Method for starting a turbine in a pump mode

Patent metadata

Field	Value
Publication number	US-11873789-B2
Application number	US-202017772662-A
Country	US
Kind code	B2
Filing date	Oct 29, 2020
Priority date	Oct 29, 2019
Publication date	Jan 16, 2024
Grant date	Jan 16, 2024

Abstract

The invention concerns a method for starting a hydroelectric turbine (10) in a pumping mode, said turbine being provided with a runner (6) mechanically coupled to a shaft line (8) and a variable speed electric motor connected to a grid, a distributor (4) comprising guide vanes to control a flow of water to said runner, the method comprising:a) a step of operating the variable speed motor at least partly at fixed speed, said guide vanes being only partially opened, and of defining or calculating:data of a plurality of hydraulic characteristics (C1, C2, Ci) of the turbine for an operation without cavitation;data of an operation range of the electric motor, giving the speed of the motor as a function of its power;b) then a step of operating the turbine in a power control mode.

First claim

The invention claimed is:

1. A method for starting a hydroelectric turbine in a pumping mode, said turbine being provided with a runner mechanically coupled to a shaft line and a variable speed electric motor connected to a grid, a distributor comprising guide vanes to control a flow of water to said runner, the method comprising:
a step (a) at start-up in the pumping mode of operating the variable speed motor at least partly at fixed speed in a non-optimal mode, said guide vanes being only partially opened during step (a);
a step (b) subsequent to step (a) wherein the turbine is operated in an optimal power control mode;
wherein before or during step (a), and of defining or calculating:
data of a plurality of hydraulic characteristics of the turbine for an operation without cavitation;
data of an operation range of the electric motor, giving the speed of the motor as a function of its power;

wherein the fixed speed of step (a) is maintained until a hydraulic head on the turbine reaches a minimum value for operation of the turbine in the optimal power control mode.

2. The method according to claim 1 , the fixed speed of step (a) is a speed at which the data of one of said hydraulic characteristics is equal to the data of said operation range of the electric motor.

3. The method according to claim 1 , wherein the fixed speed of step (a) is a being the lowest speed of the operation range of the electric motor.

4. The method according to claim 3 , wherein step (a) further comprises, after operating the variable speed motor at the fixed speed, varying the speed of the motor and the power absorbed by the motor according to a low speed side of the operation range of the electric motor.

5. The method according to claim 1 , wherein step (b) comprises operating the turbine according to one of said hydraulic characteristics of the turbine in the optimal power control mode.

6. The method according to claim 1 , wherein step (a) has a duration of at least one minute.

7. The method according to claim 1 , wherein steps (a) and (b) are performed under the control of a computer having stored data for speed and power of the motor and opening data of the guide vanes.

8. The method according to claim 1 , wherein the grid has an unstable frequency.

9. A hydroelectric turbine provided with a runner mechanically coupled to a shaft line and a variable speed electrical motor, said turbine further comprising a distributor comprising guide vanes to control a flow of water to said runner, said turbine further comprising a controller configured to start said hydroelectric turbine with the method according to claim 1 .

10. The hydroelectric turbine according to claim 9 , wherein said turbine is one of a pump-turbine, a Francis turbine, a Kaplan turbine, or a bulb turbine type.

11. The hydroelectric turbine according to claim 9 , said turbine being connected to a grid having a variable frequency.

12. A computer program comprising instructions for implementing the method according to claim 1 .

Assignees

• Ge Renewable Tech

Inventors

• Ruiz Sébastien
• Martinez Lionel

Classifications

• F03B3/10 Primary

  characterised by having means for functioning alternatively as pumps or turbines {(starting F03B15/005)} · CPC title

• F03B15/005

  Starting, also of pump-turbines · CPC title

• F03B15/02

  by varying liquid flow · CPC title

• F03B3/183

  Adjustable vanes, e.g. wicket gates · CPC title

• Y02E10/20

  Hydro energy · CPC title