Electronic Shaft Shear Detection Conditioning Circuit

• US 20110213537A1
• Filed: 02/26/2010
• Published: 09/01/2011
• Est. Priority Date: 02/26/2010
• Status: Active Grant

• Current Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Original Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Inventors: Dooley, Kevin Allan, Shenouda, Antwan
• Granted Patent: US 9,169,742 B2
• Time in Patent Office: Days
• US Class Current: 701/100
• CPC Class Codes: F01D 21/045 special arrangements in stators or in rotors dealing with breaking-off of part of rotor
• CPC Class Codes: F05D 2260/80 Diagnostics
• CPC Class Codes: G01R 31/2829 Testing of circuits in sensor or actuator systems testing of apparatus for measuring electric or magnetic variables G01R35/00; testing of indicating or recording apparatus G01D; in airbag systems B60R21/0173; checking gas analysers G01N33/007; monitoring or fail-safe circuits for electromagnets H01F7/1844
• CPC Class Codes: G01R 31/2831 Testing of materials or semi-finished products, e.g. semiconductor wafers or substrates G01R31/318511 takes precedence; testing during manufacture H01L22/00
• CPC Class Codes: G01R 31/2853 Electrical testing of internal connections or -isolation, e.g. latch-up or chip-to-lead connections G01R31/31717 takes precedence; test of chip-to-PCB or lead-to-PCB connections G01R31/66
• CPC Class Codes: G01R 31/2856 Internal circuit aspects, e.g. built-in test features; Test chips; Measuring material aspects, e.g. electro migration [EM]
• CPC Class Codes: G01R 31/343 in operation
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

An electrical control system for distinguishing between an electrical fault and a shaft shear condition in a gas turbine engine, the control system including, in one aspect, a detection circuit including: two or more probes, each probe including an associated resistor having a predetermined range of resistance, and each probe being disposed in the engine adjacent a rotary mounted shaft component, where mechanical interference between one or more of the probes and the shaft component renders the associated resistor substantially non-conductive; sensor processor(s) in communication with each probe, determining a probe operational status based on a measured resistance to current conducted through each probe, and generating a fault code when the measured resistance of at least one of the plurality of probes is not within the predetermined range of resistance.

Claims

1. A circuit useful for distinguishing between an electrical fault and a shaft shear failure in a gas turbine engine, the circuit comprising:

a plurality of probes, each probe associated with a resistor having a predetermined range of resistance, and each probe being disposed in an engine adjacent a rotary mounted shaft component, whereby mechanical interference between any of the plurality of probes and the shaft component renders the corresponding associated resistor substantially non-conductive;

at least one sensor processor for determining an operational status of each probe, based on a measured resistance to current conducted through each probe, and for generating a fault code when the measured resistance associated with at least one of the plurality of probes is not within the predetermined range of resistance.

2. The circuit of claim 1 wherein:

when the measured resistance associated with at least one probe is not within the predetermined range of resistance; and

when the measured resistance associated with at least one other probe is within the corresponding predetermined range of resistance;

the fault code generated by the sensor processor is an engine warning code.

3. The circuit of claim 1 wherein:

when the measured resistance associated each of the plurality of probes is not within the corresponding predetermined ranges of resistance;

the fault code generated by the sensor processor is an engine shutdown code.

4. The circuit of claim 1 wherein when a measured resistance is substantially equal to zero, the sensor processor determines the probe operational status as one of:

short circuit and probe failure.

5. The circuit of claim 1 wherein when a measured resistance is one of:

greater than zero and less than the corresponding predetermined range of resistance; and

greater than the corresponding predetermined range of resistance and less than substantially infinite resistance;

the sensor processor determines the probe operational status as;

circuit damage.

6. The circuit of claim 1 wherein when a measured resistance is substantially infinite, the sensor processor determines a probe operational status as one of:

open circuit; and

probe failure.

7. The circuit of claim 1, comprising a motor drive processor in communication with the at least one sensor processor.

8. The circuit of claim 1, comprising a fuel shutdown circuit in communication with the at least one sensor processor.

9. The circuit of claim 8, wherein the fuel shutdown circuit provides for shutdown of a fuel pump comprising a plurality of drive motors.

10. The circuit of claim 1, comprising at least one opto-isolator in communication with the at least one sensor processor.

11. The circuit of claim 1 comprising two probes.

12. The circuit of claim 11 wherein each probe is associable by the at least one sensor processor with a probe operational status selected from the group consisting of:

no-fault;

short circuit;

open circuit; and

circuit damage.

13. The circuit of claim 10, comprising four opto-isolators in communication with the at least one sensor processor.

14. A turbine engine comprising a circuit useful for distinguishing between an electrical fault and a shaft shear failure in a gas turbine engine, the circuit comprising:

a plurality of probes, each probe associated with a resistor having a predetermined range of resistance, and each probe being disposed in an engine adjacent a rotary mounted shaft component, whereby mechanical interference between any of the plurality of probes and the shaft component renders the corresponding associated resistor substantially non-conductive;

at least one sensor processor for determining an operational status of each probe, based on a measured resistance to current conducted through each probe, and for generating a fault code when the measured resistance associated with at least one of the plurality of probes is not within the predetermined range of resistance.

15. A method of monitoring shaft shear failure in a gas turbine engine, the method performed by one or more processors, each processor communicatively linked with at least one of a plurality of resistors, each resistor configured to provide a substantially open circuit in the event of a whole or partial shaft shear failure;

the method comprising;

comparing a measured resistance of each of the plurality of resistors with a corresponding predetermined range of resistance; and

generating a fault code when at least one of the measured resistances associated with at least one of the plurality of probes is not within the corresponding predetermined range of resistance.

16. The method of claim 15, comprising:

when the measured resistance of at least one probe is not within the predetermined range of resistance; and

when the measured resistance of at least one other probe is within the corresponding predetermined range of resistance, generating an engine warning code.

17. The method of claim 15, comprising:

when the measured resistance of each of the plurality of probes is not within the corresponding predetermined ranges of resistance, generating an engine shutdown code.

18. The method of claim 15, comprising:

when the measured resistance of at least one of the probes is substantially equal to zero, generating at least one of a short circuit code and a probe failure.

19. The method of claim 15, comprising, when the measured resistance of at least one of the plurality of probes is one of:

greater than zero and less than the corresponding predetermined range of resistance; and

greater than the corresponding predetermined range of resistance and less than substantially infinite resistance;

generating a circuit damage code.

20. The method of claim 15, comprising, based on the comparing a measured resistance of each of the plurality of resistors with a corresponding predetermined range of resistance:

providing to a motor drive processor communicatively linked to the at least one processor a control signal.

21. The method of claim 20, wherein the control signal comprises a signal adapted to cause shutdown of a fuel system.

22. The method of claim 21, wherein the fuel system comprises a fuel pump driven by a plurality of motors.