Heavy Haul Trains Locomotive Brake Developed

Domestic DC transmission electric locomotives adopt DK-1 type locomotive brake system at large, because this kind of locomotive brake does not possess the functions of microcomputer control and network communication, so it can not realize the closed-loop control to balanced air cylinder pressure, can not meet the demands of the heavy combined trains'wireless synchronized control.Based on the existing locomotive brake technology, the paper analyses present situation of foreign heavy combined trains'locomotive brake,develops a new locomotive brake with the functions of microcomputer control and network communication, so as to fit locomotives'wireless synchronized control system, to meet the requirements of the use of heavy combined trains.Locomotive Brake must meet the basic functions of brake,such as trains'automatical brake,locomotives'individual brake,the combination of air brake and electric brake(air-electric combined brake),protection of coupler failure, sufficient air flow testing on locomotives,brake reconnection, trains'electric-air brake,monitoring reordination of trains' speed, at the same time, it must be compatible with some operations' requirements,such as the current domestic railway locomotives' stand-alone operation, trains'control,reconnection operation and traction connection and other operations'requirements.based on the analysis of the fact that locomotive brake must meet UIC,AAR,TB and other standards in this industry, the paper proposes the design of heavy combined trains'locomotive brake.Compared with traditional DK-ltype brake, this program adopts microcomputer control technology, realizes accurate closed-loop control to balanced air cylinder and achieves the reconnection control of locomotives'remote brake through locomotive network, and it possesses stand-alone self-test, fault diagnosis,data storage and other informationization functions,so that it can adapt to the development requirements of the informationization and network control of a modern locomotive brake. Based on the technology of DK-1 brake, this project adopts foreign advanced technologies and concepts to do the engineering design and components selection on the heavy combined trains'locomotive brake.In the choice of valves it inherits the technologies of DK-1 brake, and upgrades in technics.The new key components, such as high speed electro-pneumatic valves and pressure sensors, not only need to meet the requirements of the pressure closed-loop control accuracy, but also need to adapt to the special environmental requirements for locomotives.In order to increase the reliability, maintainability, modularity, and standardization of the brake's air pipe connection, facilitate the arrangement of the various components of the air-brake cabinet and make a more beautiful appearance, this thesis adopts an integrated gas-circuit-board as piping integration approach of the air piping system. In the selection of the key diameter pipe in the system, parameter matching of the sufficient air flow of the brake and the whole train's brake will be taken into the main consideration.Brake control unit is the core control device of the brake.It adopts intelligent, modular, integrated designing idea to design the brake control unit.In order to meet the requirements of the system's real-time,and scalability, it uses PC/104 structure as the brake control unit hardware platform; it uses QNX real-time operating system and ISaGraf as a software development platform so that it enables the realization of graphical programming structure and possesses the capacities of online downloading and debugging; it uses CAN or MVB networks to achieve remote network control of the combined trains.This paper gives out the control logic of the brake in a variety of mode,fault diagnosis methods and the communication protocol of network control,using fuzzy adaptive PID control method to do the balanced wind-cylinder pressure control on pressure control,experimental datas show that the control method can meet the requirements of errors and control speed.The properties of new-fashioned locomotive can meet the design requirements or not, a single machine test and tons of traction test under a stationary state are conducted on the brake.The analysis of the experimental datas of these two experiments show that the locomotive brake fully meets the needs of heavy combined trains.The current project has been completed the identification by the Science and Technology Department in Hunan Province and CSR.