Ford Global Technolgoies, LLC

Lyth Alobiedat

Gopichandra Surnilla

Christopher Paul Glugla

Imtiaz Ali

Thomas George Leone

Michael Howard Shelby

Mohannad Hakeem

Richard E Soltis

Daniel A Makled

Michael Mcquillen

John Eric Rollinger

Stephen B Smith

Timothy Joseph Clark

Paul A Baltusis

Methods and systems are provided for estimating an actual compression ratio of an engine cylinder based on the electric current applied to an actuator of the associated variable compression ratio mechanism. The compression ratio is estimated as a function of both a value and a location, relative to cylinder piston position, of a peak holding current applied by an electric motor on the actuator to maintain the actuator at a commanded compression ratio setting. In this way, the vehicle control system may more accurately infer the current actual compression ratio of each cylinder.

Method for variable compression ratio engine

Methods and systems are provided for improving calibration of a variable compression ratio engine. Cylinder-to-cylinder compression ratio variations are detected and accounted for by comparing cylinder fuel flow and IMEP at each compression ratio setting. Dilution parameters including EGR and VCT schedule are also calibrated to account for the cylinder-to-cylinder compression ratio variations.

System and method for variable compression ratio engine

Systems and methods for operating an engine that includes a compression ratio linkage for adjusting engine compression ratio are described. The systems and methods provide different ways of changing a compression ratio of an engine based on forecast or anticipated engine operating conditions. In one example, the forecast or anticipated engine operating conditions may include a forecast or anticipated transmission gear shift.

Methods and system for operating an engine

Systems and methods for operating an engine that includes a compression ratio linkage for adjusting engine compression ratio are described. The systems and methods provide different ways of diagnosing the presence or absence of engine misfire in response to engine operating regions that may be more or less prone to torsional engine crankshaft vibration. In one example, engine misfire may be determined responsive to force applied to an engine compression ratio changing linkage.

Methods and systems for diagnosing operation of a compression ratio adjusting mechanism are described. In one example, an output of a pressure sensor is sampled and an assessment of the engine's present compression ratio is made after adjusting sampling of the output. Engine operation may be adjusted responsive to whether or not degradation of the compression ratio adjusting mechanism is indicated.

Method and system for diagnosing operation of an engine compression ratio changing mechanism

Methods and systems are provided for triggering a humidity measurement based on changes in ambient conditions. In one example, a method may include, in response to a higher than threshold change in ambient air temperature or pressure, operating an oxygen sensor to update an ambient humidity estimate. Engine operation parameters may be adjusted based on the updated ambient humidity estimate.

Method for humidity measurement enablement

A method for an engine may comprise, responsive to a first condition comprising a reference voltage of a first exhaust oxygen sensor operating in variable voltage mode increasing above a threshold voltage, determining a change in an output of the first exhaust oxygen sensor corresponding to the increase in the reference voltage, correcting the output of the first oxygen sensor based on the output change, and adjusting engine operation based on the corrected output. In this way, the accuracy of air-fuel estimates based on the exhaust gas sensor can be preserved, and closed loop fuel control of the engine can be maintained even when the exhaust oxygen sensor is operating VVS mode, thereby reducing engine emissions, increasing fuel economy, and increasing vehicle drivability.

Growing community of inventors

Detroit, MI, United States of America

Lyth Alobiedat