Novel Power Converters for Reconfiguration and Voltage Balancing of Dual Battery Pack Based EV

Abstract

Battery Electric Vehicles predominantly come with a single battery pack. Reliability and limited driving range are the main obstacles to EV market growth. To overcome these, dual battery pack-based EVs are seen as a promising alternative for the future. This paper presents two novel power converters suitable for dual battery pack-based Electric Vehicles. The proposed converters can configure and connect two battery packs in series or parallel or operate with a single battery pack. The output terminals of the proposed converters can be connected directly to the charger terminal during charging or to the motor drive inverter during traction. When the EV is neither in charging mode nor in traction mode, and if there is a voltage imbalance between the two battery packs, proposed converters can transfer power from the battery pack with a higher terminal voltage to the other one. The converters' transfer function is derived using state-space averaging and small-signal modeling to design the converter's controller in the voltage balancing mode. The controller is designed using the K-factor approach. Detailed MATLAB simulations and hardware experiments are presented to validate the efficacy of proposed converters in different operating modes. © 2022 IEEE.