METHOD AND DEVICE FOR OPERATING AN INTERNAL COMBUSTION ENGINE
First Claim
1. A method for operating an internal combustion engine with an intake system and an exhaust gas system, which communicate with a combustion chamber of the internal combustion engine as a function of the switching position of a gas inlet valve or gas outlet valve, the intake system has at least an intake manifold and a throttle valve and a load sensor and the exhaust gas system has at least a lambda probe,the method comprising the steps of:
- when intake manifold model trimming is active;
detecting actual values of a load variable by means of the load sensor at different stationary throttle valve pressure ratios, which are representative of a difference between an intake manifold pressure upstream of the throttle valve and downstream of the throttle valve and estimated values of the load variable are also modeled based on an intake manifold model,determining trimming values of at least one model parameter of the intake manifold model as a function of the detected actual values and the modeled estimated values of the load variable in such a manner that when the corresponding model parameter is trimmed as a function of the trimming values the modeled estimated values of the load variable approximate to the corresponding detected actual values of the load variable,determining a trimming value best-fit function as a function of the different throttle valve pressure ratios and is approximated by the trimming values,detecting first controller values of first controller deflections of a lambda controller at different stationary throttle valve pressure ratios, anddetermining a first controller value best-fit function as a function of the throttle valve pressure ratios, which is approximated by the first controller values,when intake manifold model trimming is inactive;
detecting second controller values of second controller deflections of the lambda controller at different stationary throttle valve pressure ratios, anddetermining a second controller value best-fit function as a function of the throttle valve pressure ratios, which is approximated by the second controller values, andidentifying an error in the intake system as a function of the best-fit functions.
2 Assignments
0 Petitions
Accused Products
Abstract
Actual values of a load variable are detected by a sensor during active model trimming under different valve pressure conditions, and a model of estimated values is created. Trimming values of a model parameter are determined depending on detected and modeled values such that when the model parameter is trimmed, the modeled values approximate the detected values. A function is determined depending on the different pressure conditions and approximated to the trimming values. At different pressure conditions first lambda control values are detected. A first controller value fitted function is determined depending on the pressure conditions and approximated. When the model trimming mode is not active, second lambda control values are detected at different pressure conditions. A second controller value fitted function is determined depending on the pressure conditions and is approximated. An error of the intake system is detected depending on the fitted functions.
23 Citations
20 Claims
-
1. A method for operating an internal combustion engine with an intake system and an exhaust gas system, which communicate with a combustion chamber of the internal combustion engine as a function of the switching position of a gas inlet valve or gas outlet valve, the intake system has at least an intake manifold and a throttle valve and a load sensor and the exhaust gas system has at least a lambda probe,
the method comprising the steps of: -
when intake manifold model trimming is active; detecting actual values of a load variable by means of the load sensor at different stationary throttle valve pressure ratios, which are representative of a difference between an intake manifold pressure upstream of the throttle valve and downstream of the throttle valve and estimated values of the load variable are also modeled based on an intake manifold model, determining trimming values of at least one model parameter of the intake manifold model as a function of the detected actual values and the modeled estimated values of the load variable in such a manner that when the corresponding model parameter is trimmed as a function of the trimming values the modeled estimated values of the load variable approximate to the corresponding detected actual values of the load variable, determining a trimming value best-fit function as a function of the different throttle valve pressure ratios and is approximated by the trimming values, detecting first controller values of first controller deflections of a lambda controller at different stationary throttle valve pressure ratios, and determining a first controller value best-fit function as a function of the throttle valve pressure ratios, which is approximated by the first controller values, when intake manifold model trimming is inactive; detecting second controller values of second controller deflections of the lambda controller at different stationary throttle valve pressure ratios, and determining a second controller value best-fit function as a function of the throttle valve pressure ratios, which is approximated by the second controller values, and identifying an error in the intake system as a function of the best-fit functions. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A device for operating an internal combustion engine, comprising an intake system and an exhaust gas system, which communicate with a combustion chamber of the internal combustion engine as a function of the switching position of a gas inlet valve or a gas outlet valve, the intake system comprising at least an intake manifold and a throttle valve and a load sensor and the exhaust gas system comprising at least a lambda probe,
the device being operable when intake manifold model trimming is active: -
to detect actual values of a load variable by means of the load sensor at different stationary throttle valve pressure ratios, which are representative of a difference between an intake manifold pressure upstream of the throttle valve and downstream of the throttle valve and to model estimated values based on an intake manifold model; to determine trimming values of at least one model parameter of the intake manifold model as a function of the detected actual values and the modeled estimated values of the load variable in such a manner that when the corresponding model parameter is trimmed as a function of the trimming values the modeled estimated values of the load variable approximate to the corresponding detected actual values of the load variable, to determine a trimming value best-fit function as a function of the different throttle valve pressure ratios, which is approximated by the trimming values, to detect first controller values of first controller deflections of a lambda controller at different stationary throttle valve pressure ratios, and to determine a first controller value best-fit function as a function of the throttle valve pressure ratios, which is approximated by the first controller values, when intake manifold model trimming is inactive; to detect second controller values of second controller deflections of the lambda controller at different stationary throttle valve pressure ratios, and to determine a second controller value best-fit function as a function of the throttle valve pressure ratios, which is approximated by the second controller values, and the device being further operable to identify an error in the intake system as a function of the best-fit functions. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20)
-
Specification