System test of a 1-MVA-HTS-transformer connected to a converter-fed drive for rail vehicles

Railway companies aim to realize environmentally friendly revenue operations with high efficiency. High Temperature Superconducting (HTS)-transformers offer advantages regarding less mass and volume and considerably higher efficiency in drive systems. Siemens has developed a 1-MVA-HTS-transformer with typical characteristics for railway applications. For a successful introduction in the market, it is essential to guarantee the operational behavior of drive systems in well-known manner. So, Siemens realized the 1st operation of an AC-converter fed by a HTS-transformer. System test measurements of losses, tests of cooling redundancy as well as drive cycle operation were performed to compare the converter operation to sinusoidal operation, to analyze the losses depending on the harmonics of nonsinusoidal current and to investigate the behavior of the whole system under realistic drive cycles of a current rail vehicle.