Startup method of Francis turbine and Francis turbine
AssigneesKabushiki Kaisha Toshiba, Toshiba Energy Systems & Solutions Corporation
InventorsMasahiko Nakazono, Takero Mukai, Yoshitaka Arihara
Life of this patent
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Abstract
A startup method of a Francis turbine according to an embodiment includes: a bypass-valve opening step of opening the bypass valve with the inlet valve closed; an inlet-valve opening step of opening the inlet valve after the bypass-valve opening step; and a first rotation-speed increasing step of increasing a rotation speed of the runner by opening the guide vane at an opening that is 50% or more of a maximum opening before a flow velocity of a swirling flow flowing around the runner reaches 90 m/sec.
Claims5
A startup method of a Francis turbine comprising an inlet valve provided to an inlet pipe that guides water to a casing, a bypass valve provided to a bypass pipe that bypasses the inlet valve and guides water to the casing, and a guide vane capable of regulating a flow rate of water to be guided to a runner provided in the casing, the startup method comprising:
- a bypass-valve opening step of opening the bypass valve with the inlet valve closed;
- an inlet-valve opening step of opening the inlet valve after the bypass-valve opening step;
- and
- a first rotation-speed increasing step of increasing a rotation speed of the runner by opening the guide vane at an opening that is 50% or more of a maximum opening before a flow velocity of a swirling flow flowing around the runner reaches 90 m/sec.
A Francis turbine comprising:
- a casing;
- an inlet pipe that guides water to the casing;
- an inlet valve provided to the inlet pipe;
- a bypass pipe that bypasses the inlet valve and guides water to the casing;
- a bypass valve provided to the bypass pipe;
- a runner provided in the casing;
- a guide vane capable of regulating a flow rate of water to be guided to the runner;
- and
- a control unit,
- wherein the control unit controls the inlet valve, the bypass valve and the guide vane to perform:
- a bypass-valve opening step of opening the bypass valve with the inlet valve closed;
- an inlet-valve opening step of opening the inlet valve after the bypass-valve opening step;
- and
- a first rotation-speed increasing step of increasing a rotation speed of the runner by opening the guide vane at an opening that is 50% or more of a maximum opening before a flow velocity of a swirling flow flowing around the runner reaches 90 m/sec.
Dependencies are inferred from the claim text.