Patents by Inventor Seung Ki Sul

Seung Ki Sul 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: 20210067075
    Abstract: A method for estimating a magnet temperature of a rotor magnet within a rotary electric machine includes, while a rotor of the electric machine is stationary, injecting a high-frequency voltage component onto a control voltage of the electric machine, via a controller, to generate an adjusted voltage command, and extracting a high-frequency component of a resulting current as an extracted high-frequency component. The method also includes calculating an inductance value of the electric machine using the extracted high-frequency component of the resulting current. The magnet temperature is estimated using the calculated inductance value and an angular position of the rotor. The method includes controlling an operation of the electric machine using the estimated magnet temperature. An electric powertrain uses the electric machine and controller noted above.
    Type: Application
    Filed: September 4, 2019
    Publication date: March 4, 2021
    Applicants: GM GLOBAL TECHNOLOGY OPERATIONS LLC, Seoul National University R & DB Foundation
    Inventors: Daniel J. Berry, Anno Yoo, Seung Ki Sul, Hyun-Sam Jung
  • Publication number: 20210036646
    Abstract: Embodiments relate to a motor simulator for an inverter under test (IUT), the motor simulator comprising: a voltage follower inverter for at least partially cancelling an output voltage of the IUT; and an output current control unit for controlling an output current of the IUT on the basis of an estimated current of a simulation target motor.
    Type: Application
    Filed: October 15, 2018
    Publication date: February 4, 2021
    Inventors: Seung-Ki Sul, Yong-Cheol Kwon, Yoon-Ro Lee
  • Publication number: 20200366228
    Abstract: A motor control apparatus according to one embodiment of the present invention comprises: a current controller for generating a voltage command signal on the basis of a torque command for driving a motor and a fundamental wave current of the motor; a high frequency voltage generator for generating a high frequency voltage signal for injection into the voltage command signal; an inverter for applying a voltage to the motor on the basis of the voltage command signal and the high frequency voltage signal; an angle estimator for generating an estimated angle of a rotor of the motor on an estimated coordinate system on the basis of a current signal of the motor; and a compensator for adding a first compensation signal (icomp) to the current signal (isig), wherein the first compensation signal (icomp) may be related to the torque command and the estimated angle.
    Type: Application
    Filed: September 19, 2018
    Publication date: November 19, 2020
    Inventors: Seung-Ki Sul, Yong-Cheol Kwon, Joohyun Lee
  • Publication number: 20200228028
    Abstract: A unit power cell of an inverter system, according to one embodiment of the present invention, comprises: a first leg including first and fourth switching elements, which are connected in series to each other, second and third switching elements, which are connected in series with each other between a connection point of the first and second switching elements and a smoothing unit, and first, second, third and fourth diodes, which are inversely and respectively connected in parallel with the first, second, third and fourth switching elements; and a second leg connected in parallel with the first leg and including fifth and sixth switching elements, which are connected in series to each other, and fifth and sixth diodes, which are inversely and respectively connected in parallel with the fifth and sixth switching elements.
    Type: Application
    Filed: July 18, 2018
    Publication date: July 16, 2020
    Inventors: Sung-Guk AHN, Seung-Ki SUL, Hyun-Sam JUNG, Jeong-Mock YOO
  • Patent number: 10164435
    Abstract: A reactive power compensator includes a plurality of phase clusters each including plurality of cells and a controller configured to control the plurality of phase clusters. The controller performs control to generate an offset signal through phasor transformation based on respective voltage values and current values of the plurality of phase clusters and to compensate for energy errors between the plurality of phase clusters based on the generated offset signal.
    Type: Grant
    Filed: January 12, 2018
    Date of Patent: December 25, 2018
    Assignee: LSIS CO., LTD.
    Inventors: Yong Ho Chung, Gum Tae Son, Seung Ki Sul, Jae Jung Jung, Joon Hee Lee
  • Patent number: 10122173
    Abstract: A reactive power compensator includes a plurality of phase clusters each including a plurality of cells, and a controller configured to control the plurality of phase clusters. When an energy error is generated in each of the plurality of phase clusters, the controller performs control to compensate for the energy error by generating an offset signal having a zero sequence component based on an error energy value of each of the plurality of phase clusters.
    Type: Grant
    Filed: June 7, 2017
    Date of Patent: November 6, 2018
    Assignee: LSIS CO., LTD.
    Inventors: Yong Ho Chung, Gum Tae Son, Seung Ki Sul, Jae Jung Jung, Joon Hee Lee
  • Publication number: 20180212430
    Abstract: A reactive power compensator includes a plurality of phase clusters each including plurality of cells and a controller configured to control the plurality of phase clusters. The controller performs control to generate an offset signal through phasor transformation based on respective voltage values and current values of the plurality of phase clusters and to compensate for energy errors between the plurality of phase clusters based on the generated offset signal.
    Type: Application
    Filed: January 12, 2018
    Publication date: July 26, 2018
    Inventors: Yong Ho CHUNG, Gum Tae SON, Seung Ki SUL, Jae Jung JUNG, Joon Hee LEE
  • Publication number: 20180205228
    Abstract: A reactive power compensator includes a plurality of phase clusters each including a plurality of cells, and a controller configured to control the plurality of phase clusters. When an energy error is generated in each of the plurality of phase clusters, the controller performs control to compensate for the energy error by generating an offset signal having a zero sequence component based on an error energy value of each of the plurality of phase clusters.
    Type: Application
    Filed: June 7, 2017
    Publication date: July 19, 2018
    Applicants: LSIS CO., LTD., Seoul National University R&DB FOUNDATION
    Inventors: Yong Ho CHUNG, Gum Tae SON, Seung Ki SUL, Jae Jung JUNG, Joon Hee LEE
  • Publication number: 20180183336
    Abstract: Disclosed herein is an apparatus for controlling DC link voltage in power cells of a medium-voltage inverter. The apparatus controls DC link voltage in single-phase I/O power cells in the medium-voltage inverter, by way of using a first average power based on a positive sequence voltage and a positive sequence current to output a first DC link voltage reference for controlling the average value of the DC link voltages, and using a second average power based on a negative sequence voltage and a positive sequence current or a positive sequence voltage and a negative sequence current to output a second DC link voltage reference for controlling an interphase DC link voltage.
    Type: Application
    Filed: November 1, 2017
    Publication date: June 28, 2018
    Inventors: Jong-Je PARK, Seung-Ki SUL, Jeong-Mock YOO, Hyun-Sam JUNG
  • Patent number: 10008937
    Abstract: Disclosed herein is an apparatus for controlling DC link voltage in power cells of a medium-voltage inverter. The apparatus controls DC link voltage in single-phase I/O power cells in the medium-voltage inverter, by way of using a first average power based on a positive sequence voltage and a positive sequence current to output a first DC link voltage reference for controlling the average value of the DC link voltages, and using a second average power based on a negative sequence voltage and a positive sequence current or a positive sequence voltage and a negative sequence current to output a second DC link voltage reference for controlling an interphase DC link voltage.
    Type: Grant
    Filed: November 1, 2017
    Date of Patent: June 26, 2018
    Assignee: LSIS CO., LTD.
    Inventors: Jong-Je Park, Seung-Ki Sul, Jeong-Mock Yoo, Hyun-Sam Jung
  • Patent number: 9954475
    Abstract: A motor driving apparatus includes a rectifying circuit to rectify an AC power supplied from an external AC power source, one pair of film capacitors to output a DC voltage and a neutral point voltage by removing a ripple of a voltage rectified by the AC-DC conversion unit, a 3-level inverter to supply a driving current to a motor using the DC voltage applied from the DC link unit, and a control module to control the 3-level inverter. The control module includes a motor speed control module to control the rotation of the motor, a DC voltage control module to stabilize the DC voltage, a neutral point voltage control module to stabilize the neutral point voltage, and a stabilizing voltage limiting module to control the DC voltage control module and the neutral point voltage control module according to an output of the motor speed control module.
    Type: Grant
    Filed: March 14, 2016
    Date of Patent: April 24, 2018
    Assignees: SAMSUNG ELECTRONICS CO., LTD., SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION
    Inventors: Je Hyung Cho, Seung-Ki Sul, Se Hwa Choe, Han Sol Seo
  • Publication number: 20180083550
    Abstract: The present disclosure relates a modular multi-level converter (MMC) including two arms including different types of sub modules according to the respective arms, two sub controllers corresponding to the two arms, respectively and configured to separately control the two arms, respectively, and a central controller configured to determine a switching operation condition of the sub module and to output a switching signal corresponding to the switching operation condition to each of the two sub controllers, wherein the two sub controllers control the respective corresponding arms based on the switching signal and, upon receiving a voltage change switching signal for controlling a voltage applied to one of the two arms, change the voltage applied to one of the two arms based on the voltage change switching signal.
    Type: Application
    Filed: March 30, 2017
    Publication date: March 22, 2018
    Inventors: Yong-Ho CHUNG, Gum-Tae SON, Seung-KI SUL, Jae-Jung JUNG, Sheng-hui CUI
  • Patent number: 9819294
    Abstract: An inverter control apparatus and a control method thereof are provided. The inverter control apparatus and a control method thereof stably operate a three-phase motor using a capacitor having a small capacitance for a DC link. The inverter control apparatus includes a current sensor to sense an output current of the inverter, a voltage sensor to sense a DC-link voltage of the inverter, and a controller to generate an average of a periodically varying rotor based q-axis current boundary value based on the output current and the DC-link voltage to generate a current reference on the basis of the average of the rotor based q-axis current boundary value, and to drive a three-phase motor based on the current reference. Stabilized variable speed control of a motor by using a small-capacitance capacitor for a DC link of an inverter is performed and reliability of an inverter circuit improved.
    Type: Grant
    Filed: September 2, 2015
    Date of Patent: November 14, 2017
    Assignees: SAMSUNG ELECTRONICS CO., LTD., SNU R&DB FOUNDATION
    Inventors: Young Jae Park, Han Sol Seo, Bodrov Alexey, Seung Ki Sul, Hyun-Sam Jung, Seung-Jun Chee
  • Publication number: 20160268950
    Abstract: A motor driving apparatus includes a rectifying circuit to rectify an AC power supplied from an external AC power source, one pair of film capacitors to output a DC voltage and a neutral point voltage by removing a ripple of a voltage rectified by the AC-DC conversion unit, a 3-level inverter to supply a driving current to a motor using the DC voltage applied from the DC link unit, and a control module to control the 3-level inverter. The control module includes a motor speed control module to control the rotation of the motor, a DC voltage control module to stabilize the DC voltage, a neutral point voltage control module to stabilize the neutral point voltage, and a stabilizing voltage limiting module to control the DC voltage control module and the neutral point voltage control module according to an output of the motor speed control module.
    Type: Application
    Filed: March 14, 2016
    Publication date: September 15, 2016
    Inventors: Je Hyung Cho, Seung-Ki Sul, Se Hwa Choe, Han Sol Seo
  • Publication number: 20160134217
    Abstract: A motor includes a stator and a rotor that is arranged opposite to the stator through a predetermined air gap. The stator is such that a plurality of coils are wound around respective slots for each of a plurality of phases. In the stator, the number of turns of one of the plurality of coils is different from those of the others for each of the phases. In the rotor, among a plurality of magnetic poles formed of a plurality of permanent magnets arranged in a circumferential direction of a core, a magnetoresistance of at least one magnetic pole is different from those of the others.
    Type: Application
    Filed: January 20, 2016
    Publication date: May 12, 2016
    Applicants: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Shinya MORIMOTO, Sohji MURAKAMI, Noor Aamir BALOCH, Motomichi OHTO, Yong-Cheol KWON, Seung-Ki SUL
  • Patent number: 9257933
    Abstract: A single external power supply variable speed induction motor and a control method thereof are disclosed. An induction motor includes: a stator in which coils directly connected to a single-phase or 3-phase or more systematic power supply are wound; a rotor that is supported to be rotatable in the stator; a power conversion device that is attached to the rotor and controls a rotor current without connection of a separate external power supply; and a control circuit that is connected to the power conversion device and controls the power conversion device.
    Type: Grant
    Filed: August 29, 2012
    Date of Patent: February 9, 2016
    Assignee: SNU R&DB FOUNDATION
    Inventors: Jung Ik Ha, Sung Min Kim, Seung Ki Sul, Yong Su Han
  • Publication number: 20150381095
    Abstract: An inverter control apparatus and a control method thereof are provided. The inverter control apparatus and a control method thereof stably operate a three-phase motor using a capacitor having a small capacitance for a DC link. The inverter control apparatus includes a current sensor to sense an output current of the inverter, a voltage sensor to sense a DC-link voltage of the inverter, and a controller to generate an average of a periodically varying rotor based q-axis current boundary value based on the output current and the DC-link voltage to generate a current reference on the basis of the average of the rotor based q-axis current boundary value, and to drive a three-phase motor based on the current reference. Stabilized variable speed control of a motor by using a small-capacitance capacitor for a DC link of an inverter is performed and reliability of an inverter circuit improved.
    Type: Application
    Filed: September 2, 2015
    Publication date: December 31, 2015
    Applicants: SAMSUNG ELECTRONICS CO., LTD., SNU R&DB FOUNDATION
    Inventors: Young Jae PARK, Han Sol Seo, Bodrov Alexey, Seung Ki Sul, Hyun-Sam Jung, Seung-Jun Chee
  • Patent number: 9209707
    Abstract: A three-level inverter having two direct current (DC)-links for converting DC voltages generated in a plurality of photovoltaic (PV) modules into alternating current (AC) voltages, wherein one end of a first DC-link of the two DC-links is connected to a first potential point at which a first potential is generated in the plurality of PV modules, and one end of a second DC-link of the two DC-links is connected to a second potential point at which a second potential that is lower than the first potential is generated in the plurality of PV modules, and both the other end of the first DC-link and the other end of the second DC-link are connected to a third potential point at which a third potential having a medium level between the first potential and the second potential is generated in the plurality of PV modules.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: December 8, 2015
    Assignees: LG ELECTRONICS INC., KOREA ELECTRICAL ENGINEERING & SCIENCE RESEARCH INSTITUTE
    Inventors: Yong-Soon Park, Seung-Ki Sul, Chun-Ho Lim, Seong-Hun Lee, Ki-Sung Lee
  • Patent number: 9136790
    Abstract: An inverter control apparatus and a control method thereof are provided. The inverter control apparatus and a control method thereof stably operate a three-phase motor using a capacitor having a small capacitance for a DC link. The inverter control apparatus includes a current sensor to sense an output current of the inverter, a voltage sensor to sense a DC-link voltage of the inverter, and a controller to generate an average of a periodically varying rotor based q-axis current boundary value based on the output current and the DC-link voltage to generate a current reference on the basis of the average of the rotor based q-axis current boundary value, and to drive a three-phase motor based on the current reference. Stabilized variable speed control of a motor by using a small-capacitance capacitor for a DC link of an inverter is performed and reliability of an inverter circuit improved.
    Type: Grant
    Filed: November 23, 2012
    Date of Patent: September 15, 2015
    Assignees: SAMSUNG ELECTRONICS CO., LTD., SNU R&DB FOUNDATION
    Inventors: Young Jae Park, Han Sol Seo, Bodrov Alexey, Seung Ki Sul, Hyun-Sam Jung, Seung-Jun Chee
  • Patent number: 9112445
    Abstract: A winding synchronous machine having a moving object including an inverter circuit comprises: a moving-object inverter circuit connected to the moving object of the winding synchronous machine; and a moving-object circuit control device connected to the moving-object inverter circuit so as to control the moving-object inverter circuit. The moving-object circuit control device may comprise: a stator inverter voltage estimator estimating a high-frequency voltage of a stator inverter circuit; a field current reference generator generating a field current reference of the moving object; and an energy storage device voltage controller generating a current reference tracking a DC-link energy storage device voltage of the moving object. Problems associated with using a rare-earth permanent magnet can be thereby overcome, and a winding synchronous machine including an excitation circuit in which ripples almost never occur can be implemented without using an extra power source.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: August 18, 2015
    Assignee: SNU R&DB Foundation
    Inventors: Seung-Ki Sul, Jung-Ik Ha, Eunsoo Jung