US 10,378,475 B2 · Method for determining a reference current value for actuating a fuel injector

Abstract

A method for determining a reference current value for actuating a fuel injector, comprising a solenoid drive, for an internal combustion engine of a motor vehicle is described. The method comprises the following: (a) acquiring a multiplicity of current profiles with repeated actuation of the fuel injector, wherein each current profile has a temporal progression of the current strength of a current flowing through the solenoid drive, and wherein each actuation of the fuel injector comprises the following steps: (aa) applying a boost voltage to the solenoid drive of the fuel injector until the current strength of the current flowing through the solenoid drive reaches a first predetermined value, (ab) waiting for the current strength to reach a second predetermined value during a first free-wheeling phase, (ac) applying the boost voltage to the solenoid drive again until the current strength reaches the first predetermined value, and (ad) waiting for the current strength to reach the second predetermined value during a second free-wheeling phase, wherein the first predetermined value is varied for each actuation, the method also comprising (b) determining a multiplicity of magnetic flux profiles, wherein each magnetic flux profile corresponds to one of the multiplicity of acquired current profiles, and (c) selecting the reference current value on the basis of an analysis of the associated current profiles and magnetic flux profiles.

Claims20

Dependent claims

A method for actuating a fuel injector comprising a solenoid drive, for an internal combustion engine of a motor vehicle, the method comprising:

acquiring a plurality of current profiles with repeated actuation of the fuel injector, wherein each current profile has a temporal progression of a current strength of a current flowing through the solenoid drive, and wherein each actuation of the fuel injector comprises:
applying a first boost voltage to the solenoid drive of the fuel injector until the current strength of the current flowing through the solenoid drive reaches a first predetermined value;
waiting for the current strength of the current flowing through the solenoid drive to reach a second predetermined value during a first free-wheeling phase;
applying a second boost voltage to the solenoid drive until the current strength of the current flowing through the solenoid drive reaches the first predetermined value;
and
waiting for the current strength of the current flowing through the solenoid drive to reach the second predetermined value during a second free-wheeling phase;
wherein the first predetermined value is varied for each actuation, the method also comprises:
determining a plurality of magnetic flux profiles, wherein each magnetic flux profile corresponds to one of the plurality of acquired current profiles, and
selecting a reference current value on the basis of an analysis of the current profiles and the magnetic flux profiles.

6 more elements

A computer program product stored on a non-transitory memory and having instructions which, when executed by a control unit for an engine of a motor vehicle having a fuel injector with a solenoid drive, causes the control unit to:

acquire a plurality of current profiles with repeated actuations of the fuel injector, wherein each current profile has a temporal progression of a current strength flowing through the solenoid drive, and wherein each actuation of the fuel injector comprises:
apply a first boost voltage to the solenoid drive of the fuel injector until the current strength flowing through the solenoid drive reaches a first predetermined value;
upon the current strength reaching the first predetermined value, wait for the current strength of the current through the solenoid drive to reach a second predetermined value during a first free-wheeling phase;
upon the current strength of the current through the solenoid drive reaching the second predetermined value, apply a second boost voltage to the solenoid drive until the current strength reaches the first predetermined value;
and
upon the current strength reaching the first predetermined value, wait for the current strength to reach the second predetermined value during a second free-wheeling phase;
wherein the first predetermined value is varied for each actuation,
determine a plurality of magnetic flux profiles, wherein each magnetic flux profile corresponds to a distinct one of the plurality of acquired current profiles, and
select a reference current value based on the current profiles and the magnetic flux profiles.

6 more elements

A controller for an engine of a motor vehicle, the engine including a fuel injector, the controller configured to:

acquire a plurality of current profiles with repeated actuations of the fuel injector, wherein each current profile has a temporal progression of a current strength flowing through the solenoid drive, and wherein each actuation of the fuel injector comprises:
apply a first boost voltage to the solenoid drive of the fuel injector until the current strength flowing through the solenoid drive reaches a first predetermined value;
upon the current strength reaching the first predetermined value, wait for the current strength of the current through the solenoid drive to reach a second predetermined value during a first free-wheeling phase;
upon the current strength reaching the second predetermined value, apply a second boost voltage to the solenoid drive until the current strength reaches the first predetermined value;
and
upon the current strength reaching the first predetermined value, wait for the current strength to reach the second predetermined value during a second free-wheeling phase;
wherein the first predetermined value is varied for each actuation,
determine a plurality of magnetic flux profiles, wherein each magnetic flux profile corresponds to one of the plurality of acquired current profiles, and
select a reference current value based on the current profiles and the magnetic flux profiles.

6 more elements

Dependencies are inferred from the claim text.

Method for determining a reference current value for actuating a fuel injector

Life of this patent

Method for determining a reference current value for actuating a fuel injector

Life of this patent

Abstract

Claims20