Engine control to reduce emissions variability
AssigneeDeere & Company
InventorsJohn Thomas Kubesh, Daniel James Podnar, John Phillip Latusek, Donald Lee McCaw
Life of this patent
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Abstract
A system and method of controlling an engine includes sensing a concentration of NOx in exhaust gases produced by the engine and generating a sensed NOx value representative thereof, and controlling an engine control set point as a function of the sensed NOx value. The system also calculates a NOx difference value by subtracting a base NOx value from the sensed NOx value, and if an absolute value of the difference value exceeds a threshold, modifying the set point as a function of the NOx difference value. The method also includes sensing engine RPM, sensing engine manifold absolute pressure (MAP), determining the NOx value as a function of sensed engine RPM and MAP.
Claims12
A method of controlling an engine to reduce variability of engine exhaust emissions, comprising:
- sensing a concentration of oxide of nitrogen (NOx) in exhaust gases produced by the engine with a single NOx sensor which has an output which is substantially proportional to concentration of NOx in said exhaust gases, and generating a sensed NOx value representative thereof;
- generating a base NOx value;
- calculating an NOx difference value by subtracting the base NOx value from the sensed NOx value;
- and
- modifying an engine control system set point as a function of the NOx difference value in order to reduce an amount of NOx in the engine exhaust.
A system for controlling an engine to reduce variability of engine exhaust emissions, comprising:
- a single NOx concentration sensor in an exhaust of the engine generating a sensed NOx value representative thereof, NOx sensor having an output which is substantially proportional to concentration of NOx in said exhaust gases;
- and
- a control unit which generates a base NOx value, calculates a NOx difference value by subtracting the base NOx value from the sensed NOx value, and modifies an engine control system set point as a function of the NOx difference value in order to reduce variability of NOx in the engine exhaust.
Dependencies are inferred from the claim text.