Abstract: Provided is a method and arrangement for controlling a multi winding set permanent magnet electrical machine in case of a fault in a first group of the winding sets leaving a second group of the winding sets functional, the method comprising: determining a value of a torque generated by all winding sets; and controlling values of currents of the second group of winding sets based on the value of a torque, in order to reduce a damaging torque and/or a torque oscillation occurring and/or to break the machine.

Abstract: Provided is a method of diagnosing at least one winding set of a stator of a generator during operation, the winding set having plural wires for plural phases, the method including: obtaining, for each of the plural wires of the winding set, an individual strength of an individual power output from the respective wire of the plural wires of the winding set; obtaining a sum strength of power; forming, for each considered wire of the plural wires of the winding set, an individual ratio between the individual strength of the considered wire and the sum strength; forming, for each considered wire of the plural wires of the winding set, a diagnostic value by subtracting from an individual ratio not corresponding to the considered wire a term depending on the individual ratio corresponding to the considered wire; diagnosing at least one wire based on comparing the diagnostic values.

Abstract: Provided is an arrangement for determining an operation parameter reference for controlling a generator side converter portion coupled to a generator, in particular of a wind turbine, the arrangement comprising: an arithmetic element configured to derive a fundamental current error by subtracting a, in particular unfiltered, generator output current from a sum of a fundamental current reference and at least one harmonic current reference; a fundamental current controller adapted to determine a fundamental operation parameter reference based on the fundamental current error; at least one other arithmetic element configured to derive at least one harmonic current error by subtracting a, in particular band pass filtered according to the harmonics, generator output current from the at least one harmonic current reference; at least one harmonic current controller configured to determine at least one harmonic operation parameter reference based on the harmonic current error.

Abstract: An arrangement for determining a d-component (Idref, I*d) of a reference current in a d-q coordinate system for reducing noise of a wind turbine, the arrangement including a noise/vibration determination module for determining noise/vibration components of oscillations of at least one wind turbine component, and a processing block for calculating a first type of the d-component of the reference current based on the noise/vibration component output by the noise/vibration determination module, is provided.

Abstract: A control arrangement of a multiple-stator machine, comprising a frequency converter for each of the plurality of stators and a controller for each frequency converter, wherein a controller of a frequency converter is realized to generate control signals for that frequency converter on the basis of current values relating to that stator, and to generate a compensation current value for a further controller on the basis of the received current values in the event of an open-circuit fault in a frequency converter; to receive a compensation current value from a further controller; and to compute a voltage reference for a subsequent transform stage of the controller on the basis of the received current values is provided. The invention further describes a current control module of a frequency converter controller of such a multi-stator machine; a multi-stator machine; and a method of performing fault-tolerant control of a multi-stator machine.

Abstract: An arrangement for determining a d-component (Idref, I*d) of a reference current in a d-q coordinate system for reducing noise of a wind turbine, the arrangement including a noise/vibration determination module for determining noise/vibration components of oscillations of at least one wind turbine component, and a processing block for calculating a first type of the d-component of the reference current based on the noise/vibration component output by the noise/vibration determination module, is provided.