A direct injection engine includes a fuel injection valve configured to inject fuel into a cylinder, a water injection valve configured to inject water into the cylinder, and a valve variable mechanism configured to change an operation timing of each of an intake valve and an exhaust valve. During an operation in a low load range, a negative overlap period when both of the intake valve and the exhaust valve are closed across an exhaust top dead center is formed by the valve variable mechanism, and fuel is injected from the fuel injection valve and water is injected from the water injection valve respectively during the negative overlap period. This causes a steam reforming reaction such that at least a part of injected fuel and injected water turns to hydrogen and carbon monoxide within the cylinder during the negative overlap period.

This control apparatus for an engine includes an engine, an injector, a spark plug, an intake electric S-VT, an exhaust electric S-VT, and a controller. The controller outputs a control signal to at least one of the intake electric S-VT and the exhaust electric S-VT so as to perform valve control of opening an intake valve when an exhaust valve is open, and then outputs a control signal to the spark plug at predetermined ignition timing such that, after air-fuel mixture is ignited and combustion is started, unburned air-fuel mixture is combusted by autoignition.

A control system of a compression-ignition engine is provided, which includes an engine, an injector, a spark plug, and a controller connected to the injector and the spark plug, and configured to operate the engine by outputting a control signal to the injector and the spark plug. After the spark plug ignites mixture gas to start combustion, unburned mixture gas combusts by self-ignition. The controller outputs the control signal to the injector to perform a first-stage injection of fuel and then a second-stage injection in which fuel is injected to at least form the mixture gas around the spark plug. The controller also outputs the control signal to the injector to control a ratio of the injection amount of the second-stage injection with respect to the injection amount of the first-stage injection to be higher at a high engine speed than at a low engine speed.

An internal combustion engine includes a fuel injection system including a fuel injector disposed to inject fuel into the combustion chamber, and a plasma ignition system including a groundless barrier discharge plasma igniter that protrudes into the combustion chamber. A controller includes an executable instruction set to control the engine in a compression-ignition mode when the output torque request indicates a low load condition, including instructions to control a variable valve actuation system and control the plasma ignition system to execute plasma discharge events subsequent to controlling the fuel injection system to execute a fuel injection event, wherein the fuel injection event achieves a cylinder charge having a lean air/fuel ratio.

Provided is a control device for an internal combustion engine. The internal combustion engine includes cylinders, intake ports, exhaust ports, intake values, exhaust valves, fuel injection valves, and an exhaust valve stop mechanism. The control device includes an electronic control unit configured to control the fuel injection valves so as to inject the feel into the some cylinders at least during a period of time of a compression stroke or an expansion stroke of the some cylinders, control the exhaust valve stop mechanism so as to stop the exhaust valves of the exhaust ports of the some cylinders in a valve-closed state, and control the intake valves so as to open the intake valves at least during a period of time of an intake stroke of the some cylinders such that exhaust gas is recirculated to each of the cylinders via the intake ports of the some cylinders.

A method for controlling a valve arrangement for an internal combustion engine, the valve arrangement including a piston arrangement comprising a piston having a piston end portion facing an inlet valve of the valve arrangement. The method includes receiving a signal indicative of a temperature level of an exhaust gas after treatment system and when the signal indicates a temperature level below a predetermined threshold level: advancing an exhaust event of the internal combustion engine; and controlling the piston arrangement for reducing the distance between the piston end portion and the inlet valve before the internal combustion engine assumes an air intake event.

The present invention relates to a method for controlling a compression-ignition internal combustion engine, having at least one combustion chamber, wherein intake of air to said combustion chamber is controlled using an intake valve, and evacuation of said combustion chamber is controlled using an exhaust valve. The method comprises: controlling opening of said intake valve and closing of said exhaust valve in dependence of the position of a reciprocating member in said combustion chamber, wherein opening of said intake valve and closing of said exhaust valve, respectively, in relation to the position of said reciprocating member is individually controllable, and controlling opening and closing in relation to the position of said reciprocating member on the basis of a first control parameter, wherein said opening and closing of said intake valve and exhaust valve, respectively, are controlled such that an actual value of said control parameter is adjusted towards a desired value.

Torque fluctuations caused by misfire and abnormal combustion are prevented appropriately at the time of switching from SI to HCCI, and exhaust of NOx is restricted at the time of switching.

Provided is a control apparatus for an internal combustion engine performing a plurality of combustion modes each having a different air-fuel ratio and compression end temperature in a cylinder 7 from each other. In the middle of switching from a first combustion mode to a second combustion mode, an intermediate combustion mode in which the compression end temperature is increased while keeping a different air-fuel ratio from the air-fuel ratio of the first combustion mode and the air-fuel ratio of the second combustion mode is performed. Accordingly, at the time of switching between an operation mode performing SI and an operation mode performing HCCI, a temperature in the cylinder 7 and an air-fuel ratio are controlled appropriately, torque fluctuations caused by misfire and abnormal combustion can be prevented appropriately, and exhaust of NOx can be restricted.

Various embodiments may include a method for controlling the residual gas mass remaining in a cylinder of an internal combustion engine after a gas exchange process and/or the purge air mass introduced into an exhaust manifold during a gas exchange process, the method comprising: specifying at least one of a desired residual gas mass or a purge air mass of the cylinder of the internal combustion engine; determining a setpoint position of an actuator which influences the specified mass, based on an inverse residual gas model; and setting the determined setpoint position of the actuator.

An object of the present invention is to predict change of a combustion limit due to cycle variation of temperature and an EGR ratio and perform correction every cycle to decrease an amount of combustion consumption. Therefore, in an internal combustion engine control device that controls an internal combustion engine including a cylinder and an exhaust pipe, the internal combustion engine control device includes a control unit configured to perform EGR control of controlling an exhaust gas in the exhaust pipe to return to an inner cylinder of the cylinder, obtain temperature of the gas in the internal cylinder and an EGR ratio in a state where both an intake valve and an exhaust valve are closed in an combustion cycle, and correct a combustion parameter in a same combustion cycle as the combustion cycle on the basis of the obtained gas temperature and the obtained EGR ratio.