CONTROL SYSTEM FOR ADJUSTING THE TEMPERATURE OF BEARING OIL FOR THE PURPOSE OF MINIMIZING ROTOR VIBRATIONS

Abstract

The invention relates to a control system for reducing rotor vibrations, in particular the variability thereof, in shafting, in particular turbine shafting, in which the temperature of the bearing (6) of the shaft is measured and the oil (8) supplied to the bearing is adjusted to a temperature as is assigned as the output variable in an allocation for minimised rotor vibrations with the measured temperature of the bearing as the input variable. The allocation can, for example, be provided by an initial measurement of the rotor vibrations or by a self-learning system. According to the invention, the variability of the rotor vibrations is restricted.

Claims

1.-8. (canceled)

9. A control system for reducing rotor vibrations, in particular a variability thereof, in a shafting, in particular a turbine shafting, said control system configured to: measure a temperature of a bearing of a shaft, and adjust a temperature of oil supplied to the bearing to a temperature as assigned as an output variable in an allocation for minimized rotor vibrations with the measured temperature of the bearing as the input variable.

10. The control system of claim 9, comprising a valve configured to adjust the temperature of the oil supplied to the bearing, with the valve and the bearing being part of an oil circuit.

11. The control system of claim 10, further comprising a mixing valve configured to combine an output of an oil cooler and a bypass of the oil circuit, with the bypass bypassing the oil cooler and connected to the mixing valve, said valve being disposed in the bypass.

12. The control system of claim 10, further comprising for initial assignment with different temperatures of the bearing, measuring the rotor vibrations, calculating the respective oil temperatures of the bearing for minimizing the rotor vibrations, storing the respective oil temperatures of the bearing as input variables, and storing the associated calculated bearing oil temperatures as output variables in the assignment.

13. The control system of claim 12, further comprising: obtaining empirical values from an operating history of the shafting, and storing the empirical values in the assignment as output variables.

14. The control system of claim 12, wherein the assignment is provided by a self-learning system.

15. The control system of claim 12, wherein the assignment is provided by a neural network.

16. The control system of claim 12, wherein the assignment is provided by a signal processor.

17. The control system of claim 9, wherein the bearing is a generator bearing.

18. A method for reducing rotor vibrations, in particular a variability thereof, in a shafting, in particular a turbine shafting, said method comprising: measuring a temperature of a bearing of a shaft, and adjusting a temperature of oil supplied to the bearing to a temperature as assigned as an output variable in an allocation for minimized rotor vibrations with the measured temperature of the bearing as the input variable.

19. The method of claim 18, wherein the temperature of the oil supplied to the bearing is adjusted by a valve, with the valve and the bearing being part of an oil circuit.

20. The method of claim 19, further comprising combining an output of an oil cooler and a bypass of the oil circuit, with the bypass bypassing the oil cooler and connected to the mixing valve and the valve being disposed in the bypass.

21. The method of claim 19, further comprising for initial assignment with different temperatures of the bearing, measuring the rotor vibrations, calculating the respective oil temperatures of the bearing for minimizing the rotor vibrations, storing the respective oil temperatures of the bearing as input variables, and storing the associated calculated bearing oil temperatures as output variables in the assignment.

22. The method of claim 21, further comprising: obtaining empirical values from an operating history of the shafting, and storing the empirical values in the assignment as output variables.

23. The method of claim 21, wherein the assignment is provided by a self-learning system.

24. The method of claim 21, wherein the assignment is provided by a neural network.

25. The method of claim 21, wherein the assignment is provided by a signal processor.

26. An oil circuit, comprising: a bearing for support of a shaft; a bearing oil tank; a pump supply oil from the bearing oil tank to the bearing; an oil cooler; a bypass bypassing the air cooler and having a valve configured to adjust a temperature of the oil (8) supplied to the bearing; a mixing valve fluidly connected to the oil cooler and the bypass to combine an output of the oil cooler and the bypass; and a control system for reducing rotor vibrations, said control system configured to measure the temperature of the bearing, and to adjust a temperature of oil supplied to the bearing to a temperature as assigned as an output variable in an allocation for minimized rotor vibrations with the measured temperature of the bearing as the input variable.

27. The oil circuit of claim 26, wherein the bearing is a generator bearing.

Description

[0011] The invention is explained in more detail below as an exemplary embodiment using figures to the extent required for understanding. In the drawings:

[0012] FIG. 1 shows the temperature dependency of the dynamic viscosity etha for typical viscosity grades.

[0013] FIG. 2 shows the dynamic behavior of a single-shaft system for different lubricating oil supply temperatures, and

[0014] FIG. 3 shows a temperature-controlled lubricating oil circuit which realizes the invention

[0015] In the figures, like reference characters denote like elements.

[0016] FIG. 1 shows a graphic representation of the dynamic viscosity equation after rust for the viscosity grades ISOVG 32 (lower line) and ISOVG 46 (upper line).

[0017] FIG. 2 shows the calculated dynamic behavior of a single-shaft system with a lubricating oil of the viscosity grade ISOVG 32, in the left diagram with a lubricating oil supply temperature of 46 C. and in the right diagram with a lubricating oil supply temperature of 56 C.

[0018] The oil circuit shown in FIG. 3 comprises a bearing 6, a bearing oil tank 4, a pump 5, an oil cooler 3, a bypass, having a valve 2, to the oil cooler and a mixing valve 1 which combines the output of the oil cooler and the bypass. The temperature of the bearing 6, which acts as a heat source, is measured by means of a temperature sensor 7.

[0019] The temperature 8 of the oil supplied to the bearing is adjusted with the aid of the valve 2.

[0020] The oil supplied to the bearing is adjusted to a temperature level 8 as is stored as the output variable in an allocation table for minimized rotor vibrations with the measured temperature of the bearing as the input variable.

[0021] The present invention has been explained in detail for illustration purposes on the basis of specific exemplary embodiments. Here elements of the individual exemplary embodiments can also be combined with one another. The invention should therefore not be restricted to individual exemplary embodiments but should only be restricted by the appended claims.

LIST OF REFERENCE CHARACTERS

[0022] 13-way mixing valve [0023] 2control valve, cooler bypass [0024] 3cooler, oil cooler [0025] 4tank, bearing oil tank [0026] 5pump, lubricating oil pump [0027] 6bearing, heat source [0028] 7sensor bearing temperature [0029] 8lubricating oil supply temperature, bearing oil temperature