Methods and systems are provided for balancing a plurality of fuel injectors. In one example, a method includes determining a fuel injector error shape and applying a fueling correction to all injectors based on the fuel injector error shape.

Provided is a sensorless control device for a DC fuel pump that may be downsized as compared to a conventional control device for a DC fuel pump and may implement the same operation at a relatively low cost, and the sensorless control device for a DC fuel pump.

Systems and methods for improving accuracy of an amount of fuel injected to an engine are disclosed. In one example, holding current of a fuel injector is adjusted to follow a fixed period and timing of a fuel injector off command is adjusted according to attributes of fuel injector holding current so that a fuel injector may provide a requested fuel amount. The fuel injector off command may be adjusted according to an amount of holding current that is expected to be flowing through the fuel injector at a time when the fuel injector is commanded off.

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 determining a static flow rate of a piezo-electric injector of an injection system. The piezo-electric injector includes a needle and a piezo-electric actuator designed to control a valve of the injector. The injection system includes an electric generator designed to send electric current pulses to the piezo-electric actuator of the injector, and a voltage sensor designed to measure voltage values at the terminals of the piezo-electric actuator. The method includes the following steps: sending during a phase of closure of the needle of an electric current pulse such that the piezo-electric actuator is positioned in contact with the valve, without giving rise to the opening thereof; measurement of a plurality of voltage values of the piezo-electric actuator; and determining a static flow rate of the piezo-electric injector on the basis of a plurality of voltage values measured of the piezo-electric actuator.

An injection control device includes: a boost controller performing a boost switching control of a boost switch to charge a boost capacitor and supplying a boost power from a battery power supply; a boost voltage monitor monitoring the boost voltage; and a boost monitor timing controller setting a section from a predetermined time after an on-edge of the boost switch to an off-edge timing in a section monitor mode as a boost monitor section. The boost controller stops boosting by stopping the boost switching control when the boost voltage is equal to or higher than a boost stop threshold value in the boost monitor section.

Operating an engine system and fuel system includes energizing a solenoid actuator for a spill valve in a fuel injector in a first engine cycle via a standard waveform to inject a shot of fuel. Operating an engine system and fuel system further includes determining suitability for reduced energy operating of the fuel system, and energizing the solenoid actuator via a reduced energy waveform based on the determining suitability so as to inject one or more shots of fuel in a second engine cycle. The operating methodology and control logic can extend an engine speed range for multi-shot fuel injection in an engine.

There is provided a transformation control device of a transformation chopper circuit that transforms an input by turning on and off a current using a switch and outputs the transformed input. The transformation control device controls at least an ON/OFF state of a main switch by acquiring an output voltage of the transformation chopper circuit in a case where the main switch is in an ON state, the main switch being turned on in a case where energy is accumulated in an inductor.

Appropriate detection of an abnormality of voltage information, which is a basis for correcting a fuel injection amount, becomes possible. For this reason, a fuel injection control device 127, which has a drive IC 208 controlling a fuel injection drive unit 207a to supply a high voltage to a solenoid 405 so as to open a fuel injection valve 105 and controlling the fuel injection drive unit 207a to supply a low voltage to the solenoid 405 so as to hold a valve-open state of the fuel injection valve 105, includes: a drive voltage input unit 211 that measures and outputs voltage information based on an upstream voltage of the solenoid 405 of the fuel injection valve 105 and a downstream voltage of the solenoid 405; a fuel injection amount correction unit 213 that corrects a fuel injection amount of the fuel injection valve 105 based on the voltage information output from the drive voltage input unit 211; and a voltage input function abnormality detection unit 212 that detects whether an output of the drive voltage input unit 211 is abnormal based on the voltage information output from the drive voltage input unit 211.

When injecting fuel from a fuel injection valve by energizing thereof, an energization time correction amount calculator performs an area correction of an electric current flowing in the fuel injection valve, and calculates an energization time correction amount. An injection instruction state determiner determines an inter-cylinder injection instruction interval among cylinders which inject fuel in series or determines an injection instruction overlapping state. An upper guard value setter sets an upper guard value of the energization time correction amount based on the inter-cylinder injection instruction state determined by the injection instruction state determiner.