分布式电站宽频域谐振机理分析及阻抗协调构造方法  

Investigation on Resonance Mechanism in Wide Frequency Domain for Distributed Power Plant and Its Coordinated Impedance Shaping Method

作　　者：陈智勇[1] 黄旭程[1] 杨苓[1] 罗安[1] 黎燕[1] 杨均权 CHEN Zhiyong;HUANG Xucheng;YANG Ling;LUO An;LI Yan;YANG Junquan(National Electric Power Conversion and Control Engineering Technology Research Center (Hunan University), Changsha 410082,Hunan Province,China)

机构地区：[1]国家电能变换与控制工程技术研究中心(湖南大学),湖南省长沙市410082

出　　处：《中国电机工程学报》2019年第1期141-154,共14页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51477045;51807055);中国博士后科学基金项目(2017M622572)~~

摘　　要：分布式电站内部网络普遍存在宽频域阻抗耦合,具备宽频域谐振条件,且在分布式发电单元发射的宽频、高次谐波电流的影响下,极易放大特征谐波电流。该文旨在揭示此类型电站宽频域谐波谐振现象并解决此问题,建立典型分布式电站阻抗模型;分析电站宽频域谐振带的分布特征,并按激发因素的差异对谐振带进行归类;设计一种包含有源及无源阻尼装置的阻抗协调构造方法,实现对电站宽频域谐振阻尼效果。仿真和实验结果表明:1)谐波电流在传播过程中存在劣化趋势;2)电站存在以集电馈线为单元之间的阻抗耦合引起的宽频域谐振;3)所提出的阻抗构造方法能够降低电站与配电网之间、集电馈线为单元之间的阻抗耦合程度,满足电站谐波谐振治理需求。Impedance coupling in wide frequency domain is generally existed within the network of distributed power plants, which has the potential for wide frequency resonance. And the characteristic harmonic currents could be magnified under the impact of the wide frequency and high order harmonic currents supplied by distributed generation units. For the sake of exploring wide frequency harmonic resonance phenomena as well as resolving these problems, an impedance model for a typical distributed power plant, firstly, was established. Secondly, the distribution of these resonance bands was explicitly investigated and the types of them were classified in terms of different mechanisms. Next, an impedance shaping method, which coordinated an active damping device and a passive damping device, was proposed to damp wide frequency resonance. Finally, some simulation and experimental results are indicated that: 1) the deterioration tendency of harmonic currents does exist during the propagation along the feeders;2) the impedance coupling among the network units of each collector feeder could cause the wide frequency resonance. 3) the proposed impedance shaping method is capable of reducing the impedance coupling not only between the plant and the distributed grid but also among the network units with regard to each collector feeder. Also, the demands for harmonic resonance control of the plants could be fulfilled.

关 键 词：分布式能源电站 分布式发电单元 宽频域 阻抗耦合 谐波谐振 有源阻尼 

分 类 号：TM614[电气工程—电力系统及自动化]