Light Weight Rigid Ocs In Elevated Section Of Delhi Mrts

Delhi Metro is the first Metro in the world to provide 25 kV AC Rigid Overhead Conductor System (ROCS) in underground Tunnel. Most of the metros worldwide runs on 1500 V DC. The Elevated section of Delhi Metro is also provided with 25 kV AC Flexible OHE systems. The system is designed in accordance with EN-50119, 50122.MRTS system plays an important role in functioning of the city transport. In the national capital of India, the Delhi Metro has become lifeline of Delhi since it's inauguration in December 2002. Even occasional disruption of services, not only creates inconvenience & chaos between commuters but also invites severe criticism from public & media.A number of failures in flexible OHE have caused disruption of metro services in the past few years. In elevated & at grade sections, DMRC is using conventional 25 kV AC flexible OHE where contact wire is suspended from a stranded messenger wire. Detailed analysis of the failure incidents indicated that catenaries' parting and strands breakages due to short circuit contribute a significant portion i.e. 49% of total flexible OHE failures, While ROCS in underground stations is giving almost trouble-free services. Exploration of the possibilities of adopting Rigid OCS in elevated section shall help in reducing the breakdowns in 25kV traction as this will eliminate the component (i.e. Messenger wire) which is responsible for major failure. Also, mechanical properties of ROCS during electrical faults are far superior to that of flexible OHE.