GIL管廊结构参数对接地系统电气特性参数的影响

类似于输电线路接地系统,气体绝缘金属封闭输电线路(gas insulated transmission line,GIL)的接地系统对该输电方式的稳定可靠运行至关重要。针对GIL综合管廊接地系统进行研究,首先建立GIL综合管廊接地系统模型,对接地系统的接地电阻、跨步电压、接触电压以及地电位升等电气特性参量进行计算分析,然后研究混凝土结构钢筋、终端接地网布置均匀度、铜排接地干线跨接距离以及主结构钢筋与铜排接地干线跨接距离等敏感结构因素对接地系统电气特性参量的影响,获取敏感因素对接地系统的影响规律,从而得出GIL接地系统设计阶段需优先考虑混凝土结构钢筋与铜排接地干线相连作为自然接地体,铜排接地干线跨接距离相对之下是影响最小的因素。从电气模型角度提出合理的接地系统设计,为GIL综合管廊的建设和运维提供了基础。

Influence of GIL Tube Structure Parameters on Electrical Characteristics of Grounding System

Similar to transmission line grounding system, grounding system for GIL transmission also plays an important role in stable and reliable operation. In this paper, the grounding system of GIL is studied. Firstly, a grounding system model of GIL is established, and earthing resistance, step voltage, touch voltage and earth potential rise are calculated and analyzed in this model. And then, some influencing factors of GIL grounding system are studied, such as concrete structure reinforcement, the uniformity and un-uniformity layout of terminal grounding grid, the cross connection distance of tinned copper, and the cross connection distance of the main structure steel connecting tinned copper. Finally, the influence rules of sensitive factors impacting grounding system are obtained. In design stage of GIL grounding system, it is necessary to give priority to connecting concrete structural reinforcement and copper line of grounding as natural grounding body, and the connection distance of grounded copper bars is the least influencing factor. The reasonable design parameters of grounding system from the perspective of electrical model are suggested, providing basis for construction and operation of integrated GIL corridor.