METHOD AND SYSTEMS FOR OPERATING A WIND TURBINE

• US 20110137474A1
• Filed: 12/16/2009
• Published: 06/09/2011
• Est. Priority Date: 12/16/2009
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (General Electric Company)
• Original Assignee: General Electric Company
• Inventors: Larsen, Einar Vaughn, Klodowski, Anthony Michael, Barker, Sidney Allen
• Granted Patent: US 8,046,109 B2
• Time in Patent Office: Days
• US Class Current: 700/287
• CPC Class Codes: F03D 7/0284 in relation to the state of the electric grid
• CPC Class Codes: F05B 2270/10711 applying a low voltage ride through method
• CPC Class Codes: F05B 2270/335 Output power or torque
• CPC Class Codes: F05B 2270/337 Electrical grid status parameters, e.g. voltage, frequency or power demand
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/44 with means for ensuring correct phase sequence
• CPC Class Codes: H02J 3/48 Controlling the sharing of the in-phase component
• CPC Class Codes: H02J 3/50 Controlling the sharing of the out-of-phase component
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects

Abstract

A method for controlling operation of a wind turbine included within a power generation and delivery system is described. The method includes measuring at least one operating condition of the power generation and delivery system. The method also includes transmitting, to a power limiter system, an operating condition feedback signal that corresponds to the operating condition. The method also includes analyzing the operating condition feedback signal to identify an occurrence of a grid contingency event and generating a real current command signal corresponding to an occurrence of a grid contingency event. The method also includes transmitting the real current command signal to a controller and applying the real current command signal to power converter performance to facilitate reducing pole-slipping. The method also includes storing, in a memory, at least one variable corresponding to the operating condition upon the occurrence of a grid contingency event.

Claims

1. A method for controlling operation of a wind turbine included within a power generation and delivery system, the wind turbine comprising a rotor comprising a plurality of rotor blades, an electrical generator, a power converter, and a controller, said method comprising:

measuring at least one operating condition of the power generation and delivery system, the operating condition dependent upon an occurrence of a grid contingency event;

transmitting, to a power limiter system, an operating condition feedback signal that corresponds to the operating condition;

analyzing, using the power limiter system, the operating condition feedback signal to identify an occurrence of a grid contingency event;

generating, using the power limiter system, a real current command signal corresponding to an occurrence of a grid contingency event;

transmitting the real current command signal to the controller;

applying the real current command signal to power converter performance to facilitate reducing pole-slipping; and

,

storing, in a memory, at least one variable corresponding to the operating condition upon the occurrence of a grid contingency event to facilitate determining whether power generation and delivery system is operating properly.

2. A method in accordance with claim 1, wherein measuring at least one operating condition includes measuring at least one of a phase locked loop (PLL) error and a terminal grid voltage.

3. A method in accordance with claim 2, further comprising:

generating a phase error signal that corresponds to a sustained PLL error; and

,

transmitting the phase error signal to the power limiter system.

4. A method in accordance with claim 2, wherein generating the real current command signal further comprises generating a real current command signal that corresponds to a grid contingency event when the terminal grid voltage is reduced below a predefined level.

5. A method in accordance with claim 2, wherein generating the real current command signal further comprises generating a real current command signal that corresponds to a grid contingency event when the phase error signal is above a predefined level.

6. A method in accordance with claim 1, wherein applying the real current command signal to power converter performance comprises rapidly reducing real current output by the power converter upon receipt of a real current command signal that corresponds to a grid contingency event.

7. A method in accordance with claim 1, wherein applying the real current command signal to power converter performance comprises slowly increasing real current output by the power converter upon receipt of a real current command signal that indicates a recovery from the grid contingency event.

8. A method in accordance with claim 2, further comprising:

transmitting the terminal grid voltage feedback signal to a voltage regulator; and

,

generating a reactive current command signal at the voltage regulator that increases the reactive current output by the power converter when the terminal grid voltage feedback signal indicates a grid contingency event.

9. A method in accordance with claim 1, further comprising:

receiving, at a higher-level control, a wind farm operating condition;

generating a curtailment signal based at least partially on the wind farm operating condition; and

,

transmitting the curtailment signal to the power limiter system.

10. A method in accordance with claim 9, wherein receiving a wind farm operating condition comprises receiving a voltage measurement at a point of common coupling for a plurality of wind turbines within a wind farm.

11. A grid-dependent power limiter system for reducing pole-slipping, said system comprising:

a power limiter configured to;

receive at least one of a phase locked loop (PLL) error signal and a terminal grid voltage feedback signal; and

,

generate a power command signal based on at least one of the PLL error signal and the terminal grid voltage feedback signal;

a power regulator coupled to said power limiter, said power regulator configured to;

receive the power command signal;

generate a real current command signal based at least partially on the power command signal; and

,

transmit the real current command signal to a controller; and

,

a memory configured to store at least one variable that corresponds to an operating condition measured upon an occurrence of a grid contingency event.

12. A system in accordance with claim 11, further comprising a voltage regulator configured to:

receive the terminal grid voltage feedback signal;

generate a reactive current command signal based at least partially on the terminal grid voltage feedback signal; and

,

transmit the reactive current command signal to the controller.

13. A system in accordance with claim 11, wherein the power limiter is configured to generate a power command signal that corresponds to a grid contingency event when the terminal grid voltage feedback signal indicates that the terminal grid voltage is below a predefined level.

14. A system in accordance with claim 11, wherein the power limiter is configured to generate a power command signal that corresponds to a grid contingency event when the PLL error signal is above a predefined level.

15. A system in accordance with claim 11, wherein the power regulator is configured to generate a real current command signal that directs a power converter to rapidly reduce a real current output by the power converter after identification of a grid contingency event.

16. A system in accordance with claim 15, wherein the power regulator is configured to generate a real current command signal that directs the power converter to slowly increase the real current output by the power converter after a recovery from a grid contingency event.

17. A power generation and distribution system comprising:

an electric generator;

a power conversion assembly coupled to said electric generator and a utility grid, said power conversion assembly configured to receive power generated by said electric generator and convert the power received to a power suitable for transmission over the utility grid; and

,

a power limiter system communicatively coupled to said power conversion assembly and configured to provide a real current control signal to said power conversion assembly, the real current control signal based at least partially on at least one measured indicator of a grid contingency event, said power limiter system comprising a memory configured to store at least one variable that corresponds to the measured indicator of a grid contingency event upon an occurrence of the grid contingency event.

18. A system in accordance with claim 17, wherein said power limiter system receives at least one of a phase locked loop (PLL) error signal and a terminal grid voltage feedback signal, said power limiter system configured to identify an occurrence of a grid contingency event based at least partially on the at least one of a PLL error signal and a terminal grid voltage feedback signal.

19. A system in accordance with claim 17, wherein said power conversion assembly is configured to reduce a real current output by said power conversion assembly, to facilitate reducing pole-slipping, upon receipt of a real current control signal corresponding to a grid contingency event.

20. A system in accordance with claim 17, wherein said power conversion assembly is further configured to slowly increase a real current output by said power conversion assembly upon receipt of a real current control signal corresponding to recovery from a grid contingency event.