Auxiliary Professor in the Department of Electrical Engineering, Faculty of Science and Technology, Universidade NOVA de Lisboa, Portugal

Research interests:
power converters, energy harvesting, wireless energy transfer, electric vehicles, energy management and storage, non-destructive testing, bio energy-harvesting, and biosensors

Keynote address:
Renewable Energy Invasion Requires Both DC Grid and Wireless Energy Transfer

The traditional world-wide power system is based on AC energy, having to fight the consequences, e.g. the synchronization, the reactive power, etc. The invasion of the renewable energy makes that classic fight more difficult, but the renewable energy sources are mostly DC, or easily transferable into a DC power supply. This invasion made more realistic a future DC grid, which has no need of synchronization, neither has reactive power problems. The Low Voltage (LV) DC grid is prepared to be a Smart Grid, even reaching now 800 V or more. The EU rules permit the LV to be made even up to 1500 V, which permits much higher efficiency. At this point start the problems of the dangerously high values of that DC voltage. In the same time it can be proved that the DC-DC conversion is always using the magnetic field as a power link. The difference between the "normal" and the wireless DC-DC converter is only the percentage of the magnetic coupling. The magnetic field connections of the renewable energy sources will be more reliable and less dangerous for the human beings and the animals.

Stanimir VALTCHEV was born in Bulgaria 1951, received M.Sc. from TU Sofia, awarded as the best of the year 1974, received PhD from IST in Lisbon. He worked on semiconductor technology, medical equipment, and then as a researcher in industrial electronics (laser supplies and high-frequency power converters). In the 1980s worked in the Robotics Laboratory of TU Sofia (also being Assistant Director of the Centre of Robotics). During 1987 and in 1991-1992 he worked in the Laboratory for Power Electronics of TU Delft in the Netherlands, as Assistant Professor. Since 1988 was Assistant Professor in TU Sofia and taught several courses on Power Supply Equipment and Power Transistor Converters to graduate and post-graduate students. He was the Deputy Dean of TU Sofia, responsible for the international students in 1990-1994. After 1980 he worked on high-frequency resonant power converters and published in numerous conferences and journals (IEEE Meritorious Paper Award, 1997). In 1994 being invited to Portugal to lead a project of a new soft-transition power converter, stayed and taught various subjects in different universities and has consulted various institutions in Portugal and in the Netherlands. He is currently Auxiliary Professor in UNL and Invited full professor in BFU, Bulgaria. His research includes power converters (also resonant and multilevel), energy harvesting, wireless energy transfer, electric vehicles, energy management and storage, bio energy-harvesting, and biosensors.

DAS 2014
Keynote Speaker

IEEE Senior member



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