多回交叉跨越架空输电线下工频磁场计算方法  

Calculation of the Power-frequency Magnetic Field Under Multiple-circuit Cross-over Overhead Transmission Lines

作　　者：肖冬萍[1] 刘淮通 姜克儒 李松浓[2] 侯兴哲[2] 

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400044 [2]国家电网重庆市电力公司电力科学研究院,重庆市渝北区401123

出　　处：《中国电机工程学报》2016年第15期4127-4133,共7页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51407016);国网重庆市电力公司电力科技项目(SGCQDK00JZJS1400018)~~

摘　　要：随着我国电网快速发展,多回不同电压等级、不同结构的架空输电线路交叉跨越的情况增多,线下工频磁场是否满足国家电磁环境限值标准以及如何合理设计线路结构抑制线下磁场强度,都是亟待解决的新问题。对此,建立了架空输电线路三维磁场计算模型,考虑尽可能多的线路结构影响因素。将非平行架设的多回输电线分别置于不同的笛卡尔坐标系中,根据推导出的坐标变换关系,将多回线路产生的三维磁场统一在xyz坐标系中叠加形成合成磁场,以此解决计算复杂的问题。两个典型算例分析表明,所提出的方法,能够快速、准确地计算出交叉跨越输电线下的工频磁场,可在较大空间范围内反映磁场分布特征,具有良好的计算效率。分析得到线路结构、多回线路空间交叉位置关系、电流相序排列等因素对合成磁场的影响规律,可为受限于电磁环保标准要求的交叉跨越输电线结构设计和布局提供参考。With the rapid expansion of power grid in China, the phenomenon that multiple-circuit overhead transmission lines （OHTLs） cross over each other has been becoming increasingly common. For the new planning OHTLs, the problems of how to assess whether the power-frequency magnetic field meets the national standard of electromagnetic environment and how to design reasonably the lines＇ configuration to restrain the magnetic field have been urgent to be solved. Therefore, the 3D magnetic field calculation model was proposed so that as many influence factors of configurations on the magnetic field as possible would be taken into consideration. The non-parallel multiple-circuit OHTLs were put in different Cartesian coordinate systems. Based on the deduced transformation relational expressions between two coordinate systems, the magnetic fields generated by the multiple-circuit over-cross OHTLs were uniformly superposed and displayed in xyz coordinate system. The conversion algorithm solved the problem of complex calculation. The simulation analyses for two typical examples showed that the proposed methodology provides an easy-to-accomplish and effective way to predict the power-frequency magnetic field under multiple-circuit cross-over OHTLs. The approach made it possible to show the magnetic field distribution in a larger space area with excellent computing performance. The influence regulars of the OHTLs＇ configuration, the spatial relative location of the multiple-circuit OHTLs and the sequence of current phases are explored, which would be benefit for the configuration and layout design of multiple-circuit cross-over OHTLs to optimize the electromagnetic environment.

关 键 词：架空输电线 交叉跨越 工频磁场 三维 坐标变换 影响因素 

分 类 号：TM15[电气工程—电工理论与新技术] TM752