Multi-Engine in Modular Multilevel Converter based Split Battery Systems for Electric Vehicles

Usually all electric traction engines in electric vehicles (EV) are generated out of the high voltage DC-BUS by a dedicated DC/AC converter. When the conventional drive train or engine converters are substituted by a modular multilevel converter with split batteries, this DC-BUS is obliterated. In this paper an approach to easily supply a number of engines based on the modular concept is presented. Just by adding, one module per engine to each converter arm, a solution for an efficient bidirectional energy exchange between the engines and the traction battery can be realized. It will be shown by simulations, that an implementation based on that technology enables a supply of each engine in any operation point of the electrical vehicle. The technology presented here requires bidirectional switches on the motormoduls.