Low noise control of a high-pressure fuel pump is performed by reducing noise generated by an anchor colliding with a fixing core. A control device 800 for a high-pressure fuel pump controls a suction valve that opens and closes an inflow port through which fuel flows to a pressurizing chamber by performing energization to a solenoid 205 in synchronization with a reciprocating motion of a plunger. A current energized to the solenoid 205 includes a peak current for giving a force to start closing a valve to the suction valve in a stationary state and a holding current for performing switching in a range smaller a maximum value of the peak current in order to hold the suction valve in a valve closing state. When the control device 800 reduces a peak current application amount of the peak current from a value sufficient to close the high-pressure fuel pump, a valve closing speed of the suction valve becomes small up to a certain application amount, and when the peak current application amount becomes smaller than the application amount, there is a saturation range of a current application amount of the peak current in which the valve closing speed of the suction valve is saturated. The control device 800 controls the current application amount of the peak current to fall in the saturation range.

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 metering valve supplies fuel to and block fuel from a pressurizing chamber by moving a valve body by switching between energization and de-energization of an electromagnetic unit. An energization control unit performs a valve closing control and a valve opening control to reduce operating sound in one opening and closing period in which the valve body opens and closes. A time control unit controls, on determination that the energizing period of the electromagnetic unit exceeds the upper limit value, a moving speed of the valve body when the valve body moves to a valve closing side, such that the energization period of the electromagnetic unit in the one opening and closing period does not exceed the upper limit value, thereby to cause the energization control unit to perform both the valve closing control and the valve opening control in the one opening and closing period.

A method (100) is proposed for operating an internal combustion engine (210), which comprises a lean-burn engine having compression-ignition, having a throttle valve (213) in an air path (212) upstream of the internal combustion engine (210) and an exhaust gas posttreatment system (202) downstream of the internal combustion engine (210), comprising a control of the internal combustion engine (210) according to a present load demand (130) using metering of an amount of fuel in dependence on the present load demand; and if a load demand (130) is absent in a heating operating mode, further comprising partially closing (140) the throttle valve (213) and defining a minimum value for the amount of fuel, which is greater than zero. Furthermore, a computing unit and a computer program for carrying out such a method (100) are proposed.

This signal processing device comprises: an acquisition unit for acquiring an acoustic signal; a measurement unit for measuring an acoustic level of the acoustic signal for every one of first frequency bands, which are a plurality of frequency bands of a preset first bandwidth; a calculation unit that, on the basis of the plurality of acoustic levels of the first frequency bands, identifies an acoustic feature quantity indicating the separation degree from normal acoustic levels of second frequency bands, which are a plurality of frequency bands of a second bandwidth that is wider than the first bandwidth; a first determination unit for determining whether the acoustic levels measured for every one of the first frequency bands are a first threshold value or greater; and a second determination unit for determining whether the acoustic feature quantity is a second threshold value or greater.

Various methods and systems are provided for controlling air flow through an engine by adjusting an electric turbocharger of a vehicle. In one embodiment, a system for a vehicle comprises an electric turbocharger comprising a compressor, an exhaust turbine coupled to the compressor via a shaft, and an electric machine mechanically coupled to the shaft; and a controller including a processor and instructions stored on a non-transient memory of the controller that, when executed, cause the controller to: adjust an amount of power provided to or extracted from the shaft by the electric machine based on at least one of a speed of the electric turbocharger, a cylinder pressure, and an exhaust gas temperature. By adjusting the amount of power provided to or extracted from the electric machine, the exhaust gas temperature and the speed of the electric turbocharger may be efficiently maintained within a desired operating range.

A piston engine is provided; the piston engine has a cylinder, a main piston and an auxiliary piston; a combustion chamber is formed between the main piston and the auxiliary piston within the cylinder; the main piston has an crankpin offset L0, the auxiliary piston and the main piston move in different frequencies, an extended constant V≈Vc of the combustion chamber is formed from θ to >10° CA; when at a=θ=arc sin[L0/(L+R)] the main piston is at its top dead center; at a=arc sin(L0/R) the side force on the main piston is 0; when peak pressure of combustion is located at PPmax by choosing ignition timing, the most effective torque can be obtained; the torque is controlled by the amount of fuel injected; engine knocking can be prevented by retarded ignition at a>θ.

A method and a system for adjusting a base idle speed of an engine are described. In one example, the method reduces engine speed according to output of a sensor that senses mechanical vibrations. Once a vibration level exceeds a threshold, engine speed reduction ceases and the base engine idle speed is adjusted according to a present engine speed.

To provide a controller and a control method for internal combustion engine which can suppress the increase in the calculation processing load for determining occurrence of the mechanical noise and occurrence of the knocking with good accuracy even when the mechanical noise occurs. When the maximum value of the strength of the component of the second frequency band in the comparison period exceeds the maximum value of the strength of the component of the first frequency band, a controller for internal combustion engine performs a second side stop determination processing that determine whether the knocking occurred, based on the strength of the component of the first frequency band, without using the strength of the component of the second frequency band.

Various methods and systems are provided for controlling air flow through an engine by adjusting an electric turbocharger of a vehicle. In one embodiment, a system for a vehicle comprises an electric turbocharger comprising a compressor, an exhaust turbine coupled to the compressor via a shaft, and an electric machine mechanically coupled to the shaft; and a controller including a processor and instructions stored on a non-transient memory of the controller that, when executed, cause the controller to: adjust an amount of power provided to or extracted from the shaft by the electric machine based on at least one of a speed of the electric turbocharger, a cylinder pressure, and an exhaust gas temperature. By adjusting the amount of power provided to or extracted from the electric machine, the exhaust gas temperature and the speed of the electric turbocharger may be efficiently maintained within a desired operating range.