Fuel control circuit for a turbine engine

A fuel control circuit for a turbine engine, comprising:

• first means for measuring output power of said turbine engine;
• means for determining a first value of minimum fuel demand necessary to prevent extinction of said turbine engine during operation when a magnitude of said output power is at a low-load level of operation less than a predefined threshold value;
• means for causing said first value of minimum fuel demand to be stored, said causing means being connected in signal communication with said first measuring means with an input of said causing means being coupled to an output of said first measuring means, said causing means being connected in signal communication with said determining means with an output of said causing means being coupled to an input of said determining means;
• and
• means for preventing said fuel demand from decreasing below said first value of minimum fuel demand during operation, said preventing means being connected in signal communication with said determining means with an input of said preventing means being coupled to an output of said determining means.

A fuel control system for a turbine engine, comprising:

• first means for providing a first signal representative of a magnitude of output power of said turbine engine;
• means for comparing said first signal to a predetermined threshold value, said comparing means being connected in signal communication with said first providing means;
• second means for providing a second signal representative of a fuel demand of said turbine engine;
• third means for providing a third signal representative of a minimum fuel demand of said turbine engine necessary to prevent flameout, said third providing means comprising a means for periodically adjusting said third signal during low-level operation in response to changes in said second signal altered by said first signal, said periodic adjusting means being connected in signal communications with said second providing means;
• and means, connected in signal communication with said periodic adjusting means, for inhibiting said periodic adjusting means, said inhibiting means being connected in signal communication with an output of said comparing means, said inhibiting means being responsive to a fourth signal form said output of said comparing means, said fourth signal being representative of a predefined relationship between said first signal and said predefined threshold value.

A fuel control system for a turbine engine, comprising:

• first means for providing a first signal representative of a magnitude of output power of said turbine engine;
• means, connected in signal communication with said first providing means for comparing said first signal with a predefined threshold value;
• second means for providing a second signal representative of a fuel demand of said turbine engine;
• and
• third means, connected in signal communication with said second providing means, for providing a third signal representative of a minimum fuel demand of said turbine engine necessary to prevent extinction, said third providing means being operative to adjust said third signal during low-load operation of said turbine engine, said third providing means being connected in signal communication with said first comparing means and being responsive to a fourth signal from said first comparing means, said fourth signal being generated by said first comparing means upon the occurrence of a predefined relationship between said first signal and said predefined threshold value, said third providing means being adapted to maintain the magnitude of said third signal in response to said fourth signal.

A fuel control system for a turbine engine, comprising:

• a sensor configured to provide a first signal representative of the output power of said turbine engine;
• a load threshold circuit connected in signal communication with said sensor, said load threshold circuit being configured to compare said first signal with a predefined threshold value;
• means for providing a second signal representative of fuel demand of said turbine engine;
• a counter connected in signal communication with said providing means for maintaining a digital value representative of said second signal altered by said first signal;
• a converter connected to said counter, said converter providing a third signal, said third signal being an analog representation of said digital value;
• a fuel level detector having inputs coupled to said first, second and third signals and an output connected in signal communication with said counter, said detector providing a signal to said counter which causes said counter to change said digital value in response to a predefined relationship between said first, second and third signals;
• and
• said load threshold circuit providing a fourth signal when said first signal exceeds said predefined threshold value, said counter being connected in signal communication with said load threshold circuit, said counter being configured to be inhibited in response to said fourth signal from changing the magnitude of said digital value in response to said fourth signal.