Impact Analysis of Equivalent Electrical Models for Supercapacitor Energy Storage Systems in Urban Rail Transit

The widespread adoption of supercapacitor regenerative braking energy recovery systems in urban rail transit has give a significant attention regarding on the evaluation of energy savings and voltage stabilization effects of traction power supply networks. This study analysis the impact of supercapacitor electrical models and parameter selection on these effects. Initially, a comparative analysis is conducted between the linear model and the nonlinear branch model of supercapacitor, with parameter identification performed using Arbin test rig. Subsequently, typical operating conditions from a Beijing subway line are used to simulate and analyze the energy-saving rate and voltage stabilization rate of various electrical models, leading to the selection of the most suitable model for evaluation. Finally, the energy-saving rate and voltage stabilization rate under different series-parallel configurations of individual cells are compared under a fixed supercapacitor system capacity configuration.