构网场景下SVI多机并联功频振荡分析及抑制  

Analysis and suppression of power⁃frequency oscillation of SVI multi⁃unit parallelconnection under grid⁃forming scenario

作　　者：陈伟 周少泽 雷心宇 宋昕哲 韦徵 王伟 CHEN Wei;ZHOU Shaoze;LEI Xinyu;SONG Xinzhe;WEI Zheng;WANG Wei(NARI Group Corporation(State Grid Electric Power Research Institute),Nanjing 210000,China;School of Electrical and Automation Engineering,Nanjing Normal University,Nanjing 210000,China)

机构地区：[1]南瑞集团(国网电力科学研究院)有限公司,江苏南京210000 [2]南京师范大学电气与自动化工程学院,江苏南京210000

出　　处：《现代电子技术》2023年第19期129-134,共6页Modern Electronics Technique

基　　金：国家重点研发计划项目(2022YFB2402700);国家电网公司科学技术项目:计及暂态控制切换特性的构网型新能源发电单元并网稳定性分析与镇定技术研究。

摘　　要：随着新能源发电的占比不断提高,电力系统振荡问题日趋严重。文中针对构网场景下自同步电压源逆变器(SVI)多机并联出现的功频振荡问题展开分析。首先,基于SVI的控制策略通过小信号模型详细分析了多机并联的振荡机理,得出振荡的主要原因为SVI之间参数不一致,其中主要影响参数有惯量系数、有功下垂系数和线路电抗;然后,基于功率微分的预知特性提出一种互阻尼振荡抑制策略,利用功率微分项实时反馈校正有功参考可以起到功率阻尼的作用,无需相邻机组之间通信即可达到抑制振荡的效果,提高了系统的稳定性和可靠性;同时基于系统传递函数的根轨迹给出互阻尼参数的设计方法;最后,通过仿真验证了机理分析的正确性和抑制策略的有效性。With the increasing share of new energy generation,the power system oscillation problem is becoming more and more serious.In this paper,the power⁃frequency oscillation problem of the self⁃synchronous voltage⁃source inverter(SVI)multi⁃unit parallel connection under the grid⁃forming scenario is analyzed.On the basis of the SVI control strategy,the oscillation mechanism of multi⁃unit parallel connection is analyzed in detail by means of a small⁃signal model,and it is concluded that the main cause of oscillation is the inconsistency of SVI parameters,among which the main influencing parameters are inertia coefficient,active sag coefficient and line reactance.Then,a mutual damping oscillation suppression strategy is proposed based on the predictive property of power differential.Real⁃time feedback and correction of the active reference by power differential term can play the role of power damping,and the oscillation can be suppressed without the communication between adjacent units,which improve the stability and reliability of the system.Meanwhile,the design method of mutual damping parameters is given based on the root locus of the system transfer function.The correctness of the mechanism analysis and the effectiveness of the suppression strategy are verified by simulation.

关 键 词：新能源发电 自同步电压源 SVI 多机并联 功频振荡 小信号模型 根轨迹 

分 类 号：TN751-34[电子电信—电路与系统] TM464[电气工程—电器]