Research On Railway Dynamic Detection System For Compensation Capacitor Of Track Circuit Based On Integrated Positioning

The compensation capacitor of track circuit is an indispensable component in the electrified railway. It plays an important role in compensating for signal transmission in the jointless track circuit. With speeding up of the existing rail and the rapid construction of high-speed passenger-carrying line, the large number of compensation capacitor laid in a board range of the whole railroad in China, which brings some difficulties to the maintenance and repair. Traditional maintenance model is that used the portable instrumentation to the site, this method is time-consuming and inefficient obviously. However, the inspection railcar used dynamic detection technology will be able to solve this problem. Railway dynamic detection system for compensation capacitor of track circuit not only improves the working efficiency, but also monitors the working status of the compensation capacitor of track circuit, at the same time, it would accomplish the process of the major shift from fault repair to the state repair. Railway dynamic detection technology has become a new trend in the field of railway signal equipment testing at home and abroad.The paper sets forth the function, working theory, structure characteristics, configuration principles of the compensation capacitor, and analyzes the causes of damage and harm to the jointless track circuit. On this basis, this paper opt the sweep measurement to test program, because of its high reliability. Simultaneously, in order to improve the location accuracy, the continuity and real-time of the flaut point, the paper select the integrated positioning program of GPS/DR/MM (global positioning system/dead reckoning/map matching) to provide the positioning informations for dynamic detection system. Also the paper utilizes the adaptive federated Kalman filteing algorithm for multi-sensor information fusion, in order to gain the optimal estimation of the locating data output. And through simulation experiments results further demonstrate that the application of integrated positioning method and adaptive Kalman filter algorithm can get higher precision positioning informations than the single positioning method. Then the data from the positioning subsystem and the compensation capacitor test subsystem can switch through the ethernet. It can use the method of setting the discrimination threshold to judge which compensation capacitor is invalid or lose, and to statistics these results. Finally, we could achieve the fault point positioning.Ultimately the paper builds the development platform based on the embedded system ARM9/Linux, makes the detailed hardware and software design simultaneously. Used the S3C2410’s rich on-chip resource, it could complete the hardware design in GPS module, DR module, network control module, LCD display module, compensation capacitor test modules, processor modules, memory modules and so on. Also it could accomplish the software design in GPS data extraction module, adaptive federal kalman filter algorithm module, map matching algorithm module, compensation capacitor discrimination and statistical module and so on.On the viewpoint of engineering application, the principle of testing was studied on the dynamic detection method for compensation capacitor of track circuit in systemic. In the paper, it makes the framework structure design of hardware and software with the embedded platform. And the results can provide a reference to realize materialization of the protablely hand-held tester for compensation capacitor of track circuit, which is used to railway S&C observation railcar or comprehensive inspection vehicle in Railroad Bureau’s staff of the communication and signaling sector.