Patents by Inventor Drazen Dujic

Drazen Dujic 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).

  • Publication number: 20250070773
    Abstract: The invention relates to a gate unit (22) for controlling a gate commutated thyristor (21), comprising: —a voltage selector (26) for selectively applying a high supply potential (Vpos), a middle supply potential (Vmid), and a low supply potential (Vneg); —a nonlinear inductor (27) serially coupled between the output of the voltage selector (26); —a gate control unit (23) configured to control the voltage selector (26) to control switching of the gate commutated thyristor (21) in its turn-on state comprising a turn-on pulse generation, a positive-gate-voltage backporch operation, a negative-gate-voltage backporch operation and a retrigger pulse generation; wherein the nonlinear inductor (27) has a nonlinearity to have a high inductance during any of the backporch operations and to have a low inductance during the turn-on pulse generation and retrigger pulse generation.
    Type: Application
    Filed: October 26, 2022
    Publication date: February 27, 2025
    Applicant: ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE (EPFL)
    Inventors: Jakub KUCKA, Drazen DUJIC
  • Publication number: 20240266963
    Abstract: The present invention relates to a method for operating a resonant power converter. The resonant power converter has a primary stage and a secondary stage, at least one of which is actively operated and includes a half-bridge or full-bridge inverter having a pull-up switching device, coupled in parallel with a pull-up antiparallel diode and a pull-down switching device, coupled in parallel with a pull-down antiparallel diode, comprising the steps of alternately turning-off and turning on the pull-up and pull-down switching devices according to a periodic switching scheme, wherein after turning-off one of the switching devices the complementary switching device is respectively turned on after a delay time; and initiating an error handling, if after turning-off of one of the switching devices a non-conductance state of the antiparallel diode of the complementary switching device has been determined.
    Type: Application
    Filed: August 9, 2022
    Publication date: August 8, 2024
    Applicant: ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE (EPFL)
    Inventors: Drazen Dujic, Jakub Kucka
  • Publication number: 20240079966
    Abstract: The present disclosure provides a power converter, comprising: a positive terminal, a neutral terminal, a negative terminal, a first intermediate node, a second intermediate node, and an AC terminal. Vertical and horizontal switches are configured to switch a DC voltage between the positive and negative terminal to an AC voltage at the AC terminal. The AC voltage comprises three main voltage levels. A transition between any two of the main voltage levels follow a trapezoidal shape with at least one voltage sub-level.
    Type: Application
    Filed: November 10, 2023
    Publication date: March 7, 2024
    Inventors: Peng Shuai, Chengmin Li, Drazen Dujic
  • Publication number: 20240079967
    Abstract: The present disclosure relates to a quasi-multi-level power converter and a method of operating the same. The power converter is capable of reconciling scalable operation voltage, multiple output voltage levels, controllable voltage rising or decreasing slew rate, and a balance between the high voltage levels and the volume/weight of passive circuit components.
    Type: Application
    Filed: November 12, 2023
    Publication date: March 7, 2024
    Inventors: Peng Shuai, Chengmin Li, Drazen Dujic
  • Publication number: 20230378880
    Abstract: The present invention relates to a DC/DC converter (1) for transferring an active power between two DC subsystems (5, 6) comprising: —a first converter stage (3) and a second converter stage (4) both configured to be selectively operated as an active inverter or as a passive rectifier; —an AC coupling circuit (2) for coupling the first and the second converter stage (3, 4) by means of an AC power transfer; and —a control unit (10) configured to switch the operation mode of the first and second converter stages (3, 4) depending on a measurement of an amount of power transfer through the AC coupling circuit (2).
    Type: Application
    Filed: September 21, 2021
    Publication date: November 23, 2023
    Inventors: Jakub KUCKA, Drazen DUJIC
  • Patent number: 10374431
    Abstract: A converter system for interconnecting renewable energy sources with a DC distribution bus comprises a converter unit which comprises an isolated DC-to-DC converter connectable to the renewable energy source, and a non-isolated DC-to-DC converter connectable to the DC distribution bus, which is cascade connected with the isolated DC-to-DC converter.
    Type: Grant
    Filed: January 17, 2017
    Date of Patent: August 6, 2019
    Assignee: ABB Schweiz AG
    Inventors: Francisco Canales, Frederick Kieferndorf, Drazen Dujic
  • Publication number: 20170126010
    Abstract: A converter system for interconnecting renewable energy sources with a DC distribution bus comprises a converter unit which comprises an isolated DC-to-DC converter connectable to the renewable energy source, and a non-isolated DC-to-DC converter connectable to the DC distribution bus, which is cascade connected with the isolated DC-to-DC converter.
    Type: Application
    Filed: January 17, 2017
    Publication date: May 4, 2017
    Inventors: Francisco Canales, Frederick Kieferndorf, Drazen Dujic
  • Publication number: 20150180352
    Abstract: A modular converter is disclosed which includes plural converter cells connected in series on a first side, and connected on a second side, wherein each converter cell includes an AC-to-DC converter connected to the first side and a DC-to-DC converter connected to the second side. Exemplary embodiments estimate power transferred by the modular converter; compare the transferred power with a threshold value; when the transferred power exceeds the threshold value, operate in a normal load operation mode; when the transferred power is below the threshold value, operate in a low load operation mode with reduced switching losses.
    Type: Application
    Filed: March 4, 2015
    Publication date: June 25, 2015
    Applicant: ABB Technology AG
    Inventors: Akos MESTER, Drazen DUJIC, Thomas BESSELMANN
  • Publication number: 20140313789
    Abstract: A distributed controller module for controlling a power electronics building block of a power electronics converter includes a plurality of gate drivers for controlling power electronics switches of the power electronics building block, a first fiber optics communication interface for communication with a central controller module, a second fiber optics communication interface for communication with a second distributed controller module for controlling a second power electronics building block of the power electronics converter, and a processor unit for controlling the gate drivers and transmitting and receiving data via the first fiber optics communication interface and the second fiber optics communication interface.
    Type: Application
    Filed: April 23, 2014
    Publication date: October 23, 2014
    Applicant: ABB Technology AG
    Inventors: Drazen DUJIC, Akos Mester, Roberto Celli
  • Patent number: 8848409
    Abstract: A converter includes an active stage for converting an AC input voltage at an AC input into an intermediate DC voltage, and a DC/DC converter for transforming the intermediate DC voltage into an output DC voltage at a DC output. The DC/DC converter has a resonant transformer formed by a resonant circuit and a transformer. The converter also includes control unit configured to actively operate the active stage only based on an output DC voltage of the DC/DC converter, an input voltage, and an input current of the converter, and to operate the DC/DC converter in an open loop mode. A method for operating such a converter is also provided.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: September 30, 2014
    Assignee: ABB Technology AG
    Inventors: Drazen Dujic, Francisco Canales, Akos Mester
  • Publication number: 20130063981
    Abstract: A converter includes an active stage for converting an AC input voltage at an AC input into an intermediate DC voltage, and a DC/DC converter for transforming the intermediate DC voltage into an output DC voltage at a DC output. The DC/DC converter has a resonant transformer formed by a resonant circuit and a transformer. The converter also includes control unit configured to actively operate the active stage only based on an output DC voltage of the DC/DC converter, an input voltage, and an input current of the converter, and to operate the DC/DC converter in an open loop mode. A method for operating such a converter is also provided.
    Type: Application
    Filed: September 7, 2012
    Publication date: March 14, 2013
    Applicant: ABB Technology AG
    Inventors: Drazen Dujic, Francisco Canales, Akos Mester