中文摘要：

弱阻尼低频振荡是影响大规模互联电网安全稳定运行的主要因素之一。观察广域测量系统实测信号发现,电力系统正常运行过程中,因持续存在的负荷变化等随机性质的小幅扰动,导致系统响应始终存在小幅波动现象,这种类噪声信号数据量丰富且易于获得。文中提出基于随机减量技术和Prony方法实现电力系统低频振荡类噪声辨识。首先采用随机减量技术从类噪声信号中提取自由衰减信号,分析不同触发条件的适用性;进一步采用Prony方法拟合自由衰减信号,实现对系统低频振荡模式参数的估计;最后将该方法应用于处理36节点系统仿真信号和中国南方电网实测信号,证明其准确性。

英文摘要：

The weakly damped low frequency oscillation is one of the main factors that influence the stable operation of interconnected power grids.Observed from the wide area measured data,small fluctuations caused by load random changes exist continuously in power grids,which can be called ambient signals.A method is proposed to identify the low frequency oscillation characteristics from ambient data,using the random decrement technique and Prony method.First,the free-damped signal is extracted from ambient signal by the random decrement technique,and the applicability of three triggering conditions is discussed.Then the electromechanical properties are estimated from the free-damped signal using Prony method.This approach is applied to the simulation data from the 36-node benchmark system and the measured data in China Southern power grid,and the feasibility of this method is validated.