基于戴维南等值模型的静稳极限在线监视

摘要

基于实时测量信息的戴维南等值方法，为多机系统输电通道静稳极限在线监视提供了新的研究思路。本文结合电力系统实际运行状态的特点，通过分析戴维南等值方法的适用条件，提出一种内电势相角可变的戴维南等值模型，并使用具有可变遗忘因子的改进递推最小二乘法在线辨识戴维南等值参数，从而将多机系统等值成双机系统；利用等值后的双机系统快速求取输电通道的静稳极限；借助输电通道静稳极限的求取思路，文中也给出了在线监视多机系统静态稳定水平分布的方法。对IEEE39节点系统进行仿真，仿真结果表明本文计算方法能够较好地辨识戴维南等值参数，可有效估计输电通道的静态稳定性。%Thevenin equivalent method based on real time measurement provides a new research approach for static stability limit transmission channel monitoring of multi-machines system.Combining the characteristics of the power system actual motion, through analyzing of the applicable conditions of Thevenin equivalent methods, a kind of Theve-nin equivalent model with variable potential phase angles is proposed in this paper.And recursive least squares with variable forgetting factors are used to get the Thevenin equivalent parameters, thus turning a multi-machines system in-to a dual system.Then, the static stability limit of transmission channel can be obtained quickly with the dual system. Moreover, the distribution of the static stability in the multi-machines online monitoring system can also be obtained easily with the help of the approach.The paper uses the IEEE39 system as a testing system.And the simulation re-sults demonstrate that the method proposed in this paper can identify the Thevenin equivalent parameters precisely and assess the static stability of the transmission channel effectively.