Engine airflow controller with feedback loop compensation for changes in engine operating conditions

Apparatus for controlling the airflow rate past a throttle plate of an engine, positioned in an intake of the engine, the apparatus comprising:

• means for generating an upstream air pressure value, indicative of air pressure upstream of a throttle plate;
• means for generating a downstream air pressure value, indicative of air pressure downstream of said throttle plate;
• means for generating an actual air mass flow rate value, indicative of the actual mass flow rate of air into said intake;
• means for generating an air temperature value, indicative of the temperature of said air entering said intake;
• means, responsive to said upstream air pressure value, said downstream air pressure value, said air temperature value and a desired air mass flow rate value, indicative of desired airflow past said throttle plate, for generating a predicted desired throttle angle value;
• means, responsive to said upstream air pressure value, said downstream air pressure value, said air temperature value and said actual air mass value, for generating a predicted actual throttle angle value;
• means, responsive to said predicted desired throttle angle value and to said predicted actual throttle angle value, for generating a throttle angle difference value;
• means, responsive to said throttle angle difference value, for generating a throttle angle change value;
• means, responsive to said throttle angle change value and to said predicted desired throttle angle value for generating a throttle angle control value, indicative of a position for said throttle;
• and
• means, for causing change of said throttle to a position which corresponds to said throttle angle control value.

An article of manufacture comprising:

• a computer storage medium having a computer program encoded therein for causing a computer to control a throttle angle of an electronically controlled throttle, said computer storage medium comprising:
• means for causing a computer to generate an upstream air pressure value, indicative of air pressure upstream of said throttle;
• means for causing a computer to generate a downstream air pressure value, indicative of air pressure downstream of said throttle;
• means for causing a computer to generate an actual air mass value, indicative of the actual mass flow rate of air into said intake;
• means for causing a computer to generate an air temperature value, indicative of the temperature of said air entering said intake;
• means for causing a computer to generate, as a function of said upstream air pressure value, said downstream air pressure value, said air temperature value and a desired airflow value, indicative of desired airflow past said throttle plate, a predicted desired throttle angle value;
• means for causing a computer to generate, as a function of said upstream air pressure value, said downstream air pressure value, said air temperature value and said actual air mass value, a predicted actual throttle angle value;
• means for causing a computer to generate, as a function of said predicted desired throttle angle value and said predicted actual throttle angle value, a throttle angle difference value;
• means for causing a computer to generate as a function of said throttle angle difference value, a throttle angle change value;
• and
• means for causing a computer to generate, as a function of said throttle angle change value and said predicted desired throttle angle value, a throttle angle control value, indicative of a position for said throttle;
• and
• means for causing a computer to transmit a throttle control signal to change said throttle to a position which corresponds to said throttle angle control value.