Emission control system
AssigneeDENSO International America, Inc.
InventorEdward Szczepanski
Life of this patent
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Abstract
An exhaust system includes a catalytic converter, a particulate filter, a first sensor, and a second sensor. The particulate filter is disposed downstream of the catalytic converter. The first sensor is disposed upstream of the catalytic converter and provides an output identifying a quantity of oxygen in an exhaust flow. The second sensor is disposed downstream of the catalytic converter and upstream of the particulate filter and provides an output identifying a quantity of oxygen in the exhaust flow exiting the catalytic converter.
Claims18
An exhaust system comprising:
- a catalytic converter;
- a particulate filter disposed adjacent to and downstream of said catalytic converter;
- a first sensor disposed upstream of said catalytic converter, said first sensor providing an output identifying a quantity of oxygen in an exhaust flow;
- a second sensor disposed downstream of said catalytic converter and upstream of said particulate filter, said second sensor separating said particulate filter from said adjacent catalytic converter and said second sensor providing an output identifying a quantity of oxygen in said exhaust flow exiting said catalytic converter and entering said particulate filter;
- and
- a controller configured to model a remaining storage capacity for oxygen in said catalytic converter and a remaining storage capacity for oxygen in said particulate filter from an intake air volume, an air-fuel ratio, and a stoichiometric air-fuel ratio, said intake air volume and said stoichiometric air-fuel ratio being predetermined values stored in said controller, and said first sensor being configured to measure said air-fuel ratio of said exhaust flow upstream of said catalytic converter.
A method of controlling an exhaust system comprising:
- catalyzing, with a catalytic converter, hydrocarbons and nitrous oxide from an exhaust flow from an engine;
- filtering, with a particulate filter disposed adjacent to and downstream of said catalytic converter, particulate matter from said exhaust flow;
- detecting, with a first sensor disposed upstream of said catalytic converter, a quantity of oxygen in said exhaust flow;
- detecting, with a second sensor disposed downstream of said catalytic converter and upstream of said particulate filter, a quantity of oxygen in said exhaust flow exiting said catalytic converter and entering said particulate filter, said second sensor separating said particulate filter from said adjacent catalytic converter;
- and
- modeling, with a controller, a remaining storage capacity for oxygen in said catalytic converter and a remaining storage capacity for oxygen in said particulate filter from an intake air volume, and air-fuel ratio, and a stoichiometric air-fuel ratio, said intake air volume and said stoichiometric air-fuel ratio being predetermined values stored in said controller, and said first sensor being configured to measure said air-fuel ratio of said exhaust flow upstream of said catalytic converter.
Dependencies are inferred from the claim text.