Volume 49

Stability analysis of a multi-terminal DC system considering the stochastic state of electric vehicles Yin Yi, Yun Zhou, Ning Ma, Donghan Feng, Yuanhao Feng, Wenhang Yin

Abstract

The proliferation of DC charging stations is increasing steadily, and the integration of multi-terminal DC systems is a crucial prerequisite for facilitating the charging of electric vehicles with direct current. The stochastic charging state of electric vehicles present a formidable challenge to the stability of DC systems. This research focuses on a multi-terminal DC system with N electric vehicles as its primary subject. To assess the system’s stability in the face of the stochastic charging state of N vehicles, a small signal stability analysis method that relies on reduced order matrixes is employed. Moreover, a novel numerical index is introduced to quantitatively evaluate the risk of instability, offering valuable insights for formulating effective charging control strategies. To validate the effectiveness of the proposed method, a nonlinear time domain model is constructed in Simulink and subjected to rigorous testing.

Keywords multi-terminal DC system, stochastic charging state, small signal stability analysis, instability risk