Siemens Aktiengesellschaft

Siemens Gamesa Renewable Energy A/s

Heng Deng

Per Egedal

Thomas Esbensen

Gustav Hoegh

Zhan-Yuan Wu

Erik Groendahl

Nuno Miguel Amaral Freire

Bo Yin

Nuno Miguel Amaral Friere

Ge Xie

Provided is a method of controlling a permanent magnet generator, the method including: measuring mechanical noise of the generator; deriving two quantities indicative of an amplitude and a phase of an undesired harmonic of the measured noise; deriving, based on the quantities, a current to be injected in stator coils of the generator such as to reduce the undesired harmonic.

Controlling a wind turbine generator

Provided is a method of damping mechanical oscillations of plural wind turbines of a wind park commonly supplying electric energy to a grid, the method including: determining, for each of the plural wind turbines, a damping control signal for counteracting an oscillation of the respective wind turbine; supplying at least a subset of or a subset of modified versions of the damping control signals to respective wind turbines such that a sum of the supplied damping control signals is lower than a threshold.

Damping mechanical oscillations of a wind turbine

Provided is a control arrangement for controlling an electrical machine, including: a fundamental current controller, at least one harmonic flux controller related to a harmonic of an electrical frequency of the electrical machine, a summation system for adding voltage commands to obtain a summed voltage command based on which the electrical machine.

Control arrangment for a generator

A method, an arrangement and a computer program for controlling an energy flow to a grid, from an electrical alternating current machine with unbalanced impedance, in particular an electrical alternating current generator of a wind turbine, the method comprising: obtaining a first power signal representing a first power command.

Controlling the energy flow from an electrical machine with unbalanced impedance

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.

Noise control for a wind turbine

A method to detect a decrease of the demagnetization of permanent magnets of the generator of a wind turbine, wherein a frequency converter is able to adapt to the variable frequency of the generator output voltage to the frequency of a power grid, wherein the AC/DC converter or the DC/AC converter of the frequency converter is been disabled, the electrical connections between the generator and the frequency converter are switched on via circuit breakers, the generator speed is determined; the generator output voltage is determined by a voltage sensor which is part of the frequency converter, the magnetic flux density of the generator is calculated depending on the generator speed and the generator output voltage, a demagnetization event is determined by comparing the resulting flux density value with a predetermined flux density value is provided.

Method to detect or monitor the demagnetization of a magnet

A method and an apparatus for determining a phase and a frequency of an electric quantity being associated with an operation of an electrical device are described. The method comprises extracting a fundamental component of the electric quantity, calculating a positive sequence component of the electric quantity based on the extracted fundamental component, and determining the phase and the frequency of the electric quantity based on the calculated positive sequence component.

Determining a phase and a frequency of an electric quantity of an operating electrical device

A method is provided for controlling a DC link voltage of a power converter connecting an electric generator of a wind turbine with a power grid. The method includes determining the rotational speed of a rotor of the electric generator. The method further includes determining a strength of harmonic components of the rotational speed of the rotor, wherein the harmonic components have frequency components being different from a fundamental rotational frequency of the electric generator. The method also includes determining a damping reference signal as a function of the determined strength of the harmonic components, and controlling the DC link voltage of the power converter in response to the determined damping reference signal. A corresponding control system is also provided.

Method and system for controlling a DC link voltage of a power converter connecting an electric generator of a wind turbine with a power grid

A method for controlling the operation of an electromechanical transducer is provided. The method includes (a) determining during a first period of time a first strength of the harmonic operational behavior of the transducer, (b) determining during a second period of time a second strength of the harmonic operational behavior of the transducer, wherein the second period of time is different from the first period of time, (c) calculating a harmonic control signal in response to both the determined first strength of the harmonic operational behavior and the determined second strength of the harmonic operational behavior, (d) generating a modified drive signal based on the calculated harmonic control signal, and (f) supplying the generated modified drive signal to electromagnetic coils of a stator of the transducer. Further, a corresponding control system for controlling the operation of an electromechanical transducer is provided.

Reduction of noise and vibrations of an electromechanical transducer by using a modified stator coil drive signal comprising harmonic components

A current controller for controlling plural stator currents of plural stator windings of an electrical machine, in particular a generator, is provided, wherein the plural windings are separately connectable to a converter. The current controller includes a positive-sequence current controller configured to provide a first voltage command, in particular in a rotating dq+ frame, based on the plural stator currents; a negative-sequence current controller configured to provide a second voltage command, in particular in the dq+ frame, based on the plural stator currents. Further, the current controller includes a summation system for adding the first voltage command and the second voltage command to obtain a summed voltage command based on which the converter is controllable.

Current controller and generator system

A method for controlling a generator having a rotor with a plurality of magnets and a first stator winding and a second stator winding, electrically separate from the first stator winding is provided. The rotor rotates around a rotation axis perpendicular to a radial direction relative to the stator windings. The method includes allowing flow of a first electric current through the first stator winding, thereby generating a first radial force having a first magnitude and acting between the first stator winding and the rotor, and allowing flow of a second electric current through the second stator winding, thereby generating a second radial force having a second magnitude and acting between the second stator winding and the rotor, wherein the first magnitude is different from the second magnitude resulting in a net generator generated radial force generated by the first stator winding and the second stator winding at the rotor.

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Ikast, Denmark

Heng Deng