An ignition coil control system may include first and second ignition coils, and a spark plug including a pair of electrodes in which generates spark discharge by discharge currents of the first ignition coil and the second ignition coil, a DC-DC converter connected to a primary coil of the first ignition coil, a primary coil of the second ignition coil and a battery; in which converts current magnitude supplied to a primary coil of the first ignition coil and a primary coil of the second ignition coil from a battery, and a controller in which controls the spark discharge of the electrodes by adjusting an amount and a duration of the discharge current of the first ignition coil and the second ignition coil base on a pulse signal, wherein the controller is configured to selectively execute a multi-state ignition through the first ignition coil and the second ignition coil and a single-stage ignition through one of the first ignition coil and the second ignition coil according to an operation region of an engine.

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.

Disclosed is a method for determining a need for changing a spark plug of a combustion engine, comprising the following steps: monitoring a current flowing through the spark plug, analyzing the current and thereby determine a time interval that is indicative for the time between application of a voltage to the spark plug and formation of an arc discharge between electrodes of the spark plug, creating a signal indicative of the need to change the spark plug if the duration of the determined time interval is outside predefined bounds.

An igniter that includes switch element and switch control device for controlling the switch element depending on ignition signal. The switch control device includes a determination stage that compares voltage associated with the ignition signal with a predetermined voltage to generate a determination signal, a driving stage that controls ON/OFF operations of the switch element depending on the determination signal, a timer circuit that asserts a conduction protection signal when state where the determination signal becomes an assert level corresponding to an ON operation of the switch element continues for predetermined time, a time-varying voltage generating circuit that generates time-varying voltage over time in response to the assertion of the conduction protection signal, and an amplifier that changes the voltage of a control terminal of the switch element such that detection voltage associated with coil current flowing in the switch element is close to the time-varying voltage.

An ignition control device for an internal combustion engine can include an ignition coil supplying a discharge voltage to an ignition device of an ignition combustion engine, a voltage-controlled type semiconductor element connected to a primary side of the ignition coil and an ignition control section capable of repeating, multiple time in an ignition period, operations of turning ON and turning OFF of the voltage-controlled type semiconductor element by giving a gate signal to a gate of the voltage-controlled type semiconductor element. The ignition control section can include an active element that discharges gate charges accumulated on the gate of the voltage-controlled type semiconductor element upon turning OFF operation of the voltage-controlled type semiconductor element to the ground, and that is connected between the gate and a resistor at a side of the gate inserted in a gate wiring connected to the gate of the voltage-controlled type semiconductor element.

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 control system performs discharge generation control, in which a discharge spark is generated, once or a plurality of times during a single combustion cycle. The ignition control system successively calculates an approximate energy density based on a secondary current and a discharge path length. During a predetermined period after blocking of a primary current is performed during a single combustion cycle, the ignition control system calculates an integrated value by integrating the discharge path length at this time, based on the approximate energy density being greater than a predetermined value. The ignition control system performs the discharge generation control again based on the calculated integrated value being less than a first threshold.

A current control circuit for an ignition system (i.e., igniter current limiter) is disclosed. The current control circuit can reduce a coil current over a soft shut down (SSD) period using an insulated gate bipolar transistor (IGBT) that is controlled by a negative feedback loop, which controls the current limit of the IGBT according to a SSD profile. In order to prevent an unwanted current rise during the soft shut down period, the current control circuit compares a gate voltage of the IGBT to a reference signal and based on the comparison can enable the SSD profile to include a fast ramp. The fast ramp quickly lowers the current limit of the IGBT so that the coil current equals the current limit and can be controlled by the negative feedback loop.

An ignition coil control system may include a first ignition coil including a primary coil and a secondary coil; a first switch that selectively electrically-connects the primary coil of the first ignition coil; a second ignition coil including a primary coil and a secondary coil; a second switch that selectively electrically-connects the primary coil of the second ignition coil; a pair of electrodes generating spark discharge by a discharge current generated in the first ignition coil and the second ignition coil; and an ignition controller that controls spark discharge of the pair of electrodes by adjusting an amount and a duration of the discharge current of the first ignition coil and the second ignition coil by turning the first switch and the second switch on or off according to a single pulse signal having a constant voltage including different voltages transmitted from an engine control unit (ECU).

An ignition coil control system may include a first ignition coil including a primary coil and a secondary coil; a first switch that selectively electrically-connects the primary coil of the first ignition coil; a second ignition coil including a primary coil and a secondary coil; a second switch that selectively electrically-connects the primary coil of the second ignition coil; a pair of electrodes generating spark discharge by a discharge current generated in the first ignition coil and the second ignition coil; and an ignition controller that controls spark discharge of the pair of electrodes by adjusting an amount and a duration of the discharge current of the first ignition coil and the second ignition coil by turning the first switch and the second switch on or off according to a single pulse signal having a constant voltage including different voltages transmitted from an engine control unit (ECU).