Cascading failure analysis of power flow on wind power based on complex network theory

Cascading failure is a potential threat in power systems with the scale development of wind power, especially for the large-scale grid-connected and long distance transmission wind power base in China. This introduces a complex network theory (CNT) for cascading failure analysis considering wind farm integration. A cascading failure power flow analysis model for complex power networks is established with improved network topology principles and methods. The network load and boundary conditions are determined to reflect the operational states of power systems. Three typical network evaluation indicators are used to evaluate the topology characteristics of power network before and after malfunction including connectivity level, global effective performance and percentage of load loss (PLL). The impacts of node removal, grid current tolerance capability, wind power instantaneous penetrations, and wind farm coupling points on the power grid are analyzed based on the IEEE 30 bus system. Through the simulation analysis, the occurrence mechanism and main influence factors of cascading failure are determined. Finally, corresponding defense strategies are proposed to reduce the hazards of cascading failure in power systems.