次同步振荡在交直流电网中传播的关键影响因素  

Key Influencing Factors on Propagation of Sub-synchronous Oscillations in AC and DC Grids

作　　者：徐衍会[1] 刘慧 成蕴丹 XU Yanhui;LIU Hui;CHENG Yundan(School of Electrical and Electronic Engineering,North China Electric Power University,Changping District,Beijing 102206,China)

机构地区：[1]华北电力大学电气与电子工程学院,北京市昌平区102206

出　　处：《现代电力》2024年第2期219-229,共11页Modern Electric Power

基　　金：国家电网有限公司科技项目(5100-202199536A-0-5-ZN)。

摘　　要：随着“双高”电力系统的发展,次同步振荡问题日益凸出,亟需研究交直流线路次同步振荡传播的关键影响因素。从系统响应量测时序数据着手,提出了一种次同步振荡传播关键影响因素定量分析方法。首先,基于自适应噪声完全集合经验模态分解(complete ensemble empirical mode decomposition, CEEMDAN)的改进小波阈值去噪方法对量测数据进行降噪处理,减少噪声对Prony分析的影响;其次,基于次同步振荡传播各影响因素的相关系数和互信息量建立相关性评价组合模型;最后,计算交直流不同参数在综合模型中的评价指标,得出次同步振荡在交直流线路中传播的关键影响因素。通过在PSCAD搭建2区域4机系统进行分析,结果表明:影响交流线路次同步振荡传播的极强相关参数为交流线路潮流,影响直流线路次同步振荡传播的极强相关参数为次同步振荡频率下交流线路阻抗特性。With the development of power system containing high percentage of both renewable energy and power electronic devices the trouble caused by sub-synchronous oscillation becomes increasingly prominent,so it has to be settled urgently to research the key influencing factors on the propagation of subsynchronous oscillation in AC and DC transmission lines.For that reason,based on the system response measurement time series data,a quantitative analysis method for the key influencing factors of sub-synchronous oscillation propagation was proposed.Firstly,by use of the improved wavelet threshold noise reduction based on the adaptive noise complete ensemble empirical mode decomposition(abbr.CEEMDAN)the noise suppression of measured data was performed to reduce the affection of noise on the Prony analysis.Secondly,based on the correlation coefficient and mutual information of each influencing factor of subsynchronous oscillation propagation a combination model for correlation evaluation was established.Finally,by means of computing evaluation indices of different AC and DC parameters in comprehensive model,the key impacting factors of subsynchronous oscillation propagated in AC and DC transmission lines were obtained.Analysis results of a 2-region 4-machine system constructed in PSCAD show that the highly correlated parameter impacting the propagation of subsynchronous oscillation in AC transmission lines is the power flow in AC transmission lines and the highly correlated parameter impacting the propagation of subsynchronous oscillation in DC transmission lines is the impedance characteristics of AC transmission line under the subsynchronous oscillation frequency.

关 键 词：次同步振荡 PRONY算法 CEEMDAN分解 小波阈值去噪 相关性分析 

分 类 号：TM712[电气工程—电力系统及自动化]