基于变量代换内点法的加权最小绝对值抗差状态估计

传统内点法加权最小绝对值(WLAV)抗差状态估计能够抑制坏数据影响,提高状态估计精度,但该方法模型复杂,计算效率低,限制了其工程应用价值。文中提出一种基于变量代换内点法的电力系统WLAV估计方法,该方法通过添加中间变量,将非线性量测方程分解为两步线性方程和两步非线性变换,并建立两步线性方程的WLAV估计数学模型。与传统内点法WLAV抗差状态估计相比,该方法无须形成海森矩阵,可有效提高迭代方程中系数矩阵的稀疏度,并减小矩阵的阶数,有效提高WLAV状态估计的计算速度。基于美国电气与电子工程师学会(IEEE)标准系统、波兰电网和国内某省网的仿真结果验证了所述方法的有效性,具有良好的工程应用前景。

WLAV Robust State Estimation Based on Variable Substitution Interior Point Method

Despite the ability of the traditional weighted least absolute value (WLAV) robust state estimation based on the interior point method (IPM) to improve the estimation accuracy by minimizing the impact of bad data, its practical application is limited because of low efficiency and complex model. A method based on variable substitution IPM is presented that has the nonlinear measurement equations decomposed into two linear equations and two nonlinear transformations by introducing auxiliary variables and the development of two linear WLAV estimation models. The linear WLAV robust state estimation model based on IPM is able to increase the sparsity of the coefficient matrix without calculation of Hessian matrix while reducing the matrix dimension to increase the state estimation speed. Simulation results based on Institute of Electrical and Electronics Engineers (IEEE) benchmark system, Polish grid network and a provincial grid of China demonstrate the effectiveness of the proposed method. Compared with traditional WLAV robust estimation based on IPM, the proposed approach is better able to improve computation speed with good prospects for engineering application. This work is supported by State Grid Corporation of China and National Natural Science Foundation of China (No. 51107032, No. 51277052, No. 61104045).