Patents by Inventor John Godsk Nielsen

John Godsk Nielsen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11955800
    Abstract: Aspects of the present invention relate to a method of voltage control for at least one wind turbine generator configured to absorb and supply reactive power on demand, the method comprises: receiving a dispatch signal from a power plant controller indicating a reactive power set point; determining a terminal voltage level of the at least one wind turbine generator; generating a reactive power correction value based on a deviation of the terminal voltage level from a voltage set point; adjusting the reactive power set point by the reactive power correction value; and controlling the at least one wind turbine generator according to the adjusted reactive power set point.
    Type: Grant
    Filed: May 6, 2021
    Date of Patent: April 9, 2024
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Torsten Lund, Germán Claudio Tarnowski, John Godsk Nielsen, Per Hagen Nielsen
  • Publication number: 20240079978
    Abstract: The invention relates to a method for controlling a power generating unit. The method includes determining a virtual impedance value, determining a virtual grid power based on the virtual resistance value and the grid current, determining a virtual synchronous machine rotational speed and/or a synchronous machine angle of a virtual synchronous generator, and determining a voltage reference for controlling a line side converter to generate the desired reactive power based on the virtual synchronous machine rotational speed or angle, a virtual voltage and the voltage magnitude reference.
    Type: Application
    Filed: November 10, 2023
    Publication date: March 7, 2024
    Inventors: Esmaeil EBRAHIMZADEHVESHAREH, Torsten LUND, John Godsk NIELSEN
  • Patent number: 11901734
    Abstract: A grid side inverter system includes a grid side inverter, a phase locked loop controller arranged to determine a phase of a dq-frame dependent on a monitored grid voltage vector in the dq-frame and a reference grid voltage vector in the dq-frame, a current reference decision unit arranged to generate a reduction of at least one of an active and a reactive current reference, wherein a decision to generate the reduction is based on an electrical parameter relating to the phase difference of the monitored grid voltage vector and the PLL vector, a current controller arranged to determine control signals for the grid side inverter for controlling generation of active and reactive power to the grid dependent on the active and reactive current references and monitored active and a reactive grid currents in the dq-frame.
    Type: Grant
    Filed: June 3, 2022
    Date of Patent: February 13, 2024
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: John Godsk Nielsen, Torsten Lund, Hamid Soltani, Gert Karmisholt Andersen
  • Patent number: 11863112
    Abstract: The invention relates to controlling a power generating unit. Aspects of the invention include determining a virtual impedance value (Zvir), determining a virtual grid power (Pvsm) based on the virtual resistance value (Rvir) and the grid current (Igrid), determining a virtual synchronous machine rotational speed (?VSM) and/or a synchronous machine angle (?VSM) of a virtual synchronous generator, and determining a voltage reference (Vabc) for controlling a line side converter to generate the desired reactive power (Qgrid) based on the virtual synchronous machine rotational speed or angle (?VSM, ?VSM), a virtual voltage (?V??, ?Vdq) and the voltage magnitude reference (Vqref).
    Type: Grant
    Filed: July 8, 2020
    Date of Patent: January 2, 2024
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Esmaeil Ebrahimzadehveshareh, Torsten Lund, John Godsk Nielsen
  • Publication number: 20230344230
    Abstract: A grid side inverter system includes a grid side inverter, a phase locked loop controller arranged to determine a phase of a dq-frame dependent on a monitored grid voltage vector in the dq-frame and a reference grid voltage vector in the dq-frame, a current reference decision unit arranged to generate a reduction of at least one of an active and a reactive current reference, wherein a decision to generate the reduction is based on an electrical parameter relating to the phase difference of the monitored grid voltage vector and the PLL vector, a current controller arranged to determine control signals for the grid side inverter for controlling generation of active and reactive power to the grid dependent on the active and reactive current references and monitored active and a reactive grid currents in the dq-frame.
    Type: Application
    Filed: June 3, 2022
    Publication date: October 26, 2023
    Inventors: John Godsk NIELSEN, Torsten Lund, Hamid Soltani, Gert Karmishoit Andersen
  • Patent number: 11728650
    Abstract: The invention relates to a method for operating a power system of a wind turbine. The power system comprises first and second parallel connected DC-to-AC converters and at least one transformer, where each transformer comprises a primary section connected to a power line, and where the at least one transformer comprises first and second secondary sections connected to outputs of the respective first and second DC-to-AC converters. The method comprises providing a reactive correction reference, changing first and second reactive powers generated by the respective first and second DC-to-AC converters according to the reactive correction reference, so that one of the first and second reactive powers is increased while the other is decreased with amounts corresponding to the reactive correction reference so that the first and second reactive powers are unequal.
    Type: Grant
    Filed: July 9, 2021
    Date of Patent: August 15, 2023
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: John Godsk Nielsen, Torben Møller Hansen
  • Patent number: 11715955
    Abstract: The invention relates to a method for controlling a power generating unit such as a wind turbine which is configured as a virtual synchronous machine. Capacitor voltage signals obtained from voltage measurements of output capacitors are filtered in order to reduce a magnitude of an impedance peak and/or shift the impedance peak where the impedance peak is present in an impedance characteristic of the output of the power generating unit. Filter compensated voltage signals obtained from the output capacitors are combined with a voltage magnitude reference to obtain filtered capacitor voltage signals used for controlling the line side converter and thereby affect the impedance peak in a desired way.
    Type: Grant
    Filed: December 16, 2019
    Date of Patent: August 1, 2023
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: John Godsk Nielsen, Torsten Lund, Esmaeil Ebrahimzadehveshareh
  • Publication number: 20230178988
    Abstract: Aspects of the present invention relate to a method of voltage control for at least one wind turbine generator configured to absorb and supply reactive power on demand, the method comprises: receiving a dispatch signal from a power plant controller indicating a reactive power set point; determining a terminal voltage level of the at least one wind turbine generator; generating a reactive power correction value based on a deviation of the terminal voltage level from a voltage set point; adjusting the reactive power set point by the reactive power correction value; and controlling the at least one wind turbine generator according to the adjusted reactive power set point.
    Type: Application
    Filed: May 6, 2021
    Publication date: June 8, 2023
    Inventors: Torsten LUND, Germán Claudio TARNOWSKI, John Godsk NIELSEN, Per Hagen NIELSEN
  • Publication number: 20220321041
    Abstract: The invention relates to controlling a power generating unit. Aspects of the invention include determining a virtual impedance value (Zvir), determining a virtual grid power (Pvsm) based on the virtual resistance value (Rvir) and the grid current (Igrid), determining a virtual synchronous machine rotational speed (?VSM) and/or a synchronous machine angle (?VSM) of a virtual synchronous generator, and determining a voltage reference (Vabc) for controlling a line side converter to generate the desired reactive power (Qgrid) based on the virtual synchronous machine rotational speed or angle (?VSM, ?VSM), a virtual voltage (?V??, ?Vdq) and the voltage magnitude reference (Vqref).
    Type: Application
    Filed: July 8, 2020
    Publication date: October 6, 2022
    Inventors: Esmaeil EBRAHIMZADEHVESHAREH, Torsten LUND, John Godsk NIELSEN
  • Publication number: 20220085740
    Abstract: The invention relates to a method for controlling a wind turbine as virtual synchronous machine by determining the synchronous machine rotational speed rotational speed and the synchronous machine angle. The virtual synchronous machine rotational speed is determined based on a combination of a feedback of a damping power, a power reference for a desired power output of the wind turbine, a grid power supplied by the wind turbine to a power grid and a chopper power dissipated by the chopper and an inertial integration model, the synchronous machine angle is determined based on an integration of the synchronous machine rotational speed, and the damping power is determined based on the virtual synchronous machine rotational speed.
    Type: Application
    Filed: December 16, 2019
    Publication date: March 17, 2022
    Inventors: John Godsk NIELSEN, Torsten LUND, Esmaeil EBRAHIMZADEHVESHAREH
  • Publication number: 20220069580
    Abstract: The invention relates to a method for controlling a power generating unit such as a wind turbine which is configured as a virtual synchronous machine. Capacitor voltage signals obtained from voltage measurements of output capacitors are filtered in order to reduce a magnitude of an impedance peak and/or shift the impedance peak where the impedance peak is present in an impedance characteristic of the output of the power generating unit. Filter compensated voltage signals obtained from the output capacitors are combined with a voltage magnitude reference to obtain filtered capacitor voltage signals used for controlling the line side converter and thereby affect the impedance peak in a desired way.
    Type: Application
    Filed: December 16, 2019
    Publication date: March 3, 2022
    Inventors: John Godsk NIELSEN, Torsten LUND, Esmaeil EBRAHIMZADEHVESHAREH
  • Publication number: 20220014023
    Abstract: The invention relates to a method for operating a power system of a wind turbine. The power system comprises first and second parallel connected DC-to-AC converters and at least one transformer, where each transformer comprises a primary section connected to a power line, and where the at least one transformer comprises first and second secondary sections connected to outputs of the respective first and second DC-to-AC converters. The method comprises providing a reactive correction reference, changing first and second reactive powers generated by the respective first and second DC-to-AC converters according to the reactive correction reference, so that one of the first and second reactive powers is increased while the other is decreased with amounts corresponding to the reactive correction reference so that the first and second reactive powers are unequal.
    Type: Application
    Filed: July 9, 2021
    Publication date: January 13, 2022
    Inventors: John Godsk NIELSEN, Torben Møller HANSEN
  • Patent number: 11143167
    Abstract: A method and apparatus for estimating a characteristic of a wind turbine electrical signal comprises buffering a sequence of sample values of the wind turbine electrical signal and a sequence of sample times corresponding with the sequence of sample values. The time periods represented by the sample times are variable. A sub-sequence of the buffered sample values to integrate is determined, based at least in part on a sum of the time periods. The characteristic is estimated by integrating the sample values in the sub-sequence.
    Type: Grant
    Filed: October 17, 2017
    Date of Patent: October 12, 2021
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Torsten Lund, John Godsk Nielsen
  • Patent number: 10958071
    Abstract: A method for operating a renewable energy power plant comprising a plurality of renewable energy generators. The method comprises: identifying a predetermined condition of the renewable energy power plant, of the grid, or of the connection between the renewable energy power plant and the grid, the predetermined condition indicating a weak grid interconnection between the renewable energy power plant and the grid; and controlling each renewable energy generator in an adaptive active power mode in response to recovery of the grid from a voltage deviation. The adaptive active power mode comprises: determining a thermal capacity of a chopper resistor of the renewable energy generator; calculating, based upon the determined thermal capacity, a limit level of rate of change of active power output that may be implemented by the renewable energy generator; and operating the renewable energy generator to output active power at the calculated rate of change limit level.
    Type: Grant
    Filed: November 20, 2018
    Date of Patent: March 23, 2021
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Manoj Gupta, Ravi Kumar, Janakiraman Sivasankaran, Thomas Schmidt Grau, Martin Ansbjerg Kjær, Kouroush Nayebi, John Godsk Nielsen, Jesper Sandberg Thomsen
  • Patent number: 10859064
    Abstract: A power conversion system for a wind turbine generator, comprising a machine-side converter having an AC voltage input from a generator and a DC voltage output to a DC link, wherein the machine-side converter is a modular multi-level converter comprising one or more converter legs corresponding to a respective one or more electrical phases of the generator, each of the converter legs comprising a plurality of converter cells, the system further comprising: a converter control module which provides the machine-side converter with a gate signal, and an electrical frequency estimation module configured to estimate the mean electrical frequency of the generator; wherein the gate signal has at least one mean switching frequency corresponding to at least one electrical phase of the generator; wherein the converter control module is configured to modulate the mean switching frequency of the gate signal in dependence on the mean electrical frequency of the generator.
    Type: Grant
    Filed: November 29, 2017
    Date of Patent: December 8, 2020
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Ciprian Biris, Duy Duc Doan, John Godsk Nielsen
  • Patent number: 10700624
    Abstract: A method of controlling a wind turbine generator (1) comprising an electrical generator (10) and a power converter (12), the power converter (12) comprising an electrical switch (14a, 14b) that is configured to process electrical power produced by the electrical generator (10), the method comprising: controlling an output from the electrical switch (14a, 14b) using a variable pulse-width modulated control signal, thereby to control characteristics of output power from the power converter (12); acquiring sample data (26) relating to an electronic signal within the wind turbine generator (1), wherein the sample data (26) is used for controlling the wind turbine generator (1); and dynamically adjusting a frequency (30) at which the sample data is acquired to synchronise data acquisition with a carrier frequency (24) of the control signal.
    Type: Grant
    Filed: August 11, 2017
    Date of Patent: June 30, 2020
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Gert Karmisholt Andersen, Kent Tange, Søren Andersen, Duy Duc Doan, Jens Peter Biltoft, Lars Helle, John Godsk Nielsen
  • Patent number: 10598701
    Abstract: A method for operating a power generation system coupled to a power grid during a grid unbalance event, a method for determining an injection current to be supplied into a power grid by a power generation system, and a method for addressing an asymmetric grid fault in a power grid connected to a power generation system are provided. The methods may be carried out based on a reactive or an active power/current priority.
    Type: Grant
    Filed: July 10, 2017
    Date of Patent: March 24, 2020
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Amit Kumar Gupta, John Godsk Nielsen, Liang Yang
  • Patent number: 10590914
    Abstract: A method, converter arrangement, and controller are disclosed for connecting an output of a converter with an electrical grid to control inrush currents into a grid filter assembly connected with the output of the converter, the electrical grid carrying an alternating current (AC) signal having one or more phases. The method includes determining a voltage of the AC signal and operating, after pre-charging a direct current (DC) link of the converter to a predetermined voltage, the converter using open-loop voltage control to produce an AC output signal that substantially matches the AC signal of the electrical grid. The open-loop voltage control is based on the determined voltage of the AC signal. The method further includes closing, after a predetermined amount of time of operating the converter using the open-loop voltage control, a switching device to thereby connect the output of the converter with the electrical grid.
    Type: Grant
    Filed: June 8, 2016
    Date of Patent: March 17, 2020
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Tusitha Abeyasekera, Duy Duc Doan, Gert Karmisholt Andersen, Lars Helle, Søren Andersen, Tune Pedersen, John Godsk Nielsen
  • Publication number: 20190369145
    Abstract: A method for operating a power generation system coupled to a power grid during a grid unbalance event, a method for determining an injection current to be supplied into a power grid by a power generation system, and a method for addressing an asymmetric grid fault in a power grid connected to a power generation system are provided. The methods may be carried out based on a reactive or an active power/current priority.
    Type: Application
    Filed: July 10, 2017
    Publication date: December 5, 2019
    Inventors: Amit Kumar GUPTA, John Godsk NIELSEN, Liang YANG
  • Publication number: 20190360470
    Abstract: A method and apparatus for estimating a characteristic of a wind turbine electrical signal comprises buffering a sequence of sample values of the wind turbine electrical signal and a sequence of sample times corresponding with the sequence of sample values. The time periods represented by the sample times are variable. A sub-sequence of the buffered sample values to integrate is determined, based at least in part on a sum of the time periods. The characteristic is estimated by integrating the sample values in the sub-sequence.
    Type: Application
    Filed: October 17, 2017
    Publication date: November 28, 2019
    Inventors: Torsten LUND, John Godsk NIELSEN