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.

Systems, apparatuses, and methods of controlling an ignitor are disclosed. A method includes: receiving, by a controller, fuel quality data regarding a fuel for a spark-ignition engine; determining, by the controller, a fuel quality metric based on the fuel quality data; and controlling, by the controller, an ignition energy characteristic of an ignitor in response to the fuel quality metric.

Systems, apparatuses, and methods of controlling an ignitor are disclosed. A method includes: receiving, by a controller, fuel quality data regarding a fuel for a spark-ignition engine; determining, by the controller, a fuel quality metric based on the fuel quality data; and controlling, by the controller, an ignition energy characteristic of an ignitor in response to the fuel quality metric.

A multi-ignition coil control system includes a spark plug including first and second center electrodes, and first and second ground electrodes spaced apart from the center electrodes by a predetermined distance, a first ignition coil including a primary coil, and a secondary coil in which a discharge current is generated by electromagnetic induction with the primary coil, and a second ignition coil including a primary coil, and a secondary coil in which a discharge current is generated by electromagnetic induction with the primary coil, wherein one end of the secondary coil of the first ignition coil and one end of the secondary coil of the second ignition coil are electrically connected to one of the center electrodes, and the other end of the secondary coil of the first ignition coil and the other end of the secondary coil of the second ignition coil are electrically connected to the other of the center electrodes.

A multi-ignition coil control system includes a spark plug including first and second center electrodes, and first and second ground electrodes spaced apart from the center electrodes by a predetermined distance, a first ignition coil including a primary coil, and a secondary coil in which a discharge current is generated by electromagnetic induction with the primary coil, and a second ignition coil including a primary coil, and a secondary coil in which a discharge current is generated by electromagnetic induction with the primary coil, wherein one end of the secondary coil of the first ignition coil and one end of the secondary coil of the second ignition coil are electrically connected to one of the center electrodes, and the other end of the secondary coil of the first ignition coil and the other end of the secondary coil of the second ignition coil are electrically connected to the other of the center electrodes.

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.

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 device for an internal combustion engine includes a switching circuit and a control circuit. The control circuit monitors a voltage level inputted to a switching device which is installed in the switching circuit and connected to a primary winding of an ignition coil. The control circuit includes an overvoltage protection circuit which outputs an energization inhibit signal to inhibit energization of the switching device when the monitored voltage level is higher than an overvoltage threshold level. When the monitored voltage level exceeds the overvoltage threshold level in an output duration in which the energization control signal is outputted, the overvoltage protection circuit stops output of the energization inhibit signal until the output duration expires. This enables the switching device to be protected from damage and an ignition operation to be executed at a correct timing to eliminate a risk of damage to the internal combustion engine.

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 apparatus for an internal combustion engine includes: a spark plug; a first ignition coil and a second ignition coil; a battery; a booster circuit that boosts a voltage supplied from the battery; a power transistor that conducts and interrupts a primary current flowing to a primary coil included in the first ignition coil; a MOSFET that applies and interrupts the voltage boosted by the booster circuit to a primary coil included in the second ignition coil; and an ECU that starts electric discharge by the spark plug by controlling the power transistor, and repeatedly applies and interrupts the voltage boosted by the booster circuit by the MOSFET so that the electric discharge that is started is maintained.