Copula Theory Based Calculation Method of Fault Probability Under Typhoons Disaster

Extreme natural disasters like typhoons, occurs infrequently but cause serious damage. However, typhoons are often accompanied by heavy rainfall, which may also cause line breaks and fallen towers. In this paper, a method for calculating the fault probability under typhoons and rainstorms using Copula theory and Generalized Pareto Distribution (GPD) is proposed. First, based on GPDs of wind speed and rainfall under typhoon weather, the calculation models of wind and rain loads are proposed. Furthermore, considering the relevance between wind and rain loads imposed on towers and power lines, a joint probability distribution calculation model for wind and rain loads is proposed using Copula theory. On this basis, the probability calculation of line breaks and towers fallen under typhoon disaster is realized. Finally, the proposed method is validated by comparing with the fault probability calculation methods without considering coupling of wind speed and rainfall.