Method and system for controlling a crossing threshold used in determining rotational speed of a propeller

Patent metadata

Field	Value
Publication number	US-10822105-B2
Application number	US-201816129286-A
Country	US
Kind code	B2
Filing date	Sep 12, 2018
Priority date	Jul 4, 2018
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

Systems and methods for controlling a crossing threshold used in determining a rotational speed of a propeller of an aircraft engine. An initial value for the crossing threshold is set. A sensor signal is received that comprises a first series of pulses indicative of passage of position markers about a circumference of a propeller shaft. A detection signal is generated that comprises a second series of pulses indicative of within the first series of pulses that have a zero-crossing transition and a magnitude that exceeds the crossing threshold. The rotational speed of the propeller is determined from the detection signal. The crossing threshold is adjusted as a function of the rotational speed.

First claim

What is claimed is:

1. A method of controlling a crossing threshold used in determining a rotational speed of a propeller of an aircraft engine, the method comprising:
setting an initial value for the crossing threshold;
receiving a sensor signal comprising a first series of pulses indicative of passage of position markers about a circumference of a propeller shaft;
generating a detection signal comprising a second series of pulses indicative of pulses within the first series of pulses that have a zero-crossing transition and a magnitude that exceeds the crossing threshold;
determining the rotational speed of the propeller from the detection signal based on a time interval between a plurality of pulses of the second series of pulses; and
adjusting the crossing threshold as a function of the rotational speed.

2. The method of claim 1 , wherein adjusting the crossing threshold comprises:
comparing the rotational speed to a speed threshold;
when the rotational speed is less than or equal to the speed threshold, maintaining the crossing threshold at the initial value; and
when the rotational speed exceeds the speed threshold, setting the crossing threshold at an adjusted value.

3. The method of claim 2 , wherein setting the crossing threshold at the initial value comprises setting the crossing threshold at a constant value.

4. The method of claim 2 , wherein setting the crossing threshold at the initial value comprises setting the crossing threshold at a value that is a function of a peak amplitude of the sensor signal.

5. The method of claim 2 , wherein setting the crossing threshold at the adjusted value comprises setting the crossing threshold at a value that is a function of a peak amplitude of the sensor signal.

6. The method of claim 2 , wherein setting the crossing threshold comprises a controller commanding a detection device to set the crossing threshold.

7. The method of claim 6 , wherein the detection device is configured to receive the sensor signal from a sensor and to generate the detection signal.

8. The method of claim 7 , wherein setting the crossing threshold at the initial value comprises the controller commanding the detection device to operate in a first mode and commanding the detection device to set the crossing threshold at a constant value.

9. The method of claim 7 , wherein setting the crossing threshold at the initial value comprises the controller commanding the detection device to operate in a first mode and commanding the detection device to set the crossing threshold at a value that is a function of an amplitude of the sensor signal.

10. The method of claim 7 , wherein setting the crossing threshold at the adjusted value comprises the controller commanding the detection device to operate in a second mode where the crossing threshold is set at a value that is a function of an amplitude of the sensor signal.

11. A system for controlling a crossing threshold used in determining a rotational speed of a propeller of an aircraft engine, the system comprising:
at least one processing unit; and
at least one non-transitory computer-readable memory having stored thereon program instructions executable by the at least one processing unit for:
setting an initial value for the crossing threshold;
receiving a sensor signal comprising a first series of pulses indicative of passage of position markers about a circumference of a propeller shaft;
generating a detection signal comprising a second series of pulses indicative of pulses within the first series of pulses that have a zero-crossing transition and a magnitude that exceeds the crossing threshold;
determining the rotational speed of the propeller from the detection signal based on a time interval between a plurality of pulses of the second series of pulses; and
adjusting the crossing threshold as a function of the rotational speed.

12. The system of claim 11 , wherein the program instructions are executable by the at least one processing unit for adjusting the crossing threshold comprising:
comparing the rotational speed to a speed threshold;
when the rotational speed is less than or equal to the speed threshold, maintaining the crossing threshold at the initial value; and
when the rotational speed exceeds the speed threshold, setting the crossing threshold at an adjusted value.

13. The system of claim 12 , wherein the program instructions are executable by the at least one processing unit for setting the crossing threshold at the initial value comprising setting the crossing threshold at a constant value.

14. The system of claim 12 , wherein the program instructions are executable by the at least one processing unit for setting the crossing threshold at the initial value comprising setting the crossing threshold at a value that is a function of a peak amplitude of the sensor signal.

15. The system of claim 12 , wherein the program instructions are executable by the at least one processing unit for setting the crossing threshold at the adjusted value comprising setting the crossing threshold at a value that is a function of a peak amplitude of the sensor signal.

16. The system of claim 12 , wherein the program instructions are executable by the at least one processing unit for setting the crossing threshold comprising commanding a detection device to set the crossing threshold.

17. The system of claim 16 , wherein the detection device is configured to receive the sensor signal from a sensor and to generate the detection signal.

18. The system of claim 17 , wherein the program instructions are executable by the at least one processing unit for setting the crossing threshold at the initial value comprising commanding the detection device to operate in a first mode and commanding the detection device to set the crossing threshold at a constant value.

19. The system of claim 17 , wherein the program instructions are executable by the at least one processing unit for setting the crossing threshold at the initial value comprising commanding the detection device to operate in a first mode and commanding the detection device to set the crossing threshold at a value that is a function of an amplitude of the sensor signal.

20. The system of claim 17 , wherein the program instructions are executable by the at least one processing unit for setting the crossing threshold at the adjusted value comprising commanding the detection device to operate in a second mode where the crossing threshold is set at a value that is a function of an amplitude of the sensor signal.

Assignees

• Pratt & Whitney Canada

Inventors

• Yakobov Ella
• Farrell Ian

Classifications

• B64D31/06 Primary

  actuated automatically · CPC title

• G01P3/489 Primary

  Digital circuits therefor · CPC title

• F02C9/00 Primary

  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 title

• F05D2220/323

  for aircraft propulsion, e.g. jet engines · CPC title

• F02C3/06

  the compressor comprising only axial stages (F02C3/10 takes precedence) · CPC title