Adaptive learning control for engine intake air flow

Claim 2

An adaptive learning control method for regulating the quantity of intake air flowing into a fuel injected internal combustion engine to achieve a scheduled air-fuel ratio, where the amount of fuel supplied to each engine cylinder is determined directly as a function of the operator demand for engine output, with the engine having a plurality of operating regions defined by its operating parameters, the steps of the method comprising: deriving an indication of the actual mass of air inducted into each engine cylinder; deriving an indication of a desired mass of air for each engine cylinder, which corresponds to the scheduled air-fuel ratio; determining the region in which the engine is operating based upon the engine operating parameters; obtaining a value for a previously stored learning correction that corresponds to the region in which the engine is operating; adjusting the quantity of intake air flowing into the engine as a function of at least the learning correction value, to reduce the difference between the indications for the actual and desired mass of air for each engine cylinder; and updating the value of the stored learning correction as a function of the difference between the indications for the actual and desired mass of air for each engine cylinder.

Claim 3

The method described in claim 1, wherein the stored learning coefficient is updated, when the engine continuously operates in the region and a predetermined time has elapsed since the engine first began continuous operation in the region.

Claim 4

The method described in claim 1, wherein the indication for the desired mass of air for each engine cylinder is derived as a function of at least the amount of fuel supplied to each cylinder.

Claim 5

The method described in claim 1, wherein the indication for the desired mass of air for each engine cylinder is derived as a function of at least the amount of fuel supplied to each each cylinder and the rotational speed of the engine.

Claim 6

The method described in claim 1, wherein the step of deriving the indication of the actual mass of air inducted into each engine cylinder includes sensing the mass air flow into the engine.

Claim 7

The method described in claim 1, wherein the step of deriving the indication of the actual mass of air inducted into each engine cylinder includes sensing the engine operating air-fuel ratio.

Claim 8

An adaptive learning control method for regulating the quantity of intake air flowing into a fuel injected internal combustion engine to achieve a scheduled air-fuel ratio, where the amount of fuel supplied to each engine cylinder is determined directly as a function of the operator demand for engine output, with the engine having a plurality of operating regions defined by its operating parameters, the steps of the method comprising: sensing the rotational speed of the engine; deriving an indication of the actual mass of air inducted into each engine cylinder; deriving an indication of a desired mass of air for each engine cylinder, which corresponds to the scheduled air-fuel ratio; determining the region in which the engine is operating based upon the engine operating parameters; determining an open-loop value for controlling engine air flow based upon the rotational speed of the engine and the indication for the desired mass of air for each engine cylinder; determining a closed-loop value for controlling engine air flow based upon the difference between the indications for the actual and desired mass of air for each engine cylinder; obtaining a value for a previously stored learning correction that corresponds to the region in which the engine is operating; adjusting the quantity of intake air flowing into the engine in accordance with the sum of the open-loop value, the closed-loop value, and learning correction value; and updating the value of the stored learning correction periodically, as a function of the difference between the indications of actual and desired mass of air for each engine cylinder, when the engine continuously operates in the region and a predetermined time has elapsed since the engine first began continuous operation in the region.

Claim 9

An adaptive learning control method for regulating the quantity of intake air flowing into a fuel injected internal combustion engine to achieve a scheduled air-fuel ratio, where the amount of fuel supplied to each engine cylinder is determined directly as a function of the operator demand for engine output, with the engine having a plurality of operating regions defined by its operating parameters, the steps of the method comprising: sensing the rotational speed of the engine; deriving an indication of the actual mass of air inducted into each engine cylinder; deriving an indication of a desired mass of air for each engine cylinder, which corresponds to the scheduled air-fuel ratio; determining the region in which the engine is operating based upon the engine operating parameters; determining an open-loop value for controlling engine air flow based upon the rotational speed of the engine and the indication for the desired mass of air for each engine cylinder; determining a closed-loop value for controlling engine air flow based upon the difference between the indications for the actual and desired mass of air for each engine cylinder; obtaining a value for a previously stored learning correction that corresponds to the region in which the engine is operating; adjusting the quantity of intake air flowing into the engine in accordance with the sum of the open-loop value, the closed-loop value, and learning correction value; and updating the value of the stored learning correction periodically, as a function of the difference between the indications of actual and desired mass of air for each engine cylinder, when the engine continuously operates in the region and a predetermined time has elapsed since the engine first began continuous operation in the region.

Claim 10

The method described in claim 7, wherein the stored learning correction is periodically updated based upon the integration of the difference between the indications for the actual and desired mass of air for each engine cylinder.

Claim 11

The method described in claim 7, wherein the indication for the desired mass of air for each engine cylinder corresponding to the scheduled air-fuel ratio is derived at least as a function of the amount of fuel supplied to each cylinder.

Claim 12

The method described in claim 7, wherein the indication for the desired mass of air for each engine cylinder is derived as a function of at least the amount of fuel supplied to each cylinder and the rotational speed of the engine.

Claim 13

The method described in claim 7, wherein the step of deriving the indication of the actual mass of air inducted into each engine cylinder includes sensing the mass air flow into the engine.

Claim 14

The method described in claim 7, wherein the step of deriving the indication of the actual mass of air inducted into each engine cylinder includes sensing the engine operating air-fuel ratio.