500kV垂直紧凑型同塔双回带电检修方式分析

Analysis of Charged Maintenance Method on 500kV One-tower Double-circuit Transmission Lines

500kV同塔双回垂直排列型输电线路可有效提高自然输送功率、减小线路走廊宽度,从而降低线路综合造价,应用前景广阔。以5SCZ杆塔为例,当双回线路均带电时,从典型带电作业位置危险率和作业人员体表场强两个方面评价了带电作业可行性。结果表明,5SCZ2杆塔各典型带电作业位置危险率均小于1.0×10-5,作业人员可安全作业。等电位作业位置时,作业人员体表场强最大为383.69kV/m,为保证作业人员安全,等电位人员应穿40dB的屏蔽服。地电位作业位置时,作业人员体表场强最大为121.77kV/m,建议穿20dB的屏蔽服。当一回线路停运时,应在挂设接地线的基础上,增设个人保安线,才不会对作业人员的安全造成威胁。研究成果可为500kV垂直紧凑型同塔双回带电作业提供指导。

The 500 kV vertical one-tower double-circuit transmission line has some advantages,such as improving natural transmission power effectively,reducing the line corridor width and line comprehensive cost.So,it has very broad application prospects.Taking the 5SCZ tower for an example,the live working feasibility was evaluated according to operation hazard rate of typical live operation position and the electric intensity of operators' body when the double circuits are all energized.The results show that the hazard rate of every typical live operation in 5SCZ2 tower are all less than 1.0×10-5,which can guarantee operators working safely.But the operators' body surface electric intensity reached 383.69kV/m maximum when operators operating in equal potentials position in which case operators should wear shielding clothing with minimum 40 dB ratio for safety guarantee.Also operators should wear shielding clothing with minimum 20 dB ratio for safety guarantee when body surface electric intensity reached 121.77kV/m maximum while operating in equal potentials position.And additional personal security line should be laid after setting ground wire for eliminating all safety risks in condition of outage in first circuit.This reach can provide guidance for live working in 500 kV vertical compact one-tower double-circuit transmission line.