【作者】 朱泽磊；

【导师】 韩忠旭； 黄焕袍；

【作者基本信息】 中国电力科学研究院 ， 电力系统及其自动化， 2010， 硕士

【摘要】 电力系统已进入大机组大电网时代,对机组控制和机网协调的要求越来越高。现代火力发电机组,特别是大容量、高参数机组,其复杂程度越来越高,AGC在应用过程中遇到的难点问题,是大容量单元制火力发电机组存在着较大的滞后和惯性,因此负荷响应速率受到限制。建立机组准确的数学模型,有效的克服机组迟滞和大惯性,能提升电站控制系统的控制品质。本文将双线性拟合应用到单元机组协调控制系统中。将复杂二元函数拟合为双线性结构,更加准确的描述变量间的强耦合关系。通过将回热系统纳入到机组热平衡所进行的数学分析,在汽包炉单元机组全局热平衡的物理概念下,研究并给出一种新型的考虑回热影响的汽包炉单元机组实用仿真数学模型。并融合多种控制理念,研究并设计了一种广义智能控制系统,采用状态空间法统一描述闭环控制系统,由数学分析给出了系统稳定的充分条件及其稳定性证明。借助机炉协调受控对象数学模型,提出模拟柔性模糊预给煤控制的概念,并对算法通过仿真和在实际机组中的实验加以验证。该算法实现过程简捷,可直接在计算机控制系统中运用各种现有的算法实现,不依赖于专有的模糊控制算法模块,有利于工程应用。应用该算法可以克服锅炉的大迟滞和大惯性,能够有效地提高协调控制系统响应AGC负荷指令的速率。在非线性单元机组数学模型的基础之上,结合双线性拟合等数学方法及模拟柔性模糊控制等各种智能控制的概念方法,对电站控制系统进行优化改进,提高其控制品质,进而研究了大机组的建模控制特性以及其对现代电网的影响.为研究发电机组在电力系统中长期动态仿真的特性,本文给出了用于电力系统中长期动态仿真的广义调速器模型,分析研究了应用广义调速器模型的电力系统中长期动态响应特性。通过自定义建模的方法,将单元机组数学模型及其相应的控制系统纳入到仿真环境中,从一次调频、机炉协调和功频调速等控制机理方面进行仿真研究,研究防止和抑制电力系统低频振荡的方法与措施。更多还原

【Abstract】 Power system has entered the era of large power grids and large unit, the unit control and coordination between unit and grid have become increasingly demanding. Modern thermal power generating units, especially in high-capacity, high parameter, the unit complexity is increasing. The difficulty in applying AGC to project lies in large lag and inertia for large capacity unit power, load respond is limited. The establishment of the accurate mathematical model of a unit effectively overcome the large lag and large inertia, then enhance the control quality of power plant control system.Bilinear fitting applied to the unit coordinated control system, complex binary function was fit as a bilinear structure that more accurate described the strong coupling relationship between the variables. the mathematical analysis was carried out by the regenerator system integrated into heat balance of generator unit. Under the physical concept of the global heat balance of drum-boiler turbine generator unit, a new type of simulation mathematical model for drum-boiler turbine generator unit with regenerator system was researched. Fussing multiple thinking modes of intelligent control, to research and design a generalized intelligent control system, which is fully described by state space method. The system steady sufficiency conditions and its stability proving are presented.With mathematical model of boiler-turbine coordinated control object, the concept of analogy flexible fuzzy control is introduced. And the algorithm has been proved by simulation test and practical process. This algorithm is easy to be realized in project by applying all sots of existing algorithms in computer system not depending of special fuzzy control module. Not only it, but also this algorithm can overcome the large lag and inertia for boiler and heightening the responding rate to AGC in boiler-turbine coordinated control system in effect and reheated temperature control characteristic.Based on non-linear mathematical model of unit, combined with bilinear fitting mathematical methods, analogy flexible fuzzy control concept and other intelligent control methods, power plant control system was improved and its quality control was enhanced. Then, the modeling features of control system for a large unit and its iMPact on modern power grid were studied. In order to study the long-term dynamic characteristic of generator in power system, it is presented a generalized speed governor model used in long-term dynamic simulation. The dynamic response characteristics of generalized speed governor model used in long-term dynamic simulation were analyzed. According to the characteristics of contemporary thermal power equipment, through the custom modeling method, and taking the unit mathematical model and its control systems into the simulation environment, primary frequency, boiler-turbine coordinated and power-frequency speed governor control mechanism are taken into simulation system to further explore the deep-seated reasons that caused the turbine pressure pulsation.更多还原