基于单片机的温度控制系统的硬件设计 摘 要本文针对温度控制的特点，提出了单片机温度控制系统的硬件设计方法，同时也对温度控制系统的控制过程做了理论分析，建立了控制系统的数学模型提出了克服温度控制系统中纯滞后影响的控制方法。该单片机温度控制系统由键盘、AD 采样、PWM 控制与显示四部分构成。其中，键盘输入给定温度值；由 AD574 将采集的温度转换为数字量送入单片机；通过 PWM 控制调节脉冲的宽度，从而获得所需要的输入与输出电压；最后由LED 显示给定温度与检测温度值。温度控制系统普遍存在大延时、纯滞后的特性，常引起系统产生超调和震荡，使控制系统的稳定性降低。因此，本设计采纳史密斯预估器对系统进行纯滞后补偿，以此消除系统的超调和震荡，使系统稳定。文中给出了控制系统的数学模型，确定了系统控制方案和控制系统的硬件电路框图，本设计可直接应用于工业控制中。本设计通过 PROTEUS 软件对系统的硬件进行仿真，通过 MATLAB/SIMULINK的仿真结果验证数字控制器设计的正确性。关键词：温度控制，单片机，纯滞后，史密斯预估器The hardware design in temperature control system based on MicrocontrollerAbstractThis article narrates the hardware design in temperature control system. Aiming at temperature control problem which industry produce usually occurs. We can use the software and the hardware source of the single chip microcomputer (AT89C51) to check, control and display the temperature value on real-time. The settle temperature value is input by the keyboard. Here we make the system to follow this settle value,and finally to attain the purpose of automatic control.This temperature control system is mostly made of four parts which consists of the keyboard,AD sampling circuit, PWM control and LED real time display part.Among of them,keyboard inputs the settle value.AD574 transforms the temperature into digital signal and sends it into single chip microcomputer.PWM control circuit regulates the width of pulse in order to attain input and output voltage that needed.At las...
