New Measurment For Detecting Arcs Due To The Pantograph Contact Loss Form The Contact Line In Electric Railways

To detect the occurrence of arcing between the pantograph and the overhead contact line, a new measurement system is studied and set up. The system uses phototube to measure the duration of the ultraviolet emission due to the electric arcing. The major advantages of the system proposed are its non-invasivity with the pantograph equipment, its reliability and its low cost.Firstly, electrization knowledge related to the research is introduced. After a deep study on various contact loss detection techniques, especially on the electric arcs detection techniques, we draw the conclusion that the untouched detection technique based on phototube sensor can acquire exact contact loss information, and will to be the leading technique for contact loss measurement in future. Secondly, combining with the special railways system in our country, we analyze the cause of the arcs, and the influence on the power supply system and the on board traction drive due to the arcs in detail, and study the arcs' spectrum characteristic. We also analyze detecting principles and put forward with a method - using phototube sensor to detect the contact loss arcs, conceive the configurations and detection flows of the measurement. Then, hardware and software designs of the measurement is detailedly explained, including phototube sensor's selection and characteristic parameter calculation, hardware circuit design, communication system design and so on. Finally, this paper introduces the measurement running status in laboratory, detailedly analyzes the measuring data, and summarizes problems encountered in the experiment. At last, this paper summarizes the significant designs during the course of research and development, and prospects that powerful automatic detection measurement will be developed for contact loss detection in future.