The Application Of CAN-BUS And J1939 In FuelCell-Electric Bus

In order to solve the problem between various controllers of electric bus to exchange information, according to the origin and development of CAN-bus, it is the best choice without doubt. Compared with general communication bus, the communication of CAN-bus is security, real-time and flexible.The paper with fuel-cell electric bus for application platform, correspondence standard conform to CAN2.0B and J1939 protocol, according to the complicated computer control structure and actual condition of fuel-cell electric bus, designed a whole communication system comparatively.The important work and characteristic of CAN as the mainstream field bus has been analyzed in the article, discussed the enormous potentiality and development prospect on the fuel-cell electric bus of CAN. Contrapose the communication mechanism of the bus system for electric bus, bring forward an effective project for arbitration. Meanwhile, analyzed the basic principle and enactment method of bit timing in detail, calculated the delay time in transmission of CAN-bus.Anatomized the basic format and communication principle of J1939 deeply, through the compare with CAN, the important action in application layer is brought into prominence; after analyzed the communication units of electric bus, combined the protocol of J1939, a particular application protocol of electric bus among the communication nodes has been constituted.Has carried on the distinct analysis to the actual operating mode request of electric bus, proposed the complete frame of CAN-bus communication system on electric bus, meanwhile, analyzed the functions of main modules, designed a double-circuit redundancy net structure based on optical fiber, and put up the material realizing project.Studied the four kinds of main topology structure of CAN-bus, through analyzing the agreement standard of CAN, defined the agreement rule of optical fiber communication on the electric bus, and designed a node of CAN-bus which was applicable for electric bus, meanwhile, carried on the corresponding software design. At last, put forward an improved project based on DSP TMS320F2812 of TI, and expatiated the detail profoundly. In the end, feasibility experiment contraposed the communication system of electric bus has been carried on, and a perfect result was gained, the experiment proves the feasibility and validity. This plan in such aspects as the field bus control of electric bus, information transmission, and so on, has the application value extremely.