A hydraulic turbine includes a rotor with a runner, which is concentrically surrounded by a stator, whereby the runner comprises a plurality of runner blades arranged and distributed in a ring around a rotor axis, and each runner blade extends between a runner crown and a runner band; whereby the stator comprises a plurality of guide vanes arranged and distributed in a ring around the rotor axis, and each guide vane extends between an upper stator ring and a lower stator ring; and whereby a predetermined clearance is provided at least between the runner band and the lower stator ring. A substantial reduction of pressure pulsations in the vane-less gap between said runner blades of said runner is achieved by substantially increasing said predetermined clearance.

A hydraulic turbine includes a rotor with a runner, which is concentrically surrounded by a stator, whereby the runner comprises a plurality of runner blades arranged and distributed in a ring around a rotor axis, and each runner blade extends between a runner crown and a runner band; whereby the stator comprises a plurality of guide vanes arranged and distributed in a ring around the rotor axis, and each guide vane extends between an upper stator ring and a lower stator ring; and whereby a predetermined clearance is provided at least between the runner band and the lower stator ring. A substantial reduction of pressure pulsations in the vane-less gap between said runner blades of said runner is achieved by substantially increasing said predetermined clearance.

A method of refurbishing a facility for converting hydraulic energy into electrical energy including the following steps: providing a first cover plate, a second cover plate, a first opening located at an inner head cover, a second opening located at a hub, a third opening located at a runner; connecting the first cover plate to the inner head cover; connecting the second cover plate to the hub, wherein the first cover plate and the second cover plate surround an axis, and a part of an outer surface of the inner head cover, a part of an outer surface of the hub, an inner surface of the first cover plate, and an inner surface of the second cover plate are confining an annular shaped space.

A hydro turbine of a hydroelectric power plant operates with reduced cavitation at low power levels. A using at least one motion sensor coupled to a rotor of the hydro turbine, during operation of the hydro turbine is used to generate at least one metric indicative of an effect of cavitation on the hydro turbine. The metric is used by an automated governing system to change the operation of the hydro turbine to reduce cavitation.

A hydro turbine of a hydroelectric power plant operates with reduced cavitation at low power levels. A using at least one motion sensor coupled to a rotor of the hydro turbine, during operation of the hydro turbine is used to generate at least one metric indicative of an effect of cavitation on the hydro turbine. The metric is used by an automated governing system to change the operation of the hydro turbine to reduce cavitation.

The invention relates to a hydraulic machine having an impeller wheel that comprises a plurality of impeller blades; having a spiral housing that encloses the impeller wheel and that is open toward said impeller wheel by a circumferential slit formed by two circumferential edges; having a traverse ring, comprising two traverse ring decks that are connected to one another by tension anchors; wherein the spiral housing is composed of segments that meet in the flow direction and that are welded to each other, the ends of which segments stand on the respective traverse ring deck and are welded to said deck; wherein at the meeting point between two segments that are adjacent to one another and one traverse ring deck a stiffening element is provided that protrudes into the inner space of the spiral housing; and wherein the extension of the stiffening element into the inner space of the spiral housing is so small that the flow is not affected in a significant manner.

The invention relates to a hydraulic machine having an impeller wheel that comprises a plurality of impeller blades; having a spiral housing that encloses the impeller wheel and that is open toward said impeller wheel by a circumferential slit formed by two circumferential edges; having a traverse ring, comprising two traverse ring decks that are connected to one another by tension anchors; wherein the spiral housing is composed of segments that meet in the flow direction and that are welded to each other, the ends of which segments stand on the respective traverse ring deck and are welded to said deck; wherein at the meeting point between two segments that are adjacent to one another and one traverse ring deck a stiffening element is provided that protrudes into the inner space of the spiral housing; and wherein the extension of the stiffening element into the inner space of the spiral housing is so small that the flow is not affected in a significant manner.

The double-regulated turbine comprises a spherical hub, adapted to rotate around a first rotation axis, and blades, which are each able to be swivelled relative to the hub around a second rotation axis, transversal to the first rotation axis, by respective coupling flanges that are mounted fixedly on the spherical hub and that include each an attachment surface for a corresponding blade. The attachment surface of the coupling flanges includes a flat portion.

A hydro turbine of a hydroelectric power plant operates with reduced cavitation. At least one motion sensor coupled to a rotor of the hydro turbine measures motion of the rotor during operation of the hydro turbine and generates measurement data. The measurement data and one or more operational parameters of the hydro turbine employed during the measuring are acquired. The operational parameter(s) is/are indicative of power supply of the hydro turbine. Based on the measurement data and the operational parameters, at least one metric indicative of an effect of the cavitation on the hydro turbine is computed. The at least one metric is compared with at least one threshold. Based on the comparison, a determination is made that the effect of the cavitation is too high. Based on the determining, information indicating unsuitability of the one or more operational parameters is output.

A hydro turbine of a hydroelectric power plant operates with reduced cavitation. At least one motion sensor coupled to a rotor of the hydro turbine measures motion of the rotor during operation of the hydro turbine and generates measurement data. The measurement data and one or more operational parameters of the hydro turbine employed during the measuring are acquired. The operational parameter(s) is/are indicative of power supply of the hydro turbine. Based on the measurement data and the operational parameters, at least one metric indicative of an effect of the cavitation on the hydro turbine is computed. The at least one metric is compared with at least one threshold. Based on the comparison, a determination is made that the effect of the cavitation is too high. Based on the determining, information indicating unsuitability of the one or more operational parameters is output.