中央空调空气处理系统送风温度控制

发布时间：2018-03-18 20:00

本文选题：表冷器建模　切入点：送风温度　出处：《沈阳工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着科技和社会的进步,人们生活水平的提高,空调系统已被广泛使用。它虽带来了巨大便捷,但在当今能源紧缺的大环境下,带来的能耗问题也不容小觑。空气处理系统是中央空调的一大重要子系统,因此,对空气处理系统的控制研究具有重要意义。本文在阅读大量国内外文献并分析中央空调空气处理系统建模问题和控制问题研究现状的基础上,提出以定风量中央空调空气处理系统的表冷器为研究对象,对表冷器送风温度控制问题进行研究。改进传统表冷器单输入单输出模型,依据能量守恒和质量守恒的基本定律,同时考虑了冷冻水进水温度和冷冻水流量对表冷器送风温度的影响,建立了表冷器动态换热的双输入非线性模型。通过MATLAB仿真对比,该模型能够涵盖传统的单输入单输出模型。分析文中所建立的模型,针对其所具有非线性和可能存在模型参数不确定等问题,提出了两种不同的控制器设计方案。一种是通过设计模糊控制器对表冷器送风温度进行控制,该方法不要求数学模型的精确度,且能够直接用于非线性模型。另一种是引入鲁棒控制方法,将非线性模型在工作点进行线性化处理,形成不确定状态空间模型,将调节问题转化为鲁棒跟踪问题,设计鲁棒控制器,使系统可以克服不确定性带来的影响,保证系统在参数存在一定摄动情况下依旧具有良好的跟踪性能。在MATLAB环境下,对这两种控制系统分别进行仿真研究。通过对模糊控制器的仿真实验,验证了控制器的有效性,该方法控制范围广,具有鲁棒性。通过对鲁棒跟踪控制器的仿真实验,验证了控制器能够克服由模型不确定性引起的影响。在此基础上,提出了采用模糊和鲁棒变换的控制策略,将前文设计的模糊控制器和鲁棒控制器有效结合,使得在控制初期误差比较大时采用模糊控制,当误差比较小时采用基于线性化的鲁棒控制,提高控制效果。
[Abstract]:With the progress of science and technology and the improvement of people's living standard, air conditioning system has been widely used. Although it has brought great convenience, but in today's energy shortage environment, The problem of energy consumption is not to be underestimated. Air treatment system is an important subsystem of central air conditioning. It is of great significance to study the control of air processing system. Based on reading a large number of domestic and foreign literature and analyzing the modeling and control problems of central air conditioning air processing system, Taking the surface cooler of the central air conditioning system with constant air volume as the research object, this paper studies the control of the air supply temperature of the surface cooler, improves the single input and single output model of the traditional surface cooler, and bases on the basic laws of conservation of energy and mass. At the same time, considering the influence of influent temperature and flow rate of chilled water on the air supply temperature of the surface cooler, a double input nonlinear model of the dynamic heat transfer of the surface cooler is established. The simulation results are compared by MATLAB. This model can cover the traditional single input and single output model. Two different design schemes of controller are proposed. One is to control the air temperature of the surface cooler by designing fuzzy controller, which does not require the accuracy of mathematical model. The other is to introduce robust control method to linearize the nonlinear model at the working point to form an uncertain state space model and to transform the adjustment problem into a robust tracking problem. A robust controller is designed to overcome the influence of uncertainty and ensure that the system still has a good tracking performance under the condition of parameter perturbation. The effectiveness of the controller is verified by the simulation experiment of fuzzy controller. The method has a wide control range and robustness. The simulation experiment of the robust tracking controller is carried out. It is proved that the controller can overcome the influence caused by the uncertainty of the model. On this basis, a fuzzy and robust transformation control strategy is proposed to effectively combine the fuzzy controller and the robust controller. The fuzzy control is used when the initial error is large, and the robust control based on linearization is used when the error is small, so that the control effect is improved.
【学位授予单位】：沈阳工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB657.2

【相似文献】