基于系统动力学的电站磨煤机建模与控制

发布时间：2018-04-26 23:22

本文选题：中速磨煤机 + 系统动力学　；参考：《华北电力大学》2017年硕士论文

【摘要】：我国“富煤、贫油、少气”的能源特点决定了未来一段时间我国电力能源仍然主要依靠燃煤火力发电。随着我国火电站装机容量的不断增大,中速磨煤机直吹式制粉系统在电站中的应用越来越广泛。作为主要的制粉设备,中速磨煤机运行的安全性和经济性直接影响着电站锅炉的安全性和经济性。因此,对中速磨煤机进行建模与控制研究具有实际意义。本文从物质和能量传递角度出发来分析中速磨煤机的运行机理,并基于系统动力学原理,建立能反映中速磨煤机系统内部变量因果关系的因果回路图和能反映内部变量定量数学关系的存量流量图。然后,在系统动力学仿真软件Anylogic中对所建模型进行仿真分析,并将仿真结果和传统微分方程模型的仿真结果进行对比。针对所建系统动力学模型,采用冷一次风阀门开度调节磨煤机出口温度、热一次风阀门开度调节一次风流量的控制方案,并选用传统的PID控制器对中速磨煤机进行控制。结合工程整定法整定控制器的参数,实现对磨煤机出口温度和一次风量的控制。鉴于在系统参数辨识、参数优化等领域有着广泛应用的果蝇优化算法所具有的计算量小、原理简单、收敛性好等特点,为了克服本文设计的磨煤机控制系统存在的调节时间过长、超调量偏大等问题,采用果蝇优化算法对控制器参数进行了优化。将优化前后控制器对中速磨煤机系统的控制效果进行了对比分析,结果表明经过果蝇优化算法优化后的控制器对中速磨煤机具有更好的控制效果。针对磨煤机大惯性和大延迟的特性,结合模糊控制理论,在优化后的控制器基础上,设计了自整定模糊PID控制器。并将自整定模糊PID控制器和果蝇优化算法优化前后的控制器的控制效果进行对比,验证了所设计的自整定模糊PID控制器对系统具有良好的控制效果。
[Abstract]:The energy characteristics of China's "rich coal, poor oil and low gas" determine that the power energy of China is still mainly dependent on coal-fired power generation for a period of time. With the increasing installed capacity of China's thermal power station, the application of direct pulverizing system of medium speed pulverizer is becoming more and more extensive in the power station. As the main pulverizing equipment, the medium speed mill is transported. The safety and economy of the line directly affect the safety and economy of the power plant boiler. Therefore, it is of practical significance to study the modeling and control of the medium speed pulverizer. This paper analyzes the operating mechanism of the medium speed pulverizer from the point of material and energy transfer, and establishes a medium speed pulverizer system based on the principle of system dynamic mechanics. The causality loop diagram of the internal variable causality and the stock flow diagram that can reflect the quantitative mathematical relationship of the internal variables. Then, the model is simulated and analyzed in the system dynamics simulation software Anylogic, and the simulation results are compared with the simulation results of the traditional differential equation model. The opening of the cold air valve adjusts the outlet temperature of the coal pulverizer, and the control scheme of the first air flow is controlled by the opening of the first air valve, and the traditional PID controller is used to control the medium speed pulverizer. The control of the temperature and the first air volume of the pulverizer is realized with the parameters of the whole setting method. The optimization algorithm of fruit fly has the characteristics of small calculation, simple principle, good convergence and so on. In order to overcome the problems of long adjustment time and overshoot of the coal mill control system designed in this paper, the optimization algorithm of fruit fly is used to optimize the controller parameters. The control effect of the controller to the medium speed pulverizer is compared and analyzed. The results show that the controller has better control effect on the medium speed pulverizer after the optimization of the fruit fly optimization algorithm. Based on the fuzzy control theory, the self-tuning model is designed on the basis of the optimized controller. The control effect of the self tuning fuzzy PID controller before and after the optimization of the optimization algorithm of the Drosophila fly is compared. It is verified that the designed self tuning fuzzy PID controller has good control effect on the system.

【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP273;TM621

【参考文献】