Online method for surface dust removal in GIS/GIL based on gas flow

The insulation fault caused by metal particles adhered to insulator surface is a major factor threatening the safe operation of GIS/GIL. Based on that, an online method of surface dust removal based on gas flow is proposed. That is, the inlet and outlet are set near the insulator respectively, and the pressure difference between gas compressor and chamber will generate gas flow, so as the resuspension of metal particles. This study shows that metal particles are mainly concentrated near the high-voltage electrode and dispersed on inclined plane of insulator under DC stress. Besides, the position of inlet/outlet has a great influence on the distribution of flow field and dust removal effect. When the inlet/outlet are located near the grading ring and slightly offset downward, the dust removal effect is the best. The method proposed in this paper can not only restrain the continuous deterioration of insulation performance by metal particles, but also avoid the cost power-off maintenance, which has the potential of engineering application.