BLEED VALVE OVERRIDE SCHEDULE ON OFF-LOAD TRANSIENTS

摘要

In one aspect, the present disclosure is directed to a method for controlling a position of a bleed valve of a gas turbine engine. The onset of an off-load transient may be determined. Values representative of the turbine rotor inlet temperature and the exhaust outlet temperature may be determined. Also, the amount of time elapsed since the onset of the off-load transient may be determined. Three provisional bleed valve command positions may be determined based on value representative of the turbine rotor inlet temperature, the value representative of the exhaust outlet temperature, and the amount of time elapsed, respectively. The provisional bleed valve command position associated with the lowest relative value may be selected. Then, the bleed valve position may be adjusted to match the selected bleed valve command position.

主权项

1. A method for controlling a position of a bleed valve of a gas turbine engine, comprising:
a) determining an onset of an off-load transient; b) determining a value representative of a turbine rotor inlet temperature, a value representative of an exhaust outlet temperature, and an amount of time elapsed since onset of the off-load transient; c) determining a first provisional bleed valve command position value based on the value representative of the turbine rotor inlet temperature; d) determining a second provisional bleed valve command position based on the value representative of the exhaust outlet temperature; e) determining a third provisional bleed valve command position based on the time elapsed since onset of the off-load transient; f) determining which of the first, second, and third provisional bleed valve command positions is associated with a lowest relative value and selecting the provisional bleed valve command position associated with the lowest relative value; and g) adjusting the position of the bleed valve to match the selected bleed valve command position.