基于分层估计的戴维南等值阻抗在线计算方法  

Thevenin equivalent impedance online calculation method based on hierarchical estimation

作　　者：张森 王慧芳[1] 叶睿恺 ZHANG Sen;WANG Huifang;YE Ruikai(College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学电气工程学院,浙江杭州310027

出　　处：《电力系统保护与控制》2023年第12期90-98,共9页Power System Protection and Control

基　　金：国家自然科学基金联合基金项目资助(U2166204)。

摘　　要：戴维南等值阻抗在线计算可以应用于系统稳定性分析和继电保护在线整定等场景。在分析已有的两类戴维南等值阻抗在线计算方法原理、误差原因的基础上,提出了基于分层估计的戴维南等值阻抗计算方法。详细给出了该方法提出的依据和过程,并通过误差分析说明了该方法利用分层抽样的思想,根据负荷侧参数对样本进行分层,分别构建计算式,提高了计算精度,并有效克服系统戴维南等值阻抗的波动影响。算例分析表明,在等值电势各种幅度波动下,所提方法与已有的两类方法相比,能够在更少采样数量下识别出戴维南等值参数,并显著减小误差。在加入戴维南等值阻抗波动时,所提方法依然能估算出戴维南等值阻抗。The Thevenin equivalent impedance online calculation can be applied to system stability analysis and online tuning of relay protection.The method based on hierarchical estimation is suggested after two types of Thevenin equivalent impedance calculation method principles and error causes have been analyzed.The proposed method's foundation and steps are presented,and an error analysis reveals that it stratifies the samples in accordance with the parameters on the load side and builds the calculation formulas in a way that can increase calculation accuracy and successfully counteract the fluctuating effects of the system's Thevenin equivalent impedance.The example analysis demonstrates that,with varied amplitude disturbances of the equivalent potential,the proposed method can identify the Thevenin equivalent parameters with fewer sampling numbers.Also it greatly minimizes the error compared to the two current methods.It can still estimate the Thevenin equivalent impedance even when the Thevenin equivalent impedance disturbance is included.

关 键 词：参数估计 等值阻抗计算 继电保护 戴维南等值 

分 类 号：TM744[电气工程—电力系统及自动化]