VARIABLE GAS SUBSTITUTION FOR DUAL FUEL ENGINE AND METHOD
A system having an internal combustion engine connected to a driven device includes primary and secondary fuel supplies. A primary fuel supply sensor is configured to provide a primary fuel supply signal indicative of a rate of supply of a primary fuel to the engine through the primary fuel supply. A secondary fuel supply sensor is configured to provide a secondary fuel supply signal indicative of a rate of supply of a secondary fuel to the engine through the secondary fuel supply. A power output sensor measures a parameter indicative of a power output of the driven device and provides a power output signal. An electronic controller receives the primary and secondary fuel supply signals and the power output signal, and determines a characteristic of the secondary fuel based on the primary and secondary fuel supply signals and the power output signal.