An internal combustion engine, a method of operating the internal combustion engine, and a controller are disclosed. The method may be implemented in part by the controller and comprises determining a shaft angle of an engine shaft; supplying, to an ion sensor fluidly coupled to a combustion chamber of the engine a low voltage at a beginning of a combustion cycle to generate an ion sensor current and a high voltage during an ionization voltage window based at least in part on the shaft angle, wherein the low voltage is configured to prevent premature ignition of fuel in the combustion chamber and the high voltage exceeds the low voltage and is configured to increase the ion sensor current above a current threshold.

An engine-equipped vehicle capable of preventing gear noise and gear wear when the engine is started is provided. A multicylinder engine, a gear transmission that shifts power from the multicylinder engine by a shift operation, a centrifugal clutch arranged in a power transmission path from the multicylinder engine to the gear transmission, and an electronic control device that controls an operation of the multicylinder engine are included and the engine is configured to be started with a partial cylinder operation start where under control of the electronic control device, only some cylinders are operated and an operation of other cylinders is stopped.

The present invention describes a fuel-management system for minimizing particulate emissions in turbocharged direct injection gasoline engines. The system optimizes the use of port fuel injection (PFI) in combination with direct injection (DI), particularly in cold start and other transient conditions. In the present invention, the use of these control systems together with other control systems for increasing the effectiveness of port fuel injector use and for reducing particulate emissions from turbocharged direct injection engines is described. Particular attention is given to reducing particulate emissions that occur during cold start and transient conditions since a substantial fraction of the particulate emissions during a drive cycle occur at these times. Further optimization of the fuel management system for these conditions is important for reducing drive cycle emissions.

A method to control the combustion of an internal combustion engine, which comprises determining a combustion model, which provides a spark advance depending on an objective value of the rate of water to be injected, on the rotation speed, on the intake efficiency and on an open-loop contribution of a combustion index; calculating a first closed-loop contribution of the spark advance depending on the combustion index; calculating a second closed-loop contribution of the spark advance depending on a quantity indicating the knocking energy; and calculating the objective value of the spark advance angle to be operated through the sum of the spark advance value provided by the combustion model and of the first closed-loop contribution or, alternatively, of the second closed-loop contribution.

To appropriately adjust a pressure of a fuel according to a valve closing force of a fuel injection valve. To that end, a control device for an internal combustion engine includes a fuel pressure control unit that controls a pressure of a fuel supplied to a fuel injection valve that injects the fuel to an internal combustion engine. The fuel injection valve includes a plunger rod that is a valve body, a solenoid coil that is a drive unit for driving the plunger rod, and an orifice cup in which a fuel injection hole that is opened and closed according to drive of the plunger rod is formed. A cylinder pressure sensor that detects an in-cylinder pressure is attached to the internal combustion engine. The fuel pressure control unit controls the pressure of the fuel based on a pressure difference ΔP between the in-cylinder pressure detected by the cylinder pressure sensor before the plunger rod is separated from a seat portion of the orifice cup which is a valve seat and the in-cylinder pressure detected by the cylinder pressure sensor when the plunger rod is separated from the seat portion of the orifice cup.

An ignition timing control device includes a storage device that stores a normal signal generation model configured to output, upon receiving an output value of a knocking sensor, a noise-removed output value therefrom which an unlearned noise component value has been removed, and a first learned neural network pre-learned to output, upon receiving one of the output value of the knocking sensor and the noise-removed output value, an estimated value of a knocking intensity representative value, and a processor that acquires the estimated value by inputting the output value of the knocking sensor to the normal signal generation model and inputting the noise-removed output value to the first learned neural network, and executes retarding control of an ignition timing based on the acquired estimated value.

An ignition timing control device includes a storage device that stores a normal signal generation model configured to output, upon receiving an output value of a knocking sensor, a noise-removed output value therefrom which an unlearned noise component value has been removed, and a first learned neural network pre-learned to output, upon receiving one of the output value of the knocking sensor and the noise-removed output value, an estimated value of a knocking intensity representative value, and a processor that acquires the estimated value by inputting the output value of the knocking sensor to the normal signal generation model and inputting the noise-removed output value to the first learned neural network, and executes retarding control of an ignition timing based on the acquired estimated value.

The control device (50) operates to: calculate the ignition timing of each cylinder (101) of an engine (100) based on whether or not knocking is occurring; set, as a reference ignition timing, the ignition timing of any of the cylinders (101) for which the ignition timing is on the advanced angle side relative to the most retarded angle ignition timing on the most retarded angle side and on the retarded angle side relative to the most advanced angle ignition timing on the most advanced angle side; set an allowable timing difference range that is a range of an allowable timing difference with reference to the reference ignition timing; and when determining that the ignition timing of a cylinder (101) falls outside the allowable timing difference range, correct the ignition timing so that the timing difference with respect to the reference ignition timing falls within the allowable timing difference range.

The control device (50) operates to: calculate the ignition timing of each cylinder (101) of an engine (100) based on whether or not knocking is occurring; set, as a reference ignition timing, the ignition timing of any of the cylinders (101) for which the ignition timing is on the advanced angle side relative to the most retarded angle ignition timing on the most retarded angle side and on the retarded angle side relative to the most advanced angle ignition timing on the most advanced angle side; set an allowable timing difference range that is a range of an allowable timing difference with reference to the reference ignition timing; and when determining that the ignition timing of a cylinder (101) falls outside the allowable timing difference range, correct the ignition timing so that the timing difference with respect to the reference ignition timing falls within the allowable timing difference range.

Methods and systems are provided for controlling fueling and mitigating knock in internal combustion engines, such as multi-fuel engines. In one example, a method may include monitoring a frequency of knock events corresponding to one or more engine cylinders, and dynamically increasing a substitution ratio while the frequency of knock events is less than a maximum action threshold. In some examples, the method may further include actively adjusting one or more engine operating conditions to decrease the substitution ratio responsive to a severity of knocking in the one or more engine cylinders being greater than or equal to a threshold severity.