Approach for engine control and diagnostics
AssigneeFord Global Technologies, LLC
InventorsPankaj Kumar, Imad Hassan Makki, Dimitar Petrov Filev
Life of this patent
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Abstract
Embodiments for an engine exhaust are provided. In one example, a method comprises adjusting a fuel injection amount based on a fractional oxidation state of a catalyst, the fractional oxidation state based on reaction rates of a plurality of exhaust gas species throughout a catalyst longitudinal axis and a set of axially-averaged mass balance and energy balance equations for a fluid phase and a washcoat of the catalyst, and further based on feedback from a downstream air-fuel ratio sensor. In this way, a simplified catalyst model may be used to control air-fuel ratio.
Claims19
An engine exhaust method, comprising:
- adjusting, via a first controller communicating with sensors and actuators, a fuel injection amount based on a fractional oxidation state of a catalyst, the fractional oxidation state based on reaction rates of a plurality of exhaust gas species throughout a catalyst longitudinal axis and a set of axially-averaged mass balance and energy balance equations for a fluid phase and a washcoat of the catalyst, and further based on separate feedback from a downstream air-fuel ratio sensor.
A method for an engine including a catalyst, comprising:
- determining, via a controller, catalyst activity based on an error between predicted exhaust gas sensor output and measured exhaust gas sensor output;
- applying, via the controller, the catalyst activity and a plurality of inlet exhaust species concentrations to a catalyst model including a set of axially-averaged mass balances and energy balances of a fluid phase and washcoat of the catalyst to determine a total oxygen storage capacity and fractional oxidation state of the catalyst;
- maintaining, via the controller, a desired air-fuel ratio based on the total oxygen storage capacity and fractional oxidation state of the catalyst, as well as based on separate feedback from a downstream air-fuel ratio sensor provided in parallel with the fractional oxidation state;
- and
- indicating, via the controller, catalyst degradation if the catalyst activity or the total oxygen storage capacity is less than a threshold;
- and
- adjusting, via the controller and an actuator, fuel injection via a first controller based on feedback from an upstream air-fuel ratio sensor.
An engine exhaust method, comprising:
- adjusting, via a controller communicating with sensors and fuel injectors, a fuel injection amount based on:
- a fractional oxidation state (FOS) of a catalyst relative to an FOS set-point, the FOS based on reaction rates of a plurality of exhaust gas species throughout a catalyst longitudinal axis and a set of axially-averaged mass balance and energy balance equations, and
- separate feedback from a downstream HEGO sensor relative to a HEGO set-point, the FOS and HEGO set-points tied together.
Dependencies are inferred from the claim text.