Research On The Method Of Transmission System Resilience Assessment For Extreme Typhoon Disaster

Global climate change leads to the increase of extreme typhoon weather.Transmission system is an important link connecting power generation and electricity consumption,which is vulnerable to the impact of extreme typhoon weather.The resilience of power system is an important parameter used to evaluate the performance change of power grid under extreme disaster conditions.The study of transmission system resilience evaluation can quantify the response ability of the system to disasters and help to reduce the occurrence of large-scale power outages.In this paper,the response process of the transmission system under extreme typhoon weather is simulated,the resilience of the transmission system is analyzed and quantified,and the resilience of the grid is improved by recovery strategy based on the critical lines.The main work and achievements are as follows:Typhoon model and power system model were proposed.According to the typhoon wind field model,the maximum wind speed and maximum wind radius models of typhoon are established from the time dimension.In the spatial dimension,the network grid method is used to form the disaster zone model.Based on the structural reliability analysis,the failure rate curves of transmission towers and conductors are established.A post-disaster component repair time model was established considering the location of components,weather conditions and repair strategies.The above model is used to study the line failure rate under typhoon weather in IEEE6 bus system,and the influence process of extreme weather on the components and the whole transmission system is illustrated,and the availability of the proposed model is verified.To solve the problem of generating fault scenarios under extreme typhoon conditions,Markov Chain Monte Carlo method(MCMC)sampling method is proposed,and the simulation process of transmission network performance during typhoon invasion stage is studied.In order to make up for the deficiency of Monte Carlo simulation method(MC),MCMC is used to sample the fault state scenarios of transmission system.Fault scenarios are reduced based on fast forward selection method.According to the sampling results,the system performance loss is calculated based on optimal power flow.A numerical example is given to verify the advantages of MCMC method in convergence performance,and the system load loss under the action of typhoon is analyzed.In order to study the resilience of transmission system in the whole response process and realize the identification and positioning of key components,a complete resilience evaluation process and identification method of key facilities are proposed.The resilience assessment framework integrates weather scenarios,component states,and system responses.In order to quantify resilience,a multi-dimensional infrastructure and operational resilience index and a global maximum flow index are proposed.The maximum flow contribution can be used to identify the critical lines and optimize the repair order.The IEEE 30 bus system demonstrates the effectiveness of the resilience index,and verifies the role of the system critical line identification technology in improving the resilience of the system.