文档名：跟网型变换器的小扰动同步稳定机理分析与致稳控制
摘要：弱电网下,跟网型变换器易出现因阻尼不足导致的小扰动同步失稳问题.为此,该文借鉴复转矩分析理论,计及复杂控制耦合,建立跟网型变换器的复转矩模型.量化多环控制耦合、线路阻抗、控制参数等因素对系统阻尼转矩的影响,从阻尼的角度揭示跟网型变换器的小扰动同步失稳机理.根据理论分析,提出一种基于相位补偿的锁相环阻尼重塑控制策略,通过补偿多环控制耦合引入的负阻尼,增强变换器的小扰动同步稳定性.最后,开展相应的仿真与实验,验证理论分析的正确性与改进控制策略的有效性.
Abstract：Withtheincreasingintegrationofrenewableenergyandpowerelectronicequipment,thepowersystemischaracterizedbylowinertiaandweakdamping.Consequently,grid-followingconvertersemployingaphase-lockedloop(PLL)forsynchronizationfacetheriskofoscillationinstability,especiallyincomplexcontrolcoupling.Thispaperproposesacomplextorqueanalysismodelthatexaminesthedampingmechanismforsmalldisturbancesynchronousinstability.Torevealthesmalldisturbancesynchronizationinstabilitymechanismofgrid-followingconverters,aPLLcomplextorqueanalysismodeisbuiltconsideringthecurrentcontrol(CC)loopandDC-linkvoltagecontrol(DVC)loop.Accordingly,theaccuratedampingcharacteristicsandoscillationriskofthelow-frequencymodecanbeassessed.Theeffectsoftypicalmulti-loopcontrolcoupling,lineimpedance,andcontrolparametersonthedampingtorqueofthesystemarequantified.Firstly,atypicalgrid-followingtopologyandcontrolstrategyisintroduced,includingthePLL,currentinnercurrentloop,andDC-linkvoltageouterloop.Secondly,asynchronousdynamicanalysismodelisestablished,consideringbothCCandDVC,resemblinginthePhillips-Heffronmodelusedinlow-frequencyoscillationanalysisforsynchronousmachines.Basedontheequivalentblockdiagramtransformation,thecomplextorquemodelofthesynchronousloopisderived,enablingtheexaminationofequivalentsecond-ordermotiondrivenbyunbalancedvoltage,asshowninFig.A1.ItindicatesthatbyintroducingequivalentvoltagecomponentsbyCCandDVC,controlcouplinghasanuncertaindampingeffectonthePLL.Thirdly,theintrinsicdampingofPLLandadditionaldampingfromCCandDVCareextractedusingthedevelopedmodel,facilitatinganinvestigationintotheinfluenceofcontrolinteractiononthePLL'sequivalentmotion.Moreover,thestudyanalyzestheimpactsofmulti-loopcontrolcoupling,lineimpedance,andvariouscontrolparametersonthelow-frequencyoscillationcharacteristicsofgrid-followingsystems.Finally,adampingcompensator,utilizingd-axiscurrentfeedback,isproposedtoimprovethelow-frequencydampingcharacteristicsofgrid-followingandenhancethesmallperturbationsynchronizationstabilityoftheconverter.Theresultsshowthatincorrectcontrollerparameterscanleadtosynchronizationinstabilitywithoscillationfrequenciesbelow10Hz,particularlyinweakgrids.Theinfluenceofkeyparametersonthesystem'soscillationmodeissummarizedasfollows:(1)IncreasingtheproportionalcoefficientofPLLandtheintegrationparameterofCCcanleadtoahigheroscillationfrequencyandexacerbatethenegativedampingeffect.(2)AmplifyingtheproportionalgainintheCCloopandDVCenhancesthesystem'soscillationfrequencybutweakensthenegativedampingeffect.(3)Theincreaseinthegridimpedancereducestheoscillationfrequencyandintensifiesthenegativedampingeffectofthesystem.Furthermore,leveragingtheenhancedPLL,thesystemexhibitspositivedampingandremainsstableasthegridtransitionsfromstrongtoweak.Asthegridimpedanceincreasesfrom0.1(pu)to0.8(pu),thepositivedampingpersists,signifyinganimproveddynamiccharacteristicofthegrid-followingsystem.
作者：李红 梁军杨 王振民 李国进 陈延明 Author：LiHong LiangJunyang WangZhenmin LiGuojin ChenYanming
作者单位：广西大学广西电力系统最优化与节能技术重点实验室南宁530004华南理工大学机械与汽车工程学院广州510640
刊名：电工技术学报 ISTICEIPKU
Journal：TransactionsofChinaElectrotechnicalSociety
年，卷(期)：2024, 39(12)
分类号：TM464
关键词：跟网型变换器 小扰动同步稳定 多环控制耦合 复转矩分析法 阻尼重塑
Keywords：Gridfollowingconverter smallsignalsynchronizationstability multi-loopcontrolcoupling complextorqueanalysis dampingreshaping
机标分类号：TQ325.3R242TM464
在线出版日期：2024年7月19日
基金项目：国家自然科学基金，广东省基础与应用基础研究基金-粤桂联合基金-重点项目跟网型变换器的小扰动同步稳定机理分析与致稳控制[
期刊论文] 电工技术学报--2024, 39(12)李红 梁军杨 王振民 李国进 陈延明弱电网下,跟网型变换器易出现因阻尼不足导致的小扰动同步失稳问题.为此,该文借鉴复转矩分析理论,计及复杂控制耦合,建立跟网型变换器的复转矩模型.量化多环控制耦合、线路阻抗、控制参数等因素对系统阻尼转矩的影响,从阻...参考文献和引证文献
参考文献
引证文献
本文读者也读过
相似文献
相关博文
跟网型变换器的小扰动同步稳定机理分析与致稳控制 Small Signal Synchronization Stability Analysis and Improved Control Strategy for Grid Following Converter
跟网型变换器的小扰动同步稳定机理分析与致稳控制.pdf
- 文件大小:
- 2.97 MB
- 下载次数:
- 60
-
高速下载
|
|
