自然激励下发电机有功参与因子提取及其在阻尼调制中的应用

Extraction of Participation Factor with Respect to Generation Active Power under Natural Excitation and Its Application in Damping Modulation

弱阻尼低频振荡是制约区域间传输功率、影响系统安全稳定的关键因素之一。针对系统运行过程中潜在的区间弱阻尼模式,提出一种随机数据驱动的基于发电机有功调制的区间模式阻尼提升策略。首先,以环境激励下系统随机响应为输入信号,利用子空间动态模式分解(SubDMD)算法在线提取弱阻尼模式下各发电机有功功率的参与因子,量化分析系统发电机有功出力在对应模式中的参与程度。进而,在Sub-DMD模态振型辨识结果基础上,依据模态相角将机组划分为两群,并结合区间断面潮流确定两群机组出力调整方向,准确定位送端区域和受端区域有功调制关键机组。最后,按照送端机组减出力,受端机组增出力的原则,并充分考虑参调发电机功率限额约束及实际调度操作可行性,构建仅依赖随机响应数据的互联电网阻尼在线提升策略。IEEE16机5区域系统和某实际电网仿真结果,验证了该方法在互联电网阻尼提升方面的可行性和有效性。

Poorly damped oscillation is a key factor that affects the stability of large-scale interconnected power grids and is one of the major problems that limit the power exchange capacity between different areas. Aiming at the poorly damped mode, this paper proposed ambient-data-driven participation-factor-based generation rescheduling strategy for enhancing interarea mode damping.Firstly, subspace dynamic mode decomposition(Sub-DMD) algorithm was used to calculate the participation factor with respect to generator active power online from ambient data, and the relationship between the generation output and the mode damping can be quantified. Based on the identification results of modal phase, the generators for rescheduling can be divided into two groups. Combining with the power flow of the regional section, the adjustment direction of the two groups can be determined.Therefore, the key generators for enhancing the damping in the sink and source can be accurately determined. Finally, based on the participation factor identification results, combing with the principle of reducing the generation output in the source and increasing that in the sink accordingly, and fully considering the power limit of the adjustable generators and actual rescheduling feasibility constraints,the online damping enhancement strategy solely relying on synchronized ambient data was realized. The numerical simulation of IEEE 16-generator 5-area system and a real system verify the effectiveness and feasibility of the proposed method in terms of interarea mode damping enhancement.