文档介绍：基于单片机控制的快热式
家用电热水器的设计
摘要
随着人们生活水平的不断提高，单片机控制无疑是人们追求的目标之一，它所给人 带来的方便也是不可否定的，其中家用电热水器就是一个典型的例子。在本设计中采用 单片机AT89C51作为控制器来控制电路。本设计分别对硬、软件进行设计说明。硬件 包括加热控制电路，温度检测电路，LED数码管及指示灯显示电路及报警器驱动电路等 的设计，比如，利用热敏电阻对热水器出口温度进行检测；用温度/频率转换电路通过单 片机的检测间接测出温度值；用单片机通过光耦给可控硅触发信号，控制可控硅的导通 角，而控制电热丝的有效加热功率；用继电器来控制加热电源，使其在关机和超温保护的 状态下可靠的关断；用在继电器线圈回路中串联105°C的熔丝来防止温度过高时加热管 干烧。软件部分给出了部分程序流程图的设计，包括主程序的设计、显示扫描子程序的 设计、按键扫描处理子程序的设计、加热和控制程序流程图的设计、温度检测程序的设 计、频率测试程序的设计。软件编程采用C语言编写，因为其简洁、使用方便灵活、容 易实现程序的模块化和结构化。
关键词：单片机；电热水器；温度/频率转化测温；二分查找法
Design of rapid heating type household electric water heater based on single-chip microcomputer control
Abstract
As people living standard rise ceaselessly, the single-chip microcomputer control is undoubtedly one of the goals of the people to pursue, it brings convenience is not negative, household electric water heater is a typical example of it. In this design uses AT89C51 microcontroller as the controller to control circuit. The design of hardware and software respectively design and explains. Hardware including heating control circuit, temperature detection circuit, LED digital pipe and indicator shows circuit and alarm driver circuit design, for example, using thermal resistance of the water heater outlet temperature testing; Use temperature/frequency conversion circuit is measured by single-chip microcomputer detection indirect temperature; With single-chip microcomputer controlled by light-coupler to trigger signal, Control the conduction angles of the SCR, and control of the resistance wire effective heating power. Use relay to control the heating power, so that the shutdown and over-temperature protection under the condition of reliable shut off; Used in relays coil loop in tandem 105°C melt silk of high temperature to prevent dry heating tube when burnt. Software part gives part of the program flow chart, including the design of main program design, the design of subroutines that display scanning, buttons scanning processing procedure design, heating an