复数域加权最小二乘法在相量量测状态估计中的应用

Application of Complex Field Weighted Least Square Algorithm in Phasor Measurement State Estimation

基于相量量测的状态估计能提高状态估计的精度,而相量测量单元在高电压等级网络中的广泛配置为电力系统全相量量测状态估计提供了坚实的硬件基础,研究全相量量测状态估计意义重大。建立了基于全相量量测状态估计的量测方程,在此基础上建立了复数加权最小二乘法(complex field weighted least square,CWLS)状态估计模型。文中还对复数域下相量的误差特性和CWLS算法的抗差性进行了研究,同时详细分析了CWLS算法中权重的选取和不良数据的辨识。仿真结果表明了所建模型的合理性以及CWLS算法的有效性和适应性。

Phasor measurement state estimation can improve the estimation accuracy of system state, and wide configuration of phasor measurement units （PMUs） in high-voltage power grid provides a firm hardware foundation for overall phasor measurement state estimation, so it is of great significance to research overall phasor measurement state estimation. A measurement equation in complex domain based on overall phasor measurement state estimation is established, and on this basis a state estimation model, which is solved by complex field weighted least square （CWLS） that needs no iteration to achieve estimation results, is built. Phasor error characteristics in complex domain and the robustness of CWLS algorithm are researched, and the selection of weights in CWLS algorithm and the identification of bad data are analyzed in depth. Simulation results show that the built model is reasonable and the CWLS algorithm is effective and adaptive.