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 ignition coil control system includes: a plurality of ignition coils that respectively include a primary coil and a secondary coil; a spark plug that generates a spark discharge by a discharge current generated by the plurality of ignition coils and that includes a center electrode and a ground electrode; a sensing part measuring a current applied to the primary coil; and an ignition controller that adjusts a reference duty signal based on an amount of the current applied to the primary coil sensed by the sensing part to adjust discharge energy generated between the center electrode and the ground electrode through the secondary coil.

Failure in ignition of a fuel by an ignition plug is reduced, and, at the same time, wearing of electrodes of the ignition plug in an internal combustion engine is suppressed. A control device 1 for an internal combustion engine includes an ignition control unit that controls energization of an ignition coil 300 that supplies electric energy to an ignition plug 200 that discharges in a cylinder 150 of the internal combustion engine 100 to ignite fuel. The ignition control unit controls the energization of the ignition coil 300 such that first electric energy is released from the ignition coil 300 and second electric energy is released in superposition with the first electric energy. At this time, the energization of the ignition coil 300 is controlled such that releasing of the second electric energy is stopped at a timing that depends on a state of gas around the ignition plug 200 so that the discharge of the ignition plug 200 is stopped.

An ignition coil control system includes a spark plug that generates a spark discharge between a center electrode and a ground electrode and two ignition coils that respectively apply a current to the spark plug. The two ignition coils respectively include a primary coil, a secondary coil, and a main switch that selectively connects the primary coil. An auxiliary switch may be connected in parallel to each of the primary coils.

Disclosed is an ignition drive module with stable performance and reliable function, which comprises a module signal input end, a voltage input end, a module signal output end, a comparator. One end of the comparator is connected to the module signal input end, and the other end is connected to a comparison resistance R that is grounded. The ignition drive module further comprises a maximum dwell timer module connected to the comparator, a logical judgment module connected to the comparator, and an IGBT module connected to the logical judgment module which receives the signals from the maximum dwell timer module and the comparator to determine whether to activate the IGBT module. The output end of the IGBT module is connected to the module signal output end.

When an operating condition including load and speed of an internal combustion engine is in a prescribed low-speed high-load region, i.e., an energy suppression region, having a possibility causing pre-ignition, energization time TDWLMIN for the energy suppression region is selected as a primary coil energization time. In other normal regions, normal energization time TDWL is selected. Normal energization time TDWL has a characteristic such that the normal energization time shortens, as the engine speed increases. In a low speed region, a given energization time that can fulfill a discharge energy required in a high exhaust gas recirculation region is provided. Energization time TDWLMIN for the energy suppression region is constant regardless of engine speeds and relatively short, and is set to a level such that a coil generated maximum voltage does not exceed a withstand voltage of a spark plug even when no-discharge occurs due to pre-ignition.

An ignition device includes a spark plug, a measurement value detector, an electrical breakdown determiner, an AC voltage applying section, and a first changing section. The measurement value detector includes primary and secondary coils, and detects at least one measurement value among an ignition coil, a primary current, a primary voltage, a secondary current, and a secondary voltage. The electrical breakdown determiner determines whether a discharge has become an electrical breakdown state based on the measurement value. The AC voltage applying section applies an AC voltage of a first predetermined frequency that causes voltage resonance to the primary coil. The first changing section changes the frequency of the AC voltage to a second predetermined frequency that can maintain the electrical breakdown state and is lower in frequency than the first predetermined frequency when it is determined that the discharge has become the electrical breakdown state.

An ignition coil system is configured for use with a spark ignition internal combustion engine. The system includes a first switching circuit electrically connected to the primary coil that provides electrical power to the primary coil. The system includes a second switching circuit connected to the primary coil that is configured to short the terminals of the primary coil after the secondary current has been induced in the secondary coil, whereby the secondary coil induces a current in the primary coil, thereby reducing the secondary current in the secondary wire coil. A controller in communication with the first and second switching circuits is configured to receive a single electronic spark timing (EST) signal and to control the conductive states and the non-conductive states of the first and second switching circuits based on this single EST signal.

To provide an ignition control device of an internal combustion engine capable of reducing the number of adjustment steps required for adjustment such as matching of a MOS gate voltage or the like without being affected by device variation. A detection voltage is generated on the basis of a primary current flowing through a current detection resistor having a positive temperature dependent characteristic. A reference voltage is generated by a potential difference between a base and an emitter of a first bipolar transistor circuit and a multiple type second bipolar transistor circuit in which a plurality of bipolar transistors are connected in parallel, and a resistance value of a first resistor connected to the emitter side of the plurality of the bipolar transistor circuit, on the basis of a current having a positive temperature dependent characteristic similar to the current detection resistor.

Provided is an ignition system including: a main primary coil; a sub primary coil; a secondary coil; a control unit configured to: drive a main IC to switch a main primary coil mode from a de-energization mode to an energization mode; stop the drive of the main IC to switch the main primary coil mode from the energization mode to the de-energization mode; drive the sub IC to switch a sub primary coil mode from a de-energization mode to an energization mode; and stop the drive of the sub IC to switch the sub primary coil mode from the energization mode to the de-energization mode; and a detection circuit configured to detect a state of the secondary coil. The ignition system is configured such that the drive of the sub IC is stopped when the state of the secondary coil detected by the detection circuit is a no-current supply state.