1A - Digital Fuel Control

Question 1

What components does the Digital Fuel Control (DFC) consist of?

Answer 1

Fuel Metering Valve and Actuator
Hydrualic Pump/Servo Valve Assembly
Variable Stator Vane (VSV) Actuators with Linear Variable Differential Transformer (LVDT)
Compressor Inlet Temperature (CIT) and Pressure (CIP)

Question 2

Liquid Fuel Metering Valve (LFMV)

Answer 2

Accepts fuel from the fuel pump and delivers precisely metered amounts to the turbine.

Question 3

Electro-Hydraulic Acuator

Answer 3

Uses a spring-centered piston to provide a jump to the increase-fuel direction when a large increase signal is provided to the torque motor in the Hydraulic Pump/Servo Valve Assembly

Question 4

Hydraulic Pump/Servo Valve Assembly

Hydraulic Pump

Answer 4

Positive displacement, gear type pump operating at speeds up to 6,300 RPM @ 750 psi.

Supplies pressure to the FMV/A assembly, Servo Valve, and VSV Actuator assembly.

Question 5

Hydraulic Pump/Servo Valve Assembly

Servo Valve

Answer 5

Throttles hydraulic fluid and extends and retracts both VSV actuators.

Operates with the Hydraulic Pump and electronic control to provide a closed loop position control of the VSV actuator output shafts attached to the VSV hardware on teh gas turbine.

Question 6

VSV Actuators w/ Linear Variable Diff. Transformer (LVDT)

VSV Actuators

Answer 6

Works with the Hydraulic Pump/Servo Valve assembly to provide a closed loop control of the VSV actuator output shafts

Question 7

VSV Actuators w/ Linear Variable Diff. Transformer (LVDT)

Linear Variable Diff. Transformer (LVDT)

Answer 7

Provides exact position readout of the output position of each actuator as part of the closed loop