市政电网对城市轨道交通信号系统的影响及其防护

Influence and Protection of Municipal Power Grid on Urban Rail Transit Signal System

针对市政电网线路的电磁干扰环境以及城市轨道交通信号设备的电磁兼容要求,根据电磁感应的理论公式和相关工程建设经验,定性地分析市政电网线路在正常和故障工作状态下对信号系统的电缆、轨道电路、信号室内设备的电磁干扰影响,提出电网和轨道交通等市政基础设施建设的综合规划和设计理念。为确保轨道交通运营的安全,结合理论计算和经验数据,提出电力线路对信号系统电磁干扰影响的距离要求和防护方案。结论为:当轨道交通信号系统设备的干线电缆与市政电力供电线路的平行长度大于1 km时,间距应不小于20 m,否则考虑采用屏蔽电缆;车辆段/停车场与市政电网架空线路的平行长度大于1 km时,间距应不小于50 m,否则车辆段/停车场的轨道电路不能采用单轨条50 Hz相敏轨道电路;轨道交通正线的信号设备室/控制中心与市政电网的间距大于或等于20 m;车辆段/停车场信号楼与市政电网的架空线路的间距宜大于或等于50 m。

In view of compatibility requirements on electromagnetic environment of the power supply lines of municipal power grid and the EMC requirements on urban rail transit signaling system, the EMI impacts on the cable, tract circuit, and equipment in SER of signaling system are analyzed qualitatively when the municipal power grid is in normal and fault working status respectively by using the theoretical equations and the related project construction experience. The integrated plan and design concept of municipal infrastructure construction such as power grid and rail transit, etc. is proposed. To ensure the safety of rail transit operation, theoreti- cal calculation and empirical data are used to find out the distance requirements to avoid the EMI impacts from the power supply lines on the signaling system and EMC protection solutions. When the main cable of rail transit signaling system parallels with power supply lines of more than lkm long, the separation distance must be more than 20m wide; otherwise, the shielding cable should be used： when the depot/yard parallels with municipal power aerial line of more than 1km long, the separation distance must be more than 50m wide; otherwise, the monorail 50Hz phase - sensitive track circuit cannot be adopted; the separation distance between the main line SEPUOCC and municipal power aerial line must be more than 20m wide, and the separation distance between the SER of depot/yard and municipal power aerial line should be more than 50m wide.