초록 ▼

A method for controlling cylinder charge in a direct-injection, spark-ignition engine. The engine includes an intake manifold and an electronically controlled throttle (ETC) valve controlling air flow from the atmosphere to the intake manifold of said engine. The method includes: measuring an intake

A method for controlling cylinder charge in a direct-injection, spark-ignition engine. The engine includes an intake manifold and an electronically controlled throttle (ETC) valve controlling air flow from the atmosphere to the intake manifold of said engine. The method includes: measuring an intake manifold pressure value, P i ,; measuring a flow value, W thr,m , which is indicative of flow through the ETC throttle; determining a desired intake manifold pressure value, P i d ; determining a desired ETC valve position, u thr,d ; determining a desired flow, W thr d , through the ETC valve; and, adjusting said ETC valve position, u thr , in accordance with: said desired ETC valve position, u thr,d ; a difference between the measured intake manifold pressure value, P i , and the determined desired intake manifold pressure value, P i d ; and a difference between the measured flow value, W thr,m , through the ETC valve and the determined desired flow, W thr d . In-cylinder and throttle body adaptation is also provided.

대표청구항 ▼

1. A method is provided for controlling cylinder charge in a direct-injection, spark-ignition engine, such engine having an intake manifold and an electronically controlled throttle (ETC) valve controlling air flow from the atmosphere to the intake manifold of said engine, such method comprising:(A)

1. A method is provided for controlling cylinder charge in a direct-injection, spark-ignition engine, such engine having an intake manifold and an electronically controlled throttle (ETC) valve controlling air flow from the atmosphere to the intake manifold of said engine, such method comprising:(A) measuring an intake manifold pressure value, P i ,;(B) measuring a flow value, W thr,m , indicative of flow through the ETC valve;(C) determining a desired intake manifold pressure value, P i.d ;(D) determining a desired flow, W thr,d , through the ETC valve;(E) determining a desired ETC valve position, u thr, d; and,(F) adjusting said ETC valve position, u thr , in accordance with:(i) said desired ETC valve position, U thr,d ;(ii) a difference between the measured intake manifold pressure value, P i , and the determined desired intake manifold pressure value, P i,d ; and(iii) a difference between the measured flow value, W thr,m , through the ETC valve and the determined desired flow, W thr.d . 2. A method for controlling cylinder charge in a direct-injection, spark-ignition engine, such engine including an intake manifold and an electronically controlled throttle (ETC) valve for controlling air flow from the atmosphere to the intake manifold of said engine, such method comprising:parameterizing air flow through the ETC valve as: W thr =β thr 0 +β thr 1 {overscore (W)} thr where: β thr 0 and β thr 1 are estimator parameters; {overscore (W)} thr is a nominal predicted flow through the ETC valve, such predicted flow being a function of measured ETC valve position and measured intake manifold pressure;determining differences between the measured flow through the ETC valve and the predicted flow through the ETC valve;modifying the estimator parameters in accordance with the determined differences; andproviding a desired air flow through the ETC valve by adjusting the ETC valve position, U thr , in accordance with the parameterized air flow, such parameterized air flow being a function of the estimator parameters. 3. The method recited in claim 2 wherein the nominal predicted flow is determined from the standard orifice flow equation. 4. The method recited in claim 2 wherein the estimator parameters are modified in accordance with:where: thr =W thr,m −Ŵ thr ; Ŵ thr ={circumflex over (β)} thr 0 +{circumflex over (β)} thr 1 Ŵ thr andγ thr 0 , γ thr 1 , are adaptation gains, t+T a is a time such adaptation parameters are updated, and W thr,m is measured flow through the ETC valve. 5. The method recited in claim 4 wherein the nominal predicted flow is determined from the standard orifice flow equation. 6. The method recited in claim 2 wherein the prediction is disabled when the intake manifold pressure is relatively high and the ETC valve is experiencing a relatively large transient condition. 7. The method recited in claim 4 wherein a dead zone is applied to ε thr before it is used. 8. The method recited in claim 4 wherein the adaptation gains are reduced at high intake manifold pressures. 9. A method for controlling air charge in a direct-injection, spark-ignition engine, such engine having an exhaust gas recirculation (EGR) valve connecting the exhaust manifold and intake manifold of the engine and an electronically controlled throttle (ETC) valve controlling air flow from the atmosphere to the intake manifold of said engine, such method comprising:(A) providing an estimator for estimating flow through the EGR valve;(B) during a calibration mode:(i) applying a step function to the estimator, such estimator having a dynamic response characteristic to the applied step function, such dynamic response characteristic being a function of a parameter in such estimator;(ii) comparing the dynamic response characteristic of the estimator to the step function to the dynamic response characteristic provided in accordance with the orifice equation applied to the intake throttle and the EGR valve; and(iii) adjusting the parameter of the estimator to a value where the dynamic response characteristic provided by the estimator to the dynamic response characteristic provided by the estimator are substantially match to a predetermined response; and(C) during a subsequent normal operating mode:(i) removing the step function; and(ii) using the estimator value to estimate flow through the EGR valve. 10. A method for controlling air charge in a direct-injection, spark-ignition engine, such engine having an exhaust gas recirculation (EGR) valve connecting the exhaust manifold and intake manifold of the engine and an electronically controlled throttle (ETC) valve controlling air flow from the atmosphere to the intake manifold of said engine, such method comprising:(A) measuring an intake manifold pressure value which is indicative of measured intake manifold pressure;(B) estimating flow into the cylinder as a function of the measured intake manifold pressure;(C) modifying the estimated flow into the cylinder with a time varying multiplier; and(D) determining, when the EGR valve is opened, the time varying multiplier as a function of the difference between measured flow through the ETC and the modified estimated flow into the cylinder with a previously determined multiplier.