水泵水轮机全特性描述及可逆式机组非线性控制研究

发布时间：2018-05-07 15:19

本文选题：水泵水轮机 + 全特性空间曲面　；参考：《华中科技大学》2015年硕士论文

【摘要】：抽水蓄能电站具有调峰填谷、调频调相、旋转备用等快速响应的作用,为了解决电网的调峰问题,抽水蓄能电站势必会得到大力开发。但有两个重要因素制约我国抽水蓄能电站大力发展,其一是水泵水轮机全特性描述。水泵水轮机全特性描述是水利设计、过渡过程分析及控制规律研究的基础,传统的水泵水轮机全特性描述存在开度线聚集、交叉和扭转等现象,导致拟合困难及过渡过程计算存在多值问题。其二是抽水蓄能电站的高效稳定运行。水泵水轮机存在反“S”和驼峰两个运行不稳定区域,具有强非线性,传统的以线性理论为基础的控制规律不足以适配控制对象水泵水轮机的强非线性,不能从根本上以保障其高效稳定运行。针对以往全特性描述平面表示方法存在的问题,研究了基于空间曲面这一新的视角下的水泵水轮机全特性描述方法。这种全新的描述方法不存在开度线聚集、交叉和扭转等现象,在模型试验数据的基础上应用B样条理论构建全特性空间曲面,其开度线插值不存在多值性,并绘制了全特性空间曲面特征线,这是水泵水轮机全特性变化规律及控制规律研究的基础。针对线性控制理论不足以满足可逆式机组安全稳定运行需求,在空间曲面视角描述水泵水轮机全特性基础上,研究了可逆式机组非线性控制策略。首先,建立可逆式机组过渡过程仿真计算平台,为可逆式机组非线性控制规律研究奠定基础。由B样条全特性空间曲面得到水泵水轮机非线性数学模型,再分别建立有压过水系统、发电电动机和执行机构等环节数学模型,由此可得可逆式机组非线性数学模型,然后研究其过渡过程数值计算方法,通过仿真试验验证数值计算方法的可靠性。其次,针对建立的可逆式机组非线性数学模型,运用精确线性化理论得到可逆式机组的非线性控制规律,在可逆式机组仿真计算平台上进行水轮机开机、水泵断电和水泵背靠背启动等大波动工况的仿真试验,结果表明,非线性控制规律相比于线性控制有更好的调节性能。
[Abstract]:Pumped-storage power station has the function of quick response, such as peak filling, frequency modulation and phase adjustment, rotation reserve, etc. In order to solve the problem of peak shaving in power grid, pumped storage power station will be developed vigorously. However, there are two important factors restricting the development of pumped storage power stations in China, one is the description of the full characteristics of pump turbines. The full characteristic description of water pump turbine is the basis of water conservancy design, transient process analysis and control law research. The traditional full characteristic description of pump turbine has the phenomena of opening line aggregation, crossover and torsion, etc. It leads to the difficulty of fitting and the multi-value problem in the calculation of transition process. The second is the efficient and stable operation of pumped storage power station. There are two unstable regions of water pump turbine, namely "S" and hump, which have strong nonlinearity. The traditional control law based on linear theory is not enough to fit the strong nonlinearity of pump turbine. Can not fundamentally to ensure its efficient and stable operation. In order to solve the problems existing in the previous full characteristic description plane representation method, the full characteristic description method of water pump turbine based on the new angle of view of space surface is studied. This new method does not have the phenomena of opening line aggregation, crossover and torsion. Based on the model test data, B-spline theory is applied to construct the full characteristic space surface. The surface characteristic line of the full characteristic space is drawn, which is the basis of the research on the variation law and control law of the full characteristic of the pump turbine. In view of the fact that the linear control theory is not sufficient to meet the needs of the reversible unit in safe and stable operation, the nonlinear control strategy of the reversible unit is studied on the basis of describing the full characteristics of the pump turbine from the view of the space surface. Firstly, a simulation platform of reversible unit transition process is established, which lays a foundation for the study of nonlinear control law of reversible unit. The nonlinear mathematical model of water pump turbine is obtained from B-spline full characteristic space surface, and then the mathematical models of overpressure water system, generator motor and actuator are established respectively, and the nonlinear mathematical model of reversible unit can be obtained. Then, the numerical calculation method of the transition process is studied, and the reliability of the numerical method is verified by simulation experiment. Secondly, according to the nonlinear mathematical model of reversible unit, the nonlinear control law of reversible unit is obtained by using the exact linearization theory, and the turbine is turned on on the platform of simulation and calculation of reversible unit. The simulation results show that the nonlinear control law has better regulating performance than linear control.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TV734.1

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