【摘要】 为满足理工科学生热电偶实验需要,研制了一种热电偶实验系统。该系统采用MSP430F149作为主控制器,通过铂电阻实现高温端和低温端的温度测量,使用仪表放大器AD620实现热电偶电动势的微弱信号放大,利用主控制器内部ADC12实现微弱信号的采集。利用数字滤波技术对干扰信号滤波,用线性插值法求解温度值,最后用PWM信号实现对PTC和风扇的控制,达到设定温度和高温端的温度差在0.2℃以内。采用LCD19264显示温度等信息。实验结果表明,该实验系统具有操作简单、显示直观、精度高、可靠性高和维护方便等优点,具有良好的市场应用前景。更多还原

【Abstract】 A thermocouple experiment system is developed to meet the needs of the science and engineering students for the thermocouple experiments.This system uses MSP430F149 as the main controller to realize the temperature measurement at both high temperature and low temperature ends by platinum resistance.The instrument amplifier AD620 is used to amplify the weak signal of the thermocouple EMF,and the weak signal acquisition is realized by using ADC12 inside the main controller.The digital filter is used to filter the interference signal,and the linear interpolation method is adopted to solve the temperature value.Finally,the PWM signal is accepted to control the PTC and the fan.The temperature difference between the set temperature and the high temperature end is within 0.2 ℃.LCD19264 is adopted to display the information such as temperature,low temperature value,etc.The experimental results show that this experiment system has the advantages of simple operation,intuitive display,high accuracy,high reliability and convenient maintenance,and has a good market application prospect.更多还原