多VSC并网系统的低频振荡分析及抑制  

Low-frequency Oscillation Analysis and Suppression of Multi-VSC Grid-connected System

作　　者：徐永海 秦本双 施红 贾焦心 XU Yonghai;QIN Benshuang;SHI Hong;JIA Jiaoxin(State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China;Electric Power Research Institute of State Grid Henan Electric Power Company,Zhengzhou 450052,Henan Province,China;Power China Henan Electric Power Survey&Design Institute,Zhengzhou 450007,Henan Province,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206 [2]国网河南省电力有限公司电力科学研究院,河南省郑州市450052 [3]中国电建集团河南省电力勘测设计研究院有限公司,河南省郑州市450007

出　　处：《电网技术》2022年第11期4316-4324,共9页Power System Technology

基　　金：国家自然科学基金项目(52207102);新能源电力系统国家重点实验室(华北电力大学)自主研究课题(LAPS2021-24)。

摘　　要：随着新能源并网渗透率的增加,高比例电压源型并网变换器(voltage source converter,VSC)接入电网,导致系统的惯性和阻尼显著降低,遭受扰动时易产生功率低频振荡,威胁系统安全稳定运行。采用机电比拟原理构建了电压控制型VSC(voltage-source controlled VSC,VC-VSC)和电流控制型VSC(current-source controlled VSC,CC-VSC)的机械导纳模型,并基于回路阻抗矩阵的模态分析法,对比研究当虚拟惯量常数和电网阻抗变化时VC-VSC和CC-VSC的低频振荡特性。在此基础上,进一步研究当仅可列写出系统部分基本回路阻抗矩阵时,模态分析法的适用性。针对VC-VSC和CC-VSC低频振荡特点的不同,分别提出其对应的抑制策略,并给出参数设计依据。最后,通过MATLAB/Simulink仿真模型验证VC-VSC和CC-VSC的低频振荡现象及其振荡抑制方法的有效性。With the increase of new energy grid penetration rate, a high proportion of voltage source converter(VSC) is connected to the power grid, which leads to a significant decrease in inertia and damping of the system. When the system is disturbed, it is easy to produce the low-frequency oscillation of power, threatening the safe and stable operation of the system. In this paper, the mechanical admittance models of the voltage-source controlled VSC(VC-VSC) and the current-source controlled VSC(CC-VSC) are constructed by using the electromechanical analogy principle. Based on the modal analysis of the loop impedance matrix, the variation laws of low-frequency oscillation characteristics of the VC-VSC and the CC-VSC are compared and analyzed when the virtual inertia constant and the grid impedance fluctuate. In addition, the applicability of the modal analysis is further studied when only some basic loops of the system can be listed. Aiming at the different characteristics of low-frequency oscillation between the VC-VSC and the CC-VSC, the corresponding low-frequency oscillation suppression strategies are proposed, respectively, and the basis for parameter designing is given. Finally, the low-frequency oscillation phenomena of the VC-VSC and the CC-VSC and the corresponding suppressions are verified based on the MATLAB/Simulink simulation model.

关 键 词：多VSC 低频振荡 模态分析 对比分析 振荡抑制 

分 类 号：TM721[电气工程—电力系统及自动化]