Abstract：Setting and calculation of protection for line, protection for transformer and protection for busbar in 35kV power system of metro were analyzed. Characteristics of 35kV power system were expounded, problems in application of overcurrent protection zones were analyzed and related improvements were also provided. Time delay instantaneous overcurrent protection for main transformer should be set to clear faults in main transformer 35kV outlet rapidly. Circuit breakers controlled by time delay instantaneous overcurrent protection for main transformer and 35kV backup protection for main transformer and zero sequence current protection for earth transformer were changed by variation of power system operating modes. Operating mode of protection for sectionalized circuit breakers of 35kV busbar in step-down/traction substations were changed by variation of power system operating modes and its related setting values were also changed.
闫石, 钟素梅. 地铁35kV供电系统继电保护分析[J]. 电气技术, 2019, 20(12): 79-82.
Yan Shi, Zhong Sumei. Analysis of 35kV power system protective relaying of metro. Electrical Engineering, 2019, 20(12): 79-82.
2019, Vol. 20 
