A method for the model-based open-loop and closed-loop control of an internal combustion engine includes the steps of: during stationary operation, switching takes place cyclically from the normal operation to an exploration operation, wherein in the exploration operation, an exploration measure of quality (J/EXP) is calculated in accordance with combustion model and variance (VAR) thereof, wherein the exploration measure of quality (J/EXP) is set as essential for the operating point of the internal combustion engine, wherein on the basis of the operating variables of the internal combustion engine combustion model is adapted, and wherein switching back to normal operation takes place.

A method and a device for ascertaining a fluid injection quantity of an injection system. The injection system includes a high-pressure pump, a high-pressure region that adjoins the high-pressure pump, a pressure sensor, and an injector that is fed from the high-pressure region. The method includes detecting a measurement signal using the pressure sensor and segmenting a first pressure profile from the measurement signal. The first pressure profile characterizes the pressure profile prior to a fluid injection using the injector. The method also includes segmenting a second pressure profile from the measurement signal. The second pressure profile characterizes the pressure profile after the fluid injection using the injector. The method also includes performing a core density estimation using the first pressure profile and the second pressure profile, ascertaining a pressure difference, and ascertaining the fluid injection quantity using the pressure difference.

A controller for a common-rail injection system includes a plurality of fuel injectors, a common fuel supply line for the fuel injectors, a high-pressure pump for supplying the common fuel supply line with fuel, and a pressure sensor for determining the pressure in the common fuel supply line. A determination unit evaluates data of the pressure sensor and, from the pressure drop caused by an injection in the common fuel supply line, determines the fuel quantity actually injected during this injection or a value derived therefrom. An adaption unit uses the results of the determination unit in order to adapt the actuation of the fuel injectors. The determination unit carries out at least one test injection, and the actually injected fuel quantity or a value derived therefrom is effected by way of the test injection or injections.

A microcomputer determines that an abnormality has occurred in calculation functions regarding calculation of an injection amount command value and the like, based on a deviation of the injection amount command value, in an increasing manner, from a monitoring injection amount. The microcomputer calculates, based on a cooling fluid temperature of an engine, a start-up injection amount such that the start-up injection amount becomes smaller when the cooling fluid temperature is high than when the cooling fluid temperature is low, and uses the start-up injection amount as the injection amount command value immediately after the completion of start-up of the engine. Besides, the microcomputer uses the smaller one of a start-up injection amount calculated this time and a monitoring start-up injection amount calculated last time, as a monitoring start-up injection amount that is used as the aforementioned monitoring injection amount immediately after the completion of start-up of the engine.

An ECU has a fuel pressure sensor that detects fuel pressure inside of a common rail. The ECU detects the fuel pressure at a predetermined frequency and calculates a drop amount of the fuel pressure in accordance with fuel injection by fuel injectors based on the detected fuel pressure. The ECU acquires a fluctuation amount of a fuel injection amount of each of the fuel injectors based on the drop amount of the fuel pressure and learns an injection characteristic of each of the fuel injectors, the injection characteristic indicating a correlation between the fuel injection amount and the fluctuation amount of the fuel injection. In a case in which a detection timing of the fuel pressure is within a fuel injection period of a predetermined fuel injector, the ECU disallows the learning of the injection characteristic using the fuel pressure detected in the fuel injection period.

A control apparatus is disclosed for operating a fuel injector of an internal combustion engine. The control apparatus includes an Electronic Control Unit configured to: perform a first calculation task in order to calculate a set of Start Of Injection values (SOI.sub.i) of a train of injections, calculate an angular position (DIAngPos) of the crankshaft defining the start of a second calculation task, and perform the second calculation task in order to calculate a set of values (ET.sub.i) of the energizing time of the injections of the train. The angular position (DIAngPos) is calculated as a function of the Start Of Injection value (FirstSOI) of the first injection of the train as calculated by the first calculation task.

An engine control system includes first and second control modules. The first control module determines a fuel combustion parameter. The second control module determines a fuel delivery parameter based on the fuel combustion parameter. The fuel combustion parameter includes at least one of (i) a total amount of heat released by a volume of fuel during a combustion cycle and (ii) a rate at which heat is released during the combustion cycle. The fuel delivery parameter includes at least one of (i) a duration of time over which the volume of fuel is delivered to a cylinder, (ii) a time at which a fuel injector starts delivering the volume of fuel to the cylinder, and (iii) a fuel pressure in a fuel rail.

The invention relates to a method for testing an electrically activated actuator in a fuel delivery device (10) of an internal combustion engine, wherein the electrical actuator is a controllable valve (15) that is arranged on the inlet side of a high-pressure pump (16). The high-pressure pump (16) conveys fuel into a fuel store (17) having a pressure controller (20). The fuel store (17) is connected to at least one injector (23). The method comprises the following steps: 1) increasing the rotational speed of the high-pressure pump (16), 2) activating the controllable valve (15) until the pressure in the fuel store (17) has reached a first low pressure level, 3) changing the supply of current to the controllable valve (15) by a first specified value such that the controllable valve (15) is opened further and simultaneously maximizing an injection amount by means of the at least one injector (23) until the pressure in the fuel store (17) has reached a first threshold value, 4) activating the controllable valve (15) until the pressure in the fuel store (17) has reached the first low pressure level again, 5) determining a further quantity, which depends on the low pressure level and a maximum value of the pressure that was reached in the fuel store (17).

A fuel-supply system has a fuel pump, a pressure controller, a signal output device and a power switch. The pressure controller adjusts the observed fuel pressure of the fuel and may electronically communicate with a motor driving the fuel pump to regulate the supply of fuel from a fuel tank of the fuel-supply system to an engine. In detail, the pressure controller performs feedback control of a voltage applied to the motor such that the pressure of a fuel pumped from the fuel pump approaches to have a first target and/or ideal fuel pressure value. Further, the signal output device outputs the first target fuel pressure value to the pressure controller. Activation of the power switch supplies power, from a power source, to the pressure controller, the motor and the signal output device. Further, the pressure controller may perform feedback control based on a second target fuel pressure value.

The present invention provides a method for analyzing and optimizing the injection of fluid into an internal combustion engine via a common rail system. Once various injection parameters are determined for a given injection system, these data may be used to model the effect of sequential injection events for the system. A processer can then be used to run the model and to adjust sequential fuel injection events to optimize engine performance and fuel usage.