OCS is erected on the top of the railway. Through the sliding friction between the pantograph on the top of the electric locomotive and the contact wire, the flexible catenary system continuously supplies power to the electric locomotive running on the railway line. It is composed of contact suspension, support device, positioning device, pillar and foundation. The manufacturing process of parts is simple and stable. It has the characteristics of good elasticity, good contact between pantograph and catenary, high current collection quality of contact wire, low cost and high safety. It is suitable for high speed vehicles.