This paper presents an PSO-based optimization methodology for estimating the capacities and initial SOC of an energy storage systems (ESSs) in a DC electric railway system. The proposed method calculates the optimal solution using the missing capacity caused by the limited storage capacity. The missing capacity can be estimated through continuous-powerflow analysis. In many previous studies, capacities was calculated by assuming the each ESS as an independent device. However, since each storage device affects the charging and discharging operation of each other, this assumption might affect the convergence characteristics. In this paper, to solve this problem, the missing capacity of the ESS at both sides is reflected by using the relating coefficient derived based on the electrical distance between storage devices. The case studies show that the most efficient operation without missing capacity is possible under the derived capacities and initial SOC.

本文提出了一种基于PSO的优化方法，用于估算直流电铁路系统中储能系统（ESS）的容量和初始SOC。所提出的方法利用有限的存储容量导致的容量不足来计算最佳解决方案。可以通过连续潮流分析来估算缺少的容量。在以前的许多研究中，通过将每个ESS假定为独立设备来计算容量。但是，由于每个存储设备都会影响彼此的充电和放电操作，因此该假设可能会影响会聚特性。在本文中，为解决此问题，通过使用基于存储设备之间的电气距离得出的相关系数来反映ESS两侧的缺失容量。