Fingerprinting of fluid injection devices

• US 10,401,398 B2
• Filed: 03/03/2017
• Issued: 09/03/2019
• Est. Priority Date: 03/03/2017
• Status: Active Grant

• Current Assignee: Woodward Incorporated
• Original Assignee: Woodward Incorporated
• Inventors: Shahroudi, Kamran Eftekhari, Nair, Suraj
• Primary Examiner(s): Rivera Vargas, Manuel A
• Assistant Examiner(s): Perez Bermudez, Yaritza H
• Application Number:
  US15/449,514
• Publication Number:
  US 20180252752A1
• Time in Patent Office: 914 Days
• CPC Class Codes: F02D 2041/2037 for preventing bouncing of the valve needle
• CPC Class Codes: F02D 2041/2048 said control involving a limitation, e.g. applying current or voltage limits
• CPC Class Codes: F02D 2041/2055 with means for determining actual opening or closing time
• CPC Class Codes: F02D 2200/0618 Actual fuel injection timing or delay, e.g. determined from fuel pressure drop
• CPC Class Codes: F02D 2200/063 Lift of the valve needle
• CPC Class Codes: F02D 41/20 Output circuits, e.g. for controlling currents in command coils
• CPC Class Codes: F02D 41/2096 for controlling piezoelectric injectors drive and control circuit for piezoelectric devices in general H10N30/802
• CPC Class Codes: F02D 41/221 relating to the failure of actuators or electrically driven elements
• CPC Class Codes: F02D 41/2422 Selective use of one or more tables
• CPC Class Codes: F02D 41/2467 for injectors
• CPC Class Codes: F02D 41/248 using a plurality of learned values
• CPC Class Codes: F16K 37/0083 by measuring valve parameters
• CPC Class Codes: G01R 17/00 Measuring arrangements involving comparison with a reference value, e.g. bridge
• CPC Class Codes: G01R 19/04 Measuring peak values or amplitude or envelope of ac or of pulses
• CPC Class Codes: H01F 7/1805 Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current for holding relay armature in attracted position with reduced energising current H01H47/04; quick energising of electro-dynamic machines H02P9/08; for quickly de-energising of dynamo-electric generators H02P9/123
• CPC Class Codes: H01F 7/1844 Monitoring or fail-safe circuits for relays H01H47/002

Abstract

The subject matter of this specification can be embodied in, among other things, a method for characterizing a fluid injector that includes receiving a collection of waveform data, identifying a pull locus, determining a detection threshold level value, identifying a first subset of the collection of data representative of a selected first electrical waveform of the collection of electrical waveforms, identifying an opening value, identifying a representative closing value, identifying an anchor value, identifying a second subset of the collection of data based on the collection of data, the pull locus, the first subset, and the opening value, identifying a maximum electrical value, identifying an opening locus based the collection of data, the anchor value, and the maximum electrical value, identifying a hold value, and providing characteristics associated with the fluid injector comprising the pull locus, the opening locus, the hold value, the anchor value, and the representative closing value.

Claims

1. A method for characterizing a fluid injector, comprising:

measuring, by an actuator controller, a plurality of electrical waveforms, each waveform corresponding to power consumption of a selected magnitude of electrical excitation provided to an actuator of a fluid injector;

determining, by the actuator controller, a collection of data representative of the plurality of electrical waveforms and based on the measuring of the plurality of electrical waveforms;

identifying, by the actuator controller, a pull locus, based on the collection of data;

determining, by the actuator controller, a detection threshold level value, based on the collection of data;

identifying, by the actuator controller, a first subset of the collection of data representative of a selected first electrical waveform of the plurality of electrical waveforms, based on the detection threshold level value and the collection of data;

identifying, by the actuator controller, a representative opening value, based on the collection of data;

identifying, by the actuator controller, a representative closing value, based on the representative opening value and the collection of data;

identifying, by the actuator controller, an anchor value, based on the collection of data and the first subset;

identifying, by the actuator controller, a second subset of the collection of data, representative of a selected second electrical waveform of the plurality of electrical waveforms, based on the collection of data, the pull locus, the first subset, and the representative opening value;

identifying, by the actuator controller, a maximum electrical value, based on the second subset;

identifying, by the actuator controller, an opening locus based the collection of data, the anchor value, and the maximum electrical value;

identifying, by the actuator controller, a hold value based on the collection of data; and

providing, by the actuator controller, characteristics associated with the fluid injector comprising the pull locus, the opening locus, the hold value, the anchor value, and the representative closing value.

2. The method of claim 1, wherein the plurality of electrical waveforms are current waveforms of the fluid injector, the collection of data is a first collection of fluid injector current measurement values representative of the current waveforms, the pull locus is a second collection of fluid injector current measurement values, the representative opening value is a first fluid injector current measurement value, the anchor value is a second fluid injector current measurement value, the maximum electrical value is a third fluid injector current measurement value, and the opening locus is a third collection of fluid injector current measurement values.

3. The method of claim 1, wherein identifying a pull locus further comprises:

selecting one or more third subsets of the collection of data, each of the selected subsets being representative of a successive pair of the plurality of waveforms, each selected pair representing two magnitude-wise successive electrical waveforms;

for each of the selected third subsets;

determining a differential waveform based on a difference between the pair of waveforms;

determining that the differential waveform includes a zero crossing point; and

identifying and adding a time wise local maxima of the second waveform of the selected pair to a fourth subset of data; and

providing the fourth subset as the pull locus associated with the fluid injector.

4. The method of claim 3, wherein the time wise first local maxima is the effect of a solenoid armature of the fluid injector starting to move relative to a de-energized state of the fluid injector.

5. The method of claim 3, wherein identifying a second subset of the collection of data further comprises:

identifying the last value of the pull locus;

identifying a subset of the collection of data corresponding to the last value; and

providing the identified subset as the second subset.

6. The method of claim 1, wherein identifying the anchor value further comprises:

selecting one or more third subsets of the collection of data, each of the selected subsets being representative of a successive pair of the plurality of waveforms, each selected pair representing two magnitude-wise successive electrical waveforms;

for each of the selected third subsets;

determining a differential waveform based on a difference between the pair of waveforms;

determining that the differential waveform is the first differential waveform to include a zero crossing point; and

providing the zero crossing point as the anchor value associated with the fluid injector.

7. The method of claim 1, wherein identifying the opening locus further comprises:

selecting one or more third subsets of the collection of data, each of the selected subsets being representative of a successive pair of the plurality of waveforms, each selected pair representing two magnitude-wise successive electrical waveforms of the fluid injector;

for each of the selected third subsets;

determining a differential waveform based on a difference between the pair of waveforms;

adding the determined differential waveform to a collection of differential waveform data;

identifying the anchor point within the collection of differential waveform data;

identifying the maximum electrical value within the collection of differential waveform data;

determining a mathematical representation of a line between the anchor value and the maximum electrical value within the collection of differential waveform data;

identifying a collection of values within the collection of differential values that intersect the mathematical representation; and

providing the identified collection of values as the opening locus associated with the fluid injector.

8. The method of claim 1, wherein determining a detection threshold level value further comprises estimating a nominal noise level of one or more of the plurality of electrical waveforms.

9. The method of claim 1, further comprising actuating a solenoid of the fluid injector with a solenoid actuation waveform based on the representative opening value associated with the fluid injector.

10. The method of claim 1, wherein identifying the hold value further comprises:

identifying a first stable waveform of the fluid injector that includes values described by the pull locus and satisfies one or more stabilization criteria;

determining a minimum electrical value based on the first stable waveform; and

providing the minimum electrical value as the hold value associated with the fluid injector.

11. The method of claim 1, further comprising energizing, by the actuator controller, the actuator of the fluid injector with the plurality of electrical excitations.

12. The method of claim 1, further comprising adjusting, by the actuator controller, the selected magnitude of electrical excitation provided to the actuator of the fluid injector.

13. The method of claim 1, further comprising providing, by the actuator controller, an output that is indicative of a behavioral change of the fluid injector.

14. A system for characterizing an injector for a fluid injector, comprising:

a power controller;

a data processing apparatus; and

a computer memory storage device storing instructions executable by a computer device and that upon such execution cause the computer device to perform operations comprising;

measuring, by the power controller, a plurality of electrical waveforms, each waveform corresponding to power consumption of a selected magnitude of power electrical excitation provided to the actuator;

determining a collection of data representative of the plurality of electrical waveforms and based on the measuring of the plurality of electrical waveforms;

identifying a pull locus, based on the collection of data;

determining a detection threshold level value, based on the collection of data;

identifying a first subset of the collection of data representative of a selected first electrical waveform of the plurality of electrical waveforms, based on the detection threshold level value and the collection of data;

identifying a representative opening value, based on the collection of data;

identifying a representative closing value, based on the representative opening value and the collection of data;

identifying an anchor value, based on the collection of data and the first subset;

identifying a second subset of the collection of data, representative of a selected second electrical waveform of the plurality of electrical waveforms, based on the collection of data, the pull locus, the first subset, and the representative opening value;

identifying a maximum electrical value, based on the second subset;

identifying an opening locus based the collection of data, the anchor value, and the maximum electrical value;

identifying a hold value based on the collection of data; and

providing characteristics associated with the fluid injector comprising the pull locus, the opening locus, the hold value, the anchor value, and the representative closing value.

15. The system of claim 14, wherein the plurality of electrical waveforms are current waveforms of the fluid injector, the collection of data is a first collection of fluid injector current measurement values representative of the current waveforms, the pull locus is a second collection of fluid injector current measurement values, the representative opening value is a first fluid injector current measurement value, the anchor value is a second fluid injector current measurement value, the maximum electrical value is a third fluid injector current measurement value, and the opening locus is a third collection of fluid injector current measurement values.

16. The system of claim 14, wherein identifying a pull locus further comprises:

selecting one or more third subsets of the collection of data, each of the selected subsets being representative of a successive pair of the plurality of waveforms, each selected pair representing two magnitude-wise successive electrical waveforms;

for each of the selected third subsets;

determining a differential waveform based on a difference between the pair of waveforms;

determining that the differential waveform includes a zero crossing point; and

identifying and adding a time wise local maxima of the second waveform of the selected pair to a fourth subset of data; and

providing the fourth subset as the pull locus associated with the fluid injector.

17. The system of claim 16, wherein the time wise first local maxima is the effect of a solenoid armature of the fluid injector starting to move relative to a de-energized state of the fluid injector.

18. The system of claim 16, wherein identifying a second subset of the collection of data further comprises:

identifying the last value of the pull locus;

identifying a subset of the collection of data corresponding to the last value; and

providing the identified subset as the second subset.

19. The system of claim 14, wherein identifying the anchor value further comprises:

selecting one or more third subsets of the collection of data, each of the selected subsets being representative of a successive pair of the plurality of waveforms, each selected pair representing two magnitude-wise successive electrical waveforms;

for each of the selected third subsets;

determining a differential waveform based on a difference between the pair of waveforms;

determining that the differential waveform is the first differential waveform to include a zero crossing point; and

provide the zero crossing point as the anchor value associated with the fluid injector.

20. The system of claim 14, wherein identifying the opening locus further comprises:

selecting one or more third subsets of the collection of data, each of the selected subsets being representative of a successive pair of the plurality of waveforms, each selected pair representing two magnitude-wise successive electrical waveforms of the fluid injector;

for each of the selected third subsets;

determining a differential waveform based on a difference between the pair of waveforms;

adding the determined differential waveform to a collection of differential waveform data;

identifying the anchor point within the collection of differential waveform data;

identifying the maximum electrical value within the collection of differential waveform data;

determining a mathematical representation of a line between the anchor value and the maximum electrical value within the collection of differential waveform data;

identifying a collection of values within the collection of differential values that intersect the mathematical representation; and

providing the identified collection of values as the opening locus associated with the fluid injector.

21. The system of claim 14, wherein determining a detection threshold level value further comprises estimating a nominal noise level of one or more of the plurality of electrical waveforms.

22. The system of claim 14, further comprising actuating a solenoid of the fluid injector with a solenoid actuation waveform based on the representative opening value associated with the fluid injector.

23. The system of claim 14, wherein identifying the hold value further comprises:

identifying a first stable waveform of the fluid injector that includes values described by the pull locus and satisfies one or more stabilization criteria;

determining a minimum electrical value based on the first stable waveform; and

providing the minimum electrical value as the hold value associated with the fluid injector.

24. The system of claim 14, further comprising providing a plurality of control signals to an actuator driver configured to energize an actuator of a fluid injector with a plurality of electrical excitations based on the plurality of control signals.

25. The system of claim 14, further comprising adjusting the selected magnitude of electrical excitation provided to the actuator of the fluid injector.

26. The system of claim 14, further comprising providing an output that is indicative of a behavioral change of the fluid injector.