The Tcn Line Redundancy Control Unit

Nowadays, it is an inevitable trend that the new generation train is developing toward the aim of high-speed and automation. Train Communication Network (TCN) has become the core component of the control system of high-speed electrical train. And the research on the devices conforming to the international standard of TCN will have a very promising prospect. Combined with National Natural Science Fund Project (60674003), redundancy control technology is exhaustively studied here.According to the standard of IEC61375-1, the architecture of TCN is consists of two levels: Wire Train Bus (WTB) and Multifunction Vehicle Bus (MVB). In order to ensure the high reliability of the system, redundancy theme is adopted. Every Bus has been doubled to avoid the data errors which may happen when data are transmitted through a single line. When one of the lines fails to work, line redundancy technology can ensure the constant data communication. In order to make sure that every device has the ability to recognize the error line and switch to another line for data receiving, a Line Redundancy Control (LRC) unit is studied and designed here to accomplish the right line switchover operation and ensure the high reliability of data transmission.Firstly Configuration of TCN is introduced. Study is made on WTB and MVB communication network. Data error control and all sorts of redundancy technologies of TCN are discussed. Then the overall design plan of LRC unit is given. Four modules of LRC unit such as device line mode selection module, LAT and RLD management module, line switchover control module and error counters management module have been implemented by using hardware description language. Finally a series of simulation tests have been carried on every module, and the correctness and validity of the LRC unit design have been verified upon these simulation results.