Now showing items 8-27 of 47

    • A diffusion-viscous analysis and experimental verification of defect formation in sintered silver bond-line 

      Xiao, Kewei; Ngo, Khai D. T.; Lu, Guo-Quan (Cambridge University Press, 2014-04-01)
      The low-temperature joining technique (LTJT) by silver sintering is being implemented by major manufacturers of power electronic devices and modules for bonding power semiconductor chips. A common die-attach material used ...
    • Anti-islanding detection for three-phase distributed generation 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Dong, Dong; Boroyevich, Dushan; Mattavelli, Paolo (United States Patent and Trademark Office, 2017-04-25)
      Wobbling the operating frequency of a phase-locked loop (PLL), preferably by adding a periodic variation is feedback gain or delay in reference signal phase allows the avoidance of any non-detection zone that might occur ...
    • Avoiding internal switching loss in soft switching cascode structure device 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Lee, Fred C.; Huang, Xiucheng; Du, Weijing (United States Patent and Trademark Office, 2017-08-15)
      In a cascode switching device, avalanche breakdown of a control transistor and loss of soft switching or zero voltage switching in a high voltage normally-on depletion mode transistor having a negative switching threshold ...
    • Center Program Snapshot (April 2009) 

      Virginia Tech. Center for Power Electronics Systems (Virginia Tech. Center for Power Electronics Systems, 2009-04)
      With the widespread use of power electronics technology, the United States would be able to cut electrical energy consumption by 33 percent. The energy savings, by today’s measure, is equivalent to the total output of 840 ...
    • Colossal tunability in high frequency magnetoelectric voltage tunable inductors 

      Yan, Yongke; Geng, Liwei D.; Tan, Yaohua; Ma, Jianhua; Zhang, Lujie; Sanghadasa, Mohan; Ngo, Khai; Ghosh, Avik W.; Wang, Yu U.; Priya, Shashank (2018-11-27)
      The electrical modulation of magnetization through the magnetoelectric effect provides a great opportunity for developing a new generation of tunable electrical components. Magnetoelectric voltage tunable inductors (VTIs) ...
    • Correlation between tunability and anisotropy in magnetoelectric voltage tunable inductor (VTI) 

      Yan, Yongke; Geng, Liwei D.; Zhang, Lujie; Gao, Xiangyu; Gollapudi, Sreenivasulu; Song, Hyun-Cheol; Dong, Shuxiang; Sanghadasa, Mohan; Khai Ngo; Wang, Yu U.; Priya, Shashank (Springer Nature, 2017-11-22)
      Electric field modulation of magnetic properties via magnetoelectric coupling in composite materials is of fundamental and technological importance for realizing tunable energy efficient electronics. Here we provide ...
    • CPES : 10-Year Progress Report 

      Virginia Tech. Center for Power Electronics Systems; Uncork-It, Inc. (Virginia Tech. Center for Power Electronics Systems, 2010-04)
      A major strength of CPES is its ability to use a wealth of existing resources and industrial collaboration. Virginia Tech, the University of Wisconsin-Madison (UW), and Rensselaer Polytechnic Institute (RPI) are the nation’s ...
    • CPES : Mini-Consortium Brochure 

      Virginia Tech. Center for Power Electronics Systems (Virginia Tech. Center for Power Electronics Systems, 2011-04)
      The CPES mini-consortium model provides a unique mechanism for all participants in power electronics – including industry competitors – to pool efforts to address their common challenges and develop pre-competitive Advances. ...
    • CPES Annual Report 2019 

      Unknown author (Virginia Tech. Center for Power Electronics Systems, 2019)
      In its effort to develop power processing systems to take electricity to the next step, CPES has cultivated research expertise encompassing five technology areas: (1) power conversion technologies and architectures; (2) ...
    • CPES Annual Report 2020 

      Unknown author (Virginia Tech, 2020)
      This CPES Annual Report provides a quick insight to the Center's research efforts in 2020.
    • CPES Annual Report 2021 

      Unknown author (Virginia Tech, 2021)
      This book is a comprehensive record of the center’s accomplishments during the year 2020.
    • CPES Center Brochure (April 2011) 

      Virginia Tech. Center for Power Electronics Systems; Uncork-It, Inc. (Virginia Tech. Center for Power Electronics Systems, 2011-04)
      The Center for Power Electronics Systems is a $4 million/year research center dedicated to improving electrical power processing and dis­tribution that impact systems of all sizes –from battery-operated electronics to ...
    • Energy storage for power factor correction in battery charger for electric-powered vehicles 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Wang, Hui; Ngo, Khai Doan (United States Patent and Trademark Office, 2018-03-13)
      Switches of a switching circuit used to control operation of an electric motor such as in an electrically powered vehicle connect respective windings of the electric motor as a single phase inductor during battery charging. ...
    • External ramp autotuning for current mode control of switching converter 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Liu, Pei-Hsin; Lee, Fred C.; Mattavelli, Paolo; Yan, Yingyi (United States Patent and Trademark Office, 2017-06-13)
      Peak current, valley current or average current mode controlled power converters in either digital or analog implementations obtain a stabilized feedback loop and allow high system bandwidth design by use of an external ...
    • High frequency integrated point-of-load power converter with embedded inductor substrate 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Lee, Fred C.; Su, Yipeng; Zhang, Wenli (United States Patent and Trademark Office, 2017-02-07)
      A low profile power converter structure is provide wherein volume is reduced and power density is increased to approach 1 KW/in3 by at least one of forming an inductor as a body of magnetic material embedded in a substrate ...
    • Hybrid interleaving structure with adaptive phase locked loop for variable frequency controlled switching converter 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Liu, Pei-Hsin; Lee, Fred C. (United States Patent and Trademark Office, 2018-07-03)
      In a multi-phase power converter using a phase-locked loop (PLL) arrangement for interleaving of pulse frequency modulated (PFM) pulses of the respective phases, improved transient response, improved stability of high ...
    • Iaverage current mode (ACM) control for switching power converters 

      Electrical and Computer Engineering; Center for Power Electronics Systems (CPES); Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Mattavelli, Paolo; Yan, Yingyi (United States Patent and Trademark Office, 2016-05-17)
      Providing a fast current sensor direct feedback path to a modulator for controlling switching of a switched power converter in addition to an integrating feedback path which monitors average current for control of a modulator ...
    • 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. ...