白浙线长江大跨越±800 kV/500 kV交直流混压段张力架线施工优化

Optimization of Tension Line Construction in±800 kV/500 kV AC-DC Mixed Voltage Section of the Yangtze River Crossing in Baizhe Line

通过对特高压白浙线工程±800 kV/500 kV交直流混压同塔架设池州长江大跨越段的导地线张力架设施工方案进行分析,结合该方案在实际施工中的表现,探讨提升大跨越段封航架线施工效率的主要方式和手段。这是国内首次采用±800 kV单回直流及下挂500 kV双回交流混压设计的特高压大跨越工程,跨越档距2 354 m,档内导地线总计38根,建造规模非比寻常,常规架线方法无法满足施工需要。经过方案对比研究,结合工程实际,分别针对±800 kV直流及500 kV交流采用2ד2牵3”及4ד1牵1”总体放线施工工艺,通过对放线滑车设置、牵张设备选型及场地布置、牵引绳索及船只配置等方面进行改进优化,有效减少了封航次数,缩短了施工工期,满足工程要求。经工程实践验证,采用该方案可在保障工程质量的基础上按工期要求完成全部施工任务。此技术对大跨越段架线的总体施工效率提升有重要意义。

Based on the analysis of the tension erection construction scheme of the guide ground for the±800 kV/500 kV AC-DC mixed tower erection in the Chizhou Yangtze River large span section of ultra high voltage(UHV)Baizhe Line project,combined with the performance of the scheme in the actual construction,the main ways and means to improve the construction efficiency of the large span closure overhead line are discussed.This is the first UHV large-span project that adopts±800 kV single-loop DC and 500 kV double-loop AC mixed-voltage design in China.The span distance is 2354 m,and there are 38 guide ground wires in the file.The construction scale is unusual,and conventional methods can not meet the construction needs.After a com-parative study of the schemes,combined with the actual engineering,the overall pay-off construction technolo-gy of 2ד2 pull 3”and 4ד1 pull 1”is adopted for±800 kV DC and 500 kV AC respectively,and the setting of pay-off block,the selection of stretching equipment and the layout of the site,the configuration of traction ropes and boats are improved and optimized.The number of times of sealing-off and construction period are re-duced effectively,and the requirements of the project are met.After the actual engineering verification,on the basis of ensuring the quality of the project,all the construction tasks have been completed according to the re-quirements of the construction period.This technology is of great significance to improve the overall efficiency of large span line erection.