METHOD AND ARRANGEMENT FOR CONTROLLING THE LUBRICATION OF A GEAR SYSTEM

• US 20130074628A1
• Filed: 09/21/2012
• Published: 03/28/2013
• Est. Priority Date: 09/22/2011
• Status: Active Grant

• Current Assignee: Moventas Gears Oy
• Original Assignee: Moventas Gears Oy
• Inventors: UUSITALO, Kari, Elfstrm, Jukka
• Granted Patent: US 9,353,849 B2
• Time in Patent Office: Days
• US Class Current: 74/467
• CPC Class Codes: F16H 57/0435 Pressure control for supplying lubricant; Circuits or valves therefor
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y10T 74/19991 Lubrication

Abstract

A gear lubrication arrangement comprises a lubrication pump for circulating lubrication fluid. A power source coupled to the lubrication pump drives the lubrication pump, and a controller controls an output power of the lubrication pump. The gear lubrication arrangement comprises a pressure sensor disposed down-stream of the lubrication pump The pressure sensor is configured to measure a pressure of the lubrication fluid and to produce a pressure indication signal representative thereof. The controller is arranged to vary the output power of the lubrication pump at least partly on the basis of the pressure indication signal.

Claims

1. A gear lubrication arrangement for providing lubrication to a gear of a wind turbine, comprising:

a lubrication pump for circulating lubrication fluid in the gear of the wind turbine,

a power source coupled to the lubrication pump for driving the lubrication pump, and

a controller coupled to at least one of the lubrication pump and the power source, for controlling an output power of the lubrication pump,

characterized in that;

the gear lubrication arrangement comprises a pressure sensor disposed downstream of the lubrication pump in respect of lubrication fluid pumped by the lubrication pump,

the pressure sensor is configured to measure a pressure of the lubrication fluid and to produce a pressure indication signal representative thereof, and

the controller is arranged to vary the output power of the lubrication pump at least partly on the basis of the pressure indication signal.

2. A gear lubrication arrangement according to claim 1, characterized in that the controller is arranged to vary the output power of the lubrication pump to drive the measured pressure of the lubrication fluid towards a target pressure.

3. A gear lubrication arrangement according to claim 2, characterized in that the controller comprises a proportional and integrative regulator, and a difference between the pressure indication signal and a target value of the pressure indication signal represents an input quantity of the proportional and integrative regulator.

4. A gear lubrication arrangement according to claim 1, characterized in that the controller is arranged to compensate for changes in the measured pressure of the lubrication fluid, by increasing the output power of the lubrication pump as a response to the measured pressure being lower than a first predetermined value, and by decreasing the output power of the lubrication pump as a response to the measured pressure being higher than a second predetermined value.

5. A gear lubrication arrangement according to claim 1, characterized in that the controller is arranged to select the output power of the lubrication pump from a set of at least three discrete values.

6. A gear lubrication arrangement according to claim 1, characterized in that the controller is arranged to vary the output power of the lubrication pump continuously.

7. A gear lubrication arrangement according to claim 1, characterized in that:

the gear lubrication arrangement comprises a temperature sensor configured to measure a temperature of the lubrication fluid and to produce a temperature indication signal representative thereof, and

the controller is arranged to vary the output power of the lubrication pump at least partly on the basis of the temperature indication signal.

8. A gear lubrication arrangement according to claim 1, characterized in that:

the gear lubrication arrangement comprises a signalling output for transmitting information to a remote monitoring location, and

the controller is configured to send to said signalling output information indicative of which output power it has selected for the lubrication pump.

9. A gear lubrication arrangement according to claim 1, characterized in that:

the power source is an electric motor, and

the controller comprises a frequency converter coupled to deliver a driving electric signal to said electric motor.

10. A gear unit of a wind turbine, comprising:

a first shaft (102) and a second shaft (103) for connecting to an external mechanical system,

at least one gear stage (104) located between the first and second shafts (102, 103),

bearings (105) supporting said first and second shafts (102, 103), and

a gear lubrication arrangement according to claim 1 for providing lubrication to said gear stage (104) and said bearings (105).

16. A gear lubrication arrangement according claim 2, characterized in that the controller is arranged to compensate for changes in the measured pressure of the lubrication fluid, by increasing the output power of the lubrication pump as a response to the measured pressure being lower than a first predetermined value, and by decreasing the output power of the lubrication pump as a response to the measured pressure being higher than a second predetermined value.

17. A gear lubrication arrangement according claim 3, characterized in that the controller is arranged to compensate for changes in the measured pressure of the lubrication fluid, by increasing the output power of the lubrication pump as a response to the measured pressure being lower than a first predetermined value, and by decreasing the output power of the lubrication pump as a response to the measured pressure being higher than a second predetermined value.

18. A gear lubrication arrangement according to claim 2, characterized in that the controller is arranged to select the output power of the lubrication pump from a set of at least three discrete values.

19. A gear lubrication arrangement according to claim 3, characterized in that the controller is arranged to select the output power of the lubrication pump from a set of at least three discrete values.

20. A gear lubrication arrangement according to claim 4, characterized in that the controller is arranged to select the output power of the lubrication pump from a set of at least three discrete values.

11. A method for providing lubrication to a gear of a wind turbine, comprising:

circulating lubrication fluid to the gear with a selected pumping power,

measuring a pressure of the lubrication fluid downstream of a lubrication pump that produces said pumping power, and

varying the selected pumping power at least partly on the basis of the pressure indication signal.

12. A method according to claim 11, comprising:

driving the measured pressure of the lubrication fluid towards a target pressure by varying the selected pumping power.

13. A method according to claim 11, comprising:

measuring a temperature of the lubrication fluid and producing a temperature indication signal representative thereof, and

varying the selected pumping power at least partly on the basis of the temperature indication signal.

14. A method according to claim 13, comprising:

as a response to a temperature indication signal indicative of the lubrication fluid being colder than a predetermined threshold, selecting a second target pressure for the lubrication fluid that is lower than a first target pressure that is selected for the lubrication fluid at temperatures that are higher than said predetermined threshold.

15. A method according to claim 11, comprising:

sending to a remote monitoring location information indicative of which pumping power has been selected.