Mid-Frequency 6.5 kV Series Resonant Converter for Traction Applications

NYU Community Event

Speaker: Rodrigo Alvarez and Lars Lindenmüller 

Host Faculty: Professor Francisco De Leon


Due to historical reasons, in Germany as well as in other European countries, most of the railway is electrified with a single phase 15 kV, 16.7 Hz overhead wire. This means in conventional traction systems that a very large and heavy input transformer is required. To reduce weight and increase the efficiency in traction applications several power electronics based solutions have been proposed. Amongst them is the so called medium frequency topology (or power electronic transformer). Key element of this topology is a high power, medium voltage series resonant converter (SRC), that provides an isolation barrier with a transformer operated at several kilohertz. Using HV-IGBTs here is especially challenging since the switching frequency is approximately 20 times higher than in other typical, hard switching, applications where these devices are employed. In the presentation, different ways to reduce the switching losses, as well as a method to optimize the converter in a given application (apart from traction, the SRC can be employed in applications such as high power offshore wind or back-to-back networks) are shown.

About the Speakers

Rodrigo Alvarez born in Santiago, Chile, received the Electronic Eng. and M. Sc. degree in Power Electronics from the Universidad Técnica Federico Santa María (UTFSM), Valparaiso Chile, in 2006. In 2007 he joined the Power Electronics group at the Dresden Technical University, where he received the Dr.-Ing degree in Power Electronics in 2011. He is currently working as senior scientist with the Power Electronics group at the Dresden Technical University, leading several strategic power electronics research projects for low voltage high power and medium voltage applications.

Lars Lindenmüller received the Diploma degree in Electrical Engineering from the Technische Universität Dresden, Germany, in 2009. Since then he is with the Power Electronics group and is currently working towards his Ph.D. degree. His research interests include high power resonant converters, applications of HV-IGBTs, multilevel topologies and traction applications.