Optical Mie Scattering Concentration-Dynamics Tracer Joint Detection Method for Micron-Nano Dust in GIS/GIL Systems

Advanced transmission equipment gas-insulated switchgear (GIS)/gas-insulated transmission line (GIL) is an important part of new energy power system, and metal dust is inevitably generated during its production and operation, which may be the cause of inducing unknown discharge in engineering site. Based on the principle of light scattering, an optical Mie scattering concentration-dynamic tracer detection platform for GIS/GIL for metal micron-nano dust is established in this article, and the calculation method of dispersion coefficient is proposed. Through the simulation analysis of dust scattering characteristics, the optimal receiving angle of scattering light of 60° is selected, and the detection error of the system is verified to be less than 5%. The results show that the dust dispersion concentration is affected by many factors, such as the properties of applied electric field, the characteristics of dust itself and the initial positions, and the change of dust concentration reveals the characteristics of air gap breakdown induced by dust properties and its influence on the breakdown voltage. At the same time, the agglomeration and dispersion phenomenon of micron-nano dust is observed by the optical tracer system, and the concentration influence mechanism of the breakdown process is further studied. This study provides theoretical basis and technical support for the improvement of micron-nano dust monitoring technology and the improvement of GIS/GIL insulation operation safety and lays a foundation for the in-depth study of micron-nano dust movement characteristics and risk assessment.