A Study on the Switching Surge Characteristics of Grounding System in the Main Substations of Rapid Transit Systems

• Main Authors: Yu-Lun Huang, 黃鈺倫
• Other Authors: Chih-Ju Chou
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/45070653188961413630

碩士 === 中原大學 === 電機工程研究所 === 90 === In the thesis, the switching surge characteristics of grounding system in the main substations of Rapid Transit System (RTS) are analyzed. The switching surge characteristics to be analyzed include the transient ground-potential-rises (GPR’s) and the ground-potential-differences (GPD’s) between various ground points on grounding system, and the electromagnetic fields and step and touch voltages on the ground surface due to the switching to close in the gas-insulated-substation (GIS) of RTS. The grounding system comprises of multiple ground grids and the ground wires distributed from the ground grids to the ground buses of GIS. The conditions to be considered for the analysis of switching surge characteristics include the states of connection or separation between various ground grids, the ground wires distributions, the operation modes of switching to close and the situations of energizing the bus of GIS and the main transformer. The issues of personnel and equipments safeties affected by the switching surges are assessed. The analysis results have shown that the transient GPR and GPD on the ground buses may threaten the equipment safety. Especially, the ground wires are dangerous if their routes are along with the steel rebars of building or inner steel pipes or with long distances. The improvement measures for enhancing the equipment protecting against transient GPR and GPD and the measures for improving personnel safety are also presented in the thesis.