A linear electro-mechanical system comprising: a stator including at least first and second stator electronic circuits or groups of circuits; a free piston mover movable in a reciprocating motion relative to the stator, the free piston including: a piston surface; a translator configured so that an electromagnetic force may be applied on the free piston mover by one or more of the stator electronic circuits or groups of circuits; and one or more translator electronic circuits, the system further comprising a switching device for each of the first and second stator electronic circuits or groups of circuits such that the current in each of the first and second stator electronic circuits or groups of circuits is independently controllable, and wherein at least one of the translator electronic circuits is configured to receive power from at least one of the independently controlled stator electronic circuits or groups of circuits during at least part of the stroke of the free piston mover.

A method of controlling an engine is provided, which includes the steps of injecting main fuel by a fuel injector during an intake stroke or a compression stroke, providing a mixture gas containing fuel and air inside a cylinder, applying by an ignition device a high voltage between electrodes of a spark plug at a timing when the mixture gas is not ignited, detecting a parameter related to a current value of an electric-discharge channel generated between the electrodes, determining by a controller whether the detected parameter is within a range between a first threshold and a second threshold to determine a flowing state of a vortex inside the cylinder, operating the spark plug to carry out a supplemental ignition when the parameter is determined to be outside the range, and igniting the mixture gas by operation of the spark plug after the supplemental ignition.

A method of controlling an engine is provided, which includes the steps of injecting main fuel by a fuel injector during an intake stroke or a compression stroke, providing a mixture gas containing fuel and air inside a cylinder, applying by an ignition device a high voltage between electrodes of a spark plug at a timing when the mixture gas is not ignited, detecting a parameter related to a current value of an electric-discharge channel generated between the electrodes, determining by a controller whether the detected parameter is within a range between a first threshold and a second threshold to determine a flowing state of a vortex inside the cylinder, operating the spark plug to carry out a supplemental ignition when the parameter is determined to be outside the range, and igniting the mixture gas by operation of the spark plug after the supplemental ignition.

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.

In at least some implementations, a method of operating an ignition system for a combustion engine includes charging an energy storage device during at least a portion of the time when the engine is operating, permitting the level of energy stored on the charge storage device to decrease over time after the engine ceases to operate, determining the energy level on the energy storage device when the engine is restarted after having ceased operating, and setting at least one engine operational parameter as a function of the determined energy level. In at least some implementations, the at least one engine operational parameter may include one or more of: richness of a fuel and air mixture to be delivered to the engine, ignition timing, desired engine idle speed.

In at least some implementations, a method of operating an ignition system for a combustion engine includes charging an energy storage device during at least a portion of the time when the engine is operating, permitting the level of energy stored on the charge storage device to decrease over time after the engine ceases to operate, determining the energy level on the energy storage device when the engine is restarted after having ceased operating, and setting at least one engine operational parameter as a function of the determined energy level. In at least some implementations, the at least one engine operational parameter may include one or more of: richness of a fuel and air mixture to be delivered to the engine, ignition timing, desired engine idle speed.

A control system and method for a multi-fuel generator engine are mainly applied to multi-fuel generator products. The control system comprises a controller, a first signal input terminal, a second signal input terminal, a third signal input terminal, and an output terminal connected to an ignition device of a generator engine. When the third signal input terminal of the controller receives a generator engine start signal and either the first signal input terminal or the second signal input terminal receives a signal corresponding to an on state of the corresponding valve assembly, the controller controls the ignition device to ignite. According to control system and method, the controller detects signals corresponding to the states of the two fuel valve assemblies to determine whether or not fuels are normally supplied, so that operating instabilities or faults caused by synchronous supply of two fuels to the generator engine are avoided.

A control system and method for a multi-fuel generator engine are mainly applied to multi-fuel generator products. The control system comprises a controller, a first signal input terminal, a second signal input terminal, a third signal input terminal, and an output terminal connected to an ignition device of a generator engine. When the third signal input terminal of the controller receives a generator engine start signal and either the first signal input terminal or the second signal input terminal receives a signal corresponding to an on state of the corresponding valve assembly, the controller controls the ignition device to ignite. According to control system and method, the controller detects signals corresponding to the states of the two fuel valve assemblies to determine whether or not fuels are normally supplied, so that operating instabilities or faults caused by synchronous supply of two fuels to the generator engine are avoided.

In at least some implementations, a method of operating an ignition system for a combustion engine includes charging an energy storage device during at least a portion of the time when the engine is operating, permitting the level of energy stored on the charge storage device to decrease over time after the engine ceases to operate, determining the energy level on the energy storage device when the engine is restarted after having ceased operating, and setting at least one engine operational parameter as a function of the determined energy level. In at least some implementations, the at least one engine operational parameter may include one or more of: richness of a fuel and air mixture to be delivered to the engine, ignition timing, desired engine idle speed.

In at least some implementations, a method of operating an ignition system for a combustion engine includes charging an energy storage device during at least a portion of the time when the engine is operating, permitting the level of energy stored on the charge storage device to decrease over time after the engine ceases to operate, determining the energy level on the energy storage device when the engine is restarted after having ceased operating, and setting at least one engine operational parameter as a function of the determined energy level. In at least some implementations, the at least one engine operational parameter may include one or more of: richness of a fuel and air mixture to be delivered to the engine, ignition timing, desired engine idle speed.