A combustion system is applied to an engine. The combustion system includes an injection device that injects a fuel into a combustion chamber, a spark plug that ignites fuel in the combustion chamber, and a control device that controls the injection device and the spark plug. The control device includes a first control unit that executes predetermined first control. In the first control, control is performed such that, a total injection amount corresponding to all the fuel injected by the injection device in one combustion cycle of the engine is injected within a first period corresponding to a period from valve close timing which brings an intake valve into a closed state until a first half of a compression stroke of the engine ends.

Methods and systems are provided for controlling a vehicle engine to reduce engine knock and increase fuel efficiency by reducing hydrocarbon breakthrough. In one example, a method may include adjusting a compression ratio of a variable compression engine in response to hydrocarbon breakthrough above a threshold from a fuel vapor canister of an evaporative emissions system.

An internal combustion engine control device includes an engine state estimation unit, a wall surface temperature estimation unit, and an operation amount calculation unit. The engine state estimation unit calculates the energy transfer amount from the gas to the wall surface based on the parameter related to the operating condition, the parameter related to the chemical condition of combustion, and the parameter related to an operation status. The wall surface temperature estimation unit estimates the wall surface temperature on the basis of the energy transfer amount from the gas to the wall surface. The operation amount calculation unit calculates an operation amount of an actuator provided in the internal combustion engine on the basis of the wall surface temperature estimated by the wall surface temperature estimation unit.

An internal combustion engine includes an internal combustion engine main body including a plurality of cylinders, a knock sensor provided on each of the plurality of cylinders, a control board including an amplification circuit, and a plurality of cables differing in length and each connecting the knock sensor and the control board. The amplification circuit includes, for each of the plurality of cables, a first charge amplifier connected to a first output terminal of the knock sensor via one of the plurality of cables, a second charge amplifier connected to a second output terminal of the knock sensor via one of the plurality of cables, and a differential amplifier configured to take an output of the first charge amplifier and an output of the second charge amplifier as input.

A normal control unit performs a normal control to cause an injection apparatus to perform predetermined normal injection and subsequently cause an ignition plug to perform ignition. In a delay region in a combustion chamber, propagation of flame is retarded further than in another region when the normal control is performed. In a knock state, self-ignition occurs in the delay region when the normal control is performed. When the knock state is established, an adjustment control unit performs, to suppress the self-ignition, an adjustment control to perform main injection and subsequently perform sub-injection in a second half of a compression stroke to adjust a fuel distribution in the combustion chamber to facilitate propagation of flame to the delay region further than in the normal control and subsequently cause the ignition plug to perform the ignition.

A knocking determination device detects a vibration generated in an internal combustion engine during a predetermined period in each combustion cycle of the internal combustion engine. The knocking determination device performs a knocking determination of a presence or absence of a knock based on a vibration waveform in a predetermined frequency band component of the vibration detected.

A system for training a deep learning system to detect engine knock with accuracy associated with high fidelity knock detection sensors despite using data from a low fidelity knock detection sensor. The system includes an engine, a high fidelity knock detection sensor, a low fidelity knock detection sensor, and an electronic processor. The electronic processor is configured to receive first data from the high fidelity knock detection sensor. The electronic processor is also configured to receive second data from the low fidelity knock detection sensor. The electronic processor is further configured to map the first data to the second data, train the deep learning system, using training data including the mapped data, to determine a predicted peak pressure using data from the low fidelity knock detection sensor, receive third data from the low fidelity knock detection sensor, and using the third data, determine the predicted peak pressure.

A system and method for self-adjusting engine performance parameters in response to fuel quality variations that includes an exhaust sensor for measuring a level of carbon dioxide present in an exhaust manifold, at least one of a knock sensor and a cylinder pressure transducer for determining a location of peak pressure and a centroid, respectively, a controller in communication with the exhaust sensor and the at least one of the knock sensor and the cylinder pressure transducer, the controller correlating a methane number of the fuel used by the engine to a brake specific carbon dioxide value calculated using the level of carbon dioxide measured by the exhaust sensor and the at least one of the centroid and the location of peak pressure, and an adjusting mechanism, wherein the adjusting mechanism adjusts an engine performance parameter based on the determined methane number.

A method for sensing damage of bearing of engine using a vibration signal may include separating a vibration signal of an engine sensed by a vibration sensor installed at one side of the engine of a vehicle into a vibration signal by combustion knocking and a vibration signal of a bearing installed between a crank pin and a connecting rod; extracting, by a signal processing filter, a signal of a predetermined natural frequency band from the vibration signal of the bearing; determining whether the vibration signal of the bearing is higher than a predetermined bearing damage threshold, in a predetermined engine state condition in order to sense breakage of the bearing during operation of the engine; and confirming that the bearing has been damaged.

A control system of an electronic-controlled oil-gas dual fuel engine includes electronic control pumps, fuel gas injection electromagnetic valves, a fuel gas control device and a fuel oil control device. The fuel gas control device and the fuel oil control device are electrically connected with a control device of the engine. The fuel gas control device is electrically connected with the fuel gas injection electromagnetic valves and controls the opening time and the opening duration of each fuel gas injection electromagnetic valve installed on a pipeline between a natural gas rail and a cylinder cover air inlet channel of the engine. The fuel oil control device is electrically connected with the electronic control pumps, and controls the starting time and the operation duration of the electronic control pump, and the electronic control pumps are installed on a pipeline between an engine fuel oil rail and a cylinder cover fuel injector.