含SVG的双馈系统切换型次同步振荡及其非光滑分岔特性分析  

Analysis of Switched Subsynchronous Oscillation and Its Non-smooth Bifurcation Characteristics in Doubly-fed System With SVG

作　　者：薛安成 王永杰 付潇宇 乔登科 王子哲 XUE Ancheng;WANG Yongjie;FU Xiaoyu;QIAO Dengke;WANG Zizhe(State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,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

出　　处：《电网技术》2021年第3期918-925,共8页Power System Technology

基　　金：国家重点研发计划项目(2017YFB0902000,2017YFB 0902004)。

摘　　要：研究表明,改善电压稳定的无功补偿装置SVG(static var generator)可与双馈风机作用,形成次同步振荡,威胁电网安全。但其机理尚未完全明晰。有鉴于此,研究了含SVG的双馈系统的次同步振荡,说明其机理之一为限幅饱和引起的切换型振荡,并从非光滑分岔角度,分析切换型振荡随参数变化特性。具体的,首先介绍了切换型振荡和非光滑分岔,以及含SVG的双馈系统及其限幅环节;其次分析了含有SVG的双馈系统的切换型次同步振荡现象,并说明其是由限幅饱和引起的切换型振荡;然后分析了SVG不同控制参数对切换型次同步振荡的影响,确定与系统振荡相关的主要因素,给出了切换型振荡对SVG控制参数的非光滑分岔特性;最后分析了系统外部短路容量和故障严重程度对切换型振荡的影响,揭示了外部参数的非光滑分岔特性。Studies have shown that SVG(static var generator),a reactive power compensation device that improves voltage stability,may interact with DFIG to form sub-synchronous oscillations,threatening the safety of the power grid.However,the mechanism of this function has not yet been fully clear.This paper studies the subsynchronous oscillation of the doubly-fed system with SVG,which shows that one of the reasons is the switching oscillation caused by the limiting saturation.From the perspective of non-smooth bifurcation thereby,the characteristics of switching oscillation with parameters are analyzed.Firstly,the non-smooth bifurcation theory,the switching oscillation,and the limiting link of the doubly-fed system with SVG are introduced.Secondly,the switching subsynchronous oscillation phenomenon of the doubly-fed system with SVG is analyzed,which reveals that it is the limiting saturation that causes the switching oscillation.Thirdly,the influence of different control parameters of SVG on the switching subsynchronous oscillation is analyzed,confirming the main factors related to system oscillation and showing the non-smooth bifurcation characteristics of switching oscillation on SVG control parameters.Finally,the influence of the external short-circuit capacity and the severity of the fault on the switching oscillation is analyzed,revealing the non-smooth bifurcation characteristics of the external parameters.

关 键 词：切换型次同步振荡 非光滑分岔 双馈风机 SVG 限幅饱和 

分 类 号：TM614[电气工程—电力系统及自动化]