采用通量线-有限元混合方法求解有风条件下直流输电线路离子流场  

A Flux Tracing-Finite Element Hybrid Method for Calculating Ion-Flow Field of HVDC Overhead Lines in Presence of Wind

作　　者：乔骥 葛小宁[2] 邹军 Qiao Ji;Ge Xiaoning;Zou Jun(State Key Laboratory of Power Grid Environmental Protection,Wuhan 430074 China;State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering,Tsinghua University,Beijing 100084 China)

机构地区：[1]电网环境保护国家重点实验室,武汉430074 [2]电力系统及发电设备控制和仿真国家重点实验室(清华大学电机系),北京100084

出　　处：《电工技术学报》2019年第5期910-916,共7页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金面上项目(51577103);电网环境保护国家重点实验室开放基金(GYW51201700589)资助

摘　　要：直流输电线路电晕产生的空间电荷在直流电场力的作用下形成离子流,会显著增强地面电场强度。结合通量线法和有限元法各自的特点,提出一种混合方法求解离子流场,在分裂导线周围的区域采用通量线法,在远离导线的区域采用有限元法,各区域之间采用D-N交替法进行耦合计算。一方面,仅在导线周围采用通量线法,避免了通量线法在全空间由于Deutsch假设产生的误差,并且可以考虑风速影响;另一方面,分裂导线周围不需要网格剖分,能够有效减少有限元网格节点数量,提高有限元计算效率。同时通量线法能够为有限元法提供交界面的初始值,耦合迭代在较少步数内即可收敛。计算结果与实验结果吻合较好,求解效率得到提高。最后,采用该方法对±800 kV与±500 kV直流同塔双回线路地面电场强度与离子流密度进行了预测分析。The space charges generated from the conductors of HVDC transmission lines due to the corona will form the ion-flow flied and enhance the electric field on the ground level. In this paper, a new hybrid method is proposed. The flux tracing method is used in ambient space of conductors while the upstream finite element method is applied in the space far away from the conductors. D-N algorithm is used to compute the coupling in each domain. On one hand, the error due to Deutsch assumption in flux tracing method is avoided. The influence of the wind can be included. On the other hand, the element number of the finite element is significantly reduced and the computational efficiency is improved. Moreover, the initial values on the interface can be provided by the flux tracing method. The iteration can be finished within a few steps. The calculations agree well with the experiment data and the efficiency is improved. Finally, the ground-level electric field and ion current density of ±800 kV and ±500 kV double-circuit lines are analyzed.

关 键 词：离子流 直流输电线路 通量线法 上流有限元法 区域分解法 

分 类 号：TM15[电气工程—电工理论与新技术]