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.

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.

An ignition system includes a primary coil, a secondary coil, a first switch, a second switch, a third switch, a diode, and a switch control section. In the primary coil, a power supply is connected to a contact point between a first winding and a second winding. The secondary coil is magnetically coupled to the primary coil. The first switch is connected in series with the first winding. The second switch is connected in series with the second winding on the opposite side from the contact point. The third switch is connected in series with the second switch. The diode includes an anode connected between the second switch and the third switch and a cathode connected to the contact point. The switch control section controls opening and closing of each switch.

Methods and systems are provided for determining a type of spark plug fouling. In one example, a method may include differentiating spark plug fouling due to soot accumulation from spark plug fouling due to fuel additive accumulation based on a current on a control wire of the spark plug following application of a dwell command. Further, exhaust oxygen sensor degradation and/or exhaust catalyst degradation may be determined based on switching frequencies of one or more exhaust oxygen sensors and the type of spark plug fouling.

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.

A system and method for providing multiple commands to an ignition coil driver circuit to provide spark, ion signal integration, and ignition coil shunting during a cycle of a cylinder is presented. In one example, multiple voltage pulses are provided over a single conductor communication link. The voltage pulses provide encoded instructions for ignition timing, ignition coil shunting, and ion signal integration.

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.

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.

In an ignition control device for an internal-combustion engine, signal separation circuitry receives and separates an ignition control signal that is an integrated signal of a main ignition signal for controlling the main ignition operation, an energy input signal for controlling the energy input operation, and a target secondary current command signal. The ignition control signal is formed of a first signal and a second signal that are pulsed signals. The signal separation circuitry is configured to generate, from the ignition control signal, the main ignition signal based on rising edges of the first signal and the second signal as pulse-waveform information of the first signal and the second signal, generate the energy input signal based on a pulse width of the second signal as pulse-waveform information of the second signal, and generate the target secondary current command signal based on pulse-waveform information of the first signal.

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 connected to the module signal input end a maximum dwell timer module connected to the comparator, a logical judgment module connected to the comparator, and an insulated gate bipolar transistor connected to the logical judgment module. The logical judgment module receives signals from the maximum dwell timer module and the comparator to determine whether to activate the insulated gate bipolar transistor. The output end of the insulated gate bipolar transistor is connected to the module signal output end.