Method for starting up a system for generating electrical power

• US 20090278350A1
• Filed: 06/11/2008
• Published: 11/12/2009
• Est. Priority Date: 05/10/2008
• Status: Active Grant

• Current Assignee: Converteam Technology Ltd. (General Electric Company)
• Original Assignee: Converteam Technology Ltd. (General Electric Company)
• Inventors: Bocquel, Aurelie, Moehlenkamp, Georg
• Granted Patent: US 8,212,534 B2
• Time in Patent Office: Days
• US Class Current: 290/43
• CPC Class Codes: H02P 1/46 for starting an individual synchronous motor H02P27/04 takes precedence
• CPC Class Codes: H02P 9/08 Control of generator circuit during starting or stopping of driving means, e.g. for initiating excitation

Abstract

Described is a method for starting up a system for generating electrical power. The system includes a turbine that is mechanically connected to a generator, while the generator is electrically connected via a converter to a load, in particular to a power supply grid. The generator includes a total number of windings. With at least one embodiment of the method, a number of generator windings are combined at low rotational speeds of the turbine, wherein the combined number of windings is less than the total number of windings.

Claims

1. A method for starting up a system for generating electrical power, the system including a turbine that is mechanically connected to a generator, the generator being electrically connected via a converter to a load, and the generator including a total number of windings, the method comprising:

combining a number of the generator windings at low rotational speeds of the turbine, wherein the number of combined windings is lower than the total number of windings.

2. The method according to claim 1, wherein the number of windings are combined at rotational speeds of the turbine that correspond approximately to 30% to 50% of the operating speed for the turbine.

3. The method according to claim 1, wherein the number of windings are combined during a first time interval.

4. The method according to claim 1, wherein the number of windings are combined starting with the standstill of the turbine.

5. The method according to claim 1, wherein the generator includes polygonal-shaped windings and wherein the windings are combined in an essentially symmetrical arrangement within the generator.

6. The method according to claim 1, wherein the converter includes a plurality of switching devices, in particular thyristors, and wherein the generator windings are combined by blocking corresponding switching devices.

7. The method according to claim 6, wherein the non-blocked switching devices are commutated in dependence on the load.

8. The method according to claim 1, wherein with an increasing rotational speed of the turbine, the magnetic flux of the generator is first kept constant and is then reduced.

9. The method according to claim 1, wherein for the start-up of the system, the converter is commutated at higher rotational speeds of the turbine in dependence on the generator.

14. The method according to claim 2, wherein the number of windings are combined at rotational speeds of the turbine that correspond approximately to approximately 40% of the operating speed.

15. The method according to claim 2, wherein the number of windings are combined during a first time interval.

16. The method according to claim 2, wherein the number of windings are combined starting with the standstill of the turbine.

17. The method according to claim 6, wherein the switching devices are thyristors, and wherein the generator windings are combined by blocking corresponding thyristors.

18. The method according to claim 7, wherein the load is an energy supply grid and wherein the non-blocked switching devices are commutated in dependence on the energy supply grid.

10. A system for generating electrical power, comprising:

a turbine, mechanically connected to a generator, the generator being electrically connected via a converter to a load, the generator including a total number of windings; and

means for combining, at low turbine rotational speeds, a number of windings of the generator functioning as a motor, wherein the combined number of windings is lower than the total number of windings of the generator.

11. The system according to claim 10, wherein the generator is embodied as synchronous generator.

12. The system according to claim 10, wherein the converter is embodied as a matrix converter.

13. The system according to claim 10, wherein a transformer is provided, for which the windings have intermediate taps, and wherein a switch is assigned to the transformer, by which the converter is connectable to the intermediate taps.

19. The system according to claim 11, wherein the generator is embodied as synchronous generator with polygonal-shaped windings.

20. The system according to claim 11, wherein the converter is embodied as a matrix converter.