Diagnosis of Partial Discharge Based on the Air Components for the 10 kV Air-Insulated Switchgear

Abstract

Partial discharge (PD) is a common phenomenon of insulation aging in air-insulated switchgear and will change the gas composition in the equipment. However, it is still a challenge to diagnose and identify the defect types of PD. This paper conducts enclosed experiments based on gas sensors to obtain the concentration data of the characteristic gases CO, NO2, and O3 under four typical defects. The random forest algorithm with grid search optimization is used for fault identification to explore a method of identifying defect types through gas concentration. The results show that the gases concentration variations do have statistical characteristics, and the RF algorithm can achieve high accuracy in prediction. The combination of a sensor and a machine learning algorithm provides the gas component analysis method a way to diagnose PD in an air-insulated switchgear.

Adsorption of a MoSe2-Based Sensor for Fluorocarbon Gas Decomposition Products in Gas-Insulated Switchgear: A First Principles Analysis

“…When the power system fails, the interconnected equipment can be stopped through an isolating switch, which protects the connected power equipment and the safety of power operators. In the process of manufacturing, distribution, installation, operation, and maintenance of the switch cabinet, various insulation defects will inevitably occur in the cabinet, such as metal burrs left on the surface of the conductor during manufacturing, loosening or poor contact performance of the parts during transportation, and residual metal particles in the cavity after maintenance. − These insulation defects are easy to cause electric field distortion during the operation of the switchgear, resulting in partial discharge and even arc. , Timely detection of insulation inside the switchgear is important to avoid huge economic losses and negative social impacts caused by safety accidents due to insulation damage in the cabinet. Many scholars have studied the discharge decomposition of SF 6 in GIS and judged the partial discharge of the equipment by analyzing the concentration, discharge volume, and gas production of the decomposed components .…”

“…4−6 These insulation defects are easy to cause electric field distortion during the operation of the switchgear, resulting in partial discharge and even arc. 7,8 Timely detection of insulation inside the switchgear is important to avoid huge economic losses and negative social impacts caused by safety accidents due to insulation damage in the cabinet. Many scholars have studied the discharge decomposition of SF 6 in GIS and judged the partial discharge of the equipment by analyzing the concentration, discharge volume, and gas production of the decomposed components.…”

Study on characteristics gases of metal protrusions partial discharge in 10‐kV air‐insulated switchgear

“…They initially explored the practicability of gas component analysis in PD monitoring of switchgear, but did not study from the view of fault identification. Then, the generation rates and the stability of products in air discharge have been studied based on the density functional theory and the transition state theory, confirming that choosing CO, O 3 and NO 2 as characteristic gases could reach defect‐type identification [14, 15].…”