Actuator with deadbeat control

Patent metadata

Field	Value
Publication number	US-9726100-B2
Application number	US-201514645391-A
Country	US
Kind code	B2
Filing date	Mar 11, 2015
Priority date	Mar 20, 2014
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

An electromagnetic actuation system includes an actuator having an electrical coil, a magnetic core, and an armature. The system further includes a controllable bi-directional drive circuit for selectively driving current through the electrical coil in either of two directions. The control module provides an actuator command to the drive circuit effective to drive current through the electrical coil in a first direction to actuate the armature and in a second direction subsequent to armature actuation to oppose residual flux within the actuator. The control module includes a residual flux feedback control module configured to adapt the actuator command to converge residual flux within the actuator to a preferred flux level.

First claim

The invention claimed is:

1. An electromagnetic actuation system, comprising:
an actuator comprising an electrical coil, a magnetic core, and an armature;
a controllable bi-directional drive circuit for selectively driving current through the electrical coil in either of two directions; and
a control module providing an actuator command to the drive circuit effective to drive current through the electrical coil in a first direction to actuate the armature and in a second direction subsequent to armature actuation to oppose residual flux within the actuator, said control module comprising a residual flux feedback control module configured to adapt said actuator command to converge residual flux within the actuator to a preferred flux level.

2. The electromagnetic actuation system of claim 1 , wherein said preferred flux level comprises a zero flux level.

3. The electromagnetic actuation system of claim 1 , wherein said preferred flux level comprises a non-zero flux level having a magnitude that is less than the magnitude of a level of residual flux passively attained within the electrical coil at zero current.

4. The electromagnetic actuation system of claim 1 , wherein said residual flux feedback control module comprises an electrical coil current feedback loop configured to adapt said actuator command to converge electrical coil current to a desired electrical coil current.

5. The electromagnetic actuation system of claim 4 , wherein said residual flux feedback control module comprises a search coil mutually magnetically coupled to the electrical coil configured to sense time rate of change of the residual flux within the actuator.

6. The electromagnetic actuation system of claim 1 , wherein said residual flux feedback control module comprises a search coil mutually magnetically coupled to the electrical coil configured to sense time rate of change of the residual flux within the actuator.

7. The electromagnetic actuation system of claim 1 , wherein said residual flux feedback control module comprises a magnetoresistive sensor configured to sense the residual flux within the actuator.

8. The electromagnetic actuation system of claim 1 , wherein said residual flux feedback control module comprises a hall effect sensor configured to sense the residual flux within the actuator.

9. The electromagnetic actuation system of claim 1 , wherein said residual flux feedback control module comprises a deadbeat control module.

10. A method for controlling an electromagnetic actuator, comprising:
driving current though an electrical coil of the actuator in a first direction when an actuation is desired; and,
when the actuation is not desired driving current through the electrical coil in a second direction sufficient to reduce residual flux within the actuator below a level passively attained within the actuator at zero coil current, wherein driving current through the electrical coil in the second direction comprises adapting the current through the electrical coil in the second direction based upon a residual flux feedback to converge residual flux within the actuator to a preferred flux level.

11. The method for controlling the electromagnetic actuator of claim 10 , further comprising:
adapting the current through the electrical coil in the second direction based upon an electrical coil current feedback to converge electrical coil current to a desired electrical coil current.

12. The method for controlling the electromagnetic actuator of claim 10 , wherein said residual flux feedback comprises a voltage induced within a search coil mutually magnetically coupled to the electrical coil.

13. The method for controlling the electromagnetic actuator of claim 10 , wherein adapting the current through the electrical coil in the second direction based upon a residual flux feedback comprises inputting said residual flux feedback into a deadbeat control module.

14. A system for controlling actuation of a fuel injector, comprising:
a fuel injector comprising an electrical coil, a magnetic core, and an armature;
a controllable bi-directional drive circuit responsive to a current command for driving current through the electrical coil in a first direction to actuate the armature, in a second direction subsequent to armature actuation for a predetermined duration, and thereafter to zero; and
a control module configured to determine a residual flux in the fuel injector after the current through the electrical coil is driven to zero and adapt the current command to control the predetermined duration based on the residual flux.

15. The system for controlling actuation of the fuel injector of claim 14 , wherein said control module is further configured to determine the current through the electrical coil and adapt the current command based on the current through the electrical coil.

16. The system for controlling actuation of the fuel injector of claim 14 , further comprising a search coil mutually magnetically coupled to the electrical coil, said control module further configured to determine a time rate of change of the residual flux within the fuel injector based on the search coil, wherein the residual flux in the fuel injector after the current through the electrical coil is driven to zero is determined based on the time rate of change of the residual flux within the fuel injector.

17. The system for controlling actuation of the fuel injector of claim 14 , further comprising a magnetoresistive sensor disposed within a flux path within the fuel injector, said control module further configured to determine the residual flux within the fuel injector based on the magnetoresistive sensor.

18. The system for controlling actuation of the fuel injector of claim 14 , further comprising a hall effect sensor disposed within a flux path within the fuel injector, said control module further configured to determine the residual flux within the fuel injector based on the hall effect sensor.

19. The system for controlling actuation of the fuel injector of claim 14 , wherein said control module comprises a deadbeat control module.

20. The system for controlling actuation of the fuel injector of claim 16 , wherein said control module comprises a deadbeat control module.

Assignees

• Gm Global Technoloby Operations Llc
• Gm Global Tech Operations Llc

Inventors

• Gopalakrishnan Suresh
• Namuduri Chandra S
• Nehl Thomas Wolfgang
• Omekanda Avoki M

Classifications

• F02M51/061

  using electromagnetic operating means · CPC title

• F02D2041/141

  using a feed-forward control element · CPC title

• H03K17/64

  having inductive loads · CPC title

• F02D2041/2044

  using pre-magnetisation or post-magnetisation of the coils · CPC title

• F02D41/20 Primary

  Output circuits, e.g. for controlling currents in command coils · CPC title