全封闭组合电器室SF6气体泄漏分布规律与气体检测布置策略

全封闭组合电器(GIS)在运行过程中不免故障,会出现SF6气体泄漏的问题,这不仅会对设备维护人员的人身安全构成极大威胁,也会对环境造成难以估量的负面影响。目前,SF6气体检测及回收装置布置策略缺乏理论指导。针对盆式绝缘子开裂而造成的SF6气体泄漏事故,本文基于FLUENT软件,结合SF6气体泄漏的两相流三维非定常态湍流流动特征,搭建三维传递现象模型,进行真型尺寸GIS站室泄漏SF6气体分布规律仿真研究。分析了GIS设备因故障而发生气体泄漏时,SF6气体扩散的过程及SF6气云的分布规律,比较了不同位置、不同方向出现单点泄漏时SF6气体的扩散分布情况。再结合GIS室实际空间布局,指出应在贴地安全警示带距离地面0.5m处及GIS设备上方沿纵横方向均匀布置SF6气体检测设备,形成立体的空间密集网状检测系统。

Research on the Distribution Law of SF6 Gas Leakage and Gas Monitor Layout Strategy in GIS Substation

During the operation of gas insulated substation (GIS), there will be problems of SF6 gas leakage due to some failures, which will not only pose a great threat to the personal safety of equipment maintenance personnel, but also cause an incalculable negative impact on the environment. At present, the layout strategy of SF6 gas detection and recovery device lacks theoretical guidance. Taking the SF6 gas leakage accident caused by the cracking of basin insulator as an example, based on the FLUENT software, this paper built a three-dimensional transmission phenomenon, and simulated the distribution law of SF6 leaking gas in true-size GIS station. Combined with the three-phase unsteady turbulent flow characteristics of two-phase flow of SF6 gas leakage, the process of SF6 gas diffusion and the distribution of SF6 gas cloud were analyzed when gas leakage occurs due to the faults of GIS equipment. And the distribution of SF6 gas diffusion at single point and leakage in different locations and directions was compared, which provided reference for the location of SF6 gas detection and also the arrangement of recovery device. In combination with the actual situation of the GIS station, the SF6 gas detection equipment should be installed at a grounding safety warning zone 0.5m from the ground and evenly arranged in the vertical and horizontal directions above the GIS equipment to form a three-dimensional spatial dense mesh monitoring system.