水电站水力系统非线性动态模型仿真

Hydraulic System Nonlinear Dynamic Model Simulation for Hydropower Station

针对水电站水轮机水力系统不同结构形式,应用牛顿运动定律,建立了单压力引水管水力系统非线性动态模型、调压室-压力引水管水力系统非线性动态模型、一管多机水轮机水力系统非线性动态模型,模型考虑了压力引水管水体摩擦损失、调压室特性等因素对系统模型的影响。基于MATLAB仿真环境建立了水电站水力系统非线性动态仿真模型,仿真模型动态仿真了不同水力系统结构的非线性动态模型对水轮机输出功率及机组水头的影响,仿真结果表明:调压室-压力引水管系统非线性动态模型比单压力引水管系统非线性动态模型对水轮机输出功率影响大、输出功率震荡调节时间长;单压力引水管系统非线性动态模型可以近似看作一阶系统,调压室-压力引水管系统非线性动态模型可以近似看作二阶系统。一管多机系统中,机组输出功率、机组水头存在耦合影响,影响程度与机组水门相对开度有关。

According to different structure of hydraulic systems combined with hydro-turbine for hydropower plant,the hydraulic system model of individual penstock,surge-penstock and sametunnel with multi-unit was established respectively by applying the Newton＇s law of motion.The friction loss and surge characteristic were taken into account in these models.The hydraulic system nonlinear dynamic simulation model for hydropower station was constructed in MATLAB.The dynamical model simulated the effects of hydro-turbine output-power and unit water-head for different kinds of hydraulic system nonlinear dynamical model.Simulation results illustrate that hydraulic system model of surge-penstock has more powerful effect force than that of individual penstock hydraulic system for turbine output-power,and the regulating time of output-power is longer than that of individual penstock hydraulic system.From the point of control theory,the individual penstock hydraulic system model can be taken as one order system and surge-penstock hydraulic system model as two order system.For the sametunnel with multi-unit hydraulic system model,the output-power of individual unit is effected each other,whose effected degree does something with relative position of water valve.