水轮发电机组低频振荡机理与稳定特性

Low frequency oscillation mechanism and stability characteristics of hydraulic turbine generator units

为深入探究水轮发电机组低频振荡机理,揭示系统稳定性规律,本文利用压力引水管道弹性模型、调速器模型和三阶发电机模型,建立水轮发电机组非线性数学模型。通过数值模拟来验证所建水轮发电机组模型与实际系统的一致性和正确性。进一步地,根据水轮发电机组阻尼特性,优化PID参数,系统分析了随调速器参数变化水轮发电机组的低频振荡机理及稳定特性。此外,为了定量探究关键参数对系统稳定性的影响规律,对处于稳定振荡模式下的系统进行阻尼灵敏度分析,得到了对系统稳定性影响较为显著的关键参数。研究成果为机组稳定运行提供理论依据和技术支撑。

To intensive study the low frequency oscillation mechanism of hydraulic turbine generator units and reveal the stability behaviors of the system,this study develops a dynamic model of a turbine generator unit coupling a hydraulic turbine model,a governor model,and a third order generator model.First,the dynamic model is verified against the prototype measurements of the turbine generator unit.Then,according to the damping characteristics of the unit,we optimize its PID parameters through numerical experiments and analyze the mechanism of low frequency oscillations and the stability characteristics of the system under different governor parameters.Finally,to evaluate quantitatively the influence of sensitive parameters on system stability,damping sensitivity of the system in the steady oscillation mode is examined,and key parameters significant to system stability are determined.