基于广域测量信息在线辨识低频振荡

全国电网的互联使区域间的低频振荡成为威胁系统稳定的关键因素之一,而基于全球定位系统（GPS）的广域测量系统（WAMS）的发展和应用为在线分析区间低频振荡模式乃至控制提供了新契机.因而,研究区间低频振荡模式的在线辨识算法成为实现低频振荡在线监测以及进行阻尼控制的重要理论问题.该文在讨论Prony方法本质的基础上,给出了一种新的模型阶数估计方法,提出根据广域测量系统（WAMS）的测量信息,采用多机组的功角及转速变量进行低频振荡辨识.结合工程实际提出了基于（WAMS）的研究低频振荡问题的实现方案,包括启动判据、数据预处理、阶次估计、模式提取和综合分析等步骤.8机36节点的算例结果表明：该方案具有系统性、直接性、噪声干扰小的特点,为低频振荡的监测和控制创造了条件.

ONLINE IDENTIFICATION OF LOW-FREQUENCY OSCILLATIONS BASED ON WIDE-ARER MEASUREMENTS

With interconnection of power system, inter-area low frequency oscillation has become one of the serious factors affecting interconnected power system stability, while the application and development of wide-area measurements based on Global Positioning System(GPS) have provided a new approach for online identification and control of low-frequency oscillations models. The online identification method of researching inter-area low frequency oscillation has become an important academic question for achieving online detection and damping control of low-frequency oscillations.Based on discussing the essence of Prony method, this paper gives a new method for model order estimation, and then proposes to use the angles and speeds of multi generators in low-frequency oscillation monitoring. The paper presents an implemental scheme based on WAMS, including starting criteria, signal processing, model order estimation, mode analysis and so on. Finally, this algorithm is tested in an example of EPRI-36(CHINA) system. The results demonstrate that the method is effective for monitoring and control of low frequency oscillations in interconnected power systems.