In an apparatus for controlling an air/fuel ratio of a general-purpose internal combustion engine using mixed fuel containing alcohol and gasoline and operated at a desired engine speed inputted by the operator while a throttle opening is regulated such that a detected engine speed converges to the inputted desired engine speed, a fuel injection amount determined for mixed fuel based on fuel injection amount characteristics is increased/decreased when a load is kept constant and the output air/fuel ratio is estimated to correct the fuel injection amount by the estimated air/fuel ratio, while a switch (knob) is installed to be manipulated by the operator to switch the fuel injection amount characteristics.

Provided is a dual-fuel engine control system including: a sensing unit for generating sensing information by sensing a parameter related to a dual-fuel engine; a main control unit for generating a control signal for controlling a micro-pilot injection value and a gas fuel inlet valve by analyzing a state of the dual-fuel engine on the basis of the sensing information; an EFI control unit for controlling the micro-pilot injection value and the gas fuel inlet valve on the basis of the control signal; and a deep learning unit for analyzing a state of the dual-fuel engine on the basis of the control signal transferred from the main control unit and the sensing information transferred to the main control unit at a time point of generating the control signal, and transferring an analysis result to the main control unit and the EFI control unit.

A method for starting an engine is provided. The method comprises in response to an engine start request, cycling a gaseous fuel injector prior to activating a starter motor. In this way, delayed engine starts using gaseous fuel may be mitigated.

Provided is a dual-fuel engine control system including: a sensing unit for generating sensing information by sensing a parameter related to a dual-fuel engine; a main control unit for generating a control signal for controlling a micro-pilot injection value and a gas fuel inlet valve by analyzing a state of the dual-fuel engine on the basis of the sensing information; an EFI control unit for controlling the micro-pilot injection value and the gas fuel inlet valve on the basis of the control signal; and a deep learning unit for analyzing a state of the dual-fuel engine on the basis of the control signal transferred from the main control unit and the sensing information transferred to the main control unit at a time point of generating the control signal, and transferring an analysis result to the main control unit and the EFI control unit.

An engine device (21) including: an intake manifold (67) configured to supply air into a cylinder (77); an exhaust manifold (44) configured to output exhaust gas from the cylinder (77); a gas injector (98) which mixes a gaseous fuel with the air supplied from the intake manifold 67; and a main fuel injection valve (79) configured to inject a liquid fuel into the cylinder (77) for combustion. At the time of switching the operation mode from one to the other between a gas mode and a diesel mode, an instant switching to the diesel mode is executed when the engine rotation number is determined to approach the upper limit value which leads to an emergency stop of the engine device.

Operating an engine system includes autoigniting a first fuel including a plurality of liquid fuels premixed with air, to trigger ignition of a direct-injected main fuel in a first engine cycle, and receiving data indicative of an undesired heat release of combustion of the first fuel. The undesired heat release may include an undesired heat release rate (HRR) modality such as a multistage combustion. Relative amounts of the plurality of the liquid fuels are varied and admitted to the cylinder in a second engine cycle, and the first fuel having the varied relative amounts autoignited to trigger ignition of the direct-injected main fuel in the second engine cycle. The undesired heat release can be limited in the second engine cycle based on the varied relative amounts of the liquid fuels. The first fuel may include a blend of dimethyl ether (DME), methanol (MeOH), and water. The direct-injected main fuel may include MeOH and water. Related apparatus and control logic is also disclosed.

A Dual-fuel combustion engine, possessing: a control device at least one combustion chamber at least one gas supply device for supplying a gaseous fuel to at least one combustion chamber, and at least one injector for injecting liquid fuel into the at least one combustion chamber, and which injector is controllable through a control device by the use of an actuator triggering signal, for which at least one injector possesses an output opening for the liquid fuel, which is closable by means of a needle (6), and for which the control device regulates through the use of the actuator triggering signal, the opening of the needle (6) in the ballistic region of the needle in a pilot operating mode of the combustion engine
to which end, an algorithm is stored in the control device, which receives, as input values, at least the actuator triggering signal (t) and, using an injector model, calculates the mass of liquid fuel introduced via the output opening of the injector, and which compares the mass calculated by means of the injector model with a required target value (m.sub.d.sup.ref) of the mass of liquid fuel, and on the basis of the result of such comparison, either leaves the actuator triggering signal (t) unchanged or corrects it, and a process for the operation of a combustion engine and of an injector.

A method is provided for operating an internal combustion piston engine, including introducing air into a cylinder of the engine, compressing the air in a first compression stroke of the cylinder, providing fuel into the cylinder for a first combustion, with a portion of the oxygen in the compressed air as oxidant, in a first power stroke succeeding the first compression stroke, to produce residues including oxygen, compressing the residues in a second compression stroke succeeding the first power stroke, and providing, after the first combustion, fuel into the cylinder for a second combustion, with at least a portion of the oxygen of the residues as oxidant, in a second power stroke succeeding the second compression stroke, wherein the first compression stroke is repealed immediately after the second power stroke, and the introduction of air into the cylinder is done at the end of the second power stroke and/or at the beginning of the first compression stroke.

A dual fuel engine system, such as for diesel and natural gas operation, includes a control system having an electronic control unit structured to vary a stored control valve for a fuel delivery parameter, responsive to engine power output. The engine power output can be determined by in-cylinder pressure monitoring during a liquid fuel mode. The stored control value can be a dynamically updated value in an engine fueling map.

A method includes receiving a plurality of signals from a plurality of sensors coupled to a dual fuel engine. The method further includes altering an actual speed of the dual fuel engine to obtain a predetermined air-fuel ratio in response to a changed operating condition of the dual fuel engine determined based on the plurality of signals, so as to maintain operation of the dual fuel engine between knock and misfire conditions.