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.

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.

The invention provides a system and method for controlling corona discharge and arc formations during a single corona event, i.e. intra-event control. A driver circuit provides energy to the corona igniter and detects any arc formation. In response to each arc formation, the energy provided to the corona igniter is shut off for short time. The driver circuit also obtains information about the arc formations, such as timing of the first arc formation and number of occurrences. A control unit then adjusts the energy provided to the corona igniter after the shut off time and during the same corona event based on the information about the arc formations. For example, the voltage level could be reduced or the shut-off time could be increased to limit arc formations and increase the size of the corona discharge during the same corona event.

The invention provides a system and method for controlling corona discharge and arc formations during a single corona event, i.e. intra-event control. A driver circuit provides energy to the corona igniter and detects any arc formation. In response to each arc formation, the energy provided to the corona igniter is shut off for short time. The driver circuit also obtains information about the arc formations, such as timing of the first arc formation and number of occurrences. A control unit then adjusts the energy provided to the corona igniter after the shut off time and during the same corona event based on the information about the arc formations. For example, the voltage level could be reduced or the shut-off time could be increased to limit arc formations and increase the size of the corona discharge during the same corona event.

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 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.

A laser ignition device for an internal combustion engine can include a laser generator, a housing, and a window. The laser generator can emit a pulse of laser light. The housing can be coupled to the internal combustion engine. The housing can have a first end and a second end. The second end can be proximate to a combustion chamber of the internal combustion engine and can define an aperture through which the laser light is permitted to exit the housing into the combustion chamber. The window can be coupled to the second end of the housing and cover the aperture. The window can permit the laser light to pass through the window and into the combustion chamber. The window can have a rounded outer surface.

A laser ignition device for an internal combustion engine can include a laser generator, a housing, and a window. The laser generator can emit a pulse of laser light. The housing can be coupled to the internal combustion engine. The housing can have a first end and a second end. The second end can be proximate to a combustion chamber of the internal combustion engine and can define an aperture through which the laser light is permitted to exit the housing into the combustion chamber. The window can be coupled to the second end of the housing and cover the aperture. The window can permit the laser light to pass through the window and into the combustion chamber. The window can have a rounded outer surface.

A method for operating an internal combustion engine having a plurality of cylinders includes: measuring, by exhaust gas sensors arranged at an exhaust gas of every cylinder for which cylinder-specific combustion control is carried out, for each respective cylinder, at least one actual combustion value; comparing each respective measured actual combustion value with a reference combustion value to determine at least one cylinder-specific control deviation for every cylinder for which cylinder-specific combustion control is carried out; determining at least one cylinder-specific control variable for every cylinder for which cylinder-specific combustion control is carried out based on the cylinder-specific control deviation or on every cylinder-specific control deviation; and operating each cylinder for which cylinder-specific combustion control is carried out based on the respective cylinder-specific control variable to bring the respective actual combustion value closer to the respective reference combustion value and minimize the respective control deviation.

A method for operating an internal combustion engine having a plurality of cylinders includes: measuring, by exhaust gas sensors arranged at an exhaust gas of every cylinder for which cylinder-specific combustion control is carried out, for each respective cylinder, at least one actual combustion value; comparing each respective measured actual combustion value with a reference combustion value to determine at least one cylinder-specific control deviation for every cylinder for which cylinder-specific combustion control is carried out; determining at least one cylinder-specific control variable for every cylinder for which cylinder-specific combustion control is carried out based on the cylinder-specific control deviation or on every cylinder-specific control deviation; and operating each cylinder for which cylinder-specific combustion control is carried out based on the respective cylinder-specific control variable to bring the respective actual combustion value closer to the respective reference combustion value and minimize the respective control deviation.