Ford Motor Company Limited

Ford Global Technolgoies, LLC

Other

Douglas R Hamburg

Eleftherios M Logothetis

Jeffrey A Cook

Dennis C Reed

Daniel Lawrence Meyer

Nicholas G Zorka

Jacobus Hendrik Visser

Richard E Soltis

Ahmed Abdelaziz Omara

John Edward Bradley

Dante S Giardini

Thomas Raymond Culbertson

Judith M Curran

Martin F Davenport

Allan Joseph Kotwicki

Daniel V Orzel

Margherita Zanini-Fisher

Philip W Husak

Lajos Rimai

Steven Ray Whittier

William Earl Leisenring

Thomas Scott Gee

Paul F Smith

David F Moyer

Thomas A Schubert

Kelvin Lee Dobbins

Wayne J Johnson

Robert G Delosh

James E Auiler

James E Hyland

Gerald P Lawson

Gottfried Hogh

Louis J Sherry

Mohammed Yussouff

Alan D Brailsford

Jerome F Hough

Active adaptive bias for closed loop air/fuel control system

A three-way catalyst model ( ) and a method for modeling the dynamic response of a three-way catalyst that divides the catalyst response into sub-regions ( ) . A sub-model ( ) is constructed that represents each sub-region ( ) . Each sub-model ( ) is assigned unique attributes at which the sub-model is activated. The attributes are based on the system parameters and states. The states may be either continuous or discrete and define a hybrid state space. A larger or smaller number of sub-regions ( ) can be utilized based on the model's ( ) use and the accuracy desired for the model ( ).

Three-way catalyst model for an engine air-to-fuel ratio control system

A method of controlling the air-fuel ratio of an internal combustion engine having an exhaust passage including a catalytic converter. The method includes providing a first air-fuel ratio sensor upstream of the catalytic converter, and providing a second air-fuel ratio sensor downstream of the catalytic converter. A control module having an input connected to the first and second air-fuel ratio sensors and an output connected to actuators for controlling the engine is also provided. This establishes a first feedback loop including the first air-fuel ratio sensor and a second feedback loop including the second air-fuel ratio sensor. The method further includes detecting an output value of the second air-fuel ratio indicative of a rich or lean exhaust gas air-fuel ratio. In response to the output value, the system monitors the engine mass airflow, and controls the duration of air-fuel ratio of the engine as a function of the engine mass airflow.

Air-fuel ratio feedback control

Air/fuel and ignition control of engine are used to more rapidly heat-up a catalytic converter. A control system generates a fuel command for fuel delivery to the engine based upon at least an amount of air inducted into the engine. The fuel command is corrected by a correction value so that the exhaust gas mixture is shifted more closely to the preselected air/fuel ratio. Correction values are adaptively learned during warm engine operation from a feedback signal derived from an exhaust gas oxygen sensor. Initial warm correction values are stored in a reference table. At engine shut-off the difference between the warm correction values and the reference table are stored in an offset correction table. This offset correction table is then used during the next engine cold start to schedule the open-loop air/fuel ratio by using the cold adaptive table values which have been modified by the values stored in the corresponding cells of the offset correction value table. In this way, any changes which occur in engine operating characteristics from the time the engine initially warms up to the time it is shut off are represented by the offset correction table.

Engine control system with adaptive cold-start air/fuel ratio control

A catalyst system employed in the exhaust stream of an internal combustion engine (10) wherein the catalyst deterioration is monitored by an engine controller (26) connected to a first oxygen sensor (22) mounted upstream of a catalyst (18) and a second oxygen sensor (24) mounted downstream. After a cold start of the engine (10) a calibration of the first and second sensors is conducted, to assure accuracy between the two sensors and determine if one of the sensors has failed, and also a light-off time for the catalyst (18) is determined as one way to measure the deterioration of the catalyst. After the engine (10) has warmed up to operating temperature, a test is run to determine the ability of the catalyst (18) to store oxygen therein, being another indication of catalyst deterioration.

Catalyst deterioration detection with sensor calibration

A catalyst system employed in the exhaust stream of an internal combustion engine (10) wherein the catalyst deterioration is monitored by an engine controller (26) connected to a first oxygen sensor (22) mounted upstream of a catalyst (18) and a second oxygen sensor (24) mounted downstream. After a cold start of the engine (10) a light-off time for the catalyst (18) is determined as one way to measure the deterioration of the catalyst. After the engine (10) has warmed up to operating temperature, a test is run to determine the ability of the catalyst (18) to store oxygen therein, being another indication of catalyst deterioration.

Catalyst deterioration monitoring

A catalyst system employed in the exhaust stream of an internal combustion engine (10) wherein the catalyst deterioration is monitored by an engine controller (26) connected to a first oxygen sensor (22) mounted upstream of a catalyst (18) and a second oxygen sensor (24) mounted downstream. After a cold start of the engine (10) a calibration of the first and second sensors is conducted, to assure accuracy between the two sensors and determine if one of the sensors has failed, and also a light-off time for the catalyst (18) is determined as one way to measure the deterioration of the catalyst.

Sensor calibration for catalyst deterioration detection

A hydrocarbon sensor measures the tail pipe hydrocarbon concentration emitted by an internal combustion engine to determine whether a catalyst has deteriorated beyond a predetermined point with respect to reducing hydrocarbon emissions. Catalyst performance is measured following an engine cold start when hydrocarbons are emitted and compared to catalyst performance when operating temperature has been reached to determine catalyst efficiency.

Catalyst monitoring using a hydrocarbon sensor

An engine air/fuel ratio control system maintains average engine air/fuel ratio at a desired lean air/fuel ratio during cold engine operation in order to more rapidly warm the catalytic converter. Fuel delivered to the engine is modulated with a truncated triangular wave which is truncated to minimize lean air/fuel excursions. An error signal is generated from the exhaust gas oxygen sensor output, and a proportional plus integral control responsive to the error signal generates a feedback correction value to maintain the desired air/fuel ratio. Gain of the controller is increased when the error signal indicates engine air/fuel operation leaner than a preselected air/fuel ratio to further minimize excursions in a fuel enleanment direction.

Lean air/fuel engine feedback control system

An engine air/fuel control system is disclosed which is responsive to first and second exhaust gas oxygen sensors respectively positioned upstream and downstream of a catalytic converter. Air/fuel feedback control is disabled, and a rich offset to fuel flow is provided to cause a corresponding rich offset in engine air/fuel ratio. A predetermined time afterwards, a lean offset in fuel flow is provided. Air/fuel feedback control is reinitiated, and fuel delivery is biased with a rich fuel bias when the downstream sensor indicates excessively lean engine exhaust in response to the lean fuel offset and biased with a lean fuel bias when the downstream sensor indicates excessively rich exhaust gases in response to the rich fuel offset.

Engine air/fuel control system with adaptively alignment of a catalytic

An air/fuel control system having a feedback variable generated by modulating fuel flow into the engine, generating an error signal from a difference between the average of an exhaust gas oxygen sensor output and a reference value correlated with a desired air/fuel ratio, and integrating the error signal. The reference value is periodically offset in both lean and rich air/fuel directions. A biasing signal is generated from an exhaust gas oxygen sensor position downstream of the converter in response to the air/fuel offset. After removing the offset from the reference value, the bias signal is applied thereto for centering engine air/fuel operation within the peak efficiency window of a catalytic converter.

Air/fuel control system for an internal combustion engine

A system and method to control the ignition timing of engine (28) are used to rapidly warm a catalytic converter (52). A controller (8) calculates (402) hydrocarbon efficiency of the converter (52) from a ratio of the integrals of hydrocarbon sensors respectively positioned downstream (48) and upstream (46) of the converter (52). The controller retards ignition timing to a value retarded from nominal ignition timing (416, 426) when the calculated hydrocarbon efficiency is less than a desired efficiency (418).

Engine control to achieve rapid catalyst warm-up

An air/fuel control system for an engine (10) provides an air/fuel indicating signal linearly related to average engine air/fuel operation from a two-state exhaust gas oxygen sensor (76). Fuel delivered to the engine is modulated with a periodic or modulation signal (244). The modulation signal is offset in either a fuel increasing or a fuel decreasing direction when the air/fuel indicating signal is respectively saturated at either a lean or a rich value (394-420).

Lean air/fuel control system for an internal combustion engine

An air/fuel control system for an engine (28) provides an air/fuel indicating signal linearly related to average engine air/fuel operation from a two-state exhaust gas oxygen sensor (44). Fuel delivered to the engine is modulated with a periodic signal (144). A reference value corresponding to a desired air/fuel ratio is subtracted from a rolling average of the exhaust gas oxygen sensor output to provide an error signal (148-152). A feedback variable (FV) for adjusting the engine air/fuel ratio is generated from a proportional plus integral controller having the error signal as its input (156). In this manner, average engine air/fuel ratio is maintained at the desired air/fuel ratio and the rolling average of the exhaust gas oxygen sensor output provides an air/fuel indicating signal.

Engine lean air/fuel control system

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Bloomfield, MI, United States of America

Douglas R Hamburg