A method and system for perform a charge exchange in internal combustion engine comprising an additional intake and exhaust valve lifts performed during positive pressure gradients between the intake and exhaust systems to reducing scavenging losses and increase torque during low engine speeds.

Aspects of the present invention relate to a controller for controlling operation of an internal combustion engine, a control system, an internal combustion engine, a vehicle, a method and a non-transitory computer readable medium. The controller is configured to, during fuel cut, cause opening of an intake valve of a cylinder of the internal combustion engine to enable air having a mass to enter the cylinder. The mass is below a first range of masses which enable the internal combustion engine to provide combustion torque.

Methods and systems are provided for synergizing the benefits of a variable compression ratio engine in a hybrid vehicle system. A vehicle controller may hold the engine in a lower compression ratio during engine pull-ups and pull-downs, in particular when passing through a low speed region where compression bobbles can occur. During engine operation, in response to a change in driver demand, the controller may opt to switch the compression ratio or maintain a current compression ratio while smoothing a torque deficit using motor torque, the selection based on fuel economy.

A method for operating a compression ignition engine includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into the at least one cylinder, compressing the combustible mixture with the piston in a compression stroke, injecting a second fuel to the combustible mixture at an injection-time of the second fuel during the compression stroke but before start of combustion, and continuing the compression stroke until combustion starts at those locations in the at least one cylinder where concentration of the second fuel is highest and/or the temperature of the mixture is the highest. Emission of the cylinder and/or mechanical stress of the cylinder caused by the combustion are monitored, and if emissions and/or mechanical stress are above respective predetermined thresholds, individually for the cylinder, the amount and/or the timing of the second fuel injected, and/or temperature of the cylinder charge is changed.

A controller for controlling an internal combustion engine includes a valve timing adjuster, a variable valve lift mechanism and a processor. The processor controls a duty cycle of a drive signal in a selected one of control modes, thereby changing a relative rotational phase of a camshaft relative to an engine output shaft. The control modes include a specific control mode in which the duty cycle of the drive signal is adjusted to change a value of the current through a first motor. The processor performs, when changing the relative rotational phase through execution of the specific control mode, an abnormality diagnosis for the variable valve lift mechanism based on a comparison between the current value at the first motor and a reference current value. The processor sets the reference current value in accordance with a rotation angle of the output shaft of a second motor.

Methods and systems are provided for a hydrogen combustion engine. In one example, a method may include operating the hydrogen combustion engine at one of two combustion air ratios, wherein a combustion air ratio between the two is avoided via adjusting one or more operating parameters.

A variable valve operating system assembled in an engine includes a first rocker arm contacting with a valve, a second rocker arm no contacting with any valve, a lost motion spring bringing the second rocker arm into contact with a cam, and switching device for switching the first/second rocker arms to a coupled or uncoupled state. An operation control apparatus for the engine includes element for determining whether or not an engine speed is higher than a first speed at which supply of fuel is allowed to be temporarily stopped, and element for setting a requested quantity of increase/decrease in internal resistance of the engine. When the engine speed is higher than the first speed and an accelerator opening degree is 0%, the switching device switches the first/second rocker arms to the coupled or uncoupled state based on the requested quantity.

The disclosure relates to a method for controlling an internal combustion engine. The internal combustion engine includes a cylinder and a piston, which runs in the cylinder, together delimiting a working chamber. The working chamber is supplied with fresh air from an intake section via an inlet valve and is connected to an exhaust manifold via exhaust valves. The internal combustion engine includes a variable valve actuation system for the actuation of the inlet valves, controlling the opening time and/or the closing time and/or the lift. A strategy for shutting down the internal combustion engine includes controlling the inlet valves of individual or all working chambers in such a way that the transfer of fresh air from the intake section to the exhaust manifold is reduced or avoided and that the drag torque of the intake combustion engine is reduced.

The invention relates to a method of controlling a variable valve timing arrangement of an internal combustion engine, the variable valve timing arrangement being arranged to control the timing of an intake valve and an exhaust valve of the internal combustion engine, the method comprising: controlling the variable valve timing arrangement so as to delay the intake valve lifts and to advance the exhaust valve lifts in response to at least one parameter representative of a current load of the internal combustion engine passing a certain threshold value, thereby indicating that the internal combustion engine is operated in a low load state The invention relates also to a computer program product comprising program code for a computer for implementing a method according to the invention. The invention relates also to a control arrangement and a vehicle comprising the control arrangement.

An engine control apparatus includes an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate the SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes the injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Energy of the preceding ignition is set to be higher when an engine speed is high than when the engine speed is low.