Control apparatus for operating a fuel metering valve
AssigneeGM Global Technology Operations LLC
InventorStefano Nieddu
Life of this patent
Estimating the term…
Abstract
A method and control apparatus are disclosed for operating a fuel-metering valve associated to a fuel pump arranged to supply fuel into a fuel rail, the fuel-metering valve having a valve member and an electric actuator arranged to move that member for regulating a fuel flow-rate. The control apparatus includes an electronic control unit connected to the fuel-metering valve and configured to implement a method of control using a target value, a nominal function corrected value to set an adjustable parameter of a control signal for the fuel-metering valve.
Claims14
1-13. (canceled)
A control apparatus for operating a fuel metering valve associated to a fuel pump arranged to supply fuel into a fuel rail, the fuel metering valve having a valve member and an electric actuator arranged to move the valve member for regulating a fuel flow-rate supplied by the fuel pump into the fuel rail, the control apparatus comprising an electronic control unit connected to the fuel metering valve and configured to:
- determine a target value (q*tot) for the fuel flow-rate;
- use a nominal function (Fn), correlating values of the fuel flow-rate to corresponding values of an adjustable parameter of an electric signal driving the actuator of the fuel metering valve, to determine a nominal value (rn) of the adjustable parameter that corresponds to the target value (q*tot) of the fuel flow-rate;
- use the determined nominal value (rn) to calculate a corrected value (r*) of the adjustable parameter;
- and
- set the adjustable parameter of the electric signal at the corrected value (r*);
- wherein the electronic control unit is configured to calculate the corrected value (r*) of the adjustable parameter by:
- estimating a value (q̂tot) of the fuel flow-rate that approximates a real value (qtot) thereof;
- calculating a difference between the target value (q*tot) and the estimated value (q̂tot) of the fuel flow-rate;
- using said difference to determine a value (Δr*) of a correction term indicative of a deviation of the nominal function (Fn);
- and
- calculating the corrected value (r*) of the adjustable parameter as a function of the nominal value (rn) thereof and of the calculated value (Δr*) of the correction term.
The control apparatus according to any of the claims from 14, wherein the adjustable parameter of the electric signal driving the actuator of the fuel metering valve is a timing of a sequence of electrical current pulses forming the signal.
A method for operating a fuel metering valve associated to a fuel pump arranged to supply fuel into a fuel rail, the fuel metering valve having a valve member and an electric actuator arranged to move the valve member for regulating a fuel flow-rate supplied by the fuel pump into the fuel rail, the method comprising:
- determining a target value (q*tot) for the fuel flow-rate;
- using a nominal function (Fn) correlating values of the fuel flow-rate to corresponding values of an adjustable parameter of an electric signal driving the actuator of the fuel metering valve, to determine a nominal value (rn) of the adjustable parameter that corresponds to the target value (q*tot) of the fuel flow-rate;
- using the determined nominal value (rn) to calculate a corrected value (r*) of the adjustable parameter;
- and
- setting the adjustable parameter of the electric signal at the corrected value (r*),
- wherein the corrected value (r*) of the adjustable parameter is calculated by:
- estimating a value (q̂tot) of the fuel flow-rate that approximates a real value (qtot) thereof;
- calculating a difference between the target value (q*tot) and the estimated value (q̂tot) of the fuel flow-rate;
- using said difference to determine a value (Δr*) of a correction term indicative of a deviation of the nominal function (Fn);
- and
- calculating the corrected value (r*) of the adjustable parameter as a function of the nominal value (rn) thereof and of the calculated value (Δr*) of the correction term.
Dependencies are inferred from the claim text.