Simulation and Analysis of Rail Potential for Diode Grounding System at Rapid Transit System

• Main Authors: Tsung-Chi Hsu, 許琮棋
• Other Authors: 古碧源
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/57hr5h

碩士 === 國立臺北科技大學 === 電機工程系所 === 93 === In this thesis we represent the rail potential performance and analysis method for diode grounding system of the preliminary network of Taipei Mass Rapid Transit. We develop the analysis method of rail potential by diode grounding, and apply it to estimate the stray current effect for diode grounding system to transit system. In the earlier design for railway DC power system, rectifier negative return bus is directly connected to grounding earth on safe consideration. There for, the rail potential of electric railway is identical to system grounding. However, extremely high values of stray current have been measured and seriously affected the building and underground facilities neighboring to railway system as corrosion problem. Reducing the magnitude of stray current by using the diode ground and ungrounded system design is essential solution but the rail potential may be getting higher. According to this phenomenon, diode grounding configuration is the last selection for DC system design criteria of the preliminary network of Taipei MRT. Due to this configuration has been commercial operation among foreign countries. We now emphasize the measurement of rail potential exceeding original design. Therefore, this thesis presents the concept of floating grounding basing DC analysis develops rail potential diode grounding, and using the differential potential method calculates the full rail system accuracy potential. In the result, it shows not only those calculate rail potential for all diode grounding system position and determine the time of drainage diodes turning on but also prove by measurement. This thesis statement makes much accuracy estimation of full rail potential position compare to the international relative research and plenty contribution of the research in drainage diode turning characteristic and stray current.