The Design And Realization Of MVB Controller Supporting Redundant Mediums

With the large scale operations of electric multiple units and high-speed rail, and the introduction of electric locomotives, the application of train communication network has been much wider. TCN consists of the secondary subnets which are composed of Wire Train Bus and Multifunction Vehicle Bus. MVB is vehicle bus, and due to the complexity of the locomotive internal environment, it needs two redundant buses to transmit data for accuracy. The design of MVB network card which is composed of MVB controller and manager has the biggest difficulty in MVB products. Because domestic TCN tends to technology introduction and application development, not enough work has been done in aspect of key technology breakthroughs.there are only a few rail transport enterprises and universities research MVB devices such as MVB controller, there are fewer research the MVB controller supporting redundant mediums. Therefore, researching on the MVB controller supporting redundant mediums has important significance for the autonomy of TCN technology.On the basis of the analysis and deep research on the TCN international standard IEC61375-l,the overall design scheme of MVB controller supporting redundant mediums is put forward. The selection of physical redundant mediums and the data transmitting /receiving on data link layer are the basic functions of the MVB controller supporting redundant mediums. The controller is divided into three parts according to the function and designed in the top-down method. The first part is transmit module of MVB controller whose main function is the encapsulation and transmit of frame, including frame data encoding, CRC sequence generation and so on; The second part is receive module of MVB controller whose main function is frame receiving and unpack, including frame data decoding and data verification and so on; The third part is line redundancy control module of MVB controller whose main function is line switchover and the selection of trust line, including the report of line redundancy state and generation of line switchover signal and so on.FPGA is adopted to complete the design of MVB controller. All simulations of functions are accomplished and the design meets the requirements of the international standard IEC61375-1.On this basis,the design of core system circuit principle diagram and PCB layout of MVB controller and board-level validation of part functions are completed.