To alleviate or eliminate a problem of unburned fuel discharged to the outside of a cylinder in a case in which an air fuel mixture is insufficiently combusted in a combustion chamber. During the expansion stroke in which a high voltage is applied to an ignition plug via an ignition coil, and a spark discharge is caused to occur at the ignition plug, thereby the air fuel mixture in the combustion chamber is ignited and combusted, in a case in which deterioration of combustion state is detected, a microwave electric field is created in the combustion chamber prior to an opening timing of an exhaust valve at an end stage of the expansion stroke, thereby plasma is generated and enlarged in the combustion chamber.

Methods and systems are provided for reducing torque transients experienced when a dedicated EGR cylinder is deactivated to reduce EGR. Before deactivating the dedicated cylinder, an intake throttle position and spark timing of remaining engine cylinders is adjusted to build-up torque reserve in anticipation of a negative torque transient at deactivation. Then, the throttle position or spark timing is adjusted to reduce torque when a positive torque transient is expected.

The invention provides a system and method for controlling corona discharge. A driver circuit provides energy to the corona igniter and detects any arc formation. Optionally, in response to each arc formation, the energy provided to the corona igniter is shut off for a short time to dissipate the arc. Once the arc dissipates, the energy is applied again to restore the corona discharge. The driver circuit obtains information relating to the corona discharge, such as timing and number of arc formations. A control unit adjusts the energy provided to the corona igniter, shut-off time, or the duration of the corona event based on the information. The adjusted energy levels and duration are applied during subsequent corona events. For example, the voltage level could be reduced or the shutoff time could be increased to limit arc formations and increase the size of the corona discharge during the subsequent corona events.

An internal combustion engine includes a combustion chamber formed by cooperation of a cylinder bore formed in a cylinder block, a cylinder head and a piston. A combustion ignition device is disposed in the combustion chamber and includes a nozzle defining a pre-chamber, a barrier discharge plasma igniter, including a tip portion disposed in the pre-chamber and a plurality of apertures disposed in the nozzle. The pre-chamber is in fluidic communication with the combustion chamber via the plurality of apertures. A controller is in communication with the engine and the barrier discharge plasma igniter.

A method for operating a combustion engine after a cold start, the combustion engine including a supercharger device, a plurality of combustion chambers, a fuel-injection device injecting into each of the combustion chambers, and a gas-exchange valve control device that controls gas-exchange valves in a variable manner. A rich fuel-air mixture is generated in the combustion chambers, and the combustion-chamber charges are ignited in a retarded manner. Following the cold start, the combustion engine is operated with first valve overlaps that are greater than in a warm combustion engine. A first exhaust valve of a first combustion chamber is initially closed at such a late point that its opening duration overlaps with the opening duration of a second exhaust valve of a second combustion chamber that directly follows the first combustion chamber in the ignition sequence and that discharges into the same exhaust manifold as the first combustion chamber.

Methods and systems are provided for improving the detection and mitigation of high speed pre-ignition. In one example, high speed pre-ignition is detected based on concurrent or sequential changes in an integrated knock sensor output in a knock window as well as a pre-ignition window. The high speed pre-ignition is addressed using cylinder fuel deactivation and/or engine load limiting to reduce the risk for run-away pre-ignition.

A method and system for reducing cycle to cycle variation of an engine is provided. The system may determine fuel injection characteristics and predict a gas burning rate or flame speed based on the fuel injection characteristics. The system may adjust an ignition timing in response to the predicted gas burning rate within the same engine cycle.

An ECU outputs an ignition signal Si to an ignition apparatus through an ignition communication line, and outputs a discharge waveform control signal Sc with a logic H through a waveform control communication line. The ignition apparatus performs the closing operation of an ignition switching element, in a period during which the ignition signal Si is input. In an input period of the discharge waveform control signal Sc after stopping the input of the ignition signal Si, the ignition apparatus controls the electric current to flow through a primary coil, by the opening-closing operation of a control switching element. When the voltage of the waveform control communication line Lc is the logic H in an output stop period of the discharge waveform control signal Sc, the ECU determines that the waveform control communication line is abnormal, and executes a fail-safe process.

An ignition device for engine according to the present invention performs continuous spark discharge of an ignition plug by using a multiplex signal, an integration signal or a control signal. In the multiplex signal, discharge continuous signals IGW#1 to 4 for cylinders of the engine have been multiplexed. In the integration signal, a discharge continuous signal IGW and a secondary current instruction signal IGA have been added to an ignition signal IGT. In the control signal, the secondary current instruction signal IGA has been added into the multiplex signal or the integration signal. This structure can reduce the total number of signal lines connected between an ECU and a controller, and further reduce a signal line to transmit the secondary current instruction signal IGA.

An ignition device for engine according to the present invention performs continuous spark discharge of an ignition plug by using a multiplex signal, an integration signal or a control signal. In the multiplex signal, discharge continuous signals IGW#1 to 4 for cylinders of the engine have been multiplexed. In the integration signal, a discharge continuous signal IGW and a secondary current instruction signal IGA have been added to an ignition signal IGT. In the control signal, the secondary current instruction signal IGA has been added into the multiplex signal or the integration signal. This structure can reduce the total number of signal lines connected between an ECU and a controller, and further reduce a signal line to transmit the secondary current instruction signal IGA.