US6231306B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for preventing compressor stall
Assignee: RTX Corp
•
Filing: 1998-11-23
•
Granted: 2001-05-15
•
Expires: 2018-11-23
Abstract
Abstract A control system for preventing a compressor stall in a gas turbine engine includes means for sensing an aerodynamic signal indicative of an impending stall condition. The weak stages of the compressor amplify an upstream disturbance originating in the low pressure compressor or fan, resulting in a discrete frequency disturbance, which is an effective stall precursor. The control system also includes means, responsive to the sensed signal, for processing the signal by isolating the relevant frequencies of the sensed signal, calculating the magnitude of the relevant portions of the sensed signal, comparing the sensed signal to a predetermined threshold indicative of a healthy compressor, and for providing a processed signal indicative of an impending stall condition. The control system further includes means, responsive to the processed signal, for providing an output to initiate corrective action to prevent the impending stall condition. The engine's electronic control system, in response to the output signal, increases the stall margin by either adjusting the compressor variable vanes or modulating the compressor bleed.
Inventors
- 👤 Syed J. Khalid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:05
CPC Classifications
F; F04; F04D; F04D27/00; F04D27/02; F04D27/0284; F01; F01D; F01D17/00; F01D17/02; F01D17/08; F02; F02C; F02C9/00; F02C9/16; F02C9/18; F02C9/20; F04D27/001; F05; F05D; F05D2270/00; F05D2270/01; F05D2270/10; F05D2270/101
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
112 words
A control system for providing an indication of an impending compressor stall in a gas turbine engine having a low pressure compressor and a high pressure compressor, comprising: input means for sensing and providing a sensed signal indicative of the high pressure compressor static pressure in response to low pressure compressor disturbances; signal processing means, responsive to the sensed signal, for processing the sensed signal by isolating the relevant frequencies of the sensed signal, calculating the magnitude of the relevant frequency portions of the sensed signal and comparing the sensed signal to a predetermined threshold indicative of a healthy compressor, and for providing a processed signal indicative of an impending stall condition.
Claim 2
Dependent Claim
112 words
A control system for providing an indication of an impending compressor stall in a gas turbine engine having a low pressure compressor and a high pressure compressor, comprising: input means for sensing and providing a sensed signal indicative of the high pressure compressor static pressure in response to low pressure compressor disturbances; signal processing means, responsive to the sensed signal, for processing the sensed signal by isolating the relevant frequencies of the sensed signal, calculating the magnitude of the relevant frequency portions of the sensed signal and comparing the sensed signal to a predetermined threshold indicative of a healthy compressor, and for providing a processed signal indicative of an impending stall condition.
Claim 3
Dependent Claim
33 words
The control system as described in claim 1 , further includes output means, responsive to the processed signal, for providing an output signal to initiate corrective action to prevent the impending stall condition.
Claim 4
Dependent Claim
30 words
The control system as described in claim 2 , further includes an engine control means, responsive to the output signal, for modifying engine airflow geometry to increase compressor stall margin.
Claim 5
Dependent Claim
36 words
The control system as described in claim 2 , further includes a compressor bleed valve and an engine control means, responsive to the output signal, for modulating the compressor bleed valve to increase compressor stall margin.
Claim 6
Dependent Claim
42 words
The control system as described in claim 1 , wherein said signal processing means processes the sensed signal to isolate the relevant frequencies by filtering the sensed signal and providing a filtered signal indicative of frequencies related to the low pressure compressor.
Claim 7
Dependent Claim
151 words
A control system for providing an indication of an impending compressor stall in a gas turbine engine having a low pressure compressor and a high pressure compressor, comprising: input means for sensing and providing a sensed signal indicative of the high pressure compressor static pressure in response to low pressure compressor disturbances; signal processing means, responsive to the sensed signal, for processing the sensed signal by isolating the relevant frequencies of the sensed signal, calculating the magnitude of the relevant frequency portions of the sensed signal and comparing the sensed signal to a predetermined threshold indicative of a healthy compressor, and for providing a processed signal indicative of an impending stall condition; wherein said signal processing means calculates the magnitude of the relevant frequency portions of the sensed signal by calculating the mean square magnitude of the filtered signal, and by normalizing the mean square signal, and providing a normalized signal.
Claim 8
Dependent Claim
151 words
A control system for providing an indication of an impending compressor stall in a gas turbine engine having a low pressure compressor and a high pressure compressor, comprising: input means for sensing and providing a sensed signal indicative of the high pressure compressor static pressure in response to low pressure compressor disturbances; signal processing means, responsive to the sensed signal, for processing the sensed signal by isolating the relevant frequencies of the sensed signal, calculating the magnitude of the relevant frequency portions of the sensed signal and comparing the sensed signal to a predetermined threshold indicative of a healthy compressor, and for providing a processed signal indicative of an impending stall condition; wherein said signal processing means calculates the magnitude of the relevant frequency portions of the sensed signal by calculating the mean square magnitude of the filtered signal, and by normalizing the mean square signal, and providing a normalized signal.
Claim 9
Dependent Claim
49 words
The control system as described claim 6 , wherein said signal processing means compares the sensed signal to a predetermined threshold to determine if corrective action is required to prevent the impending stall condition, by comparing the normalized signal to a threshold value indicative of an impending stall condition.
Claim 10
Dependent Claim
37 words
The control system as described in claim 5 , wherein filtering of the sensed signal further includes low-pass filtering means for providing a signal having frequency components indicative of the unsteady portion of the sensed pressure signal.
Claim 11
Dependent Claim
34 words
The control system as described in claim 5 , wherein filtering of the sensed signal further includes bandpass filtering means for providing a signal having frequency components indicative of the low pressure compressor disturbances.
References Cited (Backward Citations)
US3852958A
Cited
US4117668A
Cited
US4083235A
Cited
US4196472A
Cited
US4618856A
Cited
US4608860A
Cited
US4949276A
Cited
US5165845A
Cited
US5165844A
Cited
US5594665A
Cited
US5385012A
Cited
US5375412A
Cited
US5448881A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-05-14 | 2004-11-13 | 2005-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-05-14 | 2008-11-13 | 2009-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-05-14 | 2012-11-13 | 2013-05-15 | $7700.00 | Window Closed / Lapsed |