This method allows determining the operating point of a hydraulic machine in a considered operating range, such as turbine mode, and comprises steps that consist in a) determining two coordinates (N′11, T′11) of a first series of potential operating points of the hydraulic machine for the orientation affected to guide vanes of the machine, b) measuring the rotation speed of the machine, and c) determining the torque exerted by water flow on the machine. The method further includes steps consisting in d) calculating two coordinates (N11, T11) of a second series of potential operating points of the machine in function of the rotation speed (N) measured at step b) and the torque determined at step c), and e) deducing the two coordinates (N11_real, T11_real) of operating point that belongs both to the first and the second series in the said considered operating range of the machine.

A startup method of a Francis turbine according to an embodiment includes: a first rotation-speed increasing step in which a rotation speed of the runner is increased by opening the guide vane at a first opening; a second rotation-speed increasing step in which the increase in the rotation speed of the runner is accelerated by opening the guide vane at a second opening that is larger than the first opening after the first rotation-speed increasing step; and a rotation-speed regulating step in which the rotation speed of the runner is regulated to a rated rotation speed by opening the guide vane at a no-load opening after the second rotation-speed increasing step. The first opening is an opening that is half or less than the no-load opening.

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.

A runner for a hydraulic turbine or pump includes a plurality of blades, each blade being defined by a pressure surface, an oppositely facing suction surface, a leading edge and a spaced apart trailing edge. At least one blade has a device for supplying a flow of oxygen containing gas to the trailing edge of at least one of the blades. The profile of the suction side surface of the blade along a cross section through a point P1 and a point P2 is concave. The point P1 is located on the suction side surface of the trailing edge where an opening is located, the point P2 is spaced apart from the point P1 by less than 3% of the runner outlet diameter D and the point P2 is located upstream of the point P1 on a line perpendicular to the trailing edge starting at the point P1.

A hydroelectric power generation system includes: a generator driven by the hydraulic turbine; a head adjuster adjusting an effective head of the hydraulic turbine; and a controller cooperatively executing: flow rate control for controlling the generator such that a flow rate in the hydraulic turbine is brought close to a target flow rate; and head adjusting control for adjusting the effective head of the hydraulic turbine using the head adjuster such that the effective head of the hydraulic turbine falls within a first range.

A method for stabilizing the rotation speed of a machine with S-characteristics is provided. The method includes calculating a target net head and a target opening to affect guide vanes of the machine, the target net head and the target opening being calculated so that the torque exerted by water flow on the turbine is null and that the machine rotates at a target rotation speed; determining a real net head to which the machine is subjected; comparing the target net head with the real net head; and adjusting the opening of the guide vanes so as to converge towards the target opening and reduce a height difference between the target net head and the real net head.

A wicket gate for a hydraulic turbine or pump contains a blade being defined by a pressure surface, an oppositely facing suction surface, a leading edge and a spaced apart trailing edge, a first trunnion, a second trunnion, an air inlet aperture, an air passage and at least one air outlet aperture. The profile of the suctions side surface of the blade along a cross section through a point P1 and a point P2 is concave. Whereas point P1 is located on the suction side surface of the trailing edge where an air outlet aperture is located and point P2 is spaced apart from point P1 by less than 10% of the wicket gate length D and point P2 is located upstream of point P1 on a line perpendicular to the trailing edge starting at point P1.

A guide vane bearing for a hydraulic machine is provided, which may be serviced from the side of the water flow path, and a method for installing and removing a bearing of this type. The guide vane bearing includes a bearing support and a layer of bearing material and at least three segments, which are separately connectable to the bottom ring of the hydraulic machine, each segment including one part of the bearing support and one part of the layer of bearing material, and a joint between the segments being obliquely formed with respect to the bearing axis, so that one segment has a wedge shape, and the bearing furthermore including a bearing seal, and the bearing seal being rotatably fixedly connected to the trunnion of the guide vane, and the bearing support including a surface, which is designed as a running surface for the lip of the bearing seal.

A reversible pump-turbine and also a guide vane for a reversible pump-turbine with a guide vane body, a pivot for rotating the guide vane body around an axis of rotation and two end faces. The guide vane body has a turbine leading edge facing the turbine flow and a turbine trailing edge facing away from the turbine flow, where the individual guide vanes come into contact with one another along closing edges when the wicket gate is closed, where the guide vanes each have two flow-guiding surfaces on either side of the axis of rotation and opposite one another that are limited by the two end faces. These two flow-guiding surfaces have different flow profiles.

A power generation plant including a turbine (1) of a Kaplan, bulb, diagonal flow or propeller turbine type, a water intake (4) and a water run-off (5). Additional vanes vane (8) are deployable into a water passage formed between the water intake (4) and the housing of the turbine. Eddy flows formed in the water intake (4) are reduced by the additional vanes. The vanes allow the turbine operating range to be extended to cover smaller outputs.