A fuel injection control device includes an additional energization unit. Concerning an undershoot state caused by a first energization for fuel injection, a return period is an estimated period required for a movable core to return to an initial position from a first energization. An injection interval ranges from the first energization to a second energization that is for a next fuel injection. An allowable period is obtained by subtracting a rise period estimated for the second energization from the return period. The additional energization unit adds an additional energization between the first energization and the second energization when the injection interval is longer than or equal to the allowable period and is shorter than or equal to the return period.

A high-pressure pump includes a plunger that varies a volume of a pressurizing chamber, and a control valve that controls supply of fuel into the pressurizing chamber through a first valve body. When a predetermined execution condition is satisfied, an ECU reduces power supplied to a coil more than that in a normal control to implement a noise reduction control for reducing an operating noise generated along with the driving of the valve body. During the noise reduction control, a responsiveness parameter indicating responsiveness from starting energization of the coil until the valve body is displaced to a valve closing position is acquired. An energization start timing in the noise reduction control is calculated based on the acquired responsiveness parameter after the parameter is acquired. As a result, a discharge amount control of the high-pressure pump can be appropriately implemented in the noise reduction control.

When a condition for reducing a noise caused in the high-pressure pump is satisfied, a reduction control unit implements a noise reduction control to supply a smaller power to reduce a moving speed of a movable portion in a close acting direction to put a valve body into a closed state for a predetermined time after an energization start timing of a solenoid in a plunger rising period. A closing control unit causes a closing current, which is a constant current for surely putting the valve body into the closed state, to flow the closing current in the solenoid when the noise reduction control is completed in the plunger rising period. The predetermined time is shorter than an energization period in which a current flows in the solenoid.

A method is described to control an actuation profile of an electromechanical linear actuator device of an internal combustion engine designed to control the movement of a component; the internal combustion engine comprises a sensor, which faces the actuator device and is designed to detect the noise generated by the movement of the component; the method comprises the steps of acquiring, by means of the sensor, the intensity of a signal generated by the impact of the component against a limit stop; identifying a first listening window of the signal associated with said impact; calculating a noise index inside the listening window; comparing the noise index with a reference value; and controlling the actuation profile of the actuator device based on this comparison.

An example embodiment relates to a method for switching a current in an electromagnet of a switchable solenoid valve, wherein, in successive switching cycles, the current is in each case switched on in order to close the valve against a force of a spring, and thereby the current is generated by electrical connection of the electromagnet to a voltage source. The example embodiment makes provision for the current in the electromagnet to be generated with a current direction opposite to the respective previous switching cycle in at least two successive switching cycles in a switched operation of the valve.

A device and a method are provided for controlling a magnetic valve which has a coil and an armature which is displaceable by magnetic force, by means of which armature a closure element is displaceable for the purposes of injecting fuel into a combustion chamber, the method includes the steps of: energizing the coil with a voltage in accordance with a first voltage profile in order to generate a first electrical current through the coil; determining a first profile as a function of a first magnetic flux and the first current; identifying, in the first profile, a first characteristic of at least one first start of displacement at which the armature begins to displace the closure element, generating a second voltage profile and energizing the coil in accordance with the second voltage profile, such that, in a second profile, as a function of a second magnetic flux and a second current, a second characteristic of a second start of displacement is more similar to a reference characteristic than the first characteristic.

Described herein is a system for controlling a solenoid valve, which includes a driving circuit for driving a solenoid of the solenoid valve and a control unit for controlling the driving circuit. The control unit is configured for generating in the solenoid, during operation of the solenoid valve: first current signal for moving the open/close element from a first position to a second position, which is generated by the external supply network, to which the solenoid is connected; and second current signal, which is generated exclusively as a result of residual magnetism in the magnetic element of the solenoid valve and is activated when the open/close element is still in the aforesaid second position.

The subject matter of this specification can be embodied in, among other things, a method for characterizing a fluid injector that includes receiving a collection of waveform data, identifying a pull locus, determining a detection threshold level value, identifying a first subset of the collection of data representative of a selected first electrical waveform of the collection of electrical waveforms, identifying an opening value, identifying a representative closing value, identifying an anchor value, identifying a second subset of the collection of data based on the collection of data, the pull locus, the first subset, and the opening value, identifying a maximum electrical value, identifying an opening locus based the collection of data, the anchor value, and the maximum electrical value, identifying a hold value, and providing characteristics associated with the fluid injector comprising the pull locus, the opening locus, the hold value, the anchor value, and the representative closing value.

Provided is a control device of a fuel injection device which can stabilize a behavior of a valve even when a voltage of a voltage source varies, and can reduce a deviation of an injection amount. The fuel injection device includes a valve and a coil which generates a magnetic attraction force to attract a movable element which drives the valve. A control device applies a predetermined voltage to the coil on the basis of an injection pulse, causes a drive current to flow to the coil until the drive current reaches a maximum current, drives the valve by attracting the movable element, and injects fuel. The drive current flowing to the coil is lowered from the maximum current before the valve reaches a desired maximum lift position, and a constant voltage lower than a predetermined voltage or 0 V is continuously applied to the coil until the valve reaches the desired maximum lift position.

Various embodiments include a method for adjusting an initial attenuation current for an injection valve comprising: moving a piston to a TDC; while moving the piston, closing an inlet valve; expelling the fluid; moving the piston away from TDC and applying an attenuation current to an electromagnet with the inlet valve still closed; switching a source for the attenuation current off; detecting an induction pulse resulting from an opening movement of the inlet valve by monitoring a current intensity signal of a subsequent decay in the current; adjusting a current intensity over a plurality of pump cycles to a current intensity level; checking for each current intensity level whether a time profile of the induction pulse satisfies a predetermined detention criterion; and when the detention criterion is satisfied, adjusting the current intensity level for future pump cycles to a lower current intensity level than the most recent level.