Non-conventional supplying system for induction traction motors from Diesel locomotives

The evolution of the power electronic devices (with proper control strategies) enables the replacement of the DC traction motor with the more advantageous induction motor in railway application. The AC traction motors ask for expensive, intricate inverters with semiconductors working under high electric stress. For the Diesel-electric locomotives, the authors propose an original non-conventional supplying system for AC motor with reduced stress of the power semiconductors. The main idea is to replace the conventional three-phase inverter with a three-phase power circuit operating as matrix-converter or, more proper, as "cyclo-converter". The paper presents the principle of operation of this new supplying system and gives some results of the digital simulation in Matlab-Simulink.