycle ceases based upon the modeled approximation of soot. 
   
   
       14 . The system of  claim 10  wherein during the desulfation cycle of a NOx absorber catalyst the engine operating parameter adjusted is the air/fuel ratio. 
   
   
       15 . The system of  claim 10  wherein the engine operating parameters adjusted by the engine control module are fueling and timing parameters. 
   
   
       16 . The system of  claim 10  wherein a warning light is activated in response to the engine control module receiving the signal to initiate a user requested regeneration cycle. 
   
   
       17 . The system of  claim 16  wherein upon activating the warning light, the engine control module disables the engine unless an operator initiates the regeneration cycle. 
   
   
       18 . The system of  claim 16  wherein the operator activates the regeneration cycle by actuating a manual switch upon activation of the warning light. 
   
   
       19 . A method of regenerating particulate filters, catalyzed soot filters, Selective Catalytic Reduction systems and NOx adsorber catalysts for a vehicle equipped with a compression ignition engine having an engine central module (ECM) and an integrated starter/alternator/flywheel/retarder assembly, comprising:
 a) determining whether the engine is idling;   b) determining whether an engine user is requesting regeneration;   c) determining whether it is acceptable to initiate regeneration;   d) determining ambient temperature of air to inlet of turbo air compressor;   e) elevating engine rpm to a desired engine rpm based upon ambient temperature and initiate regeneration and desulfation;   f) determining whether the exhaust gas temperature is sufficient to regenerate the particulate filter; and   g) varying the engine speed using ambient air temperature until the exhaust gas temperature is sufficient to regenerate the particulate filter   
   
   
       20 . The method off  claim 19 , wherein if it is determined not to be acceptable to initiate regeneration, engine idle is continued, and where if the exhaust temperature is determined to be sufficient to regenerate particulate filter, engine speed is continued at a desired rpm.