According to the invention, a method for air path control of a combustion engine is provided, comprising an EGR valve and a VGT turbine. The method comprises providing a cost function of a measured delta pressure between engine intake and exhaust manifold; determining a gradient of the cost function as a function of a delta pressure set point, determining a gradient of a constraint function for estimated NOx emission level, turbine rate; and oxygen level as a function of delta pressure; real time controlling the NOx emission level and delta pressure to respective desired NOx and delta pressure set points by adjusting the EGR valve and/or the VGT turbine, wherein the delta pressure set point is adjusted according to an integration of a selected gradient direction of the cost function selected from the determined one or more of the gradients, wherein the determined gradients are prioritized in the order of turbine rate, oxygen level and NOx emission level; and wherein NOx emission level and or a turbine rate and or oxygen levels are constrained; and wherein the adjusted delta pressure set point is perturbed in an extremum seeking operation on the cost function.

The invention relates to a method for operating an internal combustion engine installed in a vehicle, in particular a diesel engine, in which the instantaneous concentration of a pollutant contained in the exhaust gas, in particular the NO.sub.x concentration in the exhaust gas, is measured or calculated in the flow direction after an exhaust gas aftertreatment. Using the determined pollutant concentration, the predefined distance- and/or power-based compliance with pollutant limiting values in mg/km or mg/kWh are monitored by means of specifically influencing the operating parameters of the internal combustion engine and/or an exhaust gas after treatment system in regulated form.

The invention relates to an internal combustion engine comprising a crankshaft, one or mor cylinders including a cylinder head, a piston, a combustion chamber, one or more intake valves, one or more exhaust valves, an intake system configured for feeding intake air to the engine, an exhaust system configured for conveying exhaust gas away from the engine, a pressure charging system connected to the intake system and an exhaust gas recirculation (EGR) system arranged to feed branched off exhaust gas from the exhaust system to the intake system via an EGR conduit wherein:—the internal combustion engine includes a valve actuation device configured to allow for late or early closing of the intake valves in accordance with late or early Miller-type valve timing, and wherein—the EGR system includes a gas feeding device configured to feed exhaust gas through the EGR conduit in modes of operation wherein the pressure in the intake system exceeds the pressure in the exhaust system. Additionally, a method of improving efficiency of an internal combustion engine is described.

To provide a controller and a control method for an internal combustion engine capable of calculating a target value of controlled variable of internal combustion engine which realizes the target torque, while reducing the number of calculations using a torque characteristics function. A controller and a control method for an internal combustion engine calculates ignition sample numbers of ignition corresponding torques corresponding to the respective ignition sample numbers of ignition timings, by using a torque characteristics function relationship in which a relationship between driving condition and output torque is preliminarily set; and calculates an ignition torque approximated curve approximating a relationship between the ignition sample numbers of the ignition timings and the ignition sample numbers of the ignition corresponding torques; and calculates a target ignition timing corresponding to the target torque.

An engine management system and method may include a control system and method for controlling an internal combustion engine. The internal combustion engine may be a direct-injection engine using a Sonex Controlled Auto-Ignition (“SCAI”) combustion path. The control system and method may utilize fuel injection pressure, timing of start and end of injection, management of turbo airflow, fuel supplied, and other factors to provide reduced emissions and improved performance.

A method of selective hydrocarbon injection in in-cylinder late post injection in an exhaust manifold of a diesel engine comprises providing the exhaust manifold of the diesel engine comprising a plurality of cylinders, an exhaust gas recirculation valve disposed adjacent the exhaust manifold, a diesel particulate filter disposed adjacent the exhaust manifold, an exhaust gas recirculation cooler disposed adjacent the exhaust manifold offset from the exhaust gas recirculation valve, and an engine control unit operatively connected with the diesel engine for controlling at least the plurality of cylinders. At least a first cylinder is disabled via the engine control unit to reduce post injection of hydrocarbons during regeneration of the diesel particulate filter. The diesel particulate filter is regenerated. In-cylinder late post injection of hydrocarbons is conducted during regeneration of the diesel particulate filter via cylinders other than the first cylinder.

Methods and apparatuses for calibration and control of various engine subsystems using a target value approach. Under the target value approach, the control of each engine subsystem is separated or decoupled to include a set of target values, or a reference value set. A subsystem has a corresponding target determiner, which provides a target value set, or reference value set, in response to a basis variable set and optionally an overall subsystem target. The basis variable set includes parameters selected to robustly characterize the variables that affect the operation of the particular subsystem. The target determiner is optionally calibrated to provide a reference value set within specifications of the subsystem. A physical subsystem controller operates in response to the reference value set.

Various methods and systems are provided for an exhaust gas recirculation system. In one embodiment, an engine method comprises routing exhaust gas from a first cylinder group of an engine to an exhaust gas recirculation passage coupled to both an intake passage and an exhaust passage of the engine, the first cylinder group having a first amount of positive intake and exhaust valve overlap, and routing exhaust gas from a second cylinder group of the engine only to the exhaust passage of the engine, the second cylinder group having a second, smaller amount of positive intake and exhaust valve overlap.

An internal combustion engine having two “banks” of cylinders, the “banks” being defined by cross-connection to different turbochargers. The exhaust from one bank of cylinders goes to a first turbocharger, and the exhaust from the other bank of cylinders goes to a second turbocharger. However, the compressed air delivered from the turbochargers is cross-connected to the cylinder banks. This allows a cylinder bank to be boosted with a turbocharger whose compressed air output does not necessarily match the exhaust energy of that cylinder bank.

A control apparatus for an engine includes an engine, a state quantity setting device, a spark plug, and a controller. The spark plug ignites air-fuel mixture at predetermined ignition timing so that unburned air-fuel mixture combusts by autoignition after start of combustion of the air-fuel mixture by the ignition, and the controller adjusts a heat amount ratio in accordance with an operation state of the engine through change of the ignition timing, the heat amount ratio representing an index associated with a ratio of an amount of heat generated when the air-fuel mixture combusts by flame propagation with respect to a total amount of heat generated when the air-fuel mixture combusts in the combustion chamber.