Electrically driven fuel pump for gas turbine engines
First Claim
1. An electrically powered fuel control for a gas turbine engine comprising:
- (a) an electrically powered fuel supply means for providing fuel to the gas turbine engine in response to a power signal, the fuel supply means providing an increased fuel supply to cause the engine to provide increased power and a decreased fuel supply to the engine to cause the engine to provide decreased power;
(b) means for specifying fuel demand for the engine to selectively cause the increase in fuel supplied to the engine and the decrease in fuel supplied to the engine, the means for specifying producing a fuel flow demand signal which is proportional to the specified fuel demand;
(c) sensing means for producing a signal which is proportional to a sensed velocity of a moving element in the electrically powered fuel supply means;
(d) means for braking the rate of delivery of fuel by the electrically powered fuel supply means in response to a braking signal; and
(e) control means, responsive to the velocity signal and the fuel flow demand signal, for producing the power signal to cause an increase in the supply of fuel delivered to the engine in response to the means for specifying fuel demand specifying an increase in the rate of delivery of fuel to the engine and for applying power to cause a decrease in the rate of delivery of fuel delivered to the engine less in magnitude than a predetermined rate of decrease, in response to the means for specifying fuel demand specifying a decrease in rate of delivery of fuel less than the predetermined rate of decrease and for producing the braking signal for causing the electrically powered fuel supply means to be braked by the means for braking to decrease the rate of delivery of fuel to the engine in response to the means for specifying fuel demand specifying a decrease in the rate of delivery of fuel greater than the predetermined rate of decrease in the rate of delivery.
1 Assignment
0 Petitions
Accused Products
Abstract
An improved electrically driven fuel control system for a gas turbine engine is disclosed. The system utilizes a combination of variation in power applied to an electrically powered drive of a positive displacement fuel pump and braking to achieve an optimized response characteristic approaching that of mechanically driven fuel systems directly driven from the gas turbine engine. In the preferred embodiment, for a decrease in fuel delivery exceeding a predetermined limit control of the electric drive for the fuel pump is achieved by braking. For decreases in fuel delivery having a magnitude less than the predetermined limit and for fuel increases, control is achieved by varying the power applied to the electric drive for the fuel pump.
39 Citations
12 Claims
-
1. An electrically powered fuel control for a gas turbine engine comprising:
-
(a) an electrically powered fuel supply means for providing fuel to the gas turbine engine in response to a power signal, the fuel supply means providing an increased fuel supply to cause the engine to provide increased power and a decreased fuel supply to the engine to cause the engine to provide decreased power; (b) means for specifying fuel demand for the engine to selectively cause the increase in fuel supplied to the engine and the decrease in fuel supplied to the engine, the means for specifying producing a fuel flow demand signal which is proportional to the specified fuel demand; (c) sensing means for producing a signal which is proportional to a sensed velocity of a moving element in the electrically powered fuel supply means; (d) means for braking the rate of delivery of fuel by the electrically powered fuel supply means in response to a braking signal; and (e) control means, responsive to the velocity signal and the fuel flow demand signal, for producing the power signal to cause an increase in the supply of fuel delivered to the engine in response to the means for specifying fuel demand specifying an increase in the rate of delivery of fuel to the engine and for applying power to cause a decrease in the rate of delivery of fuel delivered to the engine less in magnitude than a predetermined rate of decrease, in response to the means for specifying fuel demand specifying a decrease in rate of delivery of fuel less than the predetermined rate of decrease and for producing the braking signal for causing the electrically powered fuel supply means to be braked by the means for braking to decrease the rate of delivery of fuel to the engine in response to the means for specifying fuel demand specifying a decrease in the rate of delivery of fuel greater than the predetermined rate of decrease in the rate of delivery. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. An electrically powered fuel control for a gas turbine engine comprising:
-
(a) an electrically powered fuel supply means for providing fuel to the gas turbine engine in response to a power signal, the fuel supply means providing an increased fuel supply to cause the engine to provide increased power and a decreased fuel supply to the engine to cause the engine to provide decreased power; (b) means for specifying fuel demand for the engine to selectively cause the increase in fuel supplied to the engine and the decrease in fuel supplied to the engine, the means for specifying producing a fuel flow demand signal which is proportional to the specified fuel demand; (c) sensing means for producing a signal which is proportional to a sensed velocity of a moving element in the electrically powered fuel supply means; (d) means for braking the rate of delivery of fuel by the electrically powered fuel supply means in response to a braking signal; and (e) control means, responsive to the velocity signal and the fuel flow demand signal, for producing the braking signal and the power signal for respectively controlling the electrically powered fuel supply means and the braking means in accordance with a response characteristic having three sections;
in a first section the braking means being activated by the braking signal for rates of decrease of fuel greater than a predetermined rate of decrease of fuel specified by the means for specifying, in a second section the electrically powered fuel supply means being activated by the power signal for rates of decrease of fuel less than the predetermined rate of decrease specified by the means for specifying and in a third section the electrically powered fuel supply means being activated by the power signal for rates of increase of fuel specified by the means for specifying.
-
Specification