Detection and analysis of high voltage electrical equipment corona discharge based on ultraviolet imaging technology

The corona discharge phenomena of electrical equipment are generated with the increasing of insulation aging, electrical equipment, surface filth or atmospheric humidity. The corona discharge will cause the waste of power energy, radio interference, audible noise, insulation aging, and these defects are great threats to the safety and stability of electrical equipment. Using appropriate method to detect the operational state of electrical equipment is always significantly concerned by operation department. In this paper, the different corona discharge defect part of high voltage electrical equipment are summarized such as the grading ring, drop wire, jumper and over line, spacing rods, tube bus end and connecting joint. While the photon numbers of corona discharge under different defects are measured by the ultraviolet imager. The result shows that: the corona discharge characteristics of electrical equipment are different under the different defect type, and the photon number increases with the rising of the applied voltage. The detected photon number varies with different kinds of defects through applying same voltage. The ultraviolet imager shows the excellent performance in the detection of discharge defects and thus it can be prospectively used in the operation state detection of electrical equipment.