System and method for providing gas turbine engine output torque sensor validation and sensor backup using a speed sensor

• US 8,352,149 B2
• Filed: 10/02/2008
• Issued: 01/08/2013
• Est. Priority Date: 10/02/2008
• Status: Expired due to Fees

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Meacham, Walter L.
• Primary Examiner(s): Nguyen, Cuong H
• Application Number:
  US12/244,566
• Publication Number:
  US 20100088003A1
• Time in Patent Office: 1,559 Days
• Field of Search: 701/100, 477/30, 416 30- 31, 62115-116, 702 41- 43, 702182-185, 702 34- 35, 702/33, 738/623.21, 731/141.3, 731/141.5, 738/620.8
• US Class Current: 701/100
• CPC Class Codes: F01D 21/003 Arrangements for testing or measuring for measuring vibrations G01H
• CPC Class Codes: F01D 21/14 responsive to other specific conditions
• CPC Class Codes: F05D 2270/304 Spool rotational speed

Abstract

Methods and apparatus are provided for verifying proper operation of a gas turbine engine output torque sensor using a speed sensor, and using the speed sensor as a backup torque sensor. Gas turbine engine output torque is sensed using a reference torque sensor, and gas turbine engine output shaft rotational speed is sensed. Gas turbine engine output torque is calculated from the sensed gas turbine engine output shaft rotational speed. The sensed gas turbine engine output torque is compared to the calculated gas turbine engine output torque to determine if the reference torque sensor is operating properly. The gas turbine engine is controlled at least partially based on the sensed gas turbine engine output torque if the reference torque sensor is determined to be operating properly, and is controlled at least partially based on the calculated output torque if the reference torque sensor is determined to be not operating properly.

Claims

1. A gas turbine engine control system, comprising:

a gas turbine engine including an output shaft, the gas turbine engine adapted to receive fuel flow and, upon receipt thereof, to generate an output torque and supply the output torque via the output shaft;

a reference torque sensor operable to sense the output torque and supply a torque sensor signal representative thereof;

a speed sensor operable to sense a rotational speed of the gas turbine engine and supply a speed sensor signal representative thereof; and

an engine control operable to implement one or more control laws, based in part on the output torque and rotational speed of the gas turbine engine, the engine control coupled to receive the torque sensor signal and the speed sensor signal and further operable to;

(i) calculate the output torque from the sensed rotational speed of the gas turbine engine,

(ii) compare the sensed output torque to the calculated output torque to determine if the reference torque sensor is operating properly,

(iii) use the sensed output torque in the one or more control laws if the reference torque sensor is determined to be operating properly, and

(iv) use the calculated output torque in the one or more control laws if the reference torque sensor is determined to be not operating properly.

2. The system of claim 1, wherein the engine control determines that the reference torque sensor is not operating properly if the sensed output torque and the calculated output torque differ by a predetermined magnitude.

3. The system of claim 1, wherein:

the engine control implements a software model of the gas turbine engine, the software model configured to determine a model-based output torque; and

the engine control is further operable to compare the sensed output torque and the calculated output torque to the model-based output torque.

4. The system of claim 1, wherein the reference torque sensor comprises:

a torque shaft disposed within, and at least partially surrounded by, the output shaft, the torque shaft having a fixed end and a free end, the fixed end coupled to the output shaft, whereby the torque shaft is rotated by the output shaft; and

a sensor configured to sense rotations of the torque shaft and the output shaft and supply a signal representative thereof as the torque sensor signal.

5. The system of claim 4, wherein:

the torque sensor signal is representative of a relative rotational displacement of at least the torque shaft free end and the output shaft; and

the engine control is further operable to determine the output torque from the torque sensor signal.

6. The system of claim 4, wherein:

the torque shaft and the output shaft each comprise a plurality of evenly spaced protrusions; and

the sensor comprises a pick-up device configured to generate and supply an output voltage having an amplitude that varies based on a proximity thereto of each protrusion.

7. The system of claim 6, wherein the pick-up device is selected from a group consisting of a monopole pick-up, an eddy current sensor, and a Hall-effect sensor.

8. The system of claim 1, wherein the engine control is operable to:

differentiate the speed sensor signal to determine acceleration; and

multiply the acceleration by a predetermined inertia value to calculate the output torque.

9. The system of claim 8, wherein the predetermined inertia value is gas turbine engine inertia that is stored within the engine control.

10. The system of claim 8, wherein the engine control is further operable to filter the speed sensor signal prior to differentiation thereof.

11. The system of claim 1, wherein the speed sensor is senses rotational speed of the output shaft.

12. An engine controller, comprising:

a processor adapted to receive a torque sensor signal from a reference torque sensor and a speed sensor signal from a speed sensor, the torque sensor signal representative of a sensed engine output torque, the speed sensor signal representative of a sensed engine rotational speed, the processor configured to implement one or more engine control laws, based in part on engine output torque and engine rotational speed, the engine control operable to;

(i) calculate engine output torque from the sensed engine output shaft rotational speed,

(ii) compare the sensed engine output torque to the calculated engine output torque to determine if the reference torque sensor is operating properly,

(iii) use the sensed output torque in the one or more control laws if the reference torque sensor is determined to be operating properly, and

(iv) use the calculated engine output torque in the one or more control laws if the reference torque sensor is determined to be not operating properly.

13. The engine controller of claim 12, wherein the processor determines that the reference torque sensor is not operating properly if the sensed output torque and the calculated output torque differ by a predetermined magnitude.

14. The engine controller of claim 12, wherein the engine control is operable to:

differentiate the speed sensor signal to determine acceleration; and

multiply the acceleration by a predetermined inertia value to calculate the output torque.

15. The engine controller of claim 14, wherein the predetermined inertia value is gas turbine engine inertia that is stored within the engine control.

16. The engine controller of claim 14, wherein the engine control is further operable to filter the speed sensor signal prior to differentiation thereof.

17. A method for a gas turbine engine, comprising the steps of:

sensing gas turbine engine output torque using a reference torque sensor;

sensing gas turbine engine rotational speed;

calculating gas turbine engine output torque from the sensed gas turbine engine rotational speed;

comparing the sensed gas turbine engine output torque to the calculated gas turbine engine output torque to determine if the reference torque sensor is operating properly;

controlling the gas turbine engine at least partially based on the sensed gas turbine engine output torque if the reference torque sensor is determined to be operating properly; and

controlling the gas turbine engine at least partially based on the calculated output torque if the reference torque sensor is determined to be not operating properly.

18. The method of claim 17, wherein the step of comparing comprises:

determining if the sensed gas turbine engine output torque and the calculated gas turbine engine output torque differ by a predetermined magnitude.

19. The method of claim 17, further comprising:

differentiating the sensed gas turbine engine rotational speed to determine gas turbine engine acceleration; and

multiplying gas turbine engine acceleration by a predetermined inertia value to calculate the gas turbine engine output torque.

20. The method of claim 17, further comprising:

determining a model-based gas turbine engine output torque using a software model of the gas turbine engine; and

comparing the sensed gas turbine engine output torque and the calculated gas turbine engine output torque to the model-based gas turbine engine output torque.