Sensitivity Analysis of Breakdown Voltage for Defects in GIS: A Reexamination on Impulse Wavefront Times

Authors：Wen, Tao^*; Huang, Yulong; Chang, Jiuqian; Zhao, Yi; Tan, Xiangyu

Source：IEEE Transactions on Dielectrics and Electrical Insulation, 2023, 30(1): 353-358.

DOI：10.1109/TDEI.2022.3220480

• Gas-insulated metal-enclosed switchgear (GIS)
• impulse test
• sensitivity coefficient
• wavefront time

Lightning impulse (LI) test is an effective means to detect insulation defects in gas-insulated metal-enclosed switchgear (GIS). However, the wavefront time T-f of LI has a great influence on the breakdown charac-teristics of GIS with insulation defects. In this article, the sensitivity analysis of breakdown voltage to T-f was studied. The sensitivity coefficient k(e) was proposed to evaluate the sensitivity of breakdown voltage to T-f for different insulation defects. The results showed that the nonuniformity of electric field is the key factor that affects the sensitivity coefficient k(e). The influence of T-f becomes more significant with the increase of the nonuniformity of electric field. The application of the sensitivity coefficient k(e) to the evaluation of insulation defects detection was implemented, and the results verified that the impulse detecting effectiveness of insulation defects can be obtained quantitatively for defects with different electric field inhomogeneity coefficients.