Patents by Inventor Dakai WANG

Dakai 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: 20260162882
    Abstract: An integrated magnetic component and a manufacturing method thereof for a multi-module DC-DC converter are provided. The integrated magnetic component includes N primary windings, N secondary windings and N magnetic cores, and N is an integer greater than one. The N magnetic cores are arranged sequentially, and each magnetic core includes a plate, first and second common core legs, an inductor core leg and a transformer core leg. The first common core leg and the second common core leg are disposed at a first side and a second side of the plate respectively. The inductor core leg is configured to be wound with a corresponding primary or secondary winding, and the transformer core leg is configured to be wound with the corresponding primary and secondary windings interleaved with each other.
    Type: Application
    Filed: November 26, 2025
    Publication date: June 11, 2026
    Inventors: Feng Jin, Dakai Wang, Misha Kumar, Peter Mantovanelli Barbosa
  • Publication number: 20260149367
    Abstract: An integrated magnetic component is disclosed and includes a plurality of PCBs, a transformer and a plurality of inductors. The transformer includes a plurality of primary windings, a plurality of secondary windings, and two pieces of transformer cores. The primary windings and the secondary windings are disposed on the PCBs and wound around the two pieces of transformer cores. The inductors are disposed on the PCBs and connected to the transformer. The primary windings and the secondary windings of the transformer are disposed correspondingly in pairs on one of the PCBs, and the inductors are disposed adjacent to the transformer.
    Type: Application
    Filed: November 18, 2025
    Publication date: May 28, 2026
    Inventors: Dakai Wang, Feng Jin, Yi-Sheng Chang, Meng-Chi Tsai, Misha Kumar, Peter Mantovanelli Barbosa
  • Patent number: 12597786
    Abstract: Various examples are provided for high voltage isolation. The isolation can be provided for discrete non-isolated devices using an electrically isolating substrate that is thermally conductive. In one example, a module includes a plurality of switching devices connected in series; one or more rubber buffer disposed between switching device pairs of the plurality of switching devices; and thermal interfaces disposed between switching devices of the switching device pairs and cooling surfaces of the module, the thermal interfaces electrically isolating the switching devices from the cooling surface. In another example, an extreme fast charger (EFC) station includes an active front end (AFE) module that includes at least one module, where the module is a half-bridge power module. The EFC station can include a dual-active-bridge (DAB) high voltage (HV) module that includes at least one module, where the module is a half-bridge power module.
    Type: Grant
    Filed: May 31, 2022
    Date of Patent: April 7, 2026
    Assignee: NORTH CAROLINA STATE UNIVERSITY
    Inventors: Wensong Yu, Dakai Wang, Srdjan Miodrag Lukic
  • Publication number: 20260066804
    Abstract: A DC-DC power supply and a transformer assembly are provided. The DC-DC power supply includes primary and secondary circuits and M transformer sets electrically connected in parallel between the primary and secondary circuits. Each transformer set includes N transformers, where M and N are positive integers. Each transformer includes first and second primary windings and first and second secondary windings. A connection node of the first and second secondary windings is electrically connected to an output capacitor of the secondary circuit, and each secondary winding is electrically connected to a corresponding secondary switch of the secondary circuit. The first and second primary windings in each transformer set are electrically connected in series. All transformers are arranged along a first direction, and each transformer includes columns arranged along the first direction with each extending along a second direction perpendicular to the first direction.
    Type: Application
    Filed: August 26, 2025
    Publication date: March 5, 2026
    Inventors: Ripun Phukan, Feng Jin, Dakai Wang, Peter Mantovanelli Barbosa
  • Publication number: 20260058549
    Abstract: A resonant converter and a control method thereof are provided. The resonant converter includes primary and secondary circuits and a transformer. The control method includes: in first control mode, controlling primary switches of the primary circuit and secondary switches of the secondary circuit with a variable switching frequency; in second control mode, controlling a phase shift between the primary switches and the secondary switches; when an input voltage is within a preset range, controlling the resonant converter with the first control mode; when the input voltage changes from within the preset range to outside the preset range, transiting from the first control mode to the second control mode to maintain an output voltage within a predetermined range; and when the input voltage changes from outside the preset range to within the preset range, transiting from the second control mode to the first control mode.
    Type: Application
    Filed: August 20, 2025
    Publication date: February 26, 2026
    Inventors: Dakai Wang, Te-Chih Peng, Misha Kumar, Peter Mantovanelli Barbosa
  • Publication number: 20250364889
    Abstract: A modular stacked magnetic component is provided. The modular stacked magnetic component is for a DC-DC converter with N phases, and N is an odd number greater than 1. In the N phases, an nth phase is 360/N degrees leading an (n+1)th phase, n is a positive integer less than N, and an Nth phase is 360/N degrees leading a first phase. The modular stacked magnetic component includes N magnetic cores, a magnetic cover, and N windings. The N magnetic cores are stacked vertically in sequence. The magnetic cover is stacked on the top of the N magnetic cores. The N windings are connected to the N phases of the DC-DC converter respectively, and each winding is wound on winding columns of a corresponding magnetic core to form an integrated transformer and inductor. Any two adjacent windings have opposite current directions.
    Type: Application
    Filed: January 7, 2025
    Publication date: November 27, 2025
    Inventors: Dakai Wang, Meng-Chi Tsai, Te-Chih Peng, Misha Kumar, Peter Mantovanelli Barbosa
  • Publication number: 20250293615
    Abstract: The present disclosure provides a three-phase/single-phase compatible AC/DC converter and a control method. The three-phase/single-phase compatible AC/DC converter includes plural relays that, when selectively activated or deactivated, enables operation as a three-phase converter or a totem-pole PFC converter with a single-phase input, the totem-pole PFC converter having a parallel arrangement of a diode leg and a slow leg connected at their respective midpoints to neutral so as to operate in unity power factor or non-unity power factor. The method includes: operating plural fast legs at a first duty cycle for a period defined by a predefined range of an input voltage, and at least a second duty cycle outside of the period different than the first duty cycle for non-unity power factor cases; and increasing a switching frequency of the slow leg during the period while in non-unity power factor operation.
    Type: Application
    Filed: March 14, 2025
    Publication date: September 18, 2025
    Inventors: Nidhi Haryani, Dakai Wang, Marc Hagemeyer, Heiko Figge, Peter Mantovanelli Barbosa, Tomas Sadilek
  • Publication number: 20250293614
    Abstract: The present disclosure provides a totem-pole PFC converter and a control method thereof. The totem-pole PFC converter includes: a plurality of phase legs connected in parallel; a plurality of boost inductors, wherein each boost inductor is connected between the corresponding input terminal and the midpoint of the corresponding phase leg; a plurality of capacitors; a diode leg connected with the plurality of phase legs in parallel, wherein the midpoint of the diode leg is connected with the neutral terminal; an output filter connected with the diode leg in parallel; a T-type leg connected between the midpoint of the diode leg and the midpoint of the output filter and including two active switches connected in series; and a control system configured to turn the two active switches on around AC voltage zero crossings during non-unity power factor operation.
    Type: Application
    Filed: March 14, 2025
    Publication date: September 18, 2025
    Inventors: Nidhi Haryani, Dakai Wang, Marc Hagemeyer, Heiko Figge, Peter Mantovanelli Barbosa, Tomas Sadilek
  • Publication number: 20250253768
    Abstract: A three-phase power conversion circuit and a control method thereof are disclosed. The three-phase LLC power conversion circuit receives an input voltage, outputs an output voltage, and includes a three-phase transformer, an input switch group, an output switch group and a resonant circuit group. The control method includes steps of: S1: detecting each zero-crossing point of the input voltage, the output voltage and each output current in each phase; and S2: controlling the output switch group according to a ratio of the output voltage to the input voltage, wherein a switching state of at least one of the rectification switches is controlled to lead/lag the corresponding input switch, and/or adjusting each of the phases of the input switches to increase a duty cycle, wherein switching frequencies of the plurality of input switches are adjusted according to the output voltage, a reference voltage and a soft switching setting condition.
    Type: Application
    Filed: February 6, 2025
    Publication date: August 7, 2025
    Inventors: Dakai Wang, Meng-Chi Tsai, Te-Chih Peng, Peter Mantovanelli Barbosa
  • Publication number: 20250253778
    Abstract: A magnetic component for a three-phase power conversion circuit includes a magnetic core set, a three-phase transformer and a first three-phase resonant inductor. The three-phase transformer includes three transformers. The first three-phase resonant inductor includes three resonant inductors electrically connected to primary windings of the transformers.
    Type: Application
    Filed: February 6, 2025
    Publication date: August 7, 2025
    Inventors: Dakai Wang, Meng-Chi Tsai, Te-Chih Peng, Peter Mantovanelli Barbosa
  • Publication number: 20240305208
    Abstract: A power converter is provided that includes a power inverter, a rectifier circuit and an isolation transformer circuit. The power inverter is to convert a direct current (DC) input to an alternating current (AC) output, the power inverter including N bridge circuits connected in parallel, where N>1. The rectifier circuit is to convert the AC output to a DC output, the rectifier circuit including N+1 series diode pairs connected in parallel. The isolation transformer circuit is coupled to and between the power inverter and the rectifier circuit to transfer the AC output from the power inverter to the rectifier circuit, the isolation transformer circuit including N transformers. Respective ones of the N transformers are coupled to one of the N bridge circuits and two of the N+1 series diode pairs.
    Type: Application
    Filed: March 8, 2024
    Publication date: September 12, 2024
    Inventors: Wensong Yu, Dakai Wang, Xuning Zhang, Greg Mann, Steven Chenetz, Dennis Meyer, Ehab Tarmoom
  • Publication number: 20220385081
    Abstract: Various examples are provided for high voltage isolation. The isolation can be provided for discrete non-isolated devices using an electrically isolating substrate that is thermally conductive. In one example, a module includes a plurality of switching devices connected in series; one or more rubber buffer disposed between switching device pairs of the plurality of switching devices; and thermal interfaces disposed between switching devices of the switching device pairs and cooling surfaces of the module, the thermal interfaces electrically isolating the switching devices from the cooling surface. In another example, an extreme fast charger (EFC) station includes an active front end (AFE) module that includes at least one module, where the module is a half-bridge power module. The EFC station can include a dual-active-bridge (DAB) high voltage (HV) module that includes at least one module, where the module is a half-bridge power module.
    Type: Application
    Filed: May 31, 2022
    Publication date: December 1, 2022
    Inventors: Wensong Yu, Dakai Wang, Srdjan Miodrag Lukic
  • Patent number: 11472157
    Abstract: A bionic flexible actuator with a real-time feedback function and a preparation method thereof. The method includes: preparing stimuli-response layer and bionic flexible strain-sensor film layer, arranging bionic V-shaped groove array structure on bionic flexible strain-sensor film layer, and sticking bionic flexible strain-sensor film layer onto stimuli-response layer through adhesive layer; stimuli-response layer is prepared by adopting following steps: mixing multi-walled carbon nanotubes and polyvinylidene fluoride after being dissolved in a solvent respectively and obtaining a mixed solution; performing a film formation process to mixed solution and embedding a first electrode to obtain stimuli-response layer.
    Type: Grant
    Filed: October 30, 2019
    Date of Patent: October 18, 2022
    Assignee: JILIN UNIVERSITY
    Inventors: Zhiwu Han, Linpeng Liu, Junqiu Zhang, Dakai Wang, Tao Sun, Kejun Wang, Shichao Niu, Tao Hou
  • Patent number: 11456409
    Abstract: A micro-vibration sensor and preparation method thereof. The method includes a metal sheet is coated with first curing material, and first curing material is cured into first cured layer; piezoelectric thin film element is attached to edge of first cured layer; one side, attached with piezoelectric thin film element, of first cured layer is vertically placed into second curing material, and second curing material is cured into second cured layer; and metal sheet is removed to obtain micro-vibration sensor. Due to fact that piezoelectric thin film element is arranged at a crack tip, during micro-vibration, stress in stress field of crack tip is rapidly increased due to crack stress deformation, and stress signal is efficiently converted into electric signal; and micro-vibration sensor has characteristics of being low in detection limit and high in accuracy.
    Type: Grant
    Filed: October 31, 2019
    Date of Patent: September 27, 2022
    Assignee: JILIN UNIVERSITY
    Inventors: Zhiwu Han, Kejun Wang, Honglie Song, Junqiu Zhang, Daobing Chen, Linpeng Liu, Binjie Zhang, Tao Sun, Dakai Wang, Changchao Zhang
  • Publication number: 20210207939
    Abstract: A bionic flexible actuator with a real-time feedback function and a preparation method thereof. The method includes: preparing stimuli-response layer and bionic flexible strain-sensor film layer, arranging bionic V-shaped groove array structure on bionic flexible strain-sensor film layer, and sticking bionic flexible strain-sensor film layer onto stimuli-response layer through adhesive layer; stimuli-response layer is prepared by adopting following steps: mixing multi-walled carbon nanotubes and polyvinylidene fluoride after being dissolved in a solvent respectively and obtaining a mixed solution; performing a film formation process to mixed solution and embedding a first electrode to obtain stimuli-response layer.
    Type: Application
    Filed: October 30, 2019
    Publication date: July 8, 2021
    Applicant: JILIN UNIVERSITY
    Inventors: Zhiwu HAN, Linpeng LIU, Junqiu ZHANG, Dakai WANG, Tao SUN, Kejun WANG, Shichao NIU, Tao HOU
  • Publication number: 20210175411
    Abstract: A micro-vibration sensor and preparation method thereof. The method includes a metal sheet is coated with first curing material, and first curing material is cured into first cured layer; piezoelectric thin film element is attached to edge of first cured layer; one side, attached with piezoelectric thin film element, of first cured layer is vertically placed into second curing material, and second curing material is cured into second cured layer; and metal sheet is removed to obtain micro-vibration sensor. Due to fact that piezoelectric thin film element is arranged at a crack tip, during micro-vibration, stress in stress field of crack tip is rapidly increased due to crack stress deformation, and stress signal is efficiently converted into electric signal; and micro-vibration sensor has characteristics of being low in detection limit and high in accuracy.
    Type: Application
    Filed: October 31, 2019
    Publication date: June 10, 2021
    Applicant: JILIN UNIVERSITY
    Inventors: Zhiwu HAN, Kejun WANG, Honglie SONG, Junqiu ZHANG, Daobing CHEN, Linpeng LIU, Binjie ZHANG, Tao SUN, Dakai WANG, Changchao ZHANG