基于单片机的节水灌溉自动控制系统设计

本科生毕业设计

摘要

自动控制节水灌溉技术代表了农业现代化的发展状况，灌溉系统自动化水平比较低下是制约我国高效农业发展的主要原因。本文就此问题研究了基于单片机的节水灌溉自动控制系统，系统对土壤湿度进行监控，并按照农作物的要求进行适时适量的灌水，其核心部分是单片机控制部分，主要对灌溉控制技术以及系统的硬件设计，软件编程各个部分进行深入的研究。

控制部分以单片机为核心，研制了一种基于单片机的节水灌溉自动控制系统。介绍了系统总体结构、单片机系统主机电路、数据采集处理电路、I/O口的扩展电路。为了进行大规模灌溉工程的监控，采用分布式控制模式，以提高控制系统的可靠性、降低系统的成本。

该套基于单片机控制的节水灌溉自动控制系统造成本低，体积小、安装方便、抗干扰性强、运行可靠，相比其他控制方式来说，性价比高，更易形成产品，便于推广应用。这是我国灌溉自动控制技术的一种新尝试，为目前农业在较低生产力水平的状况下，向智能化、市场化方向发展开辟了一条新途径。

关键词： AT89C51单片机；湿度传感器；A/D转换；采样；芯片

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本科生毕业设计

ABSTRACT

The level of auto-control water-saving irrigation technology reflects the development condition of agriculture modernization.The low automatic level of irrigation system is the main reason that prevented our agriculture’s development.As to this condition,this paper mainly studies the water-saving irrigation system that controlled by MCU.This system can supervise humidity.it can irrigate to the demand of the farm crops with right amunt of water at well time.The control part that consists of MCU is its core.Research work had been carried on irrigation control technology,hardware and software program and so .

The control that consists of MCU is its core.A set of automatic water-saving system which is controlled by sing-chip controller have been developed in this paper.The overall structure of system、the main circuit of the MCU system、data-collecting circuit、I/O expanding circuit are all the designed.For monitoring large-scale irrigation system,we use distributional control model to enhance stability of the system de reduce the cost.

It is small,easy to fit,a strong capability to resist interfere and low-cost.So the control system is more economic compared to other control system such as thuter system and all these demonstrate this production is adept to be popularized.This work is a fresh attempt to bring our agriculture into an advanced stage,which now is relative to be backward greenhouse control technique,especially on the aspect of nutrient liquid supplying when crops cultivated on tissue.

Key words: AT89C51 MCU; Humidity Sensor; A/D transform; Sampling; Chip

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本科生毕业设计

目录

摘要 (Ⅰ)

Abstract (Ⅱ)

第1章绪论···························································································错误！未定义书签。

1.1引言····································································································错误！未定义书签。

1.2 选题背景及研究的目的与意义···················································错误！未定义书签。

1.2.1 选题背景 ··············································································错误！未定义书签。

1.2.2 研究的目的与意义·····························································错误！未定义书签。

1.3 研究内容 ··························································································错误！未定义书签。

1.4 节水灌溉控制系统国内外的研究现状及存在问题 ················错误！未定义书签。第2章灌溉系统总体设计方案 ·······················································错误！未定义书签。

2.1 计算机控制系统的基本形式 ·······················································错误！未定义书签。

2.2 系统总体方案 (7)

2.2.1 AT89C51微控器构成的最小系统 (8)

2.2.2 数据采集部分 (8)

2.2.3 显示部分 (9)

2.2.4 供电电源单元 (9)

2.3 本章小结 ··························································································错误！未定义书签。第3章系统硬件电路设计 ·································································错误！未定义书签。

3.1 本系统的硬件设计概述 ································································错误！未定义书签。

3.2 单片机的选择及分析 (11)

3.2.1 单片机的定义和特点 (11)

3.2.2 单片机的发展概况·····························································错误！未定义书签。

3.2.3 本系统单片机的选择 (12)

3.3 本系统硬件电路部分 (16)

3.3.1 系统的工作原理 (16)

3.3.2 单片机主系统电路 (17)

3.3.3 时钟电路 (17)

3.3.4 数据存储的扩展电路 (18)

3.3.5 数据采集处理电路 (19)

3.3.6 LED显示电路 (20)

3.4 电磁离合器异步电动机 (21)

3.4.1 电机概念介绍 (21)

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