Modelling and computer simulation analysis of cascading failure probability of heterogeneous complex power grid for green energy system

The high proportion of renewable energy integration endows the power grid with prominent heterogeneous features, including expanded node capacity differences, discrete line impedance, and dynamic power flow variations. Traditional models based on homogeneity assumptions are incompetent to accurately characterise the cascading failure mechanisms of such grids. To address this gap, this paper proposes a cascading failure probability model that integrates heterogeneous topology, dynamic power flow, and cyber-physical coupling. Firstly, a multi-dimensional heterogeneity indicator system, encompassing node capacity heterogeneity, electrical betweenness Gini coefficient, and bidirectional power flow index, is established to quantify the structural, operational, and coupling heterogeneity of green power grids. The results provide theoretical basis and quantitative tools for planning and real-time prevention and control of highly elastic green power grid.