Patents by Inventor Hsien-Kai WANG

Hsien-Kai WANG 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: 20240178740
    Abstract: A power converter with reduced power consumption receives an input voltage and provides an output voltage to supply power to a load. The power converter includes a power factor correction circuit, a driver circuit, and a controller. The power factor correction circuit includes at least one inductor and an output capacitor. When the controller determines that an effective value of an input current is correspondingly lower than a current lower limit, a specific time period starts based on the output voltage reaching a voltage lower limit, and the specific time period ends based on the output voltage reaching a voltage upper limit. In the specific time period, the controller enables the driver circuit based on the input current being correspondingly greater than a predetermined threshold so as to continuously transfer the energy stored in the at least one inductor to the output capacitor.
    Type: Application
    Filed: April 13, 2023
    Publication date: May 30, 2024
    Inventors: Shang-Kay YANG, Hsien-Kai WANG, Yen-Wei LIN
  • Patent number: 11990836
    Abstract: A power supply system with dynamic current sharing includes a current-sharing bus and a plurality of power supply units connected to each other through the current-sharing bus. The current-sharing bus provides a first current signal. Each power supply unit includes a local current bus for providing a second current signal. The active current-sharing unit compares the first current signal with the second current signal to generate a compensation voltage. The current-averaging unit compares a difference value between an average value of the first current signal and an average value of the second current signal to generate an average voltage. The droop current unit receives the second current signal to generate a droop compensation voltage. The integration calculation unit makes output currents of the power supply units be approximately equal according to the compensation voltage, the average voltage, and the droop compensation voltage.
    Type: Grant
    Filed: April 5, 2022
    Date of Patent: May 21, 2024
    Assignee: DELTA ELECTRONICS, INC.
    Inventors: Chi-Hung Lin, Guo-Hua Wang, Yu-Jie Lin, Hsien-Kai Wang
  • Publication number: 20230231485
    Abstract: A bridge converter converts an input voltage into an output voltage, and includes a switching circuit, a transformer, a rectifying circuit, and a control module. The switching circuit includes a first switch and a second switch. The control module sets a first time period and a second time period. The control module provides a first control signal and a second control signal to control the switching circuit based on the output voltage. The control module fixes an operation frequency of the first control signal and the second control signal at the maximum frequency based on that the control module is set in a standby mode, and provides the first control signal and the second control signal in the first time period, and shields the first control signal and the second control signal in the second time period.
    Type: Application
    Filed: June 2, 2022
    Publication date: July 20, 2023
    Inventors: Shang-Kay YANG, Hsien-Kai WANG, Yen-Wei LIN
  • Patent number: 11677326
    Abstract: An LLC resonant converter includes a transformer and a primary-side circuit coupled to the transformer. The primary-side circuit includes a first bridge arm, a second bridge arm, and a control unit. The first bridge arm includes a first switch and a second switch, and the second bridge arm includes a third switch and a fourth switch. The control unit provides a first control signal to control the first switch and provides a fourth control signal to control the fourth switch. The control unit adjusts a switching frequency of the first control signal and the fourth control signal according to an output voltage. When the switching frequency increases to a frequency threshold value, the switching frequency is controlled to be fixed at the frequency threshold, and the first control signal and the fourth control signal are controlled to have a variable phase difference.
    Type: Grant
    Filed: May 27, 2021
    Date of Patent: June 13, 2023
    Assignee: DELTA ELECTRONICS, INC.
    Inventors: Shang-Kay Yang, Hsien-Kai Wang, Yen-Wei Lin
  • Patent number: 11658584
    Abstract: An LLC resonance converter includes a switching circuit, a resonance tank, a transformer, a synchronous rectification unit, and a control unit. The switching circuit includes a first switch controlled by a first control signal and a second switch controlled by a second control signal. The synchronous rectification unit includes a first synchronous rectification switch controlled by a first rectification control signal and a second synchronous rectification switch controlled by a second rectification control signal. The first control signal, the first rectification control signal, the second control signal, and the second rectification control signal include an operation frequency and a phase shift amount. When the operating frequency is lower to a specific value or the phase shift amount is higher to a specific value, the control unit fixes one of them to extend a hold-up time of the LLC resonance converter.
    Type: Grant
    Filed: November 24, 2021
    Date of Patent: May 23, 2023
    Assignee: DELTA ELECTRONICS, INC.
    Inventors: Shang-Kay Yang, Hsien-Kai Wang, Yen-Wei Lin
  • Publication number: 20230147990
    Abstract: A power supply system with dynamic current sharing includes a current-sharing bus and a plurality of power supply units connected to each other through the current-sharing bus. The current-sharing bus provides a first current signal. Each power supply unit includes a local current bus for providing a second current signal. The active current-sharing unit compares the first current signal with the second current signal to generate a compensation voltage. The current-averaging unit compares a difference value between an average value of the first current signal and an average value of the second current signal to generate an average voltage. The droop current unit receives the second current signal to generate a droop compensation voltage. The integration calculation unit makes output currents of the power supply units be approximately equal according to the compensation voltage, the average voltage, and the droop compensation voltage.
    Type: Application
    Filed: April 5, 2022
    Publication date: May 11, 2023
    Inventors: Chi-Hung LIN, Guo-Hua WANG, Yu-Jie LIN, Hsien-Kai WANG
  • Publication number: 20220416677
    Abstract: An LLC resonance converter includes a switching circuit, a resonance tank, a transformer, a synchronous rectification unit, and a control unit. The switching circuit includes a first switch controlled by a first control signal and a second switch controlled by a second control signal. The synchronous rectification unit includes a first synchronous rectification switch controlled by a first rectification control signal and a second synchronous rectification switch controlled by a second rectification control signal. The first control signal, the first rectification control signal, the second control signal, and the second rectification control signal include an operation frequency and a phase shift amount. When the operating frequency is lower to a specific value or the phase shift amount is higher to a specific value, the control unit fixes one of them to extend a hold-up time of the LLC resonance converter.
    Type: Application
    Filed: November 24, 2021
    Publication date: December 29, 2022
    Inventors: Shang-Kay YANG, Hsien-Kai WANG, Yen-Wei LIN
  • Patent number: 11509213
    Abstract: An LLC resonant converter includes a square wave generator having a first switch and a second switch, a resonant tank, a transformer, a synchronous rectifying (SR) unit having a first SR switch and a second SR switch, and a control unit. The control unit provides a first control signal controls the first switch, a second control signal controls the second switch, a first rectifying control signal controls the first SR switch, a second rectifying control signal controls the second SR switch. When a frequency control command is lower than a phase-shift frequency, the first control signal and the first rectifying control signal are frequency-variable and phase-shifted, and the second control signal and the second rectifying control signal are frequency-variable and phase-shifted.
    Type: Grant
    Filed: July 8, 2021
    Date of Patent: November 22, 2022
    Assignee: Delta Electronics, Inc.
    Inventors: Shang-Kay Yang, Hsien-Kai Wang, Yen-Wei Lin
  • Publication number: 20220103082
    Abstract: An LLC resonant converter includes a square wave generator having a first switch and a second switch, a resonant tank, a transformer, a synchronous rectifying (SR) unit having a first SR switch and a second SR switch, and a control unit. The control unit provides a first control signal controls the first switch, a second control signal controls the second switch, a first rectifying control signal controls the first SR switch, a second rectifying control signal controls the second SR switch. When a frequency control command is lower than a phase-shift frequency, the first control signal and the first rectifying control signal are frequency-variable and phase-shifted, and the second control signal and the second rectifying control signal are frequency-variable and phase-shifted.
    Type: Application
    Filed: July 8, 2021
    Publication date: March 31, 2022
    Inventors: Shang-Kay YANG, Hsien-Kai WANG, Yen-Wei LIN
  • Publication number: 20220103080
    Abstract: An LLC resonant converter includes a transformer and a primary-side circuit coupled to the transformer. The primary-side circuit includes a first bridge arm, a second bridge arm, and a control unit. The first bridge arm includes a first switch and a second switch, and the second bridge arm includes a third switch and a fourth switch. The control unit provides a first control signal to control the first switch and provides a fourth control signal to control the fourth switch. The control unit adjusts a switching frequency of the first control signal and the fourth control signal according to an output voltage. When the switching frequency increases to a frequency threshold value, the switching frequency is controlled to be fixed at the frequency threshold, and the first control signal and the fourth control signal are controlled to have a variable phase difference.
    Type: Application
    Filed: May 27, 2021
    Publication date: March 31, 2022
    Inventors: Shang-Kay YANG, Hsien-Kai WANG, Yen-Wei LIN