考虑材料不确定性的特高压GIS瓷套管地震易损性研究

Study on Seismic Vulnerability of Porcelain Bushing for Ultra⁃high⁃voltage GIS Considering Material Uncertainty

为更准确地评估材料不确定性对电气设备地震易损性的影响,以某型特高压气体绝缘开关(gas insulated switchgear,GIS)瓷套管为例,建立经过振动台试验验证的套管有限元模型,在考虑地震动不确定性的同时对材料参数随机变量进行抽样,开展地震易损性分析。对比考虑材料不确定性前后特高压GIS瓷套管地震易损性,探究材料不确定性对电气设备抗震性能与地震易损性的影响。结果表明:引入材料不确定性后特高压GIS瓷套管的地震易损性将发生小幅度改变,并且离散程度增大。在地震易损性分析过程中,地震动不确定性对套管破坏概率的影响远大于材料离散性对破坏概率的影响。从结果而言,仅考虑地震动不确定性的地震易损性分析结果已经可以满足工程应用需求。

For accurately assessing the influence of material uncertainty on seismic vulnerability of electrical equip⁃ment,one porcelain bushing of a type of ultra⁃high⁃voltage(UHV)gas insulated switchgear(GIS)is taken as an exam⁃ple,the finite element model of the bushing,which is verified by the shaking table test,is set up.The random vari⁃able of material parameters is sampled while considering the seismic motion uncertainty and the seismic vulnerabili⁃ty analysis is performed.The seismic vulnerability of porcelain bushing of UHV GIS is compared before and after con⁃sidering the material uncertainty to explore the influence of material uncertainty on seismic performance and seismic vulnerability of electrical equipment.The results show that the seismic vulnerability of UHV GIS bushing is changed slightly after introducing the material uncertainty,and its dispersion degree is increased.During the seismic vulnera⁃bility analysis,the effect of seismic motion uncertainty on the damage probability of the bushing is much larger than the effect of material dispersion on the damage probability.In terms of the results,the seismic vulnerability analysis result only considering seismic motion uncertainty can already meet the requirements of engineering applications.