Patent ID: 7051535

Claim:
A system for accurately measuring parameters of a gas turbine engine output, the gas turbine engine having a power turbine and providing power to a controllable device via an output shaft coupling said device to said engine, said system utilizing a first differential pressure across said power turbine and comprising: a means for measuring the initial temperature and initial pressure of the inlet air entering the gas engine; a combustor and a gas-generating turbine to combust said inlet air and produce expanding gas; a differential pressure sensor; a first pressure tap positioned between said gas-generating turbine and said power turbine, said first tap taking a first pressure reading of said expanded gas as said expanded gas travels from said gas-generating turbine to said power turbine and providing said first pressure reading to said differential pressure sensor, an exhaust port located adjacent to said power turbine to allow said expanded gas to escape said engine upon leaving said power turbine; a second pressure tap positioned in said exhaust port, said second tap taking a second pressure reading of said escaping gas and providing said second pressure reading to said differential pressure sensor, said differential pressure sensor producing a first differential pressure signal in response to said first and second pressure readings; a speed sensor coupled to determine the rotational speed of said power turbine and produce a speed signal; a processor coupled to receive said initial temperature and pressure measurements, said first differential pressure signal and said speed signal and process said measurements and pressure and speed signals to produce an accurate torque signal of said engine, said torque signal being used to maintain a precise control of the power output of said controllable device.