摘 要
电冰箱作为应用较为普及的家用电器，近年来，随着微电子技术、
传感器技术以及控制理论的发展，电冰箱具有温度模糊控制、智能化霜、故障自诊功能，同时还具有控制精度高、性能可靠、省电等优点，并能达到高质量食品保鲜的目的，是电冰箱发展的主要方向。
电冰箱控制的主要任务就是保持箱内食品最佳温度，达到食品保鲜的目的。由于冰箱内温度受多种不确定因素影响，如放入冰箱中物品的温度、热容量以及物品的充满率、开门的频繁程度等，冰箱内的温度场的数学模型很难建立，因此无法用传统的控制方法实现精确控制。 本文采用模糊控制技术可以方便地提高控制精度，配以电子温度检测，对压缩机的工作状态进行调节，达到精确控温和节能的目的。通过变频控制可以使冷冻室的温度控制更加合理。当冷冻室需要制冷量比较大的时候，可以通过变频调控，使电机高速转动，就加强压缩机制冷；同理，当冷冻室制冷量比较小时，则使电机转速慢一些。就降低压缩机制冷。通过半导体制冷使冷藏室的温度控制更加精确。在冷藏室需要制冷的时候可以启动半导体制冷，而不用启动压缩机，这样一方面避免了压缩机的频繁开启，另一方面也节约了能量，同时也保证了冷藏室的温度更加准确。
为了提高冰箱的性能，软件上还采取了自学习功能、故障运行自恢复功能、维护自检功能和容错技术等抗干扰设计。该系统具有控制精度高、性能可靠、省电等特点。
关键词：模糊控制论；冰箱；单片处理机；自学习
Abstract
In recent years, refrigerator as a widespread family electronics, they orientation of developing refrigerators.
The control of the refrigerator aims to keep the food furthest temperature. But there are many factors effect the refrigerator temperature, such as food temperature, thermal capacity, full or not and frequency of opening door. So it's difficult of building the model of the refrigerator. So it can't realize precision control using traditional control method.
The Paper improves the control precision utilizing fuzzy control technology. And the frequency conversion designed in order to avoid starting up compressor frequently which makes the electrical machinery work according to requirement. So the refrigeration of compressor will be more effective. Safe adopts the semiconductor and compressor to refrigerate at the same time. In the normal situation the safe refrigerates with refrigeration of the freezer when the freezer needs refrigeration, the system starts the mechanism of compressing. The safe can reach the
refrigeration result at the same time. When the freezer does not need refrigeration, the semiconductor will be used alone-The result controlled like this can make the safe achieve the goal of controlling alone basically. For the performance of refrigerator ,the self-learning, self-repairing, self-checking and fault tolerant technique ale used in software designing, This system reliable performance and saving electric energy.
Keywords：Fuzzy control theory; Refrigerator; Single chip compute; Self-learning
目 录
1 绪论 ·········································································································· 1
1.1课题背景及意义 ················································································ 1 1.2智能冰箱系统概述 ············································································ 1 1.3 方案论证 ························································································· 2 2 系统介绍 ··································································································· 3
2.1概述 ································································································· 3
2.1.1电冰箱的热负荷 ······································································ 3 2.1.2 电冰箱的系统结构 ·································································· 4 2.2 系统设计与功能简介 ········································································ 4 3 系统数学模型与控制理论 ··········································································· 7
3.1概述 ································································································· 7 3.2模糊智能控制理论 ············································································ 7
3.2.1 模糊智能控制的发展 ······························································ 7 3.2.2 智能模糊控制的基本原理 ························································ 8 3.2.3 模糊控制算法 ········································································ 11
3.2.4模糊智能控制在电冰箱系统中的实现 ······································ 18 3.2.5 模糊控制应用于冰箱上的必要性、可行性 ······························ 19 4.1智能冰箱的功能 ··············································································· 20 4.2冷冻室制冷的实现方法 ···································································· 21 4.3冷藏室制冷的实现方法 ···································································· 22 4.4模糊化霜的实现 ··············································································· 24 5 硬件系统 ·································································································· 25
5.1系统概述 ························································································· 25 5.2系统电路设计 ·················································································· 28
5.2.1按键输入的实现 ····································································· 28 5.2.2蜂鸣的实现 ············································································ 28 5.2.3温度采集的实现 ····································································· 29 5.2.4 显示电路的实现 ···································································· 30 5.2.5变频调速的实现 ····································································· 31
6系统软件 ··································································································· 34
6.1系统软件概述 ·················································································· 35 6.2 件总体结构 ····················································································· 35 7 结 论 ······································································································· 36 致 谢 ·········································································································· 37 参考文献 ····································································································· 38
1 绪论
1.1课题背景及意义
众所周知，电冰箱是现代家庭中必不可少的家用电器。而目前市售冰箱大多采用传统的机械式温控，控制精度差，功能单一，控制方式简单难以满足现代冰箱发展的要求。
随着经济的发展和人民生活水平的进一步提高，人们对多功能化的发展要求越来越高。单片机技术和电子技术的高速发展，使得箱内温度控制可随冷藏室和冷冻室的不同而分别设定，定时自动除霜、白动制冰、省电等诸多功能和要求得以实现。特别是模糊控制技术在家用电器中的应用日趋成熟，为电冰箱向智能化方向发展提供了有利技术支持[1]。
在电冰箱的控制中，温度是主要的控制对象，控制的好就有显著的节能效果。但冰箱内要受诸如环境温度的高低、冰箱本身的容积、冰箱中食物的多少、以及食物的种类和性质、存放物品的初始温度、散热特性及其热容量、物品的充满率及开门的频繁程度等控制。冰箱内的温度场分布极不均匀，要想建立电冰箱温度变化的精确数学模型是很困难的，因此采用模糊控制技术才能达到最佳的控制效果[2]。
1.2智能冰箱系统概述
智能控制技术的发展，正在改变着人们的生活方式，更加舒适、更加可靠的家用电器可日益提高人们的生活水平。单片机是智能家电的核心单元，因为单片机是嵌入在家用电器中，没有自己独立的外壳，通常称为嵌入式系统，如今嵌
入式系统无处不在，正推动着二十一世纪一场新的产业革命。为了适应智能控制
技术的发展，单片机在它诞生以来的二十多年内，发生了迅猛的变化，从