直流锅炉主蒸汽温度控制系统研究

发布时间：2018-07-04 18:40

本文选题：锅炉蒸汽系统 + 串级PID控制　；参考：《西安建筑科技大学》2017年硕士论文

【摘要】：火力发电是现代社会电力发展的主力军,随着现代科学技术的不断进步,电厂发电机组的容量增大,参数提高,系统变得更加复杂。在建设和谐社会、发展循环经济的大背景下,对于提高火电厂自动化水平以及机组的经济运行提出了新的要求。而锅炉蒸汽控制系统作为火电厂生产过程中重要的系统之一,蒸汽参数直接影响着机组的安全生产以及经济运行。其中主蒸汽温度是主要的控制参数,提高其自动化控制水平、优化其控制策略就显得尤为迫切。本文以主蒸汽温度为研究对象,针对其延迟大、惯性大、时变和非线性的性质,对主蒸汽温度控制系统进行了研究与实现,并完成了仿真实验研究,主要研究工作如下:(1)介绍了主蒸汽温度对系统的影响,对主蒸汽温度在外界扰动因素影响下的动态特性以及静态特性进行了深入分析,给出了主蒸汽温度的数学模型,并详细阐述了基于喷水减温控制手段的串级主蒸汽温度控制策略。(2)在对模糊控制以及PID算法进行研究的基础上,根据模糊控制系统不依赖于被控对象的精确数学模型的性质,将传统串级PID控制系统中的PID主调节器以模糊PID控制器代替,设计模糊PID主蒸汽温度控制系统,对系统的工作原理及实现过程进行了研究。(3)结合神经网络与模糊系统,将模糊逻辑技术置入神经网络,利用神经网络结构来实现模糊逻辑推理,使系统同时体现专家知识的语言规则以及神经网络的自学习能力,设计基于模糊神经网络得主蒸汽温度控制系统,对系统的工作原理及实现过程进行了研究。(4)仿真实验研究,采用MATLAB对模糊PID算法及模糊神经网络算法进行仿真,结果表明以模糊PID控制代替PID控制,可以提高控制系统对主蒸汽温度的调节品质;而基于模糊神经网络的主蒸汽温度控制系统的控制效果则更加高效。
[Abstract]:Thermal power generation is the main force of power development in modern society. With the development of modern science and technology, the capacity and parameters of generating units in power plants increase and the system becomes more complex. Under the background of constructing harmonious society and developing circular economy, new requirements are put forward for improving automation level of thermal power plant and economic operation of unit. Boiler steam control system is one of the most important systems in the production process of thermal power plant. Steam parameters directly affect the safe production and economic operation of the unit. The main steam temperature is the main control parameter, so it is urgent to improve the automatic control level and optimize the control strategy. In this paper, the main steam temperature control system is studied and implemented in view of its large delay, large inertia, time-varying and nonlinear, and the simulation experiment is completed. The main research works are as follows: (1) the influence of the main steam temperature on the system is introduced. The dynamic and static characteristics of the main steam temperature under the influence of external disturbance factors are deeply analyzed, and the mathematical model of the main steam temperature is given. The temperature control strategy of cascade main steam based on the method of reducing temperature by spraying water is described in detail. (2) on the basis of the research of fuzzy control and pid algorithm, according to the properties of the fuzzy control system which does not depend on the precise mathematical model of the controlled object, The main pid controller in the traditional cascade pid control system is replaced by the fuzzy pid controller, and the fuzzy pid main steam temperature control system is designed. The working principle and realization process of the system are studied. (3) combining the neural network with the fuzzy system, The fuzzy logic technology is put into the neural network, and the neural network structure is used to realize the fuzzy logic reasoning, which makes the system embody the language rules of expert knowledge and the self-learning ability of the neural network at the same time. A steam temperature control system based on fuzzy neural network is designed. The working principle and realization process of the system are studied. (4) the simulation experiment is carried out, and the fuzzy pid algorithm and fuzzy neural network algorithm are simulated by MATLAB. The results show that the quality of the control system can be improved by replacing pid control with fuzzy pid control, and the control effect of the main steam temperature control system based on fuzzy neural network is more efficient.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP273;TM621

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