155 / 2022-03-14 12:04:37

Surface Charge Dissipation Mechanism on Post Insulators under X-Ray Radiation

surface charges,dissipation,X-ray irradiation,insulator,DC GIL

The surface charge on insulators can be rapidly dissipated by X-rays without opening the GIL (gas insulated transmission line) pipeline. Therefore, the efficiency of operation and maintenance is improved. However, a theoretical explanation is still lacking. In this paper, a surface charge measurement platform is built up. The surface potential distribution before and after X-ray irradiation is measured under the applied voltage. As a result, the dominant pathway for charge dissipation is verified. Besides, a surface charge transport model considering the influence of X-rays is established. The effects of X-rays on surface charges and the insulation of gases are revealed. The results show that the dominant dissipation pathway for surface charges under X-rays is the conduction current in the gas side. X-rays are suitable for surface charge dissipation only when the GIL is offline. Besides, the insulation of the gas can be self-recovered after X-ray irradiation. Therefore, the effect of X-rays on gas ionization should be considered when X-rays are used to dissipate surface charges on GIL insulators.