Optimal Configuration of Dual-Battery Energy Storage Capacity for Traction Power Supply System Based on Life Cycle Cost

To address the problem of excessive life loss of energy storage system (ESS) caused by achieving peak traction load reduction and regenerative braking energy recovery, a method for optimal configuration of dual battery capacity of traction power supply system (TPSS) based on life cycle cost (LCC) is proposed. Firstly, a dual-battery energy storage system (DBESS) operation mode with separate execution of charging and discharging tasks is adopted to establish a charging and discharging model for the DBESS; Then, considering the effects of depth of discharge (DOD) and the number of frequent charge/discharge transitions on the battery service life and total energy transfer during the independent operation of dual batteries, a two-layer optimization model is established with the objective of minimizing the LCC and daily operation cost of DBESS, and the optimal capacity configuration and optimal operation strategy of DBESS are obtained; Finally, the effectiveness of the DBESS connected to the TPSS is verified by simulation analysis.