Patents by Inventor Duy Duc Doan

Duy Duc Doan 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: 11563385
    Abstract: This disclosure proposes a topology that integrates a DC chopper into the Modular Multilevel Converter (MMC) cells of a power converter. The integrated DC chopper may include chopper resistors that may also be advantageously integrated into a heat sink for a power module including at least the power transistors of the MMC cell. Embodiments herein also describe a method for using an MMC cell's IGBTs and chopper resistors for providing a safe discharge of both cell capacitors and DC-link capacitors in different operating conditions.
    Type: Grant
    Filed: December 27, 2021
    Date of Patent: January 24, 2023
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Ciprian Biris, Cem Özgür Gerçek, Lars Helle, Duy Duc Doan, Tune Pedersen
  • Patent number: 11502616
    Abstract: This invention concerns a method of controlling a line side converter of a power converter system operating in an over-modulation range. The line side converter comprises a controller comprising a feedback control module configured to output a feedback control signal for modifying a drive signal received by a modulator. The method comprises determining a modulation index within the over-modulation range; and, controlling the feedback control module to adjust the feedback control signal based on the modulation index.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: November 15, 2022
    Assignee: VESTAS WIND SYSIEMS A/S
    Inventors: Ciprian Biris, Kent Tange, Gert Karmisholt Andersen, Duy Duc Doan, Torsten Lund, Lars Meyer
  • Patent number: 11495967
    Abstract: This invention relates to a method of controlling at least one wind turbine of a plurality of wind turbines connected to an electrical grid at a predefined point in the electrical grid. The wind turbine comprises a DC link connecting a generator side converter to a line side converter, where the line side converter is controlled according to a modulation index requested by a power converter controller. The method comprises determining a harmonic frequency signal indicative of a harmonic frequency value at the predefined point in the electrical grid; determining a deviation between the harmonic frequency signal and a permissible harmonic frequency value; determining a permissible modulation index based on the deviation; comparing the permissible modulation index to the modulation index requested by the power converter controller; and, altering a DC link voltage set-point based on the comparison between the permissible modulation index and the requested modulation index.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: November 8, 2022
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Torsten Lund, Ciprian Biris, Kent Tange, Duy Duc Doan, Gert Karmisholt Andersen
  • Publication number: 20220123667
    Abstract: This disclosure proposes a topology that integrates a DC chopper into the Modular Multilevel Converter (MMC) cells of a power converter. The integrated DC chopper may include chopper resistors that may also be advantageously integrated into a heat sink for a power module comprising at least the power transistors of the MMC cell. Embodiments herein also describe a method for using an MMC cell's IGBTs and chopper resistors for providing a safe discharge of both cell capacitors and DC-link capacitors in different operating conditions.
    Type: Application
    Filed: December 27, 2021
    Publication date: April 21, 2022
    Inventors: Ciprian BIRIS, Cem Özgür GERÇEK, Lars HELLE, Duy Duc DOAN, Tune PEDERSEN
  • Patent number: 11286904
    Abstract: A method for use in controlling a wind turbine generator of a wind power plant based on a condition of a power converter or a component forming part of a power converter in the wind power plant. The method comprises determining the initial condition of the power converter or a component forming part of a power converter and determining the evolution of the condition from the initial condition based on notional power reference values of the wind turbine generator. The method further comprises comparing the evolution of the condition to a predetermined threshold and determining, from the comparison, a time period by which the condition of the power converter or a component forming part of a power converter will substantially equal the predetermined threshold.
    Type: Grant
    Filed: December 5, 2018
    Date of Patent: March 29, 2022
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Gert Karmisholt Andersen, Lars Helle, Poul Møhl Dyrlund, Morteza Rabi, Duy Duc Doan
  • Patent number: 11211878
    Abstract: A Direct Current (DC) chopper may be integrated into the Modular Multilevel Converter (MMC) cells of a power converter. The integrated DC chopper may include chopper resistors that may also be advantageously integrated into a heat sink for a power module including at least the power transistors of the MMC cell. The safe discharge of both cell capacitors and DC-link capacitors in different operating conditions is performed using Insulated-Gate Bipolar Transistors (IGBTs) and chopper resistors of an MMC cell.
    Type: Grant
    Filed: August 12, 2020
    Date of Patent: December 28, 2021
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Ciprian Biris, Cem Özgür Gerçek, Lars Helle, Duy Duc Doan, Tune Pedersen
  • Publication number: 20210376749
    Abstract: This invention concerns a method of controlling a line side converter of a power converter system operating in an over-modulation range. The line side converter comprises a controller comprising a feedback control module configured to output a feedback control signal for modifying a drive signal received by a modulator. The method comprises determining a modulation index within the over-modulation range; and, controlling the feedback control module to adjust the feedback control signal based on the modulation index.
    Type: Application
    Filed: September 11, 2019
    Publication date: December 2, 2021
    Inventors: Ciprian BIRIS, Kent TANGE, Gert Karmishoit ANDERSEN, Duy Duc DOAN, Torsten LUND, Lars MEYER
  • Publication number: 20210351714
    Abstract: This invention concerns a method of controlling a power converter system 26 operating in an overmodulation region. The power converter system 26 comprises more than two current controllers 71, 73, 77, 79 a modulator 76 and a power converter 78, and the modulator 76 is configured to provide at least one modulated drive signal 87 to the power converter 78 based on voltage reference vector signals 82a, 82b, 82c, 82d from the more than two current controllers 71, 73, 77, 79. The method comprises determining the voltage reference vector signals 82a, 82b, 82c, 82d; determining compensated voltage reference vector signals 84a, 84b, 84c, 84d indicative of a fundamental frequency of a respective voltage reference vector signal 82a, 82b, 82c, 82d; and, determining the at least one modulated drive signal 87 based on a combination of the compensated voltage reference vector signals 84a, 84b, 84c, 84d.
    Type: Application
    Filed: September 19, 2019
    Publication date: November 11, 2021
    Inventors: Ciprian BIRIS, Kent TANGE, Duy Duc DOAN, Gert Karmisholt ANDERSEN, Torsten LUND, Lars MEYER
  • Publication number: 20210050796
    Abstract: This disclosure proposes a topology that integrates a DC chopper into the Modular Multilevel Converter (MMC) cells of a power converter. The integrated DC chopper may include chopper resistors that may also be advantageously integrated into a heat sink for a power module comprising at least the power transistors of the MMC cell. Embodiments herein also describe a method for using an MMC cell's IGBTs and chopper resistors for providing a safe discharge of both cell capacitors and DC-link capacitors in different operating conditions.
    Type: Application
    Filed: August 12, 2020
    Publication date: February 18, 2021
    Inventors: Ciprian BIRIS, Cem Özgür GERÇEK, Lars HELLE, Duy Duc DOAN, Tune PEDERSEN
  • Publication number: 20200392942
    Abstract: A method for use in controlling a wind turbine generator of a wind power plant based on a condition of a power converter or a component forming part of a power converter in the wind power plant. The method comprises determining the initial condition of the power converter or a component forming part of a power converter and determining the evolution of the condition from the initial condition based on notional power reference values of the wind turbine generator. The method further comprises comparing the evolution of the condition to a predetermined threshold and determining, from the comparison, a time period by which the condition of the power converter or a component forming part of a power converter will substantially equal the predetermined threshold.
    Type: Application
    Filed: December 5, 2018
    Publication date: December 17, 2020
    Inventors: Gert Karmisholt ANDERSEN, Lars HELLE, Poul Møhl DYRLUND, Morteza RABI, Duy Duc DOAN
  • 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: 10774809
    Abstract: Controlling a power converters during over voltage condition. A wind turbine signal is monitored for detection of an over voltage of the grid and upon detection of the over voltage, an over-modulation mode is initiated wherein the grid side converter is operated with a modulation index being increased in an over-modulation range at least during a sub-period of the over-modulation mode, and upon the detection of the operational condition, a DC-voltage adjustment mode is initiated wherein the DC voltage of the DC link is decreased from a second voltage level towards a first voltage level at least during a sub-period of the DC-voltage adjustment mode.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: September 15, 2020
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Ciprian Biris, Kent Tange, Duy Duc Doan, Torsten Lund, Gert Karmisholt Andersen
  • 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: 10601310
    Abstract: A power generation system, wind turbine, and method of pulse width modulation (PWM) for power converters are disclosed. The method generally includes generating a substantially random distribution of timing values, applying a filter to the random distribution to produce a modified random distribution, and delivering PWM timing signals based on the modified random distribution to the power converters.
    Type: Grant
    Filed: November 11, 2015
    Date of Patent: March 24, 2020
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Søren Andersen, Duy Duc Doan, Gert Karmisholt Andersen, Thomas Drljevic-Nielsen
  • 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
  • Patent number: 10483865
    Abstract: A wind turbine generator 1 supplies three-phase a.c. current of variable voltage and variable frequency to two pairs of rectifiers 4a, 4b and 4c, 4d which generate respective d.c. outputs connected to positive, negative and neutral d.c. conductors 6, 7, 8. The outputs from each pair of rectifiers are connected together, and the outputs from the two pairs are connected in series to create a high-voltage d.c. output. Inverters 10a, 10b, 10c, 10d then convert the d.c. power to a.c. at a fixed frequency and voltage suitable for connection to the mains grid. To reduce the effect of common-mode noise, a capacitor is connected between the 1 neutral conductor 7 and earth, and a respective filter circuit 30 is connected between each of the a.c. outputs of the inverters 10a, 10b, 10c, 10d and earth. To reduce the effect of voltage surges during lightning, a surge protection device is also connected between the neutral d.c. conductor 7 and earth.
    Type: Grant
    Filed: October 14, 2014
    Date of Patent: November 19, 2019
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Tusitha Abeyasekera, Duy Duc Doan, Lars Helle, Allan Holm Jørgensen, John Godsk Nielsen, Søren Andersen
  • Publication number: 20190338753
    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: Application
    Filed: November 29, 2017
    Publication date: November 7, 2019
    Inventors: Ciprian BIRIS, Duy Duc DOAN, John Godsk NIELSEN
  • Patent number: 10359025
    Abstract: The present invention relates to a method for shutting down a wind power facility, said wind power facility comprising a power generator, a power converter comprising generator side and grid side converters being separated by an intermediate DC circuit, and power dissipation or power storage means being operatively connected to the intermediate DC circuit, the method comprising the steps of determining that the wind power facility needs to be shut down, and operating the generator side converter in accordance with a load time curve during shutdown of the wind power facility in order to avoid overloading of selected generator side converter components and the power dissipation or power storage means. Moreover, the present invention relates to a wind power facility for performing this method.
    Type: Grant
    Filed: July 2, 2015
    Date of Patent: July 23, 2019
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Duy Duc Doan, John Godsk Nielsen, Per Bisgaard
  • Publication number: 20190219029
    Abstract: Controlling a power converters during over voltage condition. A wind turbine signal is monitored for detection of an over voltage of the grid and upon detection of the over voltage, an over-modulation mode is initiated wherein the grid side converter is operated with a modulation index being increased in an over-modulation range at least during a sub-period of the over-modulation mode, and upon the detection of the operational condition, a DC-voltage adjustment mode is initiated wherein the DC voltage of the DC link is decreased from a second voltage level towards a first voltage level at least during a sub-period of the DC-voltage adjustment mode.
    Type: Application
    Filed: September 27, 2018
    Publication date: July 18, 2019
    Inventors: Ciprian BIRIS, Kent TANGE, Duy Duc DOAN, Torsten LUND, Gert Karmisholt ANDERSEN
  • Publication number: 20190181787
    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: Application
    Filed: August 11, 2017
    Publication date: June 13, 2019
    Inventors: Gert Karmisholt ANDERSEN, Kent TANGE, Søren ANDERSEN, Duy Duc DOAN, Jens Peter BILTOFT, Lars HELLE, John Godsk NIELSEN