TRANSFORMER: ABB has developed a traction transformer that uses power electronics to reduce size and weight while increasing energy efficiency.

The Power Electronic Traction Transformer is based on multi-level converter topology that uses IGBT power semiconductors and medium-frequency transformers to replace the conventional transformer and inverter combination. The medium-frequency transformer also reduces noise levels.

The pilot application of PETT is a 4500 kg unit with a nominal rating of 1·2 MW and short-term peak of 1·8 MW which has been fitted to a 15 kV 16·7 Hz Swiss Federal Railways Ee933 shunting locomotive used at Genève Cornavin station.

‘The innovative use of power semiconductors in a core component such as traction transformers opens up new opportunities for rail markets around the world, and should be extendable across a range of other applications,’ according to Markus Heimbach, head of the Transformers business within ABB’s Power Products division. ‘In addition to its weight and size advantages, the new PETT helps improve efficiency and reduces noise levels.'