The Equivalent Circuit and Influencing Factors of Subway Rail Fastener Track-to-earth Resistance

Subway rail insulating fastener is used to isolate the rail and ground. Searches were done of the equivalent circuit of the insulating fastener and influence factors in the track-to-earth resistance. In this paper, with the example of an elastic bar type III fastener, an equivalent circuit of the fastener track-to-earth resistance is given which based on the leakage current path from the rail to the ground. The influence of electrical conductivity and surface conductivity on the transition resistance is calculated. Finally, the conclusion of the research is verified by experiments. The research results in this paper provide theoretical support for further improving the transition resistance of track-to ground.