Interactive idle speed control with a direct fuel control

Claim 1

A method of controlling the idling speed of an internal combustion engine, said method comprising: generating a speed error signal as a function of the difference between a desired engine idle speed and the actual engine idle speed; generating a fuel pulse width command signal to control a fuel mass charge as a function of the speed error signal; generating a throttle command signal as a function of the fuel mass charge to maintain a desired air to fuel ratio; generating a spark advance; phase compensating the speed error signal with respect to time; generating a pressure error signal as the difference between a desired engine manifold pressure and an actual engine manifold pressure where desired engine manifold pressure is proportional to fuel charge and a function of air and coolant temperature; phase compensating the pressure error signal with respect to time; and wherein generating a fuel pulse width command signal includes summing a first signal proportional to the phase compensated speed error signal and a second signal proportional to the time integral of the speed error; and generating a throttle command signal includes summing a first signal proportional to the phase compensated pressure error signal and a second signal proportional to the time integral of the pressure error.

Claim 2

A method of controlling the idling speed of an internal combustion engine, said method comprising: generating a speed error signal as a function of the difference between a desired engine idle speed and the actual engine idle speed; generating a fuel pulse width command signal to control a fuel mass charge as a function of the speed error signal; generating a throttle command signal as a function of the fuel mass charge to maintain a desired air to fuel ratio; generating a spark advance; phase compensating the speed error signal with respect to time; generating a pressure error signal as the difference between a desired engine manifold pressure and an actual engine manifold pressure where desired engine manifold pressure is proportional to fuel charge and a function of air and coolant temperature; phase compensating the pressure error signal with respect to time; and wherein generating a fuel pulse width command signal includes summing a first signal proportional to the phase compensated speed error signal and a second signal proportional to the time integral of the speed error; and generating a throttle command signal includes summing a first signal proportional to the phase compensated pressure error signal and a second signal proportional to the time integral of the pressure error.

Claim 8

A method of controlling the idling speed of an internal combustion engine, said method comprising: generating a speed error signal as a function of the difference between a desired engine idle speed and the actual engine idle speed; generating a fuel pulse width command to control fuel charge as a function of the speed error signal; sensing actual intake manifold pressure; generating a desired intake manifold pressure; and comparing actual and desired intake manifold pressure to get a difference which is used to generate a throttle position command signal to maintain a desired air to fuel ratio.

Claim 9

A method of controlling the idling speed of an internal combustion engine, said method comprising: generating a speed error signal as a function of the difference between a desired engine idle speed and the actual engine idle speed; generating a fuel pulse width command to control fuel charge as a function of the speed error signal; sensing actual intake manifold pressure; generating a desired intake manifold pressure; and comparing actual and desired intake manifold pressure to get a difference which is used to generate a throttle position command signal to maintain a desired air to fuel ratio.

Claim 10

A method of controlling the idling speed of an internal combustion engine, said method comprising: generating a speed error signal as a function of the difference between a desired engine idle speed and the actual engine idle speed; generating a fuel pulse width command to control fuel charge as a function of the speed error signal; sensing an actual air signal representative of an actual air flow in the throttle of the internal combustion engine; generating a desired air signal representative of a desired air flow in the throttle of the internal combustion engine; determining an air flow error signal which is the difference between the desired and the actual air signals; and generating a throttle command signal to control air flow in the throttle by using the air flow error signal.

Claim 11

A method of controlling the idling speed of an internal combustion engine, said method comprising: generating a speed error signal as a function of the difference between a desired engine idle speed and the actual engine idle speed; generating a fuel pulse width command to control fuel charge as a function of the speed error signal; sensing an actual air signal representative of an actual air flow in the throttle of the internal combustion engine; generating a desired air signal representative of a desired air flow in the throttle of the internal combustion engine; determining an air flow error signal which is the difference between the desired and the actual air signals; and generating a throttle command signal to control air flow in the throttle by using the air flow error signal.