Various embodiments include a method for operating a fuel injector having a hydraulic stop comprising: applying a first current profile to a solenoid drive to inject a predetermined injection quantity; ascertaining a first value of a parameter correlating to a velocity of the armature when reaching the hydraulic stop; determining whether the first value of the parameter is greater than a first threshold value; and if the first value of the parameter is greater than the first threshold value, applying a second current profile to the solenoid drive to carry out a second injection procedure. The second current profile in comparison with the first current profile exerts a lower magnetic force in the direction of the pole piece on the armature.

Disclosed is a method for controlling a DC-DC voltage converter for current-driving at least one fuel injector of a motor vehicle internal combustion engine. The method notably includes the steps of determining a time referred to as the “recovery” time at which the output voltage crosses the predefined high voltage threshold, of determining a time referred to as the “drop” time, corresponding to the start of injection, at which the output voltage decreases below the predefined high voltage threshold, and of calculating the time elapsed between the recovery time and the drop time.

A fuel injection control device has a valve opening control portion which opens a control valve by electrically charging a piezoelectric element, and a valve closing portion which closes the control valve. The valve opening control portion includes a first rising control portion, a pause control portion and a second control portion. The first rising control portion increases a charge amount of the piezoelectric element during a first rising period. The pause control portion pauses an increase in the charge amount of the piezoelectric element during a pause period after the first rising period. The second rising control portion increases the charging amount of the piezoelectric elements again during a second rising period after the pause period. The pause period includes a period of immediately before the control valve is opened.

Provided is an electronic control device capable of always achieving a desired injector injection amount by preventing a change in injector opening time regardless of a change (a decrease) of a power supply voltage for opening a valve of an injector. A precharge current amount at the time of precharge control is changed in a stepwise manner based on a voltage of the injector valve open power supply device 10 at the time of the precharge control.

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.

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. A control device 150 of a fuel injection device 101 includes a valve 214, a coil 205 which generates a magnetic attraction force to attract a movable member 202 which drives the valve 214, and a voltage source. The fuel injection device 101 applies a voltage to the coil 205 on the basis of an injection pulse, causes a drive current to flow to the coil 205 until the current becomes a maximum current to attract the movable member 202, and drives the valve 214 to inject fuel. The drive current flowing to the coil 205 or a voltage of the voltage source is detected before the injection pulse is stopped. In a case where the detected drive current or the voltage is equal to or less than a setting, a width of the injection pulse or an injection pulse different from the injection pulse is corrected to be long.

A control system of an internal combustion engine comprises an air-fuel ratio sensor 40, 41 detecting an air-fuel ratio of exhaust gas, a current detecting device 61 detecting an output current of the air-fuel ratio sensor, a voltage applying device 60 applying voltage to the air-fuel ratio sensor, and a voltage control part 81 configured to control voltage applied to the air-fuel ratio sensor through the voltage applying device. The voltage control part is configured to set the applied voltage to a reference voltage determined so that the output current becomes zero when an air-fuel ratio of inflowing exhaust gas flowing into the air-fuel ratio sensor is a stoichiometric air-fuel ratio, and correct the reference voltage so that the output current detected by the current detecting device becomes zero when it is judged that the air-fuel ratio of the inflowing exhaust gas is the stoichiometric air-fuel ratio.

A control device includes a drive unit configured to supply electric power to a fuel injection valve to perform valve open drive to supply fuel to a combustion chamber of an internal combustion engine; and a correction unit configured to correct a fuel injection amount of the fuel injection valve. The correction unit is configured to learn the fuel injection amount of the fuel injection valve when NOx purge is performed to reduce and purify the NOx occlusion catalyst.

The present invention provides a high-efficiency and highly-reliable fuel injection control device that controls a fuel injection valve of an internal combustion engine and can perform injection amount control in accordance with a deterioration degree of the fuel injection valve. A fuel injection control device controlling a fuel injection valve of an internal combustion engine includes a deterioration determination unit that determines a deterioration state of the fuel injection valve, an injection amount learning unit that learns the injection amount of the fuel injection valve, and a learning frequency change unit that changes the learning frequency of the injection amount learning unit in accordance with the deterioration state of the fuel injection valve.

A method for sensing a closing time of an injector using an artificial neural network may include: sensing, by a controller, a voltage generated by an injector; performing, by the controller, a preprocess to derive an input matrix using variation characteristics of the voltage; and performing, by the controller, a closing time prediction to derive a closing time of the injector by an artificial neural network model including an input layer including the input matrix, a hidden layer, and an output layer.