Advanced modular EP brake control

摘要

The drive towards increased reliability and reduced costs in the railway industry is facilitating the introduction of innovative solutions in safety critical systems such as the brake system. This paper describes the development of a new modular brake control system. The principle development is the move from discrete pneumatic and electrical components to integrated Line Replaceable Units which are being realised as a family of cost effective and reliable compact functional control modules. The modules are locally fitted with intelligence through integrated microprocessors and apply mass produced components from the aerospace and automotive industry. Electrical interfaces and cable trees are minimized through the application of industrial bus communications technology. The functional control modules allow flexible application to a wide range of vehicle types. The customer tailoring of the modules is made in the software rather than the hardware. Maintenance and trouble-shooting is simplified through the optimized LRU structure thus increasing availability of the complete vehicle. The comparison of requirements in the Union internationale des Chemins de fer (UIC) and Association of American Railroads (AAR) was carried out to determine the optimal functional system requirements and a practical realisation of the line replaceable units. The range of brake functions required for a UIC Brake System (exemplified by a Deutsche Bahn AG or SNCF Locomotive) and a North American AAR Locomotive are contrasted and conclusions drawn about synergies. (Reliability issues are addressed by means of reliability block diagrams and mission requirements). Two products, the Computer Controlled Brake System Generation II (CCBII) developed for the North American (AAR) Locomotive market and the Modular Brake System (MBS) developed for the UIC domain are used as concrete examples. These systems make clear the merits of the application of the new system architecture with functional modules.