Philip T. Krein

Electrical and Computer Engineering
Research Professor
  • Electrical and Computer Engineering
4050 ECE Building
306 North Wright Street
Urbana Illinois 61801
Grainger Endowed Chair Emeritus
4050 ECE Building
306 North Wright Street
Urbana Illinois 61801

Primary Research Area

  • Power and Energy Systems

For more information



  • Ph.D. Electrical Engineering University of Illinois 1982


Philip T. Krein received the B.S. degree in electrical engineering and the A.B. degree in economics and business from Lafayette College, Easton, Pennsylvania, and the M.S. and Ph.D. degrees in electrical engineering from the University of Illinois, Urbana. He was an engineer with Tektronix in Beaverton, Oregon, and then returned to the University of Illinois at Urbana-Champaign. At present, he is the Grainger Endowed Director’s Chair Emeritus in Electric Machinery and Electromechanics as Professor Emeritus and Director of the Grainger Center for Electric Machinery and Electromechanics. He is also the founding Executive Dean of the Zhejiang University/University of Illinois at Urbana-Champaign Institute, founded in 2016. His research interests address all aspects of power electronics, machines, drives, transportation electrification, and electrical energy, with emphasis on nonlinear control approaches. He published an undergraduate textbook, Elements of Power Electronics (Oxford University Press, second edition 2015). In 2001, he helped initiate the International Future Energy Challenge, a major student competition involving fuel cell power conversion and energy efficiency. From 2008 through 2015 he chaired the New Building Committee in the Department of Electrical and Computer Engineering, and contributed several energy and design innovations to the new ECE Building at Illinois. He holds thirty-seven U.S. patents with additional patents pending.

Dr. Krein is a registered professional engineer in Illinois and in Oregon. He was a senior Fulbright Scholar at the University of Surrey in the United Kingdom in 1997-98, and was recognized as a University Scholar in 1999, the highest research award at the University of Illinois. In 2003, he received the IEEE William E. Newell Award in Power Electronics. In 1999-2000 he served as President of the IEEE Power Electronics Society. In 2003-2004 he was a member of the IEEE Board of Directors. From 2003-2014 he was a member of the board of directors of SolarBridge Technologies, the leading innovator of integrated ac solar panels. He was elected to the U.S. National Academy of Engineering in 2016. He is an Associate Editor for the IEEE Transactions on Power Electronics and for the IEEE Journal of Emerging and Selected Topics in Power Electronics. In 2005-2007, he was a Distinguished Lecturer for the IEEE Power Electronics Society. In 2015-2016, he was Chair of the IEEE Transportation Electrification Community.

Academic Positions

  • Executive Dean, Zhejiang University/University of Illinois at Urbana-Champaign Institute, Haining, China, May 2016 to present.

Teaching Statement

Prof. Krein initiated a complete curriculum in modern power electronics, and has taught project courses such as hybrid and electric vehicles, design of efficient motors for appliances, and others. He designed and developed laboratory facilities and courses used in these subject areas and had heavy involvement in the design and implementation of energy features in the new ECE Building. Energy is one of the most important interdisciplinary topics, and power electronics is the modern actuation method for all advanced energy systems.

Research Statement

Power electronics is the central enabling technology for advanced energy applications. It is a vital part of alternative and renewable energy conversion, hybrid and electric transportation, portable devices, efficient motors and appliances, new lighting technologies, and an increasing range of industrial processes. Research at Illinois in this area seeks to identify the best methods, best materials, and best engineering practices for the conversion and control of electrical energy. The research also covers dominant application areas, including electric machinery and electromechanics. Approaches such as correlation-based controls, high-performance geometric control and operating methods, design approaches for extreme reliability, and simple ways for wide-range operation of power converters have been developed at Illinois. New approaches to the design of electric machines are being explored. Work on systems and system integration has included plug-and-play solar power systems, electric and hybrid vehicle modelling, development of wide bandgap power semiconductors, and new ways for power processes to support computation processes. Emerging work in low-energy buildings is another important application area.

Post-Doctoral Research Opportunities

Post-doctoral students interested in high-performance power electronics and electric machines can be supported by the engineer-in-residence program of the Grainger Center for Electric Machinery and Electromechanics, or should inquire about opportunities at the Zhejiang University/University of Illinois Institute.

Graduate Research Opportunities

Each of the five thematic areas listed in the Annual Statement of Research Progress has opportunities for graduate research assistantships.

Undergraduate Research Opportunities

Each year, several undergraduate students are supported to conduct research within the Grainger Center for Electric Machinery and Electromechanics (CEME). Activities range from circuit board layout and construction to advanced research projects. Students work side by side with graduate students and faculty to carry out experimental activities in energy, electromechanics, and power electronics. CEME has one of the largest undergraduate research programs in the department.

Research Interests

  • Energy efficient buildings.
  • Alternative and renewable energy systems.
  • Transportation electrification.
  • Electric machinery and electromechanics.
  • Power electronics.

Research Areas

Books Authored or Co-Authored (Revisions)

  • P. T. Krein, Elements of Power Electronics, second edition, Oxford University Press, New York, 2015.

Selected Articles in Journals

  • K. A. Kim, G.-B. Seo, B.-H. Cho, P. T. Krein, "Photovoltaic Hot-Spot Detection for Solar Panel Substrings Using AC Parameter Characterization," IEEE Trans. Power Electronics, vol. 31, no. 2, pp. 1121-1130, 2016.
  • V. T. Buyukdegirmenci, P. T. Krein, "Induction Machine Characterization for Short-Term or Momentary Stall Torque," IEEE Trans. Industry Applications, vol. 51, no. 3, pp. 2237-2245, 2015.
  • A. M. Bazzi, P. T. Krein, "Ripple Correlation Control: An Extremum Seeking Control Perspective for Real-Time Optimization," IEEE Trans. Power Electronics, vol. 29, no. 2, pp. 988-995, 2014.
  • P. S. Shenoy, K. Kim, B. Johnson, P. T. Krein, "Differential Power Processing for Increased Energy Production and Reliability of Photovoltaic Systems," IEEE Trans. Power Electronics, Vol. 28, no. 6, pp. 2968-2979, June 2013.
  • P. S. Shenoy, P. T. Krein, "Differential Power Processing for DC Systems," IEEE Trans. Power Electronics, vol. 28, no. 4, pp. 1795-1806, April 2013.
  • P. T. Krein, R. S. Balog, M. Mirjafari, "Minimum Energy and Capacitance Requirements for Single-Phase Inverters and Rectifiers Using a Ripple Port," IEEE Trans. Power Electronics, vol.27, no.11, pp.4690-4698, Nov. 2012.
  • S. Kapat, P. Shenoy, P. T. Krein, "Near Null Response to Large-Signal Transients in an Augmented Buck Converter: A Geometric Approach," IEEE Trans. Power Electronics, vo. 27, no. 7, pp. 3319-3329, July 2012.
  • M. Amrhein, P. T. Krein, "Induction Machine Modeling Approach Based on 3-D Magnetic Equivalent Circuit Framework," IEEE Trans. Energy Conversion, vol. 25, no. 2, pp. 339-347, 2010.
  • J. W. Kimball, P. T. Krein, "Discrete-Time Ripple Correlation Control for Maximum Power Point Tracking," IEEE Trans. Power Electronics, vol. 23, no. 5, pp. 2353-2362, September 2008.

Teaching Honors

  • Incomplete List of Teachers Ranked as Excellent, multiple terms.
  • Published an undergraduate textbook for power electronics, 1998, 2015.

Research Honors

  • Thirty-seven U.S. and four European patents awarded.
  • Election to U.S. National Academy of Engineering, 2016.
  • Best Paper Award, IEEE Transportation Electrification Conference, 2015.
  • Best Paper Award, International Telecommunications Energy Conference, 2007.
  • Distinguished Lecturer, IEEE Power Electronics Society, 2005 to 2007.
  • IEEE William E. Newell Power Electronics Award, 2003.
  • Grainger Endowed Director's Chair in Electric Machinery and Electromechanics, 2002 to present.
  • IEEE Third Millennium Medal, 2000.
  • Fellow, IEEE, 2000.
  • University Scholar, 1999-2002.
  • Henry Ford II Scholar Award.

Public Service Honors

  • Chair, IEEE Transportation Electrification Community, 2015-2016.
  • Chair, IEEE Technical Activities Board Nominations and Appointments Committee, 2007.
  • Elected as IEEE Division II Delegate and member of the IEEE Board of Directors, 2003-2004.
  • President, IEEE Power Electronics Society, 1999-2000.

Courses Taught

  • ECE 431 - Electric Machinery
  • ECE 464 - Power Electronics
  • ECE 469 - Power Electronics Laboratory
  • ECE 568 - Model & Cntrl Electromech Syst
  • ENG 198 - Personal Mobility Innovations