考虑地震和材料强度不确定性的瓷柱型电气设备易损性分析

Fragility Analysis of Porcelain Cylindrical Electrical Equipment Considering Material Strength and Seismic Uncertainties

瓷柱型电气设备的损坏是地震中电力供应中断的重要原因。准确评估瓷柱型电气设备的抗震能力是评估电力系统抗震能力的重要基础。在历次强震中,瓷柱型电气设备表现较差,即使满足抗震规范要求的瓷柱型电气设备,仍然有相当部分发生了破坏,地震动的不确定性及陶瓷绝缘子材料强度的离散性是造成这一现象的重要原因。为了更准确地衡量瓷柱型电气设备的抗震性能,该文同时考虑地震动的不确定性和绝缘子强度的离散性,采用基于概率的易损性分析方法,以某型隔离开关为例,进行设备的地震易损性分析,考虑闸刀开闭、地震动类型、绝缘子强度离散程度和不同拟合函数等因素对设备地震易损性的影响。与传统的确定性方法相比,基于概率的设备易损性结果可以更准确地描述瓷柱型电气设备的抗震性能。

The failure of porcelain cylindrical electrical equipment(PCEE)is the primary reason for power outages during earthquakes.Precise assessment of PCEE seismic performance is essential to power system seismic assessment.However,it has been found that even seismic code satisfied PCEEs damage during strong earthquakes.The uncertainties of ground motions and material strength deviation are the two main reasons for this phenomenon.To better evaluate the PCEE seismic performance,the probabilistic fragility method was used.A typical disconnect switch(DS)was taken as an example,uncertainties of ground motions and material strength were considered.The influences of ground motion types,switch open/close phases,fitting functions,and material strength deviation degrees were analyzed.Compared with the traditional deterministic seismic performance assessment method,the probabilistic fragility method can better describe the PCEE seismic performance.