【作者】 张丽丽；

【导师】 高晓阳；

【作者基本信息】 甘肃农业大学 ， 农业机械化工程， 2008， 硕士

【摘要】 干燥是啤酒大麦麦芽处理的一个重要环节,为便于麦芽储存和运输,必须降低其含水率。传统大麦麦芽干燥过程都是人工操作,而且干燥室结构简单,干燥过程是非线性、时变性和多变量的耦合过程,难于建立精确数学模型。大量资料显示,自适应、自校正控制理论可以对缺乏数学模型的被控对象进行识别,但这种递推法复杂,实时性差,对大麦麦芽水分的控制难以取得较好的控制效果,而且耗能大。相比较而言,将模糊控制应用于大麦麦芽干燥控制系统,成为最佳选择。本文将模糊控制理论最新应用于大麦麦芽干燥控制系统。对本系统被控量温度设计了模糊控制器。将计算机控制过程得到的精确量转化为模糊输入信息,按照总结人的控制经验及策略取得的语言控制规则进行模糊推理和模糊决策,求得输出控制量的模糊集,经模糊判决得出输出控制精确量,作用于被控对象,即可在控制过程中取得良好的控制效果。硬件部分设计是结合大麦麦芽干燥室实际情况,采用AT89C51为核心的单片机控制系统。检测部分由温度采集及调理电路和湿度采集及调理电路组成,均输出模拟量的电压信号。再经大规模集成电路芯片ADC0809输出8位数字量信号传给单片机。单片机通过P1.1,P1.2口控制电磁继电器,从而控制抽风机的开闭;通过P1.3～P1.6口控制变频器从而改变鼓风机的转速。本系统中其它外围电路包括键盘与显示、报警及人工复位电路。软件部分设计主要是采用汇编语言进行编程。本系统包括1个主程序,6个子程序,其中子程序有数据采集存储子程序、平均滤波子程序、模糊控制子程序、温湿度显示子程序、键盘扫描子程序、及报警子程序等。本系统控制的参数主要是温度和湿度,控制过程中温度采用模糊控制,模糊控制器的MATLAB仿真部分充分利用MATLAB模糊逻辑工具箱功能,结合图形化系统建模和仿真工具,通过计算机仿真模拟出系统实际输出情况。最终,本设计建立了先进、稳定、高效的整体系统。温度控制范围达0～100℃,控制精度达到±0.2℃。湿度控制范围达1%～99%RH。实现干燥过程的智能化控制,并大大缩短干燥时间,节能效果非常显著。更多还原

【Abstract】 Drying is an important step during beer barley malt processing. In order to good storage and transport, it is necessary to reduce the barley malt’s moisture content. The traditional barley malt drying process is manual, the structure of the drier is simple,and the drying process are non-linear ,changing with the time and mufti-variable. So it is hard to establish the precision of the mathematic model. A great deal of information Showing that the theory can recognize the controlled object which short of the mathematic model, and it is hard to get useful control effect because of the complication and the disadvantage in the real- time control. Comparatively speaking, it is the best choice that applied fuzzy-control to barley malt drying control system.This article of barley malt drying control system established fuzzy-control theory first. Design of a fuzzy controller on temperature which is controlled of system. The accuracy quantum which is get from Computer-controlled process will be change into fuzzy information, According to the control experiences and strategies, we can get the language control rules which is proceed fuzzy inference and fuzzy decision- making, get fuzzy sets of output control. Get precise quantum of control by fuzzy judgement that act on the control object. You can receive good control results in control process.The part of the hardware design is combine the actual situation of Barley malt drying room, use AT89C51 as the core of the SCM Control System. The part of detection include acquisition and processing circuit of temperature and acquisition and processing circuit of humidity, which output are all voltage signal. Eight digital signals of A/D transmission to SCM. SCM through P1.1, P1.2 that control electroma- gnetic relay and thus control the opening and closing exhaust Fan. SCM through P1.3 ~ P1.6 that control the frequency converter to change the speed of blower. The system in other external circuit, including keyboard and display, alarm and manual reset circuit.The system used assembly language as programming language. The system includes a main program, six subprogram. The main of subprogram are data collection and storage, average filtering, fuzzy-control, temperature and humidity display, keyboard scanning, and alarm etc.The main parameters of the design control system are temperature and humidity, using fuzzy-control during the temperature control process, and taking full advantage of fuzzy-logic toolbox in MATLAB, with graphical system modeling and simulation tools, simulating the factual situation of outputing through PC. Finally, The system is established an advanced, stable, and efficient control system. Humidity control can up to 1% ~ 99% RH. Temperature control can up to 0 ~ 100℃, temperature control accuracy can reach to±0.2℃.It is achieved intelligent control in process of drying,and greatly shorten the drying time, and energy-saving effect is very significant.更多还原