Research on Algorithm of train physical topology generation based on Ethernet

Whether the train physical topology is established or not is the key to the normal operation of the train, and the generation algorithm of the train physical topology is the core of the train network control technology. Based on IEC613752-5 protocol, this paper implements the algorithm of train physical topology generation. This algorithm is suitable for train coupling and uncoupling conditions, and can well detect the marshalling network equipment and network connection during the lengthening and shortening process of high-speed trains. The rationality of the algorithm is tested by substituting the algorithm into the reconnection process of three marshalling trains. The experimental platform of 100 MB Ethernet is built, and the algorithm running results are compared with the normal running results of the Ethernet platform. The results show that during the marshalling and unmarshalling process of high-speed trains, the initial train operation process will be triggered, and the physical topology of the train connection table can be calculated through the train physical topology generation algorithm in the initial run process. The physical topology generation algorithm can realize the composition and monitoring of the entire train network topology based on the HELLO data frame and the TOPOLOGY data frame. When the train marshalling structure changes, the physical topology generation algorithm will recalculate the physical topology according to the real-time train marshalling structure, so that users can monitor the train physical topology in real time and ensure the safety of train operation.