Method for starting up a wind energy plant after an operation stoppage and wind energy plant which can execute the method

1. A method for starting up a wind energy plant after an operation stoppage, comprising the steps of:

providing a wind energy plant having a gearbox in the drive train and an operation management which can control at least one operational variable B significant for the strain of the gearbox of the wind energy plant to a desired value B S ,

limiting the desired value B S by a maximum value B Max , which is preset depending on a measured temperature of a gearbox component or of a lubricant for the gearbox.

2. A method according to claim 1 , characterised in that one of the operational variables B significant for the strain of the gearbox is the electric power generated by the wind energy plant.

3. A method according to claim 1 , characterised in that one of the operational variables B significant for the strain of the gearbox is a torque in the drive train of the wind energy plant.

4. A method according to claim 1 , characterised in that the temperature T of the lubricant in an oil pan or an oil line of the gearbox is measured.

5. A method according to claim 1 , characterised in that the start-up is ended when the measured temperature T corresponds to a certain operation temperature.

6. A method according to claim 1 , characterised in that the maximum value B Max is increased after an operation stoppage, until it reaches a rated value B N of the wind energy plant at a certain temperature T 2 .

7. A method according to claim 1 , characterised in that the maximum value B Max has an initial value B F when the wind energy plant is started up.

8. A method according to claim 1 , characterised in that the maximum value B Max is kept constant up to a presettable temperature T 1 after starting up the wind energy plant.

9. A method according to claim 1 , characterised in that the maximum value B Max is preset to be proportional to the temperature T in a period.

10. A method according to claim 9 , characterised in that the maximum value B Max is preset to be proportional to the temperature T between the temperatures T 1 and T 2 .

11. A method according to claim 1 , characterised in that the wind energy plant is started up only when a minimum value B min of the operational variable B significant for the strain of the gearbox is to be expected.

12. A method according to claim 1 , characterised in that it is not fallen below a minimum value B min of the operational variable B significant for the strain of the gearbox when the wind energy plant is started up.

13. A wind energy plant with a gearbox in the drive train, at least one temperature sensor for measuring a temperature T of a gearbox component or of a lubricant for the gearbox and an operation management, which can control at least one operational variable B of the wind energy plant significant for the strain of the gearbox to a desired value B S , wherein the operation management has an equipment for establishing a maximum value B Max depending on a temperature T established by the at least one temperature sensor, and wherein the operation management can preset the maximum value B Max for the limitation of the desired value B S .

14. A wind energy plant according to claim 13 , characterised in that one of the operational variables B significant for the strain of the gearbox is the electric power generated by the wind energy plant.

15. A wind energy plant according to claim 13 , characterised in that one of the operational variables B significant for the strain of the gearbox is a torque in the drive train of the wind energy plant.

16. A wind energy plant according to claim 13 , characterised in that the at least one temperature sensor is arranged in an oil pan or an oil line of the gearbox.

17. A wind energy plant according to claim 13 , characterised in that the operation management can end the start-up when the measured temperature T corresponds to a certain operation temperature.

18. A wind energy plant according to claim 13 , characterised in that the equipment for establishing the maximum value B Max can increase the maximum value B Max after an operation stoppage, until it reaches a rated value B N of the wind energy plant at a certain temperature T 2 .

19. A wind energy plant according to claim 13 , characterised in that the equipment for establishing a maximum value B Max can preset an initial value B F when the wind energy plant is started up.

20. A wind energy plant according to claim 13 , characterised in that the equipment for establishing a maximum value B Max can keep the maximum value B Max constant up to a presettable temperature T 1 after starting up the wind energy plant.

21. A wind energy plant according to claim 13 , characterised in that the equipment for establishing a maximum value B Max can preset the maximum value B Max to be proportional to the temperature T in a period.

22. A wind energy plant according to claim 21 , characterised in that the equipment for establishing a maximum value B Max can preset the maximum value B Max to be proportional to the temperature T between the temperatures T 1 and T 2 .

23. A wind energy plant according to claim 13 , characterised in that the operation management can start up the wind energy plant selectively only when a minimum value B min of the operational variable B significant for the strain of the gearbox is achievable.

24. A wind energy plant according to claim 13 , characterised in that the operation management can control the wind energy plant when starting up such that it is not fallen below a minimum value B min of the operational variable B significant for the strain of the gearbox.

25. The wind energy plant of claim 13 wherein the maximum value B Max is preset depending on both the measured temperature of the gearbox component and of the lubricant for the gearbox.