Charge density control for an internal combustion engine

An apparatus for determining a value indicative of a fuel flow for an engine having an inlet air pathway, and a generator coupled with the engine to receive power from the engine, comprising:

• a speed sensor coupled with the engine and operable to determine a first characteristic indicative of an engine speed of the engine, and to transmit an engine speed signal as a function thereof;
• a load sensor coupled with the generator and operable to determine a second characteristic indicative of a load on the engine, and to transmit an engine load signal as a function thereof;
• a pressure sensor coupled with the inlet air pathway and operable to determine a value indicative of a pressure of a combustion mixture in the inlet air pathway, and to transmit a pressure signal as a function thereof;
• a temperature sensor coupled with the inlet air pathway and operable to determine a value indicative of a temperature of the combustion mixture in the inlet air pathway, and to transmit a temperature signal as a function thereof;
• and
• a processing device coupled with the first sensor to receive the engine speed signal, with the second sensor to receive the engine load signal, with the third sensor to receive the pressure signal, and with the fourth sensor to receive the temperature signal, the processing device operable to:
• determine a value indicative of a desired charge density for the combustion mixture as a function of the engine speed signal and the engine load signal;
• determine a value indicative of an actual charge density for the combustion mixture as a function of the pressure signal divided by the temperature signal;
• and
• determine a value indicative of a fuel flow for the engine as a function of the value indicative of the desired charge density and the value indicative of the actual charge density of the combustion mixture.

A method for determining a value indicative of a desired fuel flow for an engine coupled with a generator, comprising:

• determining a first characteristic indicative of an engine speed of the engine;
• determining a second characteristic that is indicative of a load on the generator;
• determining a third characteristic indicative of a pressure of the combustion mixture;
• determining a fourth characteristic indicative of a temperature of the combustion mixture;
• and
• determining a value indicative of a desired charge density for the combustion mixture as a function of the first and second characteristics.
• determining a value indicative of an actual charge density of the combustion mixture as a function of the third characteristic divided by the fourth characteristic of the combustion mixture;
• determining a value indicative of a desired fuel flow as a function of the values of the desired charge density and the actual charge density of the combustion mixture.