多直流馈入城市输电网谐波放大特性分析  

Analysis on Harmonic Amplification Characteristics of Urban Transmission Network With Multi-Infeed DC System

作　　者：金祖洋 杨洪耕[1] 潘爱强[2] 

机构地区：[1]四川大学电气信息学院,四川省成都市610065 [2]国网上海市电力公司电力科学研究院,上海市虹口区200437

出　　处：《电网技术》2016年第12期3857-3864,共8页Power System Technology

摘　　要：针对多直流馈入城市输电网直流落点谐波交互作用过程中出现的谐波放大问题,提出基于模态分析法的谐波放大解耦方法进行研究。考虑到谐波放大对节点的影响与系统结构参数和谐波源扰动相关,提出节点观测因子确定易受谐波放大影响的节点;注意到各直流落点谐波源对谐波放大激励程度的不同,引入谐波源激励因子评价其作用;关注到城市输电网高压长电缆的使用,电缆对地分布电容造成的影响不容忽视,提出元件模态灵敏度评估其与系统感性元件的感容耦合作用。应用所提方法对某多直流馈入城市输电网进行分析,确定了易受谐波放大影响的区域和各直流落点谐波源贡献,揭示了主要作用电缆长度对谐波放大的影响规律,为城市输电网电缆规划提供了参考。For harmonic amplification problems appearing in harmonic interaction process of DC terminals in urban transmission network with multi-infeed DC（MIDC） system, a harmonic amplification decoupling method based on modal analysis is proposed. Considering influence of harmonic amplification on node associated with system structure parameters and harmonic disturbance, node observation factor is proposed to determine nodes prone to be affected by harmonic amplification. Noticing that there exists difference in excitation degree of harmonic amplification among DC terminals＇ harmonic sources, harmonic source excitation factor is introduced to evaluate their effects. Focusing on use of HV long cables in urban transmission network, influence caused by distributed cable capacitances cannot be ignored. Therefore, element modal sensitivity is proposed to evaluate inductance-capacitance coupling effect between cables and inductive elements in the system. The proposed method is applied to an MIDC urban transmission network. The areas prone to be affected by harmonic amplification and contribution of harmonic source in each DC terminal are determined. Simulation results reveal influence rule of major cable length on harmonic amplification, providing a reference for cable planning of urban transmission network.

关 键 词：感容耦合 谐波放大 模态分析 节点观测因子 谐波源激励因子 元件模态灵敏度 

分 类 号：TM721[电气工程—电力系统及自动化]