【作者】 高慧敏；

【导师】 刘宪林；

【作者基本信息】 郑州大学 ， 电力系统及其自动化， 2003， 硕士

【摘要】 随着大型水电站和抽水蓄能电站的不断兴建和投入运行，水电在我国电力系统中的比重逐年增大，水电系统的稳定性问题日益突出，同时也对水电系统仿真提出了更高的要求。电力系统仿真往往采用粗略的输水系统—水轮机模型，而水力系统仿真则往往采用粗略的同步电机—电力系统模型。采用这种水或电的单方面简化模型不能准确反映水力系统与电力系统的耦合作用，对于诸如电力系统中长期稳定、水轮发电机组再同步、调压井系统大波动稳定等这些与水电耦合和自动调节作用密切相关的问题的研究，可能导致不合理的结论。因此，开展学科交叉研究，建立合理的水电系统详细模型，研究水电系统大扰动过程的仿真算法，对于弥补我国电力系统仿真计算中存在的输水系统—水轮机模型过于粗略的不足，提高水电系统仿真水平，是非常必要的。 鉴于电力系统研究中输水系统和水轮机模型过于简单的情况，本文首先归纳引入了复杂输水系统和水轮机的详细模型，建立了适合大扰动动态过程计算的水电系统详细数学模型，包括基于特征线法的复杂输水系统自动建模模型、混流式水轮机的线性模型和非线性模型、调压井通用模型、同步发电机模型、调速器模型、励磁系统模型和电网模型等。复杂输水系统的自动建模对于电力系统研究者而言是非常重要的，本文建立的输水系统自动建模模型包括输水系统各种典型单元的数学描述，计及了弹性水击的影响和复杂管道之间的耦合作用，可以适应输水系统结构的复杂多样性，具有较高的精度和建模效率。归纳介绍了混流式水轮机的模型，包括基于模型综合特性曲线的线性化模型、基于内特性描述的线性化模型、基于全特性曲线的非线性模型和简单解析非线性模型等，对这些水轮机模型进行分析比较，认为它们的特点各有不同，应根据研究目的和已知条件来选择合适的模型。 计及弹性水击后，水力系统模型和电力系统模型的形式有很大的差异，水力系统模型含有偏微分方程组，而电力系统模型为常微分方程组。直接将与这两种模型对应的差分方程联立求解有一定难度，即如果直接联立求解，要求差分方程的数目固定，这将不利于复杂输水系统的自动建模。为解决这一问题，本文提出了一种将水力系统和电力系统方程交替求解的水电系统联合仿真算法，即将包括输水系统、水轮机以及机组转子等部分的水力系统差分方程作为一部分，将包括同步发电机、励磁系统以及电网等部分的电力系统微分方程或差分方程作为另一郑州大学工学硕士论文部分，对前一部分采用特征线法求解，对后一部分根据模型形式采用龙格一库塔法或隐式积分法等算法求解，这两部分的求解过程交替进行，最终即可得到水电系统大扰动过程的仿真结果。这种水电系统联合仿真算法，既可满足各种复杂输水系统自动建模的要求，又能提高计算速度，保证计算精度，计算程序也简单明了，易为水电两个专业的研究者接受。 采用C++ Bullder可视化语言，编制了独立的复杂输水系统一简单电力系统大扰动过程仿真软件。采用Visua1C十十可视化语言编制了采用复杂输水系统弹性水击模型和水轮机详细模型的水力系统动态仿真用户程序，通过中国电力科学研究院PSASP程序提供的用户程序接口，与PASASP程序联合实现了复杂水电系统大扰动过程的仿真计算。采用两个程序对上述两种不同的水电系统分别进行大扰动过程仿真计算，取得了合理可信的结果，表明了水电系统详细模型和联合仿真算法的正确性。更多还原

【Abstract】 With the building and operating of large-scale hydro power stations and pumped storage plants, the proportion of water power to power system is increasing year by year in china and the stabilization problem of hydro-electrical system is standing out, which bring forward higher requirement to the united simulation of hydro-electrical system. The transient simulation of power system uses usually simplified models of conduit system and hydro turbine. Similarly the simplified models of synchronous generator and power system are used in transient simulation of hydraulic system. The oversimplified models can not reflect the mutual effect of hydraulic system and power system, and they may cause irrational conclusions when they are used in the studies on middle or long term stability, resynchronization of hydro turbine and generator and large-disturbance surge tank system that relate closely to the mutual effect of hydraulic system and power system or the auto governing. Consequently in order to make up the faults that hydro turbine models are single and simply and models of complex conduit system are scarce, it is necessary that the detail models of hydro-electrical system be established to make crossed study of different subjects and the simulation arithmetic of the large-disturbance transient be studied.On account that models of conduit system and hydro turbine are oversimplified, first of all the detail models of complex conduit system and hydro turbine are summed up, and then the detail models of hydraulic system and power system which are fit for the large disturbance transient calculation are established, including auto modeling models of complex conduit system based on the characteristic equations, linear and nonlinear models of Francies’ hydro turbine, surge tank’s current model and generator’s model, governor’s model, excitation system’s model and grids’ model in the thesis. The auto modeling of complex conduit system is very important for the researchers of power system. In the thesis the conduit auto modeling models consist of the mathematic descriptions of a variety of typical units and take account of the effect of elastic hammer and mutual action of complex conduits, which can adapt to the complexity of the construction of conduit system and have high precision and efficiency. The Francies’ hydro turbine models are induced, comprising of the linear model based on the model characteristic curves, the linear model based on the internal characteristics description, the nonlinear model based on four-quadrant characteristics and simply analytic nonlinear model. As a result of comparison of these models, it is believed that these models have different traits and the proper model should be selected according to the study purpose and known conditions.The equation’s forms of the hydraulic system models with elastic hammer havegreat difference from power system models that hydraulic system models have partial-differential equations while the power system models all are constant-coefficient differential equations. Because directly resolving equations requires constant equation number, it is difficult that the equations corresponding to two models are directly combined together to resolve, which isn’t to the good for the auto modeling of complex conduit system. In order to resolve the question, in the thesis a simulation arithmetic of hydro-electrical system is put up. The equations of hydro-electrical system are divided to two parts, one of which consists of the differential equations of conduit system, hydro turbine and generator’s rotator and is solved by characteristic equation arithmetic, the other of which consists of the differential equations of generator, magnetic system and grid and is solved by longge-kuta arithmetic or covert integrated arithmetic. Through the alternative solving of the two parts, the simulation results of the large-disturbance transient could be abstained eventually. The simulation arithmetic of hydro-electrical system can meet the requirement of auto modeling of complex cond更多还原