Fuel injector control strategy using fuel bulk modulus for fuel injector command determination
AssigneeCaterpillar Inc.
InventorsMitchell B. Juchems, Andrew O. Marrack
Life of this patent
Estimating the term…
Abstract
A dual fuel system includes a fuel injector having a fuel pressurization plunger, and a fueling control unit structured to determine a fuel bulk modulus term based upon a volume change value (dV) and a pressure change value (dP) for a fuel pressurized in the fuel injector. The fueling control unit is further structured to determine fuel injector control commands by way of map lookups on fueling maps selected on the basis of the fuel bulk modulus term. Related apparatus and methodology are also disclosed.
Claims20
A dual fuel system comprising:
- a fuel injector including therein a plunger cavity, an injection valve, and a fuel pressurization plunger;
- a fueling control unit coupled to the fuel injector and structured to:
- determine a volume change value (dV) for a fuel containing at least one of a first fuel and a second fuel, pressurized in the fuel injector via advancing the plunger in the plunger cavity, while the fuel injector is deadheaded such that the injection valve remains closed;
- determine a pressure change value (dP) for the fuel containing at least one of the first fuel and the second fuel;
- calculate a fuel bulk modulus term based upon dV and dP;
- determine a fuel injector control command based upon the fuel bulk modulus term;
- and
- output the fuel injector control command to the fuel injector.
A method of operating a fuel system comprising:
- advancing a plunger in a plunger cavity in a fuel injector to pressurize a fuel in the plunger cavity, while the fuel injector is deadheaded such that an injection valve of the fuel injector remains closed;
- determining a volume change value (dV) for the fuel;
- determining a pressure change value (dP) for the fuel;
- outputting a fuel injector control command based upon dV and dP;
- and
- opening an injection valve in the fuel injector responsive to the fuel injector control command to inject the fuel into a cylinder in an engine.
A fuel control system comprising:
- a fueling control unit structured via control communication with a fuel injector to:
- determine a volume change value (dV) for a fuel pressurized in the fuel injector via advancing a plunger in a plunger cavity in the fuel injector, while the fuel injector is deadheaded such that an injection valve of the fuel injector remains closed;
- determine a pressure change value (dP) for the fuel pressurized in the fuel injector;
- calculate a fuel bulk modulus term indicative of a fuel type of the fuel, based upon dV and dP;
- determine a fuel injector control command for outputting to the fuel injector to control at least one of an injection pressure or an injection timing of the fuel, based upon the fuel bulk modulus term;
- and
- output the fuel injector control command to the fuel injector.
Dependencies are inferred from the claim text.