Research On The Seismic Safety And Resilience Evaluation Theory Of Power Grid

Power grid is an important part of the urban engineering system,which plays an vital role in social production,resident daily life and all other social activities.Once the power grid damaged to result in failing to maintain normal power supply,it will have a serious impact on the post-disaster emergency rescue and fast reconstruction,which causes a greater loss.Most of the seismic research of grid facilities or equipment foucs on seismic capacity of grid element(facility or equipment),seismic vulnerability,shock absorption and isolation,disaster loss assessment and reliability analysis of grid,but not much of whether grid can maintain operation and continuous power supply safely or quickly recover from the earthquake.At present,we still don't know how to evaluate the capacity of power facilities or equipment in earthquake to maintain safe operation and the strength of the recovery ability.Based on the vulnerability research results of facilities or equipment in power grid,further evaluation on the ability to maintain safe operation as well as the ability to recover in time from the earthquake should be maken,which is an important premise to improve the seismic safety of power grid and accelerate the post-earthquake recovery progress.To solve these problems,the following work were carried out in this paper:(1)The composition of power grid and seismic damage characteristics of power facilities or equipment were introduced.Then,the current research states about safety evaluation,resilience theory and seismic vulnerability,seismic safety and seismic resilience of power grid at home and abroad are summarized.(2)The seismic vulnerability results of power facilities in the Wenchuan earthquake were statistically given.The related concepts and meaning of seismic safety were interpreted.The main influence factors of substations and transmission lines seismic safety were analyzed.Then,the seismic safety index of substation and transmission lines were put forward.The seismic safety grades classification methods of substations and transmission lines were studied respectively.The seismic safety of subatstions and transmission lines were both divided into four grades: excellent,good,moderate,poor.(3)The relationship between the seismic vulnerality and recovery time of electric power facilities was statistically given.The seismic resilience of substation was defined,and the seismic resilience was divided into four grades: excellent,good,moderate,poor.The seismic resilience index of substation and its calculation formula were put forward.According to the calculation formula,the seismic resilience index of 102 substations samples were calculated,and the corresponding relationship between resilience index and resilience grades was found out.Besides,the relationship among seismic resilience index,intensity and recovery time of substation was also analyzed.Based on the resilience index calculation results of substations samples,the substation resilience matrix was statistically established.Finally,the rapid evaluation model of substation seismic resilience was put forward.(4)The recovery progress of transmission lines in the areas of mianyang and deyang were estimated.As a result,the corresponding recovery progress figures were ploted.The seismic resilience of transmission lines was divided into four grades as well as substations,excellent,good,moderate,poor.The seismic resilience index of transmission lines was defined,and resilience index of 213 transmission lines in wenchuan earthquake disasters areas of aba,guangyuan and mianyang were calculated.The relationship between seismic resilience index and intensity was analyzed.Based on the resilience index calculation results of transmission lines samples,the transmission lines resilience matrix was established.Finally,the rapid evaluation model of transmission lines seismic resilience was put forward.(5)Taking the power grid in Kelamayi district as an example,the respective seismic safety index and seismic resilience index of 22 substation and 33 transmission lines were calculated,which were used to evaluated the corresponding seismic safety grades and seismic resilience grades.The evaluation methods of overall power grid seismic safety and seismic resilience were developed,and the seismic safety grades and seismic resilience grades of power grid in Kalamayi district were respestively determined.