Patents by Inventor Beat BUCHMANN
Beat BUCHMANN 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).
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Patent number: 11695318Abstract: A method performed by a control system of a power electronics converter. A first part of a grid-side current controller runs a first feedback control algorithm having a first control cycle time and includes at least proportional control using a proportional gain. A third part of the controller runs a third feedback control algorithm having the first control cycle time and acting on an output from the first control algorithm after SOA limits have been applied and includes counteracting the proportional control of the first feedback control algorithm. A second part of the controller runs a second feedback control algorithm having a second control cycle time, less than the first control cycle time, and acting on an output from the third control algorithm with the same polarity as the first control algorithm and includes proportional control using the proportional gain.Type: GrantFiled: September 3, 2018Date of Patent: July 4, 2023Assignee: Hitachi Energy Switzerland AGInventors: Xinhua Ke, Beat Buchmann
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Publication number: 20210328495Abstract: A method performed by a control system of a power electronics converter. A first part of a grid-side current controller runs a first feedback control algorithm having a first control cycle time and includes at least proportional control using a proportional gain. A third part of the controller runs a third feedback control algorithm having the first control cycle time and acting on an output from the first control algorithm after SOA limits have been applied and includes counteracting the proportional control of the first feedback control algorithm. A second part of the controller runs a second feedback control algorithm having a second control cycle time, less than the first control cycle time, and acting on an output from the third control algorithm with the same polarity as the first control algorithm and includes proportional control using the proportional gain.Type: ApplicationFiled: September 3, 2018Publication date: October 21, 2021Inventors: Xinhua Ke, Beat Buchmann
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Patent number: 10855199Abstract: A method of discharging a Modular Multilevel Converter (MMC) includes a plurality of phase legs connected in delta configuration. Each leg includes a plurality of series connected submodules, each submodule including an energy storage. The method includes disconnecting the MMC from an electrical grid, discharging the energy storages by means of a circulating current, and reconnecting the MMC to the electrical grid. The discharging includes, for each phase leg, setting a voltage reference, and sequentially selecting submodules in zero state by means of a sorting algorithm for switching each of the selected submodules to plus or minus state until the voltage deviation from the set voltage reference of the energy storage of each submodule in the phase leg is within a predefined range.Type: GrantFiled: December 18, 2015Date of Patent: December 1, 2020Assignee: ABB Power Grids Switzerland AGInventors: Beat Buchmann, Jerome Fischer
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Patent number: 10840822Abstract: A method of controlling a Modular Multilevel Converter (MMC) during a fault in a power grid to which the MMC is connected is disclosed. The MMC includes a plurality of phases, each including at least one phase leg. Each phase leg includes a plurality of series connected converter cells. The method includes determining that a fault has occurred in the power grid, the fault including a reduced voltage in the power grid. The method also includes, for each phase leg of the MMC, reducing the DC voltage of the phase leg by a predetermined amount from a nominal DC voltage to a reduced DC voltage, the DC voltage being the sum of all respective voltages over an energy storage of each cell of the phase leg. The method also includes determining that the fault has been cleared, whereby the voltage in the power grid is returned to nominal. The method also includes for each of the phase legs of the MMC, increasing the DC voltage back to the nominal DC voltage.Type: GrantFiled: June 21, 2017Date of Patent: November 17, 2020Assignee: ABB Schweiz AGInventors: Beat Buchmann, Cosmin Banceanu
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Publication number: 20200177098Abstract: A method of controlling a Modular Multilevel Converter (MMC) during a fault in a power grid to which the MMC is connected is disclosed. The MMC includes a plurality of phases, each including at least one phase leg. Each phase leg includes a plurality of series connected converter cells. The method includes determining that a fault has occurred in the power grid, the fault including a reduced voltage in the power grid. The method also includes, for each phase leg of the MMC, reducing the DC voltage of the phase leg by a predetermined amount from a nominal DC voltage to a reduced DC voltage, the DC voltage being the sum of all respective voltages over an energy storage of each cell of the phase leg. The method also includes determining that the fault has been cleared, whereby the voltage in the power grid is returned to nominal. The method also includes for each of the phase legs of the MMC, increasing the DC voltage back to the nominal DC voltage.Type: ApplicationFiled: June 21, 2017Publication date: June 4, 2020Applicant: ABB Schweiz AGInventors: Beat BUCHMANN, Cosmin BANCEANU
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Patent number: 10651755Abstract: The present invention proposes a hybrid converter branch operating mode for a Modular Multilevel power Converter MMC with MMC cells in distinct subsets operating according to a “pulse blocked” cell operation mode with DC cell voltage increase or according to a “bypass” cell operation mode without DC cell voltage increase. Repeated cell subset assignment and corresponding alternation of cell operating mode allows to reduce or at least manage a mean deviation of the cell capacitor DC voltages of the converter cells. The invention also reduces no-load losses of the MMC in standby mode and a charging voltage in an MMC charging mode.Type: GrantFiled: June 8, 2017Date of Patent: May 12, 2020Assignee: ABB Schweiz AGInventors: Simon Herold, Beat Buchmann
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Patent number: 10622913Abstract: A modular cell for a phase leg of a Modular Multilevel power Converter (MMC) is disclosed. The cell includes a power storing device, a plurality of semiconductor switches, a cell controller, and a current sensor. The current sensor is connected between a current conducting line in the cell and the cell controller for measuring a current through the cell and signaling information about the measured current to the cell controller. The cell controller includes an optical communication interface and is configured for forwarding the information about the measured current to a higher level controller over the optical communication interface.Type: GrantFiled: June 1, 2016Date of Patent: April 14, 2020Assignee: ABB Schweiz AGInventors: Beat Buchmann, Simon Herold
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Publication number: 20190334453Abstract: A modular cell for a phase leg of a Modular Multilevel power Converter (MMC) is disclosed. The cell includes a power storing device, a plurality of semiconductor switches, a cell controller, and a current sensor. The current sensor is connected between a current conducting line in the cell and the cell controller for measuring a current through the cell and signaling information about the measured current to the cell controller. The cell controller includes an optical communication interface and is configured for forwarding the information about the measured current to a higher level controller over the optical communication interface.Type: ApplicationFiled: June 1, 2016Publication date: October 31, 2019Inventors: Beat Buchmann, Simon Herold
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Publication number: 20190288509Abstract: A method of discharging a Modular Multilevel Converter (MMC) includes a plurality of phase legs connected in delta configuration. Each leg includes a plurality of series connected submodules, each submodule including an energy storage. The method includes disconnecting the MMC from an electrical grid, discharging the energy storages by means of a circulating current, and reconnecting the MMC to the electrical grid. The discharging includes, for each phase leg, setting a voltage reference, and sequentially selecting submodules in zero state by means of a sorting algorithm for switching each of the selected submodules to plus or minus state until the voltage deviation from the set voltage reference of the energy storage of each submodule in the phase leg is within a predefined range.Type: ApplicationFiled: December 18, 2015Publication date: September 19, 2019Applicant: ABB SCHWEIZ AGInventors: Beat BUCHMANN, Jerome FISCHER
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Publication number: 20170271997Abstract: The present invention proposes a hybrid converter branch operating mode for a Modular Multilevel power Converter MMC with MMC cells in distinct subsets operating according to a “pulse blocked” cell operation mode with DC cell voltage increase or according to a “bypass” cell operation mode without DC cell voltage increase. Repeated cell subset assignment and corresponding alternation of cell operating mode allows to reduce or at least manage a mean deviation of the cell capacitor DC voltages of the converter cells. The invention also reduces no-load losses of the MMC in standby mode and a charging voltage in an MMC charging mode.Type: ApplicationFiled: June 8, 2017Publication date: September 21, 2017Inventors: Simon Herold, Beat Buchmann
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Patent number: 8908398Abstract: A method for operating a converter circuit is provided. The converter circuit includes a converter unit and a transformer. The transformer includes at least one winding set with a primary winding and a secondary winding. The converter unit is connected, on the AC voltage side, to the primary winding of the respective winding set. In order to compensate for undesirable saturation of the transformer, the converter unit is used to deliberately apply a DC voltage to the primary winding of the respective winding set of the transformer.Type: GrantFiled: December 2, 2011Date of Patent: December 9, 2014Assignee: ABB Technology AGInventors: Beat Buchmann, Beat Ronner
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Publication number: 20120140535Abstract: A method for operating a converter circuit is provided. The converter circuit includes a converter unit and a transformer. The transformer includes at least one winding set with a primary winding and a secondary winding. The converter unit is connected, on the AC voltage side, to the primary winding of the respective winding set. In order to compensate for undesirable saturation of the transformer, the converter unit is used to deliberately apply a DC voltage to the primary winding of the respective winding set of the transformer.Type: ApplicationFiled: December 2, 2011Publication date: June 7, 2012Applicant: ABB Technology AGInventors: Beat BUCHMANN, Beat RONNER