Tunnel overhead contact wires are all flexible suspended contacts. According to the query related information, the flexible suspension electrical segmentation generally adopts the segmented insulator method and the anchor segment joint form. The segmented insulator method is suitable for underground tunnels and can save space, but it must be equipped with a dedicated There are segmented insulators, and when the train pantograph slides across the segment, there are stress-bearing hard points at the connection between the conductor and the segmented insulator, which can easily cause the pantograph to go offline and cause obvious arcing. There are roughly three types of suspension for simple suspension overhead contact lines: simple suspension, chain suspension, and rigid suspension. Among them, simple suspension and chain suspension are both flexible suspensions, and the corresponding catenary is also called flexible catenary and rigid catenary according to the suspension type.