基于最大测点正常率的线路参数增广状态估计方法

线路参数误差会导致状态估计不准确,进而影响能量管理系统的高级应用。基于加权最小二乘的增广状态估计法是一种有代表性的线路参数估计方法,但该方法存在易受量测误差影响等问题。基于测量不确定度理论,提出了一种以最大测点正常率(MNMR)为目标函数的线路参数增广状态估计新方法。与传统增广状态估计方法不同,该方法基于测量不确定度信息,目标是使测点的正常率最大,同时考虑电力系统实际的潮流和物理约束信息。此外,采用高斯核密度估计和点估计方法来提取参数估计结果的统计特征。仿真实验表明,所述方法继承了MNMR抗差状态估计的"抗差"特性,辨识结果不易受量测误差影响,能得到更加合理的线路参数。

An Augmented State Estimation Method for Transmission Line Parameters Based on Maximum Normal Measurement Rate

The errors of transmission line parameters will lead to inaccurate results of state estimation (SE) of the energy management system (EMS), thus affecting other advanced applications. The augmented state estimation (ASE) based on weighted least square is one of the representative estimation methods for transmission line parameters, but this method is prone to problems such as the measurement error. Based on the theory of uncertainty in measurement, a novel parameter estimation method, the ASE with the maximum normal measurement rate (MNMR) as its objective function, is proposed. Unlike the traditional ASE method, the proposed method is aimed at maximizing the normal measurement rate (NMR) based on the information of uncertainty in measurement, while taking into account the actual power flow and physical constraints of the power system. Furthermore, Gauss kernel density estimation and point estimation are used to extract the statistical characteristics of estimation results. Simulation results show that the proposed method has inherited the robust characteristic of MNMR robust SE, which is not easily affected by measurement error and can yield more rational parameters.