Method and power converter unit for operating a generator

Patent metadata

Field	Value
Publication number	US-9917544-B2
Application number	US-201615043518-A
Country	US
Kind code	B2
Filing date	Feb 13, 2016
Priority date	Feb 13, 2016
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

A method and power converter unit for operating a generator includes a rotatable shaft operably coupled with a source of rotational force, a rotor mounted to the rotatable shaft and having at least one rotor pole defining a rotatable direct axis, a stator encircling the rotor and having a set of stator windings, and a power output electrically coupled with the set of stator windings and operable in a power generating mode and a power absorption mode

First claim

What is claimed is:

1. An electric machine assembly comprising:
a rotatable shaft configured to operably couple with a source of rotational force;
a rotor mounted to the rotatable shaft and having at least one rotor pole defining a rotatable direct axis;
a stator about the rotor and having a set of stator windings; and
a power converter unit electrically coupled with the set of stator windings and operable in a power generating mode and a power absorption mode;
wherein the power converter unit in the power generating mode is configured to convert power generated in the set of stator windings to supply to a power distribution network; and
wherein the power converter unit in the power absorption mode is configured to convert excess power from the power distribution network to a set of absorption power signals in-phase with the rotatable direct axis, and to supply the set of absorption power signals to the set of stator windings and reduces torque experienced by the electric machine when supplied to the set of stator windings in the electric machine.

2. The electric machine assembly of claim 1 , wherein the power converter unit further comprises at least one of a power converter or current regulator.

3. The electric machine assembly of claim 2 , wherein the at least one of a power converter or current regulator comprises a transistor bridge selectively operable to convert a first power to a second power.

4. The electric machine assembly of claim 3 , further comprising a sensor configured to determine a rotatable position of the rotatable shaft.

5. The electric machine assembly of claim 4 , wherein the at least one of a power converter or current regulator is configured to respectively convert or regulate excess power of the power distribution network to the set of absorption power signals based on a position of the rotatable shaft.

6. The electric machine assembly of claim 1 , further comprising a sensor configured to determine current power characteristics of the power distribution network.

7. The electric machine assembly of claim 1 , further comprising a stator winding heat dissipation system.

8. A power converter unit for an electric machine comprising:
a first input/output connection configured to operably couple with a set of stator windings of an electric machine;
a second input/output connection configured to operably couple with a power distribution network; and
a power-converting circuit operable in a power supplying mode or in a power dissipating mode;
wherein the power-converting circuit in the power supplying mode is configured to convert a first power received at the first input/output connection from the electric machine to a desired power supply for the power distribution network and to supply the converted first power to the second input/output connection;
wherein the power-converting circuit in the power dissipating mode is configured to convert a second power in excess of desired power characteristics received at the second input/output connection from the power distribution network to a converted second power and to supply the converted second power to the first input/output connection; and
wherein the converted second power is in phase with a rotatable direct axis of the electric machine and reduces torque experienced by the electric machine when supplied to a set of stator windings in the electric machine.

9. The power converter unit of claim 8 , further comprising a controller module communicatively coupled with the power converting circuit and configured to operate the power converting circuit in the power supplying mode or the power dissipating mode.

10. The power converter unit of claim 9 , wherein the power converter unit comprises at least one of an active-rectifier power converter or a transistor bridge, and wherein the controller module is communicatively coupled with the at least one of an active-rectifier power converter or a transistor bridge.

11. The power converter unit of claim 8 , further comprising a sensor configured to determine current power characteristics of the power distribution network.

12. A method of operating an electric machine, comprising:
determining, in a control module, whether a current power level for a power distribution system coupled with an input/output of the electric machine exceeds a power level threshold value:
in response to the current power level not exceeding the power level threshold value, operating the electric machine in a power generation mode wherein rotation of a rotor relative to a set of stator windings of the electric machine supplies power from the electric machine to the power distribution system; and
in response to the current power level exceeding the power level threshold value, operating the electric machine in a power absorption mode wherein power in the power distribution system is received by a power converter, converted by the power converter to a set of absorption power signals in-phase with a rotating magnetic field of a rotating rotor in the electric machine, and wherein the set of absorption power signals is supplied from the power converter to the set of stator windings of the electric machine,
whereby to dissipate heat in the set of stator windings such that torque experienced by the rotating rotor is reduced.

13. The method of claim 12 , wherein the operating the electric machine in the power absorption mode comprises eliminating excess torque experienced by the rotating rotor.

14. The method of claim 12 , further comprising sensing, by a power sensor, the current power level for the power distribution system.

15. The method of claim 12 , further comprising sensing, by a sensor, a position of the rotating rotor.

16. The method of claim 15 , wherein the set of absorption power signals is based on the position of the rotating rotor.

17. The method of claim 16 , wherein the set of absorption power signals is configured to generate a rotating magnetic field in the set of stator windings in-phase with a magnetic field of the rotating rotor.

18. The method of claim 12 , wherein the operating the electric machine in the power absorption mode comprises controllably dissipating at least a portion of the set of absorption power signals, as heat, in the set of stator windings.

19. The method of claim 12 , further comprising estimating, by the control module, a position of the rotating rotor.

20. The method of claim 19 , wherein the set of absorption power signals is based on the rotating rotor position.

Assignees

• Ge Aviation Systems Llc

Inventors

• Buffenbarger Ryan Lee
• Jia Xiaochuan
• Gataric Slobodan

Classifications

• H02K9/005

  Electricity · mapped topic

• H02K11/33

  Drive circuits, e.g. power electronics (H02K11/38 takes precedence) · CPC title

• H02K11/21

  Devices for sensing speed or position, or actuated thereby (specially adapted for machines having non-mechanical commutating devices H02K29/06, H02K29/14) · CPC title

• H02P29/20 Primary

  for controlling one motor used for different sequential operations · CPC title

• H02K19/38 Primary

  Structural association of synchronous generators with exciting machines · CPC title