Transmission network chain fault path based on coupling of typhoon disturbance and line vulnerability

The chain failure analysis of power transmission networks under the combined influence of typhoon disturbances and the vulnerability effects of transmission lines was examined. Typhoons serve as the external cause triggering natural disasters, while the line’s vulnerability effects and domino-like cascading failures represent the internal causes. Initially, the study investigates the mechanism by which the changing wind direction and velocity of typhoons induce oscillations in transmission towers and lines, leading to disasters such as tower swaying and conductor galloping. Additionally, the research explores the internal mechanisms of transmission lines and equipment facilities in service, focusing on the degradation of material mechanical properties under frequent multi-frequency and multi-amplitude external force loads and the weakening of equipment reliability due to climatic conditions over time. The combined impact of these dual causes on system failure rates and safe overload capacities is analyzed. Subsequently, the Batts typhoon wind field model and the transmission tower and line vulnerability model are established. By integrating the probability indicators of line failures caused by the dynamic path of typhoons and the correlation indicators of power flow fluctuations obtained from AC power flow analysis, the model identifies the next-level failure elements. A multi-temporal dimension failure evolution model is constructed, linking the time dimension of typhoon action with the time dimension of transmission line vulnerability effects. Finally, the proposed algorithm is analyzed and verified using the IEEE 39-node system case study and the “623 Tornado” accident in Yancheng, Jiangsu. The analysis demonstrates a strong correlation between the cascading failure paths of the power transmission network and the dynamic path of severe typhoons, validating the effectiveness and acceleration of the proposed method. This translation aims to maintain the original meaning while elevating the language to a more academic and refined level.