The Research And Implementation Of WTB Based On IEC61375-1 Standard

With the development of the technology of embedded micro control and field bus,the process control of modern train has developed from concentrated direct digital control system to distributed control system which based on network.Train Communication Network(TCN), established respectively by International Electrotechnical Commission(IEC),is aiming to offer the convenience to the railway departments and train equipment providers to actualize the interlinkage of train vehicles around the world.TCN comprises two levels,the Wire Train Bus(WTB) connecting the vehicles and the Multifunction Vehicle Bus(MVB) connecting the equipment aboard a vehicle or group of vehicles.Nowadays,the communication system within a train is a central issue for train system integration.WTB can fulfill the requirement of real-time control,diagnosis,and passenger information on-board train.Datas which are transmitted by WTB are divided into real-time process data,non-real-time data,as well as monitoring data.Its most unique feature is infiguaration through the course of the WTB can be automatically connected to the distribution node addresses,available to get all nodes on the bus and the topology information of other nodes.What's more important is,it can be applied in the situation that vehicles maybe coupled or uncoupled frequently in daily operation.Although complete physical and link layer are defined in WTB specification,link layer does the main job.As a result,on the basis of the IEC613275-1 Standard,this paper studies on WTB physical layer,and the message frame,link layer control and interface,infiguaration, and other technical features.This paper designes WTB communications software stack,which is divided into two modules:one is the core process module which is order to realize the core functions of WTB,the other one is hardware interface module which is designed for adapting to a wide range of communications WTBC controller.Finally,in the laboratory we simulate a WTB bus which connectes three nodes,the software has been tested,the basic functions of the WTB communications stack has been achieved.