悬吊式滤波电容器单体与耦联状态抗震性能对比分析

高烈度抗震设防地区的换流站中悬吊式滤波电容器耦联状态下的抗震性能对特高压直流换流站正常运行有重要意义。本文以某特高压悬吊式直流滤波器耦联回路为原型,建立悬吊式滤波电容器单体状态和耦联状态的有限元模型并在此进行了地震响应分析。结果表明相比于单体状态,耦联状态下悬吊式滤波电容器各层三向加速度峰值最大值均有减少,内力响应最大值略微提高,各层最大位移偏移图呈现月牙状且耦联体系平面内变化最大。支柱类电气设备对悬吊滤波电容器耦联平面内的侧向刚度有一定的强化,同时耦联状态中悬吊滤波电容器的加速度响应受到1 Hz以下低频波作用更加强烈。支柱类电气设备对电容器水平双向位移响应的放大作用并不剧烈,可不用关注耦联后水平位移响应改变导致的设备间距调整的问题。支柱类电气设备耦联作用对电容器弹性回跳现象的发生起到抑制作用,但导致外侧斜向悬吊绝缘子内力响应剧烈增加,需要提高外侧斜向悬吊绝缘子V型交汇处连接金具的强度。

Comparative Analyses on Seismic Performance of Suspended Capacitor in Standalone and Coupled States

Seismic performance of the coupled suspended filter capacitor in high intensity seismic fortification region is significant for UHVDC converter substations.Based on a suspended UHVDC filter coupling loop,the finite element models in the standalone and coupled states were established and seismic responses of the two modes were investigated.The results indicated that,the maximum value of the three-direction acceleration peak of each layer of the suspended filter capacitor is reduced in the coupled states,compared with that of the standalone,and the maximum internal force response was slightly increased.The diagram of the peak displacement of the layers presented as the crescent shape and changed seriously in the coupled plane.The post electrical equipment could increase the lateral stiffness in the coupling plane of the suspended filter capacitor and the acceleration response is more likely to be affected by the low frequency components,which are below 1 Hz.The amplification effects of the post electrical equipment on the horizontal displacement responses of the filter could be ignored,which means that the distance between different equipment do not need to be changed after considering the interconnecting effects.The coupling effect of the post electrical equipment suppresses the occurrence of elastic rebound while increases the internal force response of the outer oblique insulators rapidly.Moreover,it is necessary to improve the strength of the fittings of the V-shaped intersection of the outer oblique insulators.