Patents by Inventor Seok Hee Han

Seok Hee Han 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: 20240079870
    Abstract: Techniques to reduce discontinuities in power, for example, by controlling an electrical power output of an active front end unit during a transition between a first operating mode and a second operating mode. In some examples, to reduce discontinuities, a control unit of the active front end unit can seed the integrator of proportional-integral (PI) controllers that are brought online during the operating mode change with a value that represents the proper state of the current system, such as the measured or calculated value of the component the PI controller is controlling). In other examples, to reduce discontinuities, a control unit of the active front end unit can control reference frame alignment during a transition between a first operating mode and a second operating mode.
    Type: Application
    Filed: September 1, 2022
    Publication date: March 7, 2024
    Applicant: Caterpillar Inc.
    Inventors: Seok-hee Han, Jesse R. Gerdes, Jackson Wai
  • Publication number: 20240079876
    Abstract: Techniques to limit electrical power when forming an electrical grid using an active front end unit having an inverter that is coupled to a capacitor (and inductor) that is coupled to an electrical grid. For example, to limit power, the integration of a commanded frequency of the system can be limited to be within a specified phase delta of a measured phase angle of an electrical grid voltage vector. The calculation from power limit to phase delta can be done when the phase of the electrical grid voltage vector has been determined to be accurate and is calculated based on the measured capacitor voltage, grid voltage, and the estimated voltage drop across the output components of the system.
    Type: Application
    Filed: September 1, 2022
    Publication date: March 7, 2024
    Applicant: Caterpillar Inc.
    Inventors: Seok-hee Han, Jesse R. Gerdes, Jackson Wai
  • Patent number: 11850805
    Abstract: A method for manufacturing a PDMS device in accordance with an exemplary embodiment of the present invention surface treats the entire surface of a pattern with a thiol group (—SH), so that a hydrogel may be connected to the surface of the pattern by a covalent bond under ultraviolet rays. Therefore, a PDMS device manufactured by the above method has an advantage in that the shape thereof may be stably maintained without the swelling or desorption of a hydrogel even when an electrolyte is filled in a pattern.
    Type: Grant
    Filed: July 1, 2021
    Date of Patent: December 26, 2023
    Assignee: SEOUL NATIONAL UNIVERSITY R & DB FOUNDATION
    Inventors: Taek Dong Chung, Young-Chang Joo, Jeong-Yun Sun, Seok Hee Han, Sung Il Kim, Hae-Ryung Lee, Seung-Min Lim
  • Publication number: 20230396054
    Abstract: An apparatus can include an inverter to provide an output N-phase alternating-current to an external component. When N equals two, a phase of the N phases can include an upper gate and a lower gate. The apparatus can also include a current detector configured to detect a phase current magnitude of the output alternating current. The apparatus can also include a controller coupled to the current detector and to the inverter. The controller can generate a gate command for controlling a gate of the inverter. The controller can also determine a value for a current threshold less than a shutoff current threshold for the external component. The controller can provide a protection command to turn off the upper gate of a corresponding phase of the inverter responsive to detecting that the phase current magnitude is greater than the current threshold.
    Type: Application
    Filed: June 1, 2022
    Publication date: December 7, 2023
    Applicant: Caterpillar Inc.
    Inventors: Jesse R. Gerdes, Jackson Wai, Seok-hee Han
  • Patent number: 11474069
    Abstract: Disclosed is an open-junction ionic transistor which includes: a substrate; a p type gel which is formed as a polyelectrolyte gel on the substrate; an n type gel which is formed as the polyelectrolyte gel on the substrate and having one side contacting one side of the p type gel; a first reservoir contacting the other side of the p type gel; a second reservoir contacting the other side of the n type gel; and an encapsulation layer covering the p type gel, the n type gel, the first reservoir, and the second reservoir, in which on the encapsulation layer, an injection unit for injecting an ion input is formed at a location corresponding to an interface contacting the p type gel and the n type gel and when reverse bias voltage is applied between the p type gel and the n type gel, the ion input injected through the injection unit is amplified and ionic current peak is generated.
    Type: Grant
    Filed: May 29, 2020
    Date of Patent: October 18, 2022
    Assignee: SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION
    Inventors: Jeong-Yun Sun, Young-Chang Joo, Taek Dong Chung, Hae-Ryung Lee, Seung-Min Lim, Seok Hee Han, Hyunjae Yoo
  • Publication number: 20220063211
    Abstract: A method for manufacturing a PDMS device in accordance with an exemplary embodiment of the present invention surface treats the entire surface of a pattern with a thiol group (—SH), so that a hydrogel may be connected to the surface of the pattern by a covalent bond under ultraviolet rays. Therefore, a PDMS device manufactured by the above method has an advantage in that the shape thereof may be stably maintained without the swelling or desorption of a hydrogel even when an electrolyte is filled in a pattern.
    Type: Application
    Filed: July 1, 2021
    Publication date: March 3, 2022
    Inventors: Taek Dong CHUNG, Young-Chang JOO, Jeong-Yun SUN, Seok Hee HAN, Sung Il KIM, Hae-Ryung LEE, Seung-Min LIM
  • Publication number: 20200378918
    Abstract: Disclosed is an open-junction ionic transistor which includes: a substrate; a p type gel which is formed as a polyelectrolyte gel on the substrate; an n type gel which is formed as the polyelectrolyte gel on the substrate and having one side contacting one side of the p type gel; a first reservoir contacting the other side of the p type gel; a second reservoir contacting the other side of the n type gel; and an encapsulation layer covering the p type gel, the n type gel, the first reservoir, and the second reservoir, in which on the encapsulation layer, an injection unit for injecting an ion input is formed at a location corresponding to an interface contacting the p type gel and the n type gel and when reverse bias voltage is applied between the p type gel and the n type gel, the ion input injected through the injection unit is amplified and ionic current peak is generated.
    Type: Application
    Filed: May 29, 2020
    Publication date: December 3, 2020
    Inventors: Jeong-Yun SUN, Young-Chang Joo, Taek Dong Chung, Hae-Ryung LEE, Seung-Min LIM, Seok Hee HAN, Hyunjae YOO
  • Patent number: 10193475
    Abstract: A method for determining rotor position of a switched reluctance (SR) machine having a rotor and a stator is provided. The method may include injecting a test pulse into one or more idle phases of the SR machine, determining a decoupled flux value based at least partially on a total flux value corresponding to the test pulse and a mutual flux value, and determining the rotor position based at least partially on the decoupled flux value.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: January 29, 2019
    Assignee: Caterpillar Inc.
    Inventors: Seok-hee Han, Carlos Nino Baron, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Jesse Gerdes, James Michael Thorne
  • Patent number: 10097117
    Abstract: A control system is provided for an electric machine having a rotor and a stator. The control system has a converter circuit in electrical communication with the stator and a controller in electrical communication with the converter circuit. The controller is configured to receive a first signal indicating a torque applied to or output by the rotor and receive a second signal indicating a rotational speed of the rotor. The controller is also configured to determine at least one characteristic of a pulse signal based on at least one of the first or second signal. The controller is also configured to inject the pulse signal into one or more phases of the stator via the converter circuit according to the determined at least one characteristic. The controller is also configured to determine a position of the rotor based on the injected pulse signal.
    Type: Grant
    Filed: December 15, 2016
    Date of Patent: October 9, 2018
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, Seok-Hee Han, Jackson Wai, Sangameshwar Sonth, Jesse Gerdes, James M. Thorne
  • Patent number: 10079566
    Abstract: A system and method for estimating a position and a speed of a rotor of a Switched Reluctance (SR) machine is provided. The SR machine comprises the rotor, a stator and at least one winding. The method includes generating a diagnostic pulse having a trapezoidal shape. The method further includes injecting a diagnostic pulse into the at least one winding of the SR machine. The method further includes measuring an actual stator current flowing through the at least one winding of the SR machine. The method further includes computing an estimated stator current flowing through the at least one winding using observer-based estimation technique. The estimated stator current is compared with the actual stator current to compute an error signal. At least one of the position and the speed of the rotor is estimated based on the error signal.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: September 18, 2018
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, Seok-Hee Han, Jackson Wai, James Michael Thorne, Jesse Gerdes, Sangameshwar Sonth
  • Publication number: 20180175754
    Abstract: A control system is provided for an electric machine having a rotor and a stator. The control system has a converter circuit in electrical communication with the stator and a controller in electrical communication with the converter circuit. The controller is configured to receive a first signal indicating a torque applied to or output by the rotor and receive a second signal indicating a rotational speed of the rotor. The controller is also configured to determine at least one characteristic of a pulse signal based on at least one of the first or second signal. The controller is also configured to inject the pulse signal into one or more phases of the stator via the converter circuit according to the determined at least one characteristic. The controller is also configured to determine a position of the rotor based on the injected pulse signal.
    Type: Application
    Filed: December 15, 2016
    Publication date: June 21, 2018
    Applicant: Caterpillar Inc.
    Inventors: Ahmed KHALIL, Seok-Hee HAN, Jackson WAI, Sangameshwar SONTH, Jesse GERDES, James M. THORNE
  • Patent number: 9899946
    Abstract: A control system for a switched reluctance (SR) machine having a rotor and a stator is provided. The control system may include a converter circuit in electrical communication between the stator and a common bus, and a controller configured to monitor a bus voltage of the converter circuit and a phase current of the SR machine. The controller may be configured to determine a phase voltage based on one or more of main pulses and any diagnostic pulses, determine an estimated flux based on the phase voltage and an associated mutual voltage, determine a rotor position based at least partially on the estimated flux, and control the SR machine based on the rotor position and a desired torque.
    Type: Grant
    Filed: February 10, 2016
    Date of Patent: February 20, 2018
    Assignee: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Sangameshwar Sonth, Jesse Gerdes, James Michael Thorne
  • Patent number: 9800192
    Abstract: A control system for a multi-phase switched reluctance (SR) machine, having at least two phases, is disclosed. The control system may include a converter circuit and a controller. The controller may include a phase voltage estimator module configured to determine a first phase voltage and a second phase voltage associated with a second phase second phase for the SR machine. The controller may further include a flux estimator module configured to determine first and second estimated fluxes, the first estimated flux associated with the first phase and based on the first phase voltage and an associated first mutual voltage and the second estimated flux the second estimated flux associated with the second phase and based on the second phase voltage and an associated second mutual voltage, and a position observer module configured to determine a rotor position based at least partially on the first estimated flux, the second mutual flux.
    Type: Grant
    Filed: April 7, 2016
    Date of Patent: October 24, 2017
    Assignee: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Jesse Gerdes, James Michael Thorne, Sangameshwar Sonth
  • Publication number: 20170294858
    Abstract: A control system for a multi-phase switched reluctance (SR) machine, having at least two phases, is disclosed. The control system may include a converter circuit and a controller. The controller may include a phase voltage estimator module configured to determine a first phase voltage and a second phase voltage associated with a second phase second phase for the SR machine. The controller may further include a flux estimator module configured to determine first and second estimated fluxes, the first estimated flux associated with the first phase and based on the first phase voltage and an associated first mutual voltage and the second estimated flux the second estimated flux associated with the second phase and based on the second phase voltage and an associated second mutual voltage, and a position observer module configured to determine a rotor position based at least partially on the first estimated flux, the second mutual flux.
    Type: Application
    Filed: April 7, 2016
    Publication date: October 12, 2017
    Applicant: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Jesse Gerdes, James Michael Thorne, Sangameshwar Sonth
  • Publication number: 20170229992
    Abstract: A control system for a switched reluctance (SR) machine having a rotor and a stator is provided. The control system may include a converter circuit in electrical communication between the stator and a common bus, and a controller configured to monitor a bus voltage of the converter circuit and a phase current of the SR machine. The controller may be configured to determine a phase voltage based on one or more of main pulses and any diagnostic pulses, determine an estimated flux based on the phase voltage and an associated mutual voltage, determine a rotor position based at least partially on the estimated flux, and control the SR machine based on the rotor position and a desired torque.
    Type: Application
    Filed: February 10, 2016
    Publication date: August 10, 2017
    Applicant: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Sangameshwar Sonth, Jesse Gerdes, James Michael Thorne
  • Publication number: 20170126156
    Abstract: A method for determining rotor position of a switched reluctance (SR) machine having a rotor and a stator is provided. The method may include injecting a test pulse into one or more idle phases of the SR machine, determining a decoupled flux value based at least partially on a total flux value corresponding to the test pulse and a mutual flux value, and determining the rotor position based at least partially on the decoupled flux value.
    Type: Application
    Filed: May 18, 2015
    Publication date: May 4, 2017
    Applicant: Caterpillar Inc.
    Inventors: Seok-hee Han, Carlos Nino Baron, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Jesse Gerdes, James Michael Thorne
  • Publication number: 20150381087
    Abstract: A method for determining rotor position of a switched reluctance (SR) machine having a rotor and a stator is provided. The method may include injecting a test pulse into one or more idle phases of the SR machine, determining a decoupled flux value based at least partially on a total flux value corresponding to the test pulse and a mutual flux value, and determining the rotor position based at least partially on the decoupled flux value.
    Type: Application
    Filed: June 25, 2014
    Publication date: December 31, 2015
    Inventors: Seok-hee Han, Carlos Nino Baron, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Jesse Gerdes, James Michael Thorne
  • Patent number: 8779702
    Abstract: A control system for use with a motor is disclosed. The control system may have a controller that is configured to receive a torque command for the motor and receive a rotor angular velocity signal indicative of an angular velocity of a rotor of the motor. The controller may also be configured to generate a field weakening command by adding a field weakening adjustment signal to the rotor angular velocity signal, and generate a torque voltage command and a flux voltage command based on the torque command and the field weakening command. Further, the controller may be configured to convert the torque voltage command and the flux voltage command into phase voltage commands and output the phase voltage commands.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: July 15, 2014
    Assignee: Caterpillar Inc.
    Inventors: Baojun Si, Seok-Hee Han, Osama Mohammad Alkhouli
  • Publication number: 20120306423
    Abstract: A control system for use with a motor is disclosed. The control system may have a controller that is configured to receive a torque command for the motor and receive a rotor angular velocity signal indicative of an angular velocity of a rotor of the motor. The controller may also be configured to generate a field weakening command by adding a field weakening adjustment signal to the rotor angular velocity signal, and generate a torque voltage command and a flux voltage command based on the torque command and the field weakening command. Further, the controller may be configured to convert the torque voltage command and the flux voltage command into phase voltage commands and output the phase voltage commands.
    Type: Application
    Filed: June 6, 2011
    Publication date: December 6, 2012
    Inventors: Baojun SI, Seok-Hee Han, Osama Mohammad Alkhouli
  • Patent number: 8188114
    Abstract: The present invention provides novel pyrrolo[2,3-c]pyridine derivatives or pharmaceutically acceptable salts thereof, processes for the preparation thereof, and compositions comprising the same. The pyrrolo[2,3-c]pyridine derivatives or pharmaceutically acceptable salts thereof of the present invention have excellent proton pump inhibition effects and possess the ability to attain a reversible proton pump inhibitory effect.
    Type: Grant
    Filed: November 6, 2009
    Date of Patent: May 29, 2012
    Assignee: Yuhan Corporation
    Inventors: Jae-Gyu Kim, Byung-Nak Ahn, Hyouk-Woo Lee, Suk-Won Yoon, Young-Ae Yoon, Dong-Hoon Kim, Chan-Sun Park, Seok-Hee Han, Myung-Hun Cha, Heui II Kang, Sun-Young Jang