主导模态保持的风电场站自适应等值方法  

Self-adaptive Equivalence Method for Wind Farm with Maintained Dominant Mode

作　　者：何君毅 周瑀涵 王康 李立 李子恒 辛焕海[1] HE Junyi;ZHOU Yuhan;WANG Kang;LI Li;LI Ziheng;XIN Huanhai(College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China;Dispatching and Control Center of State Grid Shaanxi Electric Power Company,Xi’an 710048,China)

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027 [2]国网陕西省电力公司调控中心,陕西省西安市710048

出　　处：《电力系统自动化》2021年第11期28-36,共9页Automation of Electric Power Systems

基　　金：国网陕西省电力公司科技项目“高比例新能源电力系统优化运行及安全消纳关键技术研究”资助。

摘　　要：局部区域中风机密集并网导致模型稳定分析困难,而传统单机等值难以有效保留系统动态特性,针对这一问题,文中从小干扰稳定角度提出一种主导模态保持的风电场站自适应等值方法。首先,将机组的小干扰阻抗模型折算到外电网回路并解耦,以实现数学形式上机组动态的分离;其次,根据主导模态下设备侧特征根和单馈入系统对应特征值的大小关系,确定该模态下机组的分群与聚合;最后,计算等值参数,构建等值网络。该方法在不同频段下保留的机组数目不同,有效保持了等值前后系统主导模态不变,MATLAB/Simulink平台上的仿真结果验证了该等值方法的合理性。Intensive grid-connection of wind turbines in a local area makes it difficult to analyze the model stability,while traditional single-machine equivalence is difficult to effectively retain the dynamic characteristics of the system.Aiming at this problem,this paper proposes a self-adaptive equivalence method for wind farms with maintained dominant mode from the perspective of small disturbance stability.Firstly,the small disturbance impedance model of units is converted to the external grid current and decoupled,which realizes the dynamic separation of turbines in the mathematical form.Secondly,according to the value relationship between the eigenvalues on the equipment side and the corresponding eigenvalues of the single infeed system in the dominant mode,the clustering and aggregation of units in this mode are determined.Finally,the equivalence parameters are calculated and the equivalence network model is built.In different frequency bands,the number of units reserved by this method is different,which effectively maintains the dominant mode of the system before and after the equivalence.The simulation results on the MATLAB/Simulink platform illustrate the rationality of the equivalence method.

关 键 词：小干扰稳定性 主导模态 广义短路比 自适应等值 

分 类 号：TM614[电气工程—电力系统及自动化]