Johann Walter Kolar receives the IEEE Medal in Power Engineering
An IEEE Life Fellow, IES member Prof. Johann Walter Kolar is the 2025 IEEE Medal in Power Engineering recipient “for pioneering contributions to and leadership in power electronics systems, grid interfacing technologies, and ultra-high-speed motor drives.”
The IEEE Medal in Power Engineering, sponsored by the IEEE Industry Applications, Industrial Electronics, Power Electronics, and Power & Energy societies, is presented to an individual for outstanding contributions to the technology associated with the generation, transmission, distribution, application, and utilization of electric power for the betterment of society.
Johann Walter Kolar, Professor Emeritus, Department of Information Technology and Electrical Engineering, ETH Zürich, Switzerland
Prof. Johann W. Kolar is an internationally acclaimed researcher and a towering figure in the field of power electronic systems. He is regarded as the “father” of high-frequency multi-phase AC/DC converter technology, which finally allowed the electronic linking of the AC and DC electric power distribution empires created by Thomas A. Edison and George Westinghouse. Early on, he saw the critical importance of power electronic converters and pursued a vigorous research program laying the foundation for research on high-power quality, compact, and efficient rectifier systems. In 1993, he invented the Vienna Rectifier (VR), which has since become a standard solution for high-efficiency datacenter power supply and, in its bidirectional extension, for the integration of solar power into the AC grid. Kolar was also among the first to propose and develop partly phase-modular three-phase AC/DC converter systems, the preferred approach for today´s onboard electric vehicle (EV) battery chargers. He also developed the X-Rectifier concept, another groundbreaking invention with large potential to enable major applications, including the interconnection of local DC-microgrids to three-phase AC mains. For the past two decades, Kolar has spearheaded research on quasi-single-stage isolated AC/DC converter systems and Solid-State Transformers (SSTs), paving the way for the next generation of medium-voltage power supplies for hyperscale data centers. Kolar continues to make extraordinary contributions to power electronics and power conversion technologies, placing him among the rare global visionaries helping shape the future of the electricity industry and energy technologies.
Congratulations to him!