Detection and Analysis of Ultraviolet Corona Discharge for Earth Switch Grading Ring

The appearance of corona discharge means that the equipment may have defects in insulation. The application of ultraviolet(UV) imaging detection technology can timely find hidden dangers of equipment, evaluate the insulation status of operating equipment, and effectively improve the reliability of power supply. This paper combined with the finite element simulation analyzes the electric field on the surface of earth switch grading ring in a 500kV substation and the simulation results are consistent with the results of ultraviolet detection. Then the effects of operating voltage and relative humidity on the ultraviolet detection results are studied, which provides a reliable basis for the application of ultraviolet detection technology in actual field.