Abstract: For at least one disturbance variable of the cylinder pressure signal, which disturbance variable occurs only during specific limited time spans as the pressure profile of an operating cycle, a filter tuned to the type of disturbance variable is fixed and is assigned to the corresponding disturbance variable time window or windows (8, 9, 10) in the operating cycle. The cylinder pressure signal (2) is then filtered as a function of the crankshaft angle, in that, according to the crankshaft position, a time-tuned and type-tuned filter is applied to a current disturbance variable.

Abstract: To determine the gas work WK from the areas formed by the cylinder pressure curve over the associated stroke volume V?, a cylinder-pressure-proportional integrator is started integrating the signals of the cylinder pressure sensor in multiple integrator runs depending on a settable integrator capacitance. A lower and an upper threshold value are predefined, whose difference corresponds to the integrator capacitance. Upon reaching one of the threshold values, respective new integrator runs are started, at the beginning and end of which the current crankshaft angle ? (is detected, respectively. For each integrator run, the associated individual work is determined depending on the product of the integrator capacitance and the particular covered stroke volume and the gas work resulting from the cylinder pressure curve is determined by summation of the individual works. The gas work may be used in particular for determining the internal mean pressure of the cylinder.

Abstract: For the direct re-entry in the CAI operating mode following a pull fuel cut off phase the CAI specific valve lift is maintained during its pull fuel cut off phase. Upon a request signal for the CAI re-entry after the closing time of the particular cylinder, an advance fuel injection quantity is injected in the combustion chamber and externally ignited and combusted in the following CAI interim compression phase of the exhaust stroke, as a result of which hot exhaust gas is formed in the combustion chamber, fresh air is drawn into the combustion chamber during the following intake stroke, a main fuel injection quantity is injected in a main compression phase during the following compression stroke, and the exhaust gas content brought about from the earlier auxiliary fuel injection, is mixed with the air-fuel mixture newly introduced for the main ignition to form a self-ignitable, homogenous fresh air-exhaust gas-fuel mixture.

Abstract: In order to control an internal combustion engine according to the invention, a polytropic exponent is determined in accordance with at least two measured values of the pressure in the combustion chamber of the cylinder, said measured values being detected after closing the gas discharge valve and before successively opening the gas intake valve. An exhaust gas mass which is located in the cylinder after closing the gas discharge valve and before successively opening the gas intake valve is determined according to the polytropic exponent at an estimated value of the pressure after closing the gas discharge valve and before successively opening the gas intake valve as well as at a certain temperature of the exhaust gas located in the cylinder after closing the gas discharge valve and before successively opening the gas intake valve. An actuation signal for controlling an actuating member of the internal combustion engine is generated in accordance with the determined exhaust gas mass.

Abstract: In a process and device for determining the composition of a gas mixture of the fuel tank of a motor vehicle filled with a CNG gas, the measured values of a pressure sensor and a temperature sensor, which are generally present in conventional fueled motor vehicles, are used to determine the vapor pressure (pd) of at least one of the gases in the gas mixture, in particular ethane, propane and/or butane. If the vapor pressure of one of the components of the CNG gas in the fuel tank falls short, then one relevant, current composition of the gas mixture is determined. This offers the advantage in an internal combustion engine that as much gas can always be injected with the 20 requisite energy value, as is called for by the specified air-fuel ratio (?-value) and the conditions of operation. This achieves optimum combustion with minimal exhaust.

Abstract: According to the invention, prior to or during an intermediate compression around the upper dead center of a piston of an internal combustion engine during a change in charge a predetermined first fuel mixture is metered into the combustion chamber of the respective cylinder. During the intermediate compression, measured values of pressure in the combustion chamber are measured in a predetermined first crankshaft angle window using cylinder pressure sensor. A measurement for a conversion rate of the first fuel mixture is determined based on the detected measured values of the pressure and reference values of the pressure, which characterize the corresponding pressure curve in the combustion chamber when no fuel is metered. A control signal for at least one actuator of the internal combustion engine is determined based on the conversion rate.

Abstract: The isentropic exponent (?) and the constant (k) in the equation p·V?=k for processes before and after fuel combustion in the cylinder are determined on the basis of the signals from a cylinder pressure sensor and from a crankshaft sensor. Cylinder pressures (p) before and after fuel combustion can be determined through the equation with the corresponding isentropic exponents (?) and corresponding constants. During fuel combustion, cylinder pressure (p) is sensed by the cylinder pressure sensor. The ratio between the fuel mass burned in the cylinder of the internal combustion engine and the fuel mass (MBR) supplied to the cylinder is determined on the basis of the above-mentioned variables. The process has the advantage of reducing the computation outlay necessary to determine the ratio between the fuel mass burned in the cylinder of the internal combustion engine and the fuel mass (MBR) supplied to the cylinder.

Abstract: The invention is directed toward a device for controlling an internal combustion engine. An aspect of the invention is determining a polytropic exponent according to at least two measured values of the pressure in a combustion chamber of a cylinder of an internal combustion engine during the working stroke of the cylinder once an air/fuel mixture of a cylinder has been burned and before the gas discharge valve is opened. A first exhaust gas temperature is determined and a second temperature of the exhaust gas is determined in accordance with the first exhaust gas temperature. The pressure associated in the combustion chamber, the pressure prevailing in the combustion chamber after closing the gas discharge valve, and the polytropic exponent are determined. An actuation signal for controlling an actuating member of the internal combustion engine is generated according to the second temperature of the exhaust gas.

Abstract: The invention relates to a system and method for use in a homogeneous charge compression ignition (HCCI) combustion engine that is preferably equipped with an exhaust gas recirculation device. This system and method enable an improved adjustment of the temperature level inside the combustion chamber. In addition to adjusting the temperature by using the exhaust gas recirculation device, an influencing of the temperature, which is independent thereof, ensues based on the compression of the induced fresh air by the exhaust gas turbocharger. An increase in temperature is maintained even after the compressed air is expanded on a throttle valve, and this increase in temperature can, in the end, be used for influencing the energy content inside the combustion chamber.

Abstract: In one aspect, a method for controlling an internal combustion engine using valve lift switchover is provided. Within the scope of this method, a switchover intake manifold model for the switchover-relevant pressure range for valve lift switchover is applied in addition to the use of a basic intake manifold model. This ensures a valve lift switchover with approximately constant torque of the internal combustion engine.

Abstract: This invention describes a method for optimizing a valve-lift changeover on spark-ignition engines with lambda control. On the basis of the evaluation of an acceleration characteristic and a lambda characteristic during the valve-lift changeover, it is determined whether cylinder charging errors and/or torque errors that require correction are present in the spark-ignition engine.

Abstract: According to the invention, prior to or during an intermediate compression around the upper dead center of a piston of an internal combustion engine during a change in charge a predetermined first fuel mixture is metered into the combustion chamber of the respective cylinder. During the intermediate compression, measured values of pressure in the combustion chamber are measured in a predetermined first crankshaft angle window using cylinder pressure sensor. A measurement for a conversion rate of the first fuel mixture is determined based on the detected measured values of the pressure and reference values of the pressure, which characterize the corresponding pressure curve in the combustion chamber when no fuel is metered. A control signal for at least one actuator of the internal combustion engine is determined based on the conversion rate.

Abstract: In one aspect, a method for controlling an internal combustion engine using valve lift switchover is provided. Within the scope of this method, a switchover intake manifold model for the switchover-relevant pressure range for valve lift switchover is applied in addition to the use of a basic intake manifold model. This ensures a valve lift switchover with approximately constant torque of the internal combustion engine.

Abstract: This invention describes a method for optimizing a valve-lift changeover on spark-ignition engines with lambda control. On the basis of the evaluation of an acceleration characteristic and a lambda characteristic during the valve-lift changeover, it is determined whether cylinder charging errors and/or torque errors that require correction are present in the spark-ignition engine.

Abstract: The present invention relates to a method for regulating deceleration of a motor vehicle. In the context of this method, braking torques generated by charging processes in the motor vehicle are compensated for by targeted actuation of gas exchange elements. By setting the deceleration of the vehicle achieved by charging processes at a certain desired value, a comfortable operation of the motor vehicle is achieved.

Abstract: The invention relates to a device for electrohydraulic valve lift switching with a hydraulically activatable actuating element for bringing about valve lift switching, which is connected to an oil line, whereby the action of pressurized oil on the actuating element can be controlled by an on/off valve arranged in the oil line and connected to a control device. The invention has an oil pressure metering device arranged in the oil line, which is connected to the control device, and a device for detecting the time period between activation of the on/off valve by the control device and a characteristic change in the measured oil pressure.

Abstract: The invention relates to a system and method for use in a homogeneous charge compression ignition (HCCI) combustion engine that is preferably equipped with an exhaust gas recirculation device. This system and method enable an improved adjustment of the temperature level inside the combustion chamber. In addition to adjusting the temperature by using the exhaust gas recirculation device, an influencing of the temperature, which is independent thereof, ensues based on the compression of the induced fresh air by the exhaust gas turbocharger. An increase in temperature is maintained even after the compressed air is expanded on a throttle valve, and this increase in temperature can, in the end, be used for influencing the energy content inside the combustion chamber.

Abstract: The invention relates to a method for regulating the mixture in an internal combustion engine by means of a catalytic converter and a lambda probe that is placed downstream of the catalytic converter. Depending on the historical signal values, said method determines whether intervention in the formation of the mixture is required, whether the existing signal is only decreasing slowly, which necessitates slow regulatory intervention, or whether the signal of the probe placed downstream of the catalytic converter decreases rapidly, which necessitates rapid regulatory intervention. The difference types of intervention enable the volume of the catalytic converter to be reduced, thus preventing high consumption in the warm-up phase or the poor start-up behavior of large catalytic converters.

Abstract: For an effectively working regulation of the combustion process in the HCCI mode, a modeled combustion process, to be described by internal variables of state, is formed by using process-influencing variables. Output variables of the actual and modeled combustion process are then used to regulate the process-influencing variables.

Abstract: Parameters of an actuation distance model are adapted for an exhaust turbocharger actuator. For this, in the stationary or quasi-stationary operating state of the internal combustion engine, a first actuator is activated in the exhaust tract. The parameters of the actuation distance model are adapted on the basis of a comparison of the actual and target values for a modified state variable at the turbine. The change brought about by activation of the first actuator is compensated by activation of a second actuator in the fresh air tract.