多机并网系统的两带阻滤波器高频振荡抑制方法  

High-frequency Oscillation Suppression Method by Two Notch Filters for Multi-inverter Grid-connected System

作　　者：杨苓[1] 陈燕东[1] 罗安[1] 吕志鹏 陈智勇[1] YANG Ling;CHEN Yandong;LUO An;LU Zhipeng;CHEN Zhiyong(National Electric Power Conversion and Control Engineering Technology Research Center (Hunan University),Changsha 410082,Hunan Province,China;China Electric Power Research Institute,Haidian District,Beijing 100192,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 [2]中国电力科学研究院有限公司,北京市海淀区100192

出　　处：《中国电机工程学报》2019年第8期2242-2252,共11页Proceedings of the CSEE

基　　金：国家重点研发计划项目(2017YFB0902000);国家自然科学基金项目(51577056);国家电网公司科技项目(SGXJ0000KXJS1700841)~~

摘　　要：随着越来越多的逆变器在同一公共耦合点接入弱电网,多机与电网之间的阻抗耦合作用越来越严重,可能引起高频振荡,进一步加剧系统的不稳定。该文从逆变器输出阻抗的角度出发,指出逆变器输出阻抗在振荡频率处应设计得较高,而在其他频率处应设计得较低是实现振荡抑制的基本方法。为了实现所提出的基本方法,需要增加与原逆变器输出阻抗并联和串联的2个虚拟阻抗。为此,提出一种多机并联的两带阻滤波器高频振荡抑制方法,提高系统的整体阻尼。该方法在公共耦合点电压前馈和网侧电感电流反馈中引入带阻滤波器来达到并串联虚拟阻抗的实现形式。最后,实验结果验证所提方法的有效性。With plenty of parallel inverters connected to weak grid at the point of common coupling(PCC), the impedance coupling interactions between the inverters and the grid are enhanced, which may cause high-frequency oscillation and further aggravate the system instability. A basic technique from the viewpoint of inverter output impedance was proposed to take into account the oscillation suppression, showing that the inverter output impedance should be designed relatively high at the oscillation frequency, while relatively low at other frequencies. On the basis of the proposed technique, two virtual impedances were added to be in parallel and in series with the original inverter output impedance, respectively. Thus, the high-frequency oscillation suppression method by two notch filters was proposed to increase the whole system damping.The implementation forms of the virtual impedances were presented by the proposed PCC voltage feedforward and grid-side inductor current feedback with two notch filters.Finally, experimental results were provided to verify the validity of the proposed control method.

关 键 词：弱电网 多逆变器并联 高频振荡 带阻滤波器 阻抗重塑 

分 类 号：TM73[电气工程—电力系统及自动化]