Electric generator arrangement and method for reducing a rotor eccentricity
AssigneeSiemens Aktiengesellschaft
InventorsEDOM LEMMA, ARWYN THOMAS
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Abstract
An electric generator arrangement with a stator being equipped with at least two opposed phase windings, each winding comprising at least two sub-windings in series is provided. The arrangement also comprises a controlled varistor across the connections of the sub-windings of said opposed phase windings. A current imbalance between two opposed phase windings is measured and the varistor is controlled in such a way that the resistance of the varistor is increased when the current imbalance increases.
Claims8
An electric generator arrangement, comprising:
- a generator having a stator and a rotor mounted to said stator free to rotate, wherein the stator is equipped with at least two opposed phase windings/segments, each winding/segment comprising at least two sub-windings in series, a controlled varistor across the connections of the sub-windings of said at least two opposed phase windings/segments, a sensor for measuring the current imbalance of two opposed phase windings/segments of said electric generator and
- an electronic circuit for controlling said varistor in such a way that the resistance of the varistor is increased when the current imbalance between said opposed phase windings/segments increases.
A wind turbine comprising an electric generator arrangement comprising:
- at least one turbine blade;
- and
- a generator having a stator and a rotor mounted to said stator free to rotate, wherein the stator is equipped with at least two opposed phase windings/segments, each winding/segment comprising at least two sub-windings in series, a controlled varistor across the connections of the sub-windings of said at least two opposed phase windings/segments,
- a sensor for measuring the current imbalance of two opposed phase windings/segments of said electric generator and
- an electronic circuit for controlling said varistor in such a way that the resistance of the varistor is increased when the current imbalance between said opposed phase windings/segments increases, wherein the generator is coupled to the rotor of the wind turbine.
A method of controlling a rotor eccentricity of an electric generator arrangement, the generator having said rotor mounted to a stator free to rotate, the stator being equipped with at least two opposed phase windings/segments, each winding comprising at least two sub-windings in series, and the arrangement comprising a controlled varistor across the connections of the sub-windings of said opposed phase windings/segments, the method comprising the steps of:
- measuring the current imbalance of two opposed phase windings/segments of said electric generator and
- controlling said varistor in such a way that the resistance of the varistor is increased when the current imbalance increases.
Dependencies are inferred from the claim text.