Stephen F Doherty

US Patent:

61419516, Nov 7, 2000

Filed:

Aug 18, 1998

Appl. No.:

9/135622

Inventors:

Leon Krukoski - Coventry CT
Nicola Laudadio - Vernon CT
Stephen P. Doherty - Unionville CT
Merrill L. Kratz - South Windsor CT

Assignee:

United Technologies Corporation - Hartford CT

International Classification:

F02C 1310

US Classification:

60 3902

Abstract:

A control system for operating a compressor bleed valve in a gas turbine engine to prevent compressor operation in surge region determines engine stability in response to a plurality of sensed engine parameters, and calculates and stores engine parameters to estimate compressor performance relative to a stability limit which is indicative of a surge operation. The control system further maintains a rolling average of the estimate of compressor performance for up to a predetermined number of engine flights. This rolling average of the estimate of compressor performance is indicative of engine usage and associated engine degradation. The control system determines a bias for the bleed valve in response to calculated engine parameters and adjusts the operation of the bleed valve in response to the compressor performance so as not to exceed the stability limit.