混流式水轮机调节系统的建模与非线性动力分析

为深入探究混流式水轮机调节系统的非线性本质,在发电机组额定工况运行时有小波动的情况下,考虑水轮机及发电机的非线性特性,建立了一个新的水轮机调节系统非线性数学模型.在此基础上通过分岔图、时域图、相轨迹图及Poincare图分析了水轮机调节系统在压力管道流量变化、电网频率扰动以及负荷变化3种情况下的复杂非线性动力学特性.通过数值模拟得到了系统在稳定、临界及失稳情况时调节器的参数范围,并且得出当参数远离分岔点时有利于水轮机调节系统的收敛与稳定,为保证系统安全稳定地运行提供了理论依据.

Modeling and nonlinear dynamic analysis of Francis hydro-turbine governing system

In order to study the nonlinear dynamic behavior of hydro-turbine governing system,a new mathematical model of the system with nonlinearity is established,which reflects the rated condition of the whole system in small disturbance.The complex nonlinear dynamic behavior of this model is analyzed when the flow of pressure pipeline changes,the grid frequency disturbs and the network load changes,based on bifurcation diagram,time maps,phase picture and Poincare maps.Through numerical simulation,the parameter range of the system in a stable,critical and unstable situation is got;it is shown that the regulator parameters far from bifurcation points will be advantageous to the convergence and stability of the system.This paper provides a theoretical basis to ensure the system safely and stably operates.