Electric Locomotive Electrical System Fault Diagnosis Expert System Research And Design

Electric locomotive is an important means of delivery in China, to ensure its safety is essential. Electrical system is an important part of electric locomotives, if the electrical system is not working well, the normal operation of electric locomotives will not be ensured. In order to ensure the trains running safely and punctually, and meet the people's basic needs, the electrical faulty of locomotive should be diagnosed quickly and be positioned precisely. Currently, electric locomotive in China with fault diagnosis function is limited. Therefore, it plays an important role to study electric locomotive electrical system fault diagnosis technology.Firstly, the development status of fault diagnosis technology for electric locomotive in the domestic and international is briefly reviewed in this paper, and the development trends of locomotive fault diagnosis is predicted. Secondly, the similarities and differences between the classic expert system and fault diagnosis expert system are analyzed, and the advantages and disadvantages of the common fault diagnosis expert system are compared. This paper chose the fault diagnosis expert system based on fault tree for electric locomotive electrical system diagnosis. Then this article focuses on how to build a fault tree-based fault diagnosis expert system, its main contents include:establishment of the fault tree for SS8 electric locomotive, the knowledge-based acquisition from fault tree, knowledge representation, the storage of knowledge and fault tree based on ACCESS database technology. The inference module is designed to take advantage of the positive control of reasoning and heuristic search strategies, and introduces the concept of rules importance to achieve the matching rules orderly. The most of corresponding fault trees about electrical system fault are summed up based on the main-depth research and analysis of the SS8 electric locomotive by the control circuit, traction transformers, converters and others, or exchange of experts in the field. Finally, based on the analysis above, the fault diagnosis expert system for electric locomotive is described which is developed by making use of Visual Studio 2005 development platform, the software successfully achieved the separation of knowledge base and inference engine, automatic acquisition of rules from the fault tree functions and so on. The using of the system is simple, and experiment debugging shows that the system has high reasoning efficiency, stability and reliability.The results of this paper are shown as follows:(1) Most of the fault trees SS8 electric locomotive is built; (2) Fault diagnosis expert system based on fault tree for electric locomotive is designed, and the concept of importance the rule is introduced; (3) Fault diagnosis expert system software for electric locomotive is developed.