Now showing items 25-44 of 47

    • Low profile coupled inductor substrate with transient speed improvement 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Lee, Fred C.; Su, Yipeng; Hou, Dongbin (United States Patent and Trademark Office, 2018-10-23)
      A low profile inductor structure suitable for use in a high power density power converter has one or more windings formed by vias through a thin, generally planar body of magnetic material forming the inductor core and ...
    • Maximum power point tracking for solar panels 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Materials Science and Engineering (MSE); Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Wang, Feng; Wu, Xinke; Wang, Zijian (United States Patent and Trademark Office, 2017-06-20)
      Approximately one-half of the loss of delivered power from a solar panel having photovoltaic (PV) cells connected in series to form sub-panels due to shading is recovered at low hardware cost by connecting sub-panels in ...
    • Method and apparatus for current/power balancing 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Toyota Motor Engineering & Manufacturing North American, Inc.; Wang, Chi-Ming; Mao, Yincan; Miao, Zichen; Ngo, Khai D. (United States Patent and Trademark Office, 2018-03-20)
      Aspects of the disclosure provide a system having a power circuit. The power circuit includes a first switch circuit having at least a first transistor and a second switch circuit having at least a second transistor. ...
    • Method and apparatus for current/power balancing 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Toyota Motor Engineering & Manufacturing North American, Inc.; Wang, Chi-Ming; Mao, Yincan; Miao, Zichen; Ngo, Khai D. (United States Patent and Trademark Office, 2017-02-28)
      Aspects of the disclosure provide a power circuit that includes a first switch circuit in parallel with a second switch circuit. The first switch circuit and the second switch circuit are coupled to a first driving node, ...
    • Method and apparatus for driving a power device 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Toyota Motor Engineering & Manufacturing North American, Inc.; Wang, Chi-Ming; Shin, Jongwon; Ngo, Khai D. (United States Patent and Trademark Office, 2016-12-27)
      Aspects of the disclosure provide a circuit for driving a power switch. The circuit includes a first circuit configured to provide a charging current to charge a control terminal of the power switch, a second circuit ...
    • Method and apparatus to improve power device reliability 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Toyota Motor Engineering & Manufacturing North American, Inc.; Wang, Chi-Ming; Mao, Yincan; Miao, Zichen; Ngo, Khai D. (United States Patent and Trademark Office, 2017-05-23)
      Aspects of the disclosure provide a power device that includes an upper power module and a lower power module. The upper power module and the lower power module are coupled in series between two supply voltages, and are ...
    • Method for reducing or eliminating conducted common mode noise in a transformer 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Lee, Fred C.; Huang, Daocheng; Yang, Yuchen (United States Patent and Trademark Office, 2017-03-07)
      At least one shield member interposed between primary and secondary windings of a transformer and connected to the primary and/or secondary windings forms a distributed parasitic capacitance between the shield member and ...
    • Multi-step simplified optimal trajectory control (SOTC) based on only Vo and I load 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Lee, Fred C.; Fei, Chao; Feng, Weiyi (United States Patent and Trademark Office, 2018-09-11)
      A resonant power converter is disclosed with a driving circuit generating a switching signal connecting power to a resonant tank circuit, with a voltage monitoring circuit measuring a voltage output and a load current. A ...
    • Optimal trajectory control for LLC resonant converter for LED PWM dimming 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Polytechnic Institute and State University; Lee, Fred C.; Ji, Shu; Feng, Weiyi (United States Patent and Trademark Office, 2016-03-01)
      Pulse width modulation is provided for controlling a resonant power converter, particularly for dimming of light emitting diode arrays without loss of efficiency. Dynamic oscillation due to the beginning of a pulse width ...
    • Optimal trajectory control for LLC resonant converter for soft start-up 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Feng, Weiyi (United States Patent and Trademark Office, 2016-04-19)
      By setting switching instants of a switching circuit of a resonant power converter based on current in a resonant circuit reaching a current limit of a current limitation band, soft start-up of the power converter can be ...
    • Parallel devices having balanced switching current and power 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Toyota Motor Engineering & Manufacturing North American, Inc.; Wang, Chi-Ming; Mao, Yincan; Miao, Zichen; Ngo, Khai D. (United States Patent and Trademark Office, 2018-10-30)
      A power circuit includes a power source for providing electrical power and two driving transistors being disposed in parallel and receiving electrical power from the power source. Each of the two driving transistors includes ...
    • Power switch drivers with equalizers for paralleled switches 

      Virginia Tech Intellectual Properties, Inc.; Miao, Zichen; Ngo, Khai D.; Zhang, Lujie (United States Patent and Trademark Office, 2018-06-12)
      Capacitors connected between gate terminals of a plurality of parallel-connected power transistors are charged and discharged in each switching cycle to provide a plurality of power transistor control waveforms from a ...
    • Power-cell switching-cycle capacitor voltage control for modular multi-level converters 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Wang, Jun; Boroyevich, Dushan; Burgos, Rolando P.; Wen, Bo (United States Patent and Trademark Office, 2018-05-08)
      In a modular multi-level power converter, additional switching states are interleaved between main switching states that control output voltage or waveform. The additional switching states provide current from a DC-link ...
    • Semiconductor module arrangement 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; DiMarino, Christina; Boroyevich, Dushan; Burgos, Rolando P.; Johnson, Mark (United States Patent and Trademark Office, 2018-07-24)
      In a switching module structure that includes a low-impedance path to ground, such as a parasitic capacitance of an insulating substrate, a further insulating substrate presenting a parasitic capacitance placed in series ...
    • Structural Resemblance Between Droop Controllers and Phase-Locked Loops 

      Zhong, Qing-Chang; Boroyevich, Dushan (IEEE, 2016)
      It is well known that droop control is fundamental to the operation of power systems and now the parallel operation of inverters, while phase-locked loops (PLLs) are widely adopted in modern electrical engineering. In this ...
    • Superjunction Power Transistors With Interface Charges: A Case Study for GaN 

      Ma, Yunwei; Xiao, Ming; Zhang, Ruizhe; Wang, Han; Zhang, Yuhao (2019-12-13)
      Recent progress in p-GaN trench-filling epitaxy has shown promise for the demonstration of GaN superjunction (SJ) devices. However, the presence of n-type interface charges at the regrowth interfaces has been widely observed. ...
    • System and method for impedance measurement using chirp signal injection 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Huntington Ingalls Incorporated; Boroyevich, Dushan; Mattavelli, Paolo; Belkhayat, Mohamed; Shen, Zhiyu; Jaksic, Marko D.; Verhulst, Jacob (United States Patent and Trademark Office, 2017-04-11)
      A method for impedance measurement using chirp signal injection is provided. The method includes injecting at least one chirp signal into the three-phase AC system, and collecting at least one response to the at least one ...
    • System and method for impedance measurement using series and shunt injection 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Huntington Ingalls Incorporated; Boroyevich, Dushan; Mattavelli, Paolo; Belkhayat, Mohamed; Shen, Zhiyu; Jaksic, Marko D.; Verhulst, Jacob (United States Patent and Trademark Office, 2017-02-07)
      A method for impedance measurement in a three-phase AC system is provided. The method includes injecting a shunt perturbation signal into the three-phase AC system and collecting a response to the shunt perturbation signal, ...
    • Transient performance improvement for constant on-time power converters 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Liu, Pei-Hsin; Lee, Fred C.; Bari, Syed (United States Patent and Trademark Office, 2018-10-23)
      Response of a variable frequency switching constant on-time or adaptive on-time controlled power converter to a large step-up or step-down change in load is improved with a simple circuit that detects magnitude and polarity ...
    • Two-stage multichannel LED driver with CLL resonant circuit 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Lee, Fred C.; Chen, Xuebing; Huang, Daocheng (United States Patent and Trademark Office, 2017-01-10)
      In a two-stage power converter providing voltage regulation in a first stage, zero voltage switching (ZVS) is provided in switches in an unregulated, constant frequency second stage of a two-stage power converter by an ...