220 kV支持式管型母线结构抗震性能

为了研究管型母线结构在地震中的安全性，以220 kV支持式管型母线结构为研究对象，采用有限元模态分析手段和时程计算方法，研究了结构在不同地震烈度下的振动响应特征，并计算了关键部位的主应力。计算结果表明：220 kV支持式管型母线结构的前10阶自振频率为1~3 Hz，处于地震波的卓越周期内，地震时结构容易出现共振；支柱绝缘子的最大弯矩都出现在底部，断裂破坏也最可能出现在这一部位；当地震荷载的烈度为7度及以下时，支柱绝缘子的最大拉应力小于陶瓷材料的设计极限应力，结构处于安全状态；在烈度为8度及以上的地震荷载作用下，会有部分位置的支柱绝缘子因受力超出材料的极限应力而发生断裂，结构处于危险状态。

Seismic Behavior of Supported Tubular Bus Structure in 220 kV Substation

In order to analyze the security of tubular bus in earthquake, taking the supported tubular bus structure in 220 kV substation as a research object, the vibration response characteristics of the structure under different seismic intensity are studied, and the principal stress at key position is calculated, by using the finite element model and time-history method. The analysis results show that the first ten natural frequencies of supported bus structure are 1～3 Hz, which are in the predominant period of seismic wave and are prone to resonance during earthquake in its structure. The maximum moment of post insulators happens at its bottom, which makes it easily to be broken. If the seismic intensity is less than or equal to 7 degree, the whole structure is safe because the tensile stress of post insulators is less than the ultimate strength of ceramic. However, if the seismic intensity is equal to or greater than 8, there will be fracture with some post insulators due to the exceeded stress, which may make the structure in danger.