中圖分類號(hào)： TP274
文獻(xiàn)標(biāo)識(shí)碼： A
DOI：10.16157/j.issn.0258-7998.211896
中文引用格式： 王樂群，文豐，張凱華. 基于FPGA的高精度S型熱電偶溫度測量系統(tǒng)設(shè)計(jì)[J].電子技術(shù)應(yīng)用，2022，48(2)：41-45.
英文引用格式： Wang Lequn，Wen Feng，Zhang Kaihua. Design of temperature measuring circuit of S-type thermocouple based on temperature sensor[J]. Application of Electronic Technique，2022，48(2)：41-45.

Design of temperature measuring circuit of S-type thermocouple based on temperature sensor

Abstract： Aiming at the problem that the traditional multi-channel S-type thermocouple temperature measurement system has low measurement accuracy and each channel is quite different, a high-precision S-type thermocouple temperature measurement system based on FPGA is proposed.The system uses FPGA as controller, with modular design, and uses AD590 to perform cold junction compensation for S-type thermocouples.A high-precision ADC is used to convert the collected temperature analog signal into a digital signal and transmit it to the upper computer for display and locates the temperature value through the look-up table method to improve the temperature measurement accuracy.After many tests, it is verified that the temperature acquisition accuracy of this temperature measurement circuit is better than 0.2%F.S. At present, the circuit design has been applied to engineering practice, which provides an effective and reliable means for the design of temperature measuring circuit of S-type thermocouple.

Key words : S-type thermocouple；FPGA；cold end compensation；RFI filter circuit；high precision