Investigation of integrated e-Axle solutions for automotive propulsion electrified applications

This thesis activity is focused on the investigation of integrated e-Axle solutions, also called 3in1 for electrified vehicles (EVs and HEVs). This modular element is made of the reversible electric motor, the mechanical transmission and the bidirectional DC/AC converter, also called inverter. The investigation starts with a brief description of the components of the e-Axle, followed by the state of the art analysis both for passenger cars and heavy duty vehicles. Following on, the transmission design is described both for single-speed and two-speeds arrangement. The same is for the e-motors related to the two speeds transmission solutions for a small Class A passenger car. A brief description of the inverter and a simple cost evaluation (focused on the e-motor materials) is presented. As last step, the two new solutions are evaluated at simulation level using as reference a Fiat 500e with its e-powertrain in terms of accelerating performance with different target speed and range/energy consumption on the WLTP homologation cycle. At the end the conclusions and the next possible future improvement and refinement steps are presented.