METHOD FOR PREDICTING AN AUXILIARY POWER UNIT FAULT

• US 20150096359A1
• Filed: 04/30/2014
• Published: 04/09/2015
• Est. Priority Date: 10/07/2013
• Status: Active Grant

• Current Assignee: GE Aviation Systems Limited (GE Aerospace)
• Original Assignee: GE Aviation Systems Limited (GE Aerospace)
• Inventors: Catt, Christopher Joseph
• Granted Patent: US 9,437,054 B2
• Time in Patent Office: Days
• US Class Current: 73/112.01
• CPC Class Codes: B64D 2045/0085 Devices for aircraft health monitoring, e.g. monitoring flutter or vibration
• CPC Class Codes: B64D 41/00 Power installations for auxiliary purposes
• CPC Class Codes: F01D 17/02 Arrangement of sensing elements
• CPC Class Codes: F01D 17/20 Devices dealing with sensing elements or final actuators or transmitting means between them, e.g. power-assisted sensing elements alone F01D17/02; final actuators alone F01D17/10
• CPC Class Codes: F01D 21/003 Arrangements for testing or measuring for measuring vibrations G01H
• CPC Class Codes: F02C 9/00 Controlling gas-turbine plants; Controlling fuel supply in air- breathing jet-propulsion plants controlling air intakes F02C7/057; controlling turbines F01D; controlling compressors F04D27/00; controlling in general G05
• CPC Class Codes: F05D 2220/50 for auxiliary power units (APU's)
• CPC Class Codes: F05D 2260/80 Diagnostics
• CPC Class Codes: F05D 2270/3032 excessive temperatures, e.g. caused by overheating
• CPC Class Codes: F05D 2270/304 Spool rotational speed
• CPC Class Codes: F05D 2270/44 active, predictive, or anticipative
• CPC Class Codes: G07C 5/008 communicating information to a remotely located station transmission systems for measured values G08C
• CPC Class Codes: G07C 5/0808 Diagnosing performance data testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005

Abstract

A method of predicting an auxiliary power unit fault in an aircraft having an auxiliary power unit and multiple sensors related to the auxiliary power unit, components thereof, and systems related thereto, including receiving a sensor signal from at least one of the multiple sensors to define a sensor output, comparing the sensor output to a reference value and predicting a fault in the auxiliary power unit based on the comparison.

Claims

1. A method of predicting an auxiliary power unit fault in an aircraft having an auxiliary power unit and multiple sensors related to the auxiliary power unit, components thereof, and systems related thereto, the method comprising:

receiving, during pre-flight or post-flight, a sensor signal from at least one of the multiple sensors to define a sensor output;

comparing, by a controller, the sensor output to a reference value for the sensor output;

predicting, by a controller, a fault in the auxiliary power unit based on the comparison; and

providing, by a controller, an indication of the predicted fault.

2. The method of claim 1, further comprising receiving at least one of an altitude signal, a speed signal, and performances parameters outputted by an engine.

3. The method of claim 2, further comprising determining when the aircraft is in pre-flight or post-flight.

4. The method of claim 2 wherein the fault is predicted when the comparison indicates that an exhaust gas temperature, during the post-flight, is greater than a predetermined temperature.

5. The method of claim 1 wherein the received sensor output is aggregated over time to define aggregated sensor data, and the comparison comprises comparing the aggregated sensor data to the reference value.

6. The method of claim 5 wherein the aggregating the received sensor output over time comprises aggregating the received sensor output over multiple flights.

7. The method of claim 5 wherein the aggregated sensor data comprises at least one of a median value, a running median value, or a historical median value.

8. The method of claim 7 wherein the fault is predicted when the comparison indicates that a median inlet temperature in the pre-flight was greater than 45 degrees Celsius.

9. The method of claim 1 wherein the reference value is calculated from historical sensor output.

10. The method of claim 1 wherein the fault is predicted when the comparison indicates a surge control valve position in the post-flight was less than −

0.5 degrees or greater than 0.5 degrees.

11. The method of claim 1, further comprising determining from the sensor output a time taken for the auxiliary power unit to start and wherein the determined time is compared to the reference value.

12. The method of claim 11 wherein the fault is predicted when the comparison indicates the time taken for the auxiliary power unit to start up was greater than 50 seconds.

13. The method of claim 1 wherein providing the indication comprises providing the indication on a PFD in a cockpit of the aircraft.

14. The method of claim 1 wherein the predicting the fault is based on multiple comparisons.