Study on the reliability of 10kV uninterrupted maintenance outgoing switchgear under the condition of main device switching to the back-up device

摘要

Very large overcurrent and overvoltage will occur when the disconnectors switching the main device to backup device for live maintenance, which will threaten the reliability of the switchgear. Therefore, a research about the reliability of switchgear under the switching condition is carried out. Based on the analysis of the transient switching process, the overcurrent and overvoltage are obtained. Then, a 3D FEM model to study the insulating properties and temperature rise characteristics of the switchgear are set up respectively, and the electric field and temperature rise are calculated. The results show that: 1) 17.3kV overvoltage and 1.42kA overcurrent are generated during the switching process;2) The maximum field strength and temperature rise can reach 3.65 kV / cm and 65K respectively, which still meet the requirement of switchgear design standard.