A spark plug heat up method via transient control of the spark discharge current. The high temperature plasma channel is used to heat up the central electrode, and the temperature and energy of the plasma channel are realized via transient control of the discharge current. The heating up process takes place before firing the engine, using discharge current to actively heat up the spark plug from inside. By monitoring the discharge current amplitude and discharge duration, the temperature change of the central electrode and the ceramic insulator can be carefully measured and controlled within a proper window. This method can be used to measure the heating range of the spark plug, and to prevent or remove the carbon deposit on the central electrode and the ceramic insulator generated under various engine operation conditions, such as engine cold start, full load operation, and heavy EGR condition, as well as realize self-cleaning.

It is disclosed an electronic device to control an ignition coil of an internal combustion engine, comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor. The integrating capacitor is configured, in the case wherein a pre-ignition of the comburent-combustible mixture in the combustion chamber during the phase of charging occurs, to pre-charge during the phase of charging energy in the primary winding and it is configured, in the case wherein the pre-ignition of the comburent-combustible mixture does not occur, to maintain the charge state substantially constant during the phase of charging energy.

A hybrid vehicle includes an internal combustion engine, a rotating electric machine, an electric storage device, a power supply device, and a controller. The controller executes switching control to switch from a first electric power supply to a second electric power supply by starting the internal combustion engine. The first electric power supply is the supply of electric power from the electric storage device to the electric device. The second electric power supply is the supply of electric power from the rotating electric machine to the electric device. The controller controls the power supply device and the internal combustion engine such that the internal combustion engine is started with the first electric power supply being continued during the switching control.

An ignition control device includes a control unit to control first to third switching elements so that during ignition discharge, which is started by turning off the first switching element, energy stored on a capacitor is discharged by turning off the third switching element and turning on the second switching element for supplying a primary current to an end of a primary winding opposite to an end thereof connected to a direct-current power supply. During inductive discharge of a spark plug, the control unit non-intermittently turns on the second switching element so that the second switching element is turned on over a successive energy input time period, according to the operating conditions of an internal combustion engine.

It is possible to adjust electromagnetic energy introduced from a low-voltage side of a primary winding 20 of an ignition coil 2 after start discharging to a spark plug 1 from the ignition coil 2 in the correct proportion by threshold-determining either one or both of a primary voltage V1 applied to a primary side of the ignition coil 2 and a secondary current I2 flowing in a secondary side of the ignition coil 2, and by opening and closing a discharging switch 32 disposed between an auxiliary power supply 3 including an energy storage coil 330 and a low-voltage side terminal 201 of the ignition coil 2.

It is possible to adjust electromagnetic energy introduced from a low-voltage side of a primary winding 20 of an ignition coil 2 after start discharging to a spark plug 1 from the ignition coil 2 in the correct proportion by threshold-determining either one or both of a primary voltage V1 applied to a primary side of the ignition coil 2 and a secondary current I2 flowing in a secondary side of the ignition coil 2, and by opening and closing a discharging switch 32 disposed between an auxiliary power supply 3 including an energy storage coil 330 and a low-voltage side terminal 201 of the ignition coil 2.

An ignition apparatus includes a spark plug having a high voltage electrode and an external electrode facing each other across a gap and being configured to generate a spark discharge in the gap to ignite a combustible fuel mixture in a combustion chamber of an internal combustion engine, an ignition coil device configured to generate a predetermined high voltage and supply the high voltage to the high voltage electrode to form a path for the spark discharge in the gap, a high frequency power supply having a band-pass filter and being configured to supply an alternating current to the spark discharge path, and a control device configured to control operation timing of the high frequency power supply. The band-pass filter passes a frequency of from 1 MHz to 4 MHz.

It is disclosed an electronic device to control an ignition coil of an internal combustion engine comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor. The integrating capacitor is configured, in the case wherein a pre-ignition of the comburent-combustible mixture in the combustion chamber during the phase of charging occurs, to pre-charge during the phase of charging energy in the primary winding and it is configured, in the case wherein the pre-ignition of the comburent-combustible mixture does not occur, to maintain the charge state substantially constant during the phase of charging energy.

A spark plug heat up method via transient control of the spark discharge current. The high temperature plasma channel is used to heat up the central electrode, and the temperature and energy of the plasma channel are realized via transient control of the discharge current. The heating up process takes place before firing the engine, using discharge current to actively heat up the spark plug from inside. By monitoring the discharge current amplitude and discharge duration, the temperature change of the central electrode and the ceramic insulator can be carefully measured and controlled within a proper window. This method can be used to measure the heating range of the spark plug, and to prevent or remove the carbon deposit on the central electrode and the ceramic insulator generated under various engine operation conditions, such as engine cold start, full load operation, and heavy EGR condition, as well as realize self-cleaning.

An engine ignition system can include a multifunction controller, and an exciter operatively connected to the multifunction controller. The multifunction controller can be configured to control the exciter to output an ignition voltage. The multifunction controller can be configured to perform at least one other engine control function.