Risk-based transmission lines importance calculation under ice storm weather

A risk-based transmission lines importance calculation method is proposed under ice storm to identify the importance of icing lines to system operation in this paper. The model of forced outage rate of icing line is established by load-strength interference theory. Then risk functions of demand not supplied and power failures are established. The concept of transmission lines´ global sensitivity of risk functions is proposed to quantify the influence of icing lines to system operation by analysis of variance decomposition. The quasi-Monte Carlo method based on Sobol´ sequence is used to calculate global sensitivity of icing lines. The proposed method is tested on the system of IEEE RTS79. The results show that different lines have various importance to system risk and the importance sorting of icing lines could be a feasible tool to help arrange the deicing work.