Method for operating a wind energy plant

• US 20040207206A1
• Filed: 05/07/2004
• Published: 10/21/2004
• Est. Priority Date: 04/20/2001
• Status: Active Grant

• Current Assignee: Aloys Wobben
• Original Assignee: Aloys Wobben
• Inventors: Wobben, Aloys
• Granted Patent: US 7,462,946 B2
• Time in Patent Office: Days
• US Class Current: 290/44
• CPC Class Codes: F03D 7/0284 in relation to the state of the electric grid
• CPC Class Codes: F03D 7/042 by means of an electrical or electronic controller
• CPC Class Codes: F03D 9/255 connected to electrical distribution networks; Arrangements therefor
• CPC Class Codes: F05B 2270/1033 Power (if explicitly mentioned)
• CPC Class Codes: F05B 2270/1071 in particular sudden load loss
• 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: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

The present invention relates to a method for operating a wind turbine with a generator, drivable by a rotor, for supplying electrical power to an electrical load, in particular an electric grid. In order to compensate for fluctuations in the grid as far as possible, the system of the kind initially specified is developed in such a way that the power delivered to the load by the generator is regulated in response to a current outputted to the load.

Claims

1. Method for operating a wind turbine with an electrical generator, drivable by a rotor, for supplying electrical power to an electrical load, in particular an electric grid, characterized in that the power delivered by the generator (12) to the load (6) is regulated in response to a current that is outputted to the load (6).

2. Method according to claim 1,

characterized in that the power outputted by the generator (12) to the load is regulated in response to the amount of current outputted to the load.

3. Method according to claim 1 or 2,

characterized in that the current is an alternating current with a predefinable frequency.

4. Method according to claim 3,

characterized in that the predefinable frequency is substantially equal to the grid frequency.

5. Method according to one of the preceding claims,

characterized in that the outputted power does not exceed a predefinable amount, has a predefinable phase position and/or includes a predefinable proportion of reactive current.

6. Method according to claim 5,

characterized in that, in multiphase systems, the amount, phase position and/or the proportion of reactive current for each phase do not exceed the predefinable value.

7. Method according to claim 5 or 6,

characterized in that for each phase a value independent of the other phases can be predefined.

8. Method according to one of the preceding claims, characterized in that the current is limited for every phase affected by a short circuit to the momentary value at the moment the short circuit occurs.

9. Wind turbine, in particular for implementing a method according to the preceding claims, comprising a rotor and an electrical generator coupled to the rotor for outputting electrical power to an electric grid, characterized by a regulating device with a current sensor for sensing the electrical current outputted to a grid (6), such that the power delivered by the generator to the grid (6) can be regulated in response to the current that is received by the current sensor.

10. Wind turbine according to claim 9,

characterized in that the regulation device has a microprocessor (20).

11. Wind turbine according to one of claims 9 or 10,

characterized by an external control input (22) for transferring data to the regulating device.

12. Wind turbine according to one of the claims 9 to 11,

characterized by a device for detecting a short circuit in the grid.

13. Wind turbine according to claim 12,

characterized by a voltage sensing device for detecting the voltage of at least one phase in the grid.

14. Wind turbine according to claim 12 or 13,

characterized by a phase monitor for detecting the phase position of the currents and/or voltages of at least one phase in the grid.

15. Wind turbine, in particular with one of the features according to one of the preceding claims, with a generator for supplying electrical power to an electric grid, characterized in that the wind turbine remains connected to the grid when a short circuit or similar disruption occurs, for example when the voltage reaches a value that deviates by more than 20% and preferably by more than 40% from the reference value.

16. Wind turbine, in particular according to one of the preceding claims, with a generator for supplying electrical power to an electric grid, and an external control input with transfer of data to a device for regulating the wind turbine, wherein control signals are received via the external control input from the grid operator or from the energy supplier operating the grid, and in response to said control signals from the grid operator the wind turbine is controlled in response to the needs of the grid operator and hence that electrical power, for example the non-reactive power, the wind power, the current position, the voltage position or the phase position, is fed into the grid in a form as required by the grid operator.