All Stories

  1. Emerging Trends in Industrial Electronics

    Article • IEEE Industrial Electronics Magazine, January 2021, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  2. Simultaneous Tuning of Rotor Shape and Phase Current of Switched Reluctance Motors for Eliminating Input Current and Torque Ripples With Reduced Copper Loss

    Article • IEEE Transactions on Industry Applications, November 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  3. Competition-Based Learning of Power Converter Design Emulating Product Development Activity

    Article • October 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  4. Analysis and Prediction of AC Resistance of Litz Wire with Rectangular Cross-Section

    Article • October 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  5. Multiple-Transmitter Achieving Load-Independent Transmitter Current and Compensation of Cross-Interference Among Transmitters for Wide Charging Area Wireless Power Transfer Systems

    Article • October 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  6. Optimization of Common Source Inductance and Gate-Drain Capacitance for Reducing Gate Voltage Fluctuation after Turn-off Transition

    Article • October 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  7. Homogenization of Current Distribution in Parallel Connection of Interleaved Winding Layers of High-Frequency Transformers by Optimizing Distance between Winding Layers

    Article • September 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  8. Current waveform for switched reluctance motors

    Article • IET Power Electronics, July 2020, the Institution of Engineering and Technology (the IET)

    Takayuki Kusumi, Prof. Kazuhiro Umetani

  9. Strategy of Topology Selection Based on Quasi-Duality Between Series–Series and Series–Parallel Topologies of Resonant Inductive Coupling Wireless Power Transfer Systems

    Article • IEEE Transactions on Power Electronics, July 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  10. Gate Drivers Techniques and Solutions for GaN HEMTs in High Frequency Applications

    Article • June 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani, Prof. Wilmar Martinez

  11. Secondary-Side Center-Tapped Transformer Structure with One-Turn Secondary Coils Integrating Rectifier for Reducing Copper Loss of Forward Converter

    Article • June 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani, Prof. Wilmar Martinez

  12. Effects of Secondary Leakage Inductance on the LLC Resonant Converter

    Article • IEEE Transactions on Power Electronics, January 2020, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  13. Axial Heating Coil Structure for Reducing Magnetic Levitation Force of All-Metal Type Induction Cookers

    Article • November 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  14. Verification of Device Model by Measuring Capacitance and Static Characteristics for Predicting Switching Waveform

    Article • November 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  15. Analytical Derivation of Phase Current Waveform Eliminating Torque Ripple and Input Current Ripple of Switched Reluctance Motors under Magnetically Saturated Operation

    Article • September 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  16. Automatic Active Compensation Method of Cross-Coupling in Multiple-receiver Resonant Inductive Coupling Wireless Power Transfer Systems

    Article • September 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  17. Experimental Verification of Impedance Matching Method for Repeater to Improve Spatial Freedom of 6.78 MHz Resonant Inductive Coupling Wireless Power Transfer Systems

    Article • September 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  18. Optimal Winding Layer Allocation for Minimizing Copper Loss of Secondary-Side Center-Tapped Forward Transformer with Parallel-Connected Secondary Windings

    Article • September 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  19. Resonant Frequency Tuning System for Repeater Resonator of Resonant Inductive Coupling Wireless Power Transfer

    Article • September 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  20. Receiving-Coil Structure Reducing Stray AC Resistance for Resonant Coupling Wireless Power Transfer

    Article • IET Power Electronics, June 2019, the Institution of Engineering and Technology (the IET)

    Prof. Kazuhiro Umetani

  21. Effects of Secondary Leakage Inductance on the LLC Resonant Converter—Part II: Frequency Control Bandwidth with respect to Load Variation

    Article • March 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  22. Effects of Secondary Leakage Inductance on the LLC Resonant Converter—Part I: Transformer Voltage Gain and Efficiency

    Article • March 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  23. Simple Fully Analytical Copper Loss Model of Litz Wire Made of Strands Twisted in Multiple Levels

    Article • March 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  24. Core Loss Modeling Based on Equivalent Circuit for Switched Reluctance Motors

    Article • February 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  25. Prevention of Oscillatory False Triggering of GaN-FETs by Balancing Gate-Drain Capacitance and Common-Source Inductance

    Article • IEEE Transactions on Industry Applications, January 2019, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  26. Magnetic Design and Experimental Evaluation of a Commercially Available Single Integrated Transformer in Three-Phase LLC Resonant Converter

    Article • IEEE Transactions on Industry Applications, November 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  27. Feasibility Study of Fractal-Fin Heat Sink for Improving Cooling Performance of Switching Power Converters

    Article • October 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  28. Improved Thin Heating Coil Structure of Copper Foil Feasible for Induction Cookers

    Article • October 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  29. Soft-Switching Control Circuit Based on Traveling and Reflected Waves for High-Frequency Resonant Inverter Applicable to Capacitive Load Impedance

    Article • October 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  30. Impedance Matching to Maximize Induced Current in Repeater of Resonant Inductive Coupling Wireless Power Transfer Systems

    Article • September 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  31. Rotor Configuration Which Reduces Copper Loss of Switched Reluctance Motors with Suppression of Torque Ripple and Input Current Ripple

    Article • September 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  32. A Current Sharing Method Utilizing Single Balancing Transformer for a Multiphase LLC Resonant Converter With Integrated Magnetics

    Article • IEEE Journal of Emerging and Selected Topics in Power Electronics, June 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  33. Review of Current Balance Mechanism in Multiphase LLC Resonant Converters

    Article • June 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  34. Theoretical Derivation of Phase Current Profile for Switched Reluctance Motors to Suppress Radial Force Ripple and Torque Ripple

    Article • June 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  35. Automatic Resonance Frequency Tuning Method for Repeater in Resonant Inductive Coupling Wireless Power Transfer Systems

    Article • May 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  36. High-frequency Self-Driven Synchronous Rectifier Controller for WPT Systems

    Article • May 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  37. Verification of the Reduction of the Copper Loss by the Thin Coil Structure for Induction Cookers

    Article • May 2018, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  38. Lagrangian dynamics model and practical implementation of an integrated transformer in multi-phase LLC resonant converter

    Article • IET Power Electronics, February 2018, the Institution of Engineering and Technology (the IET)

    Prof. Kazuhiro Umetani, jun imaoka, Mostafa Noah

  39. Winding orientation method to minimise the secondary leakage of a gapped transformer utilised in LLC resonant converter

    Article • Electronics Letters, February 2018, the Institution of Engineering and Technology (the IET)

    jun imaoka, Prof. Kazuhiro Umetani, Mostafa Noah

  40. Design Optimization Method for the Load Impedance to Maximize the Output Power in Dual Transmitting Resonator Wireless Power Transfer System

    Article • IEEJ Journal of Industry Applications, January 2018, Institute of Electrical Engineers of Japan (IEE Japan)

    Prof. Kazuhiro Umetani

  41. Extremum Co-Energy Principle for Analyzing AC Current Distribution in Parallel-Connected Wires of High-Frequency Power Inductors

    Article • IEEJ Journal of Industry Applications, January 2018, Institute of Electrical Engineers of Japan (IEE Japan)

    Prof. Kazuhiro Umetani

  42. Proposal for the New Control Method Having High Responsiveness and Robustness for the Boost-Type DC-DC Converter

    Article • IEEJ Transactions on Electronics Information and Systems, January 2018, Institute of Electrical Engineers of Japan (IEE Japan)

    Prof. Kazuhiro Umetani

  43. Elucidation of quasi-duality between series-series and series-parallel topologies of resonant inductive coupling wireless power transfer systems

    Article • December 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  44. Straightforward Measurement Method of Common Source Inductance for Fast Switching Semiconductor Devices Mounted on Board

    Article • IEEE Transactions on Industrial Electronics, October 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  45. A Lagrangian dynamics model of integrated transformer incorporated in a multi-phase LLC resonant converter

    Article • October 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  46. Analytical investigation on design instruction to avoid oscillatory false triggering of fast switching SiC-MOSFETs

    Article • October 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  47. Compact three-phase AC inductor network for PFC converter using magnetic coupled technique

    Article • October 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  48. Optimization of the balance between the gate-drain capacitance and the common source inductance for preventing the oscillatory false triggering of fast switching GaN-FETs

    Article • October 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  49. Simple self-driven synchronous rectifier for resonant inductive coupling wireless power transfer

    Article • October 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  50. Soft-switching technique applicable to capacitive load for resonant inverter of plasma generator

    Article • October 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  51. An investigation into a slight-variation of the transformer effective permeability in LLC resonant converter

    Article • September 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  52. Application of extremum co-energy principle for homogenizing current distribution in parallel-connected windings in transformers: Design optimization of winding turn allocation among winding layers

    Article • September 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  53. Total volume evaluation of high-power density non-isolated DC–DC converters with integrated magnetics for electric vehicles

    Article • IET Power Electronics, July 2017, the Institution of Engineering and Technology (the IET)

    Prof. Kazuhiro Umetani, jun imaoka, Prof. Wilmar Martinez

  54. Current ripple modeling of an interleaved high step-up converter with coupled inductor

    Article • June 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  55. Measurement of the common source inductance of typical switching device packages

    Article • June 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  56. A novel three-phase LLC resonant converter with integrated magnetics for lower turn-off losses and higher power density

    Article • March 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  57. Simple analytical derivation of magnetic flux profile eliminating source current ripple and torque ripple of switched reluctance motors for electric vehicle propulsion

    Article • March 2017, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  58. A design guideline of parasitic inductance for preventing oscillatory false triggering of fast switching GaN-FET

    Article • IEEJ Transactions on Electrical and Electronic Engineering, December 2016, Wiley

    Prof. Kazuhiro Umetani

  59. Quasi-Duality between SS and SP Topologies of Basic Electric-Field Coupling Wireless Power Transfer System

    Article • Electronics Letters, October 2016, the Institution of Engineering and Technology (the IET)

    Prof. Kazuhiro Umetani

  60. Copper loss analysis based on extremum co-energy principle for high frequency forward transformers with parallel-connected windings

    Article • October 2016, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  61. Simple control technique to eliminate source current ripple and torque ripple of switched reluctance motors for electric vehicle propulsion

    Article • October 2016, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  62. Three-phase LLC resonant converter with integrated magnetics

    Article • September 2016, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  63. Lagrangian derivation and analysis of a simple equivalent circuit model of wireless power transfer system with dual transmitting resonators

    Article • September 2016, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  64. Lagrangian method for deriving electrically dual power converters applicable to nonplanar circuit topologies

    Article • IEEJ Transactions on Electrical and Electronic Engineering, May 2016, Wiley

    Prof. Kazuhiro Umetani

  65. A simple behavior model for switched reluctance motors based on magnetic energy

    Article • May 2016, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  66. Magnetic Analysis, Design, and Experimental Evaluations of Integrated Winding Coupled Inductors in Interleaved Converters

    Article • IEEJ Journal of Industry Applications, January 2016, Institute of Electrical Engineers of Japan (IEE Japan)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  67. Time Evolution of an Urban Heat Island from High-Density Observations in Kyoto City

    Article • SOLA, January 2016, Meteorological Society of Japan

    Prof. Kazuhiro Umetani

  68. Simple flux-based Lagrangian formulation to model nonlinearity of concentrated-winding switched reluctance motors

    Article • Electronics Letters, November 2015, the Institution of Engineering and Technology (the IET)

    Prof. Kazuhiro Umetani

  69. High Step-Up Interleaved Converter for Renewable Energy and Automotive Applications

    Article • November 2015, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  70. A novel high step-down interleaved converter with coupled inductor

    Article • October 2015, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  71. Lagrangian-based equivalent circuit of basic electric-field coupling wireless power transfer system

    Article • IEEJ Transactions on Electrical and Electronic Engineering, October 2015, Wiley

    Prof. Kazuhiro Umetani

  72. Passive regenerative turn-off snubber composed of two diodes and a capacitor for two-phase interleaved boost chopper

    Article • October 2015, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  73. Mid-range kHz electric resonance coupling wireless power tranfser

    Article • September 2015, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  74. Non-isolated interleaved high step-up converter with reduced voltage multiplier stages and a regenerative turn-off snubber

    Article • September 2015, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  75. Analysis of coupled-inductor configuration for an interleaved high step-up converter

    Article • June 2015, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  76. Evaluation of the Lagrangian Method for Deriving Equivalent Circuits of Integrated Magnetic Components: A Case Study Using the Integrated Winding Coupled Inductor

    Article • IEEE Transactions on Industry Applications, January 2015, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  77. A Magnetic Structure Integrating Differential-Mode and Common-Mode Inductors with Improved Tolerance to DC Saturation

    Article • IEEJ Journal of Industry Applications, January 2015, Institute of Electrical Engineers of Japan (IEE Japan)

    Prof. Kazuhiro Umetani

  78. Lagrangian-Based Derivation of a Novel Sliding-Mode Control for Synchronous Buck Converters

    Article • IEEJ Journal of Industry Applications, January 2015, Institute of Electrical Engineers of Japan (IEE Japan)

    Prof. Kazuhiro Umetani

  79. A detection method of DC magnetization utilizing local inhomogeneity of flux distribution in power transformer core

    Article • September 2014, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  80. Integrated magnetic structure for EMC filter

    Article • May 2014, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  81. A unidirectional boost chopper with snubber energy regeneration using a coupled inductor

    Article • IEEJ Transactions on Electrical and Electronic Engineering, April 2014, Wiley

    Prof. Kazuhiro Umetani

  82. High power density DC-DC converter for home energy management systems

    Article • April 2014, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani, Prof. Wilmar Martinez

  83. Parasitic Resistance Analysis in a Novel High Step-Up Interleaved Converter for Hybrid Electric Vehicles

    Article • Journal of the Japan Institute of Power Electronics, January 2014, The Japan Institute of Power Electronics

    Prof. Wilmar Martinez, Prof. Kazuhiro Umetani

  84. Improvement of saturation property of iron powder core by flux homogenizing structure

    Article • IEEJ Transactions on Electrical and Electronic Engineering, September 2013, Wiley

    Prof. Kazuhiro Umetani

  85. Evaluation of the Lagrangian method for deriving equivalent circuits of integrated magnetic components: A case study using the integrated winding coupled inductor

    Article • September 2013, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  86. Characteristics analysis and performance evaluation for interleaved boost converter with integrated winding coupled inductor

    Article • September 2013, Institute of Electrical & Electronics Engineers (IEEE)

    Prof. Kazuhiro Umetani

  87. A generalized method for Lagrangian modeling of power conversion circuit with integrated magnetic components

    Article • IEEJ Transactions on Electrical and Electronic Engineering, November 2012, Wiley

    Prof. Kazuhiro Umetani

  88. A Practical Pyrgeometer Using the Representative Angle

    Article • Journal of Atmospheric and Oceanic Technology, March 2009, American Meteorological Society

    Prof. Kazuhiro Umetani

  89. A new technique of radiation thermometry using a consumer digital camcorder: Observations of red glow at Aso volcano, Japan

    Article • Earth Planets and Space, February 2005, Springer Science + Business Media

    Prof. Kazuhiro Umetani