A Reconfigurable Topology for Integration of Removable Batteries in an Electric Powertrain With 400 V and 800 V Compatibility

Abstract

Electric vehicles (EVs) are a sustainable solution for transportation, which on-board batteries play a fundamental role. To enhance the flexibility of EV energy management and contribute to overall performance improvements in the electric powertrain, the integration of a removable battery emerges as an alternative approach. This solution is suitable for both the widely adopted 400 V bus standard and the emerging 800 V standard, which is gaining acceptance in the commercial vehicle market due to its promising features. This paper presents a reconfigurable topology with the ability to connect a removable battery to both the 400 V and 800 V buses. An externally charged removable battery offers an additional level of flexibility, allowing for external charging and the option to adjust the EV capacity based on the chosen route. The proposed reconfigurable topology can operate at both the 400 V and 800 V standards without any external switch to adapt to each voltage level. Thanks to the modularity of the proposed technology, voltage and current maximum ratings of the semiconductors are not increased due to the use of the 800 V standard. The topology is based on the Dual Active Bridge (DAB) converter utilizing the Input Parallel Output Parallel (IPOP) and the Input Parallel Output Series (IPOS) configurations. Experimental results on a downscaled prototype demonstrate the performance and feasibility of the reconfigurable topology.