Patent ID: 9476363
Filing Date: 2016-10-25
CPC Classification: F01D,F02C,F05D

Claim Text:
1. A method for calibrating a fuel control valve assembly for a fuel system of a gas turbine engine, the fuel control valve assembly including a valve and an actuator with a rotary encoding device configured to receive a command signal from a control system of the fuel system, the method comprising: locating a preselected calibration position by measuring an effective flow area of the valve while flowing a fluid through the valve, comparing the measured effective flow area to a preselected calibration effective flow area that corresponds to the preselected calibration position, and actuating a position of the valve if the measured effective flow area does not match the preselected calibration effective flow area until the measured effective flow area matches the preselected calibration effective flow area; recording an encoder count of the rotary encoding device at the preselected calibration position; determining an encoder offset by subtracting the encoder count from a preselected calibration encoder count that corresponds to the preselected calibration position for an aligned fuel control valve assembly; determining an actual alignment encoder count by subtracting the encoder offset from an initial alignment encoder count that corresponds to a preselected alignment position for the aligned fuel control valve assembly, and associating the actual alignment encoder count with a preselected alignment command value for the command signal, the preselected alignment position being located between a minimum position of the valve and the preselected calibration position, and being at a location where the effective flow area of the valve is equal to zero; and determining an actual maximum encoder count by subtracting the encoder offset from an initial maximum encoder count, and associating the actual maximum encoder count with a maximum command value for the command signal.