Intermittent Discharge Characteristic of GIS under Suspended Electrode Defects

Compared to traditional power system devices, gas-insulated switchgear offers advantages such as excellent operational stability, a relatively compact internal structure, and reduced space requirements, making it widely used in substations. However, decades of operational experience indicate that unavoidable insulation defects may arise during manufacturing, transportation, installation, maintenance, and operation. To address the frequent issues of missed and false reports in monitoring partial discharge insulation defects in GIS, intermittent discharge has been identified as the root cause. This is because the time intervals between intermittent discharges are significantly longer than those of stable discharges, causing traditional partial discharge detection systems to misinterpret intermittent discharge pulses as interference signals and overlook them. Therefore, this study focuses on the intermittent discharge of floating potential defects in GIS. The results indicate that, as pressurization time increases, the discharge quantity of floating electrode defects initially increases and then decreases over time. With higher temperature levels, the discharge quantity progressively increases. Additionally, as temperature levels rise, the time intervals between intermittent discharges become shorter, leading to a decrease in discharge intermittency