Research On Railway Power Supply System Reliability

With the rapid development of railway industry, the reliability of railway power system becomes more and more important. Traditional railway power system reliability assessment focuses on calculation of long-term statistical reliability index. It is lack of practical significance to emergency early warning and rapid processing of system failure. In recent years, both at home and abroad researches on the operational reliability assessment of large-scale interconnected power system develop quickly. Operational reliability assessment aims at power system short-term, and even ultra short-term (real-time) reliability assessment and prediction. It has great practical value. At present, for the study of railway power system reliability mainly stays on the traditional reliability evaluation methods, rarely on its operational reliability evaluation. As the national railway lines overall connect currently, therefore, it is necessary to research the operational reliability assessment of railway power system in-depth, to realize railway power system short-term reliability evaluation.Failure of Railway power equipment is influenced by the external environment and its own characteristics. Only using the statistical average of the equipment failure rate cannot satisfy the requirement of reliability evaluation. In this paper, on the basis of operational reliability theory, through analyzing the operational features of railway power equipment, failure rate models of transformer, railway power line, and other power equipment are established. Furthermore, equipment failure probability models are established based on the Markov theory, used for overall system short term reliability evaluation. Then, through analyzing the influences of special power supply mode and load characteristics in railway power systems on its short-term reliability assessment, the specific operation process of the reliability evaluation is given. railway power system reliability assessment software is designed by using B/S structure and Java web technology for. Internet browser is its client. Its operation is simple and convenient for relevant personnel. Finally, a specific reliability evaluation example is given by using the evaluation software. Then the impact of various factors, power supply mode and transmission line on the system status and reliability index of railway power system short-term reliability evaluation is quantitatively analyzed.