汽轮机的建模与转速控制毕业论文
2021-06-30 20:51:23
摘 要
汽轮机是将蒸汽热能转化为机械能的装置。锅炉将化学能转化为蒸汽的热能并送入汽轮机中,蒸汽进入汽轮机之后,经过高压缸,中、低压缸和转子等一系列装置做功后,推动转子叶片进行转动,最终将蒸汽的热能转化为汽轮机转子旋转的机械能。汽轮机是火力发电,石油化工等国民经济基础产业的重要关键原动机械。
本文首先主要介绍了汽轮机研究的背景及意义;其次了解了国内外研究现状,包括仿真平台、汽轮机本体建模和电液控制系统三个方面,并对对本文的部分参考文献进行简要的介绍。
其次针对300MW凝汽式汽轮,将其划分为不同的模块,分别研究其各个模块的工作原理并建立数学模型。本文采用机理分析法,研究了汽轮机本体各个主要环节的输入与输出物理量之间的关系,推导出了它们的数学微分方程,通过泰勒展开等方法进行线性化,最终得到了各环节的传递函数。有了各环节的数学模型,在MATLAB/SIMULINK中就能够很方便的连接完成汽轮机整体的数学模型。对于执行机构即电液转换器和油动机的模型,本文直接引用了参考文献中的结论。最终形成了汽轮机本体的数学模型。
最后在论文的第三章对模型进行仿真。首先是对第二章所得到的汽轮机各个环节以及汽轮机本模型进行了仿真,得到各个环节的动态特性曲线。其次为了实现对汽轮机系统进行控制,采用了电液控制系统。介绍了数字电液控制系统的组成及工作原理,并用PID串级控制这一控制方案进行了仿真研究。在Simulink中建立了300MW凝汽式汽轮机控制系统的整体仿真模型。然后采用试凑法进行参数整定,通过大量的仿真实验,得到一组较为合理的控制器参数。最后对模型进行验证,能够实现对汽轮机的转速进行控制。
关键词:汽轮机控制;数学模型;仿真研究;数字电液控制系统
Abstract
Turbine equipment is one of the three major thermal power plant equipment in thermal power plants, boiler fuel chemical energy into thermal energy of steam, the steam turbine heat energy into mechanical energy, power plants will shaft mechanical energy into electrical energy. Since the steam turbine having a single power, high efficiency, smooth operation, low power unit manufacturing costs and long service life, etc., so it has been one of the most important equipment in a modern country in mechanical power .
This paper introduces the research background and significance of the turbine at first; Secondly introduce the research status at home and abroad, including three simulation platform, Steam Turbine Modeling and electro-hydraulic control system, and incorporated herein by reference for some brief introduction.
Secondly, the mathematical model of the major components of 300MW condensing steam turbine generator control system had been established. In this paper, the mechanism analysis method has been used to study the relationship of the input and output between the main part such as electro-hydraulic converter control system,, the intake volume of steam power, the main rotor and other aspects of the physical and deduced their mathematical equations, then linearize them through Taylor expand methods, and ultimately by the various aspects of the transfer function. With mathematical models of every parts,in the MATLAB / SIMULINK,it will be able to easily connect the turbine to complete the overall mathematical model. Namely, electro-hydraulic actuator for the converter and the oil motive model, this paper directly references cited conclusions. Eventually forming a mathematical model of the turbine body.
Finally, in the third chapter of the model simulation. The first is the second chapter of the resulting steam turbine and steam turbine present in all aspects of the model simulation, the dynamic characteristic curve obtained all aspects. Secondly, in order to achieve the turbine control system, using electro-hydraulic control system. After introducing the steam turbine digital electro-hydraulic control system on the structure and function of cascade PID control scheme based on the turbine control system is widely used in the simulation study comprehensive and detailed. And the establishment of the overall simulation in Simulink model 300MW condensing steam turbine control system, using trial and error, through a large number of simulation experiments, to obtain a more reasonable set of controller parameters.
Keywords:steam turbine control;mathematical modeling;simulation research.