Investigation on Flashover Performance of 25 kV Traction System Section Insulator Assembly in DMRCL System

This paper describes the failure analysis of a section insulator assembly at one of the depot of Delhi Metro Rail Corporation Limited (DMRCL). Frequent breaker tripping at Saritavihar depot of DMRCL due to flashover of the section insulator assembly was observed; the cause of failure of the section insulator was investigated and presented in this paper. As a first step laboratory tests on new and used section insulator assemblies were conducted to make comparative analysis, and then simulation studies were carried out to estimate the possible over voltages during different switching operations and their relationship with the test voltages used in the experimental investigation. This paper presents the laboratory experiments and simulation studies for the failure analysis of section insulator assembly of DMRCL.