小型燃煤锅炉温度采集系统的设计与实现

Design and Implementation of Temperature Acquisition System for Small Coal-fired Boiler

针对小型燃煤锅炉系统不同工质温度采集范围广的特点,设计基于单片机的小型燃煤锅炉温度采集系统。系统主要由K型热电偶、MAX6675温度转换芯片、Atmega128单片机及TCM12864 LCD组成。温度数据经K型热电偶采集、MAX6675放大、冷端补偿、线性化及SPI串口数字化后,送入单片机Atmega128处理并实时显示于TCM12864 LCD上。系统采集温度范围为0～700℃,最大非线性误差小于3.00%。MAX6675与Atmega128串行SPI接口的使用简化了系统的软硬件设计。实际测试结果表明该系统具有良好的性能,能够满足应用要求。

In view of the characteristics of small coal-fired boiler system that may run under the coexistence of different working fluids, a MCU based temperature acquisition system is designed. The system mainly consists of K-type thermocouple, MAX6675, Atmega128 and TCM12864LCD. Temperature data are collected by the K-type thermocouple, amplified, cold junction compensated, linearized, and digitized with SPI interface by MAX6675, processed with Atmega128 MCU and displayed on TCM12864 LCD. The temperature acquisition range is from 0 to 700 ℃, and the maximttm linear error is below 3%. The utilization of SPI interface between MAX6675 and Atmega128 simplifies the design of both hardware and software. Test results show that the temperature acquisition system has good performance and can satisfy the requirements of this application.