Cummins Engine Company, Inc.

Keith L Musser

David A Olson

Michael J Ruth

Stephen M Holl

Daniel D Wilhelm

Gregory A Weber

Stephen West

David A Bolis

Jonathan A Stavnheim

Shyamala Raghunathan

James Hugh Ross

Jeffrey P Seger

Prakash Bedapudi

A fuel system includes an electronically controllable high pressure fuel pump operable to supply high pressure fuel from a lower pressure fuel source to a high pressure fuel collection chamber having a pressure sensor associated therewith. The fuel collection chamber feeds an electronically controllable valve operable to dispense the high pressure fuel to a fuel distribution unit supplying fuel to a number of fuel injectors. A control computer is provided for controlling the high pressure fuel pump and valve in response to requested fueling, engine speed and fuel pressure provided by the pressure sensor. The control computer is normally operable to drive the fuel pump as a function of fuel pressure and a reference pressure, which is based on requested fueling, and to control the valve as a function of commanded fueling, which is a function of engine speed and a reference speed based on requested fueling, and fuel pressure. In a first limp home mode, the control computer is operable to drive the fuel pump as a function of fuel pressure and commanded fueling if abnormal operation of the high pressure fuel pump is detected. In this mode, the valve is controlled only as a function of fuel pressure. In a second limp home mode, the control computer is operable to drive the fuel pump with a predicted fuel pump command based on the fuel command and engine speed, if abnormal operation of the pressure sensor is detected. In this mode, the valve is controlled as a function of the fuel command and the reference pressure or a default pressure.

Apparatus for controlling a fuel system of an internal combustion engine

A system for controlling fuel flow in an internal combustion engine receives a command specifying a desired fuel flow rate from an electronic control module. The system generates a feedforward estimate of actuator current required to produce the desired flow rate. This estimate is combined with a fueling current offset value generated using a proportional-integral feedback controller. A differential pressure between the fuel rail and cylinder gas is converted, by surface interpolation based on a lookup table, to an estimate of actual fuel flow rate. The difference between this actual fuel flow rate and the desired flow rate is provided to the feedback controller as an error signal. The feedback controller preferably uses different gain values depending on an operating mode of the engine (speed control and torque control modes).

Apparatus and method for accurately controlling fuel injection flow rate

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Cloumbus, IN, United States of America

Keith L Musser