Near-Field Ground Motion Control Study Of The Role Of Big Substation Isolation

As a transform in power system voltage in substation, distributing electricityexchange of important places, once the earthquake damage suffered, the entire powersystem will face paralysis, causing huge losses to the production and living of thepeople. In recent years, a number of strong earthquakes have caused serious damage tothe substation at home and abroad. It can be found from the distribution of thesedisasters that earthquake ground motion in near-field regions to substations causedmuch more damage than other regions. Base-isolated structure in the far-field groundmotions isolation results are obvious, but the isolation effect remains to be studied in thenear-field region. Therefore, research substation of base-isolated structures subjected tonear-field ground motion and seismic response and potential adverse effects are verynecessary.This is the first in-depth study on the seismic response of large substation isolationstructure in the near-field ground motions and far-field ground motions, the main tasksare as follows:Selected voltage of110kV and220kV substation from the State Grid Corporationof the typical design of power transmission project, which main structure with frameunit and simulation of shell elements, electrical equipment using solid elementsimulation, seismic isolation bearings with rubber shock unit simulation. using finiteelement analysis software to establish two three-dimensional dynamic analysis modelsfor substation isolation structure, In order to test the isolation of substations and theirelectrical equipments, the paper also established these two different voltage levelscorresponding seismic structure of three dimensional dynamic model for substation andthen compare them. Select the1999Taiwan Chi-Chi earthquake (M7.2class) of four commonly usednear-field records and a far-field record as seismic input. Use time history analysismethod to study the seismic response of near-field ground motion under the action ofseismic-isolation structural and response of their electrical equipment. Which areSupported by structural maximum displacement angle, the maximum horizontalacceleration, maximum horizontal displacement and electrical equipment, maximumhorizontal acceleration, maximum bottom shear. The results showed that: Isolationmeasures can effective reduced substation structure of earthquake reaction undernear-field ground motion. Isolation effect of substation isolation structures and theirelectrical equipments are better under near-field ground motions then under far-fieldground motions. PGV(peak ground speed) of near-fault ground motion/PGA (peakground acceleration) the smaller the better the isolation effect of seismic isolationstructure for substations; When the fault margins and PGV/PGA are large, seismicresponse of isolated structure of transformer substation electrical equipment are large.