Emissions control in diesel engines

Abstract

An exhaust system is configured with a diesel oxidation catalyst that receives first exhaust gases from a diesel engine, a diesel particulate filter that receives second exhaust gases from the diesel oxidation catalyst. A first sensor in the exhaust system determines first exhaust gases data and transmits the first exhaust gases data to a controller while a second sensor determines second exhaust gases data and transmits the second exhaust gases data to the controller. The controller estimates unmeasured exhaust gases data based on the first exhaust gases data and the second exhaust gases data and determines when to initiate a regeneration cycle for the diesel particulate filter.

What is claimed is: 
     
         1 . A system comprising:
 a diesel oxidation catalyst that receives first exhaust gases from a diesel engine;   a diesel particulate filter that receives second exhaust gases from the diesel oxidation catalyst;   a first sensor that determines first exhaust gases data and transmits the first exhaust gases data to a controller;   a second sensor that determines second exhaust gases data and transmits the second exhaust gases data to the controller; and   the controller that estimates unmeasured exhaust gases data based on the first exhaust gases data and the second exhaust gases data and determines when to initiate a regeneration cycle for the diesel particulate filter.   
     
     
         2 . The system of  claim 1 , wherein the first sensor determines the first exhaust gases data based on sensing the first exhaust gases, and
 wherein the second sensor determines the second exhaust gases data based on sensing third exhaust gases exiting the diesel particulate filter.   
     
     
         3 . The system of  claim 1 , wherein at least one of the first exhaust gases data and the second exhaust gases data comprises nitrogen oxide data. 
     
     
         4 . The system of  claim 1 , wherein the controller initiates the regeneration cycle for the diesel particulate filter by transmitting an instruction to a fuel injection component. 
     
     
         5 . The system of  claim 1 , wherein the controller initiates the regeneration cycle for the diesel particulate filter by transmitting an instruction to an engine control unit. 
     
     
         6 . The system of  claim 1 , wherein the controller initiates the regeneration cycle for the diesel particulate filter by transmitting an instruction to perform at least one of:
 injecting fuel upstream from the diesel oxidation catalyst, or   a secondary post injection of fuel in a cylinder of the diesel engine.   
     
     
         7 . The system of  claim 1 , wherein the controller initiates the regeneration cycle for the diesel particulate filter by transmitting an instruction to perform at least one of:
 injecting a catalyst upstream from the diesel oxidation catalyst, or   a secondary post injection of fuel in a cylinder of the diesel engine.   
     
     
         8 . A method comprising:
 receiving first exhaust gases from a diesel engine at a diesel oxidation catalyst;   receiving second exhaust gases from the diesel oxidation catalyst at a diesel particulate filter;   determining first exhaust gases data at a first sensor;   transmitting the first exhaust gases data from the first sensor to a controller;   determining second exhaust gases data at a second sensor;   transmitting the second exhaust gases data from the second sensor to the controller; and   estimating, at the controller, unmeasured exhaust gases data based on the first exhaust gases data and the second exhaust gases data; and   determining, at the controller based on the unmeasured exhaust gases data, when to initiate a regeneration cycle for the diesel particulate filter.   
     
     
         9 . The method of  claim 8 , wherein determining the first exhaust gases data at the first sensor comprises determining the first exhaust gases data at the first sensor based on the first exhaust gases, and
 wherein determining the second exhaust gases data at the second sensor comprises determining the second exhaust gases data at the second sensor based on sensing third exhaust gases exiting the diesel particulate filter.   
     
     
         10 . The method of  claim 8 , wherein at least one of the first exhaust gases data and the second exhaust gases data comprises nitrogen oxide data. 
     
     
         11 . The method of  claim 8 , wherein determining when to initiate the regeneration cycle for the diesel particulate filter comprises transmitting an instruction to a fuel injection component. 
     
     
         12 . The method of  claim 8 , wherein determining when to initiate the regeneration cycle for the diesel particulate filter comprises transmitting an instruction to an engine control unit. 
     
     
         13 . The method of  claim 8 , further comprising initiating the regeneration cycle for the diesel particulate filter by transmitting an instruction to perform at least one of:
 injecting fuel upstream from the diesel oxidation catalyst, or   a secondary post injection of fuel in a cylinder of the diesel engine.   
     
     
         14 . The method of  claim 8 , further comprising initiating the regeneration cycle for the diesel particulate filter by transmitting an instruction to perform at least one of:
 injecting a catalyst upstream from the diesel oxidation catalyst, or   a secondary post injection of fuel in a cylinder of the diesel engine.   
     
     
         15 . An engine comprising:
 a diesel internal combustion component that generates first exhaust gases;   a diesel oxidation catalyst that receives the first exhaust gases from the diesel internal combustion component;   a diesel particulate filter that receives second exhaust gases from the diesel oxidation catalyst;   a first sensor that determines first exhaust gases data and transmits the first exhaust gases data to a controller;   a second sensor that determines second exhaust gases data and transmits the second exhaust gases data to the controller; and   the controller that estimates unmeasured exhaust gases data based on the first exhaust gases data and the second exhaust gases data and determines when to initiate a regeneration cycle for the diesel particulate filter.   
     
     
         16 . The engine of  claim 15 , wherein the first sensor determines the first exhaust gases data based on sensing the first exhaust gases, and
 wherein the second sensor determines the second exhaust gases data based on sensing third exhaust gases exiting the diesel particulate filter.   
     
     
         17 . The engine of  claim 15 , wherein at least one of the first exhaust gases data and the second exhaust gases data comprises nitrogen oxide data. 
     
     
         18 . The engine of  claim 15 , wherein the controller initiates the regeneration cycle for the diesel particulate filter by transmitting an instruction to a fuel injection component. 
     
     
         19 . The engine of  claim 15 , wherein the controller initiates the regeneration cycle for the diesel particulate filter by transmitting an instruction to an engine control unit. 
     
     
         20 . The engine of  claim 15 , wherein the controller initiates the regeneration cycle for the diesel particulate filter by transmitting an instruction to perform at least one of:
 injecting fuel upstream from the diesel oxidation catalyst, or   a secondary post injection of fuel in a cylinder of the diesel engine.