VIRTUAL TACHOMETERS BASED ON TIME SERIES FILTERING

• US 20170336430A1
• Filed: 10/19/2015
• Published: 11/23/2017
• Est. Priority Date: 12/18/2014
• Status: Active Grant

• Current Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Original Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Inventors: Winslow, Christopher L., Wu, Biqing, Davis, Mark W.
• Granted Patent: US 10,444,254 B2
• Time in Patent Office: Days
• CPC Class Codes: G01H 1/006 of the rotor of turbo machines
• CPC Class Codes: G01P 15/00 Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
• CPC Class Codes: G01P 3/48 by measuring frequency of generated current or voltage in general G01R23/00
• CPC Class Codes: G01P 3/4807 by using circuits for the detection of the pulses delivered by the ignition system of an internal combustion engine

Abstract

A system and method for receiving a plurality of first inputs from a transducer, where the plurality of first inputs correspond to vibrations of a rotational machine, and filtering the plurality of first inputs to derive a frequency of interest. The system and method then generates a sinusoidal signal at the frequency of interest and a pulse train of one or multiple pulses per revolution at the frequency of interest from the sinusoidal signal. The system and method further identifies a first pulse at a zero crossing within the pulse train and counts zero crossings to define blocks of data for use in time synchronous averaging calculations.

Claims

1. A computing device, configured to:

receive a plurality of first inputs from a transducer, the plurality of first inputs corresponding to vibrations of a rotational machine;

filter the plurality of first inputs to derive a frequency of interest;

generate a sinusoidal signal at the frequency of interest;

generate a pulse train of one or multiple pulses per revolution at the frequency of interest from the sinusoidal signal;

identify a first pulse at a zero crossing within the pulse train; and

count zero crossings to define blocks of data for use in time synchronous averaging calculations.

2. The computing device of claim 1, wherein the rotational machine is a gearbox, and wherein the transducer is an accelerometer configured to detect the vibrations of the gear box and output the vibrations to the computing device.

3. The computing device of claim 1, wherein the frequency of interest corresponds to a component of the rotational machine.

4. The computing device of claim 1, further configured to:

identify a shaft speed of the rotational device based on the identified zero-crossings.

5. The computing device of claim 1, further configured to:

process the frequency of interest in support of condition monitoring of the rotational machine.

6. Wherein the computing device of claim 1 is a virtual high speed tachometer.

7. A method, comprising:

receiving, by a computing device, a plurality of first inputs from a transducer, the plurality of first inputs corresponding to vibrations of a rotational machine;

filtering, by the computing device, the plurality of first inputs to derive a frequency of interest; and

generating, by the computing device, a sinusoidal signal at the frequency of interest;

generating, by the computing device, a pulse train of one or multiple pulses per revolution at the frequency of interest from the sinusoidal signal;

identifying, by the computing device, a first pulse at a zero crossing within the pulse train; and

counting, by the computing device, zero crossings to define blocks of data for use in time synchronous averaging calculations.

8. The method of claim 7, wherein rotational machine is a gearbox and the transducer is an accelerometer, and further comprising, detecting the vibrations of the gear box;

and

outputting the vibrations to the computing device.

9. The method of claim 7, wherein the frequency of interest corresponds to a component of the rotational machine.

10. The method of claim 7, further comprising:

identifying a rotational speed of the rotational device based on the identified zero-crossings.

11. The method of claim 7, further comprising:

processing the frequency of interest in support of condition monitoring of the rotational machine.

12. The method of claim 7, wherein the computing device is a virtual high speed tachometer.