Equivalent Circuit for LVDC Grid Fault Analysis: Physical Parameters Evaluation

Traditional DC fault analysis approaches are effective primarily for cases involving very low-impedance faults or unusually simple systems, limiting their applicability. Recent advancements in DC fault analysis showed enhanced accuracy, flexibility, and are applicable to complex grid configurations and non-zero fault impedance scenarios. Nevertheless, these methods require to analyze the entire network for any fault to be considered, which can be impractical and computationally demanding. To address this issue, this paper explores the possibility of modeling a portion of an LVDC system by a simple RLC circuit, the parameters of which are determined by a straightforward analytical approximation relying on the main physical parameters of the whole DC grid. The proposed method produces a simple equivalent circuit, which is shown to reliably approximate the grid's fault behavior.