Digitally Controlled Fuel Metering Pump for Small Gas Turbine Engines 910057
There is a need in the gas turbine industry for an inexpensive fuel control unit for the new breed of high performance small gas turbine engines. To answer this demand, it is proposed to couple an automotive type fuel pump with a stepper motor driven in microstepping mode. The speed of the motor and the fuel flow rate can be controlled by the frequency signal from the computer. This concept is particularly well suited for the gas turbine engine fuel supply where the fuel pressure at low speed is low and the fuel leakage in the pump is not high. The stepper motor driven by a microstepping driver can reach high speeds of several thousands rpm. The unit can be installed inside the fuel, supply tank, as is the case with electric fuel pumps found in automobiles. Prototypes have been made and tested. Both steady state and transient response are showing an impressive performance of such an electronic fuel metering pump. Also, the price, as compared to that of existing fuel control units for gas turbine engines, is favorable and has the tendency to go down with the spread of stepper motor drive technology.