摘要:
A permanent magnet rotor comprising a rotor rim and a plurality of permanent magnet modules arranged on the outer or inner circumference of the rotor rim, the permanent magnet modules extending generally along an axial direction and being of substantially constant axial-cross section, and comprising a base adapted to be fixed to the rim of the generator rotor, one or more permanent magnets, and one or more pole pieces, wherein the permanent magnet modules comprise an axial cooling channel extending substantially along the length of the modules.
摘要:
An electric machine with a closed circuit air cooling provides using only passive elements to realize an efficient and compact heat transfer from inside the electric machine to an ambient heat sink.
摘要:
The invention relates to a Francis runner (200) for a hydraulic machine, comprising: a wheel (1), which is rotationally symmetrical about an axis of rotation (Z) of the runner (200); a crown (12); and a plurality of inwardly curved vanes (21), each of which has a peripheral edge (212). The peripheral edge (212) of at least one of the vanes is curved, the concavity thereof facing toward the outside of the runner (200). The maximum value of the distance measured between any point on the peripheral edge (202) and a straight line passing through a first connection point between the peripheral edge (212) and the wheel (1), and through a second connection point between the peripheral edge (212) and the crown (12), is at an intermediate point on the peripheral edge (212). The radius (Rn) from the intermediate point (N) is strictly smaller than the radius (Ra) from the first connection point (A). The radius (Rn) from the intermediate point (N) is strictly smaller than the radius (Rc) from the second connection point (C).
摘要:
An end winding corona protection including a winding of a rotating electric machine, having a conductor and a groundwall insulation surrounding the conductor, an end winding corona protection arranged on the outer surface of the groundwall insulation, the end winding corona protection comprising a first layer characterized in that the surface resistance of the first layer is in the range of 10 Ohm to 80 Ohm, and in that the end winding corona protection further comprises a second layer arranged on the outer surface of the first layer, wherein the second layer is made of semiconductive material, and wherein third layer is arranged on the outer surface of the second layer and made of medium resistive material.
摘要:
A propeller for a hydraulic machine includes a hub extending along an axis of rotation of the propeller and vanes extending from the hub and wherein the propeller is formed of several sectors each including a body having a vane attached thereto and wherein the sectors are assembled together by at least one shrunk-on ring which is placed around the bodies. Each sector also includes a side wall and a projection attached to the side wall and which protrudes toward an inside of the hub perpendicularly to the axis (X-X) and wherein at least one washer is connected to the projections inside the hub.
摘要:
Methods and arrangements for controlling the tension of tensioning cables in precompressed towers are disclosed. The towers may comprise a tower section (5), a pair of flanges (15, 15′), a plurality of tensioning cables (10A-10D)and at least one tensioner (30AB, 30CD). The pair of flanges may be arranged around an upper and a lower part of the tower section. The at least one tensioner may be arranged between two of the plurality of tensioning cables (10A-10D). The tensioner may pull the tensioning cables in response to a load signal to increase the tension.
摘要:
The present invention relates to a Francis runner for a hydraulic machine that comprises a belt with a rotational symmetry about a central axis of the runner, a ceiling with a rotational symmetry about the axis, and a plurality of blades (21, 22) extending between the ceiling and the belt. The runner also includes at least two elements (41, 42, 43, 61, 62, 63) partially defining at least the belt and/or the ceiling while at least one edge (231, 232, 241, 242) of a blade (21, 22) is inserted between the two elements defining the belt and/or the ceiling.
摘要:
A rotating electric machine includes a rotor, having a rotor laminate stack extending in the direction of a machine axis and having a rotor winding, the rotor winding forming a winding head at each of the ends of the rotor laminate stack, said winding head being fastened to a winding head rim, which is arranged concentrically within the winding head and adjoins the rotor laminate stack in the axial direction, in order to intercept centrifugal forces by means of bolts passing radially through the winding head, and a fastening designed to safely absorb axial expansions of the winding head. Simple and secure fastening is achieved by virtue of the bolts being fastened to the winding head rim in each case on a T-shaped hammer profile, which extends in the axial direction and is mounted in axially movable fashion in an associated axial T-shaped slot in the winding head rim.
摘要:
Systems for providing electrical power to one or more wind turbine electrical components is provided comprising an electrical grid and an auxiliary power source for providing electrical power, and one or more wind turbines. Each of the wind turbines includes a wind turbine generator, one or more electrical components, a main voltage transformer for connecting the wind turbine generator to the grid and a switchgear arranged between the main voltage transformer and a point of connection to the grid. One or more switches for alternately connecting either said electrical grid or said auxiliary power source to the switchgears of the wind turbines are provided. The switchgears comprise a switchgear voltage transformer, the switchgear voltage transformer includes primary and secondary windings, the primary windings receiving power from the electrical grid or auxiliary power source, and the secondary windings delivering electrical power to the wind turbine electrical components.
摘要:
Method for avoiding voltage instability in an electrical grid of an offshore wind park, the offshore wind park electrical grid being connected at a first end of a high voltage alternating current (HVAC) transmission and the main land electrical grid being connected at a second end of the HVAC transmission, each of the wind turbines being connected to the wind park electrical grid, the method comprises determining a main land phase angle at or near the second end of the HVAC transmission; measuring an individual wind turbine phase angle at one or more wind turbines; determining the difference between each of the measured individual wind turbine phase angles and the main land phase angle; and determining whether the difference between one of the measured individual wind turbine phase angle and the main land phase angle exceeds a threshold phase angle difference.