基于单片机的K型热电偶冷端自动补偿设计

Design of Cold End Self-motion Compensation of K Thermal Couple on the Basis of Single Chip

以单片机强大的数据处理功能为基础,以试验数据的拟合而不是理想集成运放的计算公式为测量依据,提出了检测环境电势和现场电势的新方法,并根据两者之和即为热电偶标准电势这一基本依据,设计了热电偶冷端自动补偿系统的硬件及相关软件。由于采用了软件对各电势信号处理,大大简化了传统补偿电路,使硬件设计仅包括环境温度测量、现场电势测量及单片机的信号处理三个模块,并且显著降低了成本。仿真及试验结果表明,本补偿系统可使控温最大偏差<5℃。

On the basis of strong function of processing data by single chip a new method of testing environmental voltage and local voltage was presented in this paper, the measuring foundation of which is simulation of experimental but not ideal formula. The design of the com- pensation system was based on the fact： the sum of two voltage is the standard voltage. Because software was used to process voltage sign, the circuit was simplified evidently. The whole design include only three part, i.e. environmental temperature testing, local voltage testing and sign processing of single chip. Meanwhile, the cost decreased remarkably. The results of emulation and experiment show that, the compensation system can make the maximum error less than 5℃.