Ignition control system for internal combustion engine

An ignition control system for an internal combustion engine, the ignition control system comprising:

• an ignition apparatus including
• an ignition coil that is provided with a primary coil and a secondary coil,
• a spark plug that is connected with the secondary coil and that is exposed in a combustion chamber of the internal combustion engine,
• a discharge control circuit that continues discharge of the spark plug after a start of the discharge of the spark plug, and
• a discharge control unit that controls a discharge current of the spark plug by operating the discharge control circuit, after the start of the discharge of the spark plug;
• a control apparatus;
• an ignition communication line that transmits an ignition signal from the control apparatus to the ignition apparatus;
• and
• a waveform control communication line that transmits a discharge waveform control signal from the control apparatus to the ignition apparatus, wherein
• the ignition signal commands energization of the primary coil,
• the discharge waveform control signal commands a finish timing of the control of the discharge current by the discharge control unit, by an input stop timing to the ignition apparatus,
• the control apparatuses is configured to variably control a discharge current value by variably setting a delay time of an input timing of the discharge waveform control signal to the ignition apparatus relative to an input timing of the ignition signal to the ignition apparatus, the discharge current value being controlled by the discharge control unit depending on the delay time,
• the discharge control unit is configured to control the discharge current value so that the discharge current value increases as the delay time increases, and the discharge current value decreases as the delay time decreases, and
• the control apparatus is configured to control the delay time so that the delay time increases as a rotation speed of the internal combustion engine increases and the delay time decreases as the rotation speed of the internal combustion engine decreases.