銅-康銅熱電偶的標(biāo)定與誤差分析

陳良[1,2] 侯予[1] 習(xí)蘭[1,2]
[1]西安交通大學(xué)動(dòng)力工程多相流國家重點(diǎn)實(shí)驗(yàn)室,西安710049 [2]西安交通大學(xué)能源與動(dòng)力工程學(xué)院,西安710049
摘　要:開發(fā)了基于Labview的溫度測量系統(tǒng)，對(duì)銅．康銅熱電偶在-70℃至10℃范圍內(nèi)進(jìn)行了標(biāo)定，并且進(jìn)行了誤差分析。比較了不同焊接工藝和不同參考端補(bǔ)償方式對(duì)熱電偶性能的影響，分別對(duì)標(biāo)定結(jié)果進(jìn)行了線性、二次、三次和四次最小二乘擬合，并且分析了擬合誤差。最后對(duì)使用冰點(diǎn)槽、Keithley自動(dòng)補(bǔ)償模塊和Aglient自動(dòng)補(bǔ)償模塊的熱電偶標(biāo)定裝置進(jìn)行了分析。分析結(jié)果表明：若焊接質(zhì)量得到保證，錫焊和對(duì)焊工藝對(duì)熱電偶性能影響不大，可滿足對(duì)測量精度的要求；與采用冰點(diǎn)槽作為補(bǔ)償端相比，線路板內(nèi)置的溫度補(bǔ)償系統(tǒng)使用方便，但精度較差，不宜在熱電偶的標(biāo)定中使用。[著者文摘]

Calibration of copper-constantan thermocouple and related error analysisChen Liang, Hou Yu, Xi Lan1 State Key Laboratory of Multiphase Flow in Power Engineering,Xihn Jiaotong University,Xi＇an 710049, China;2 School of Energy and Power Engineering, Xihn Jiaotong University, Xi＇an 710049, ChinaAbstract:Copper-constantan thermocouples were calibrated from - 70 ℃ to 10 ℃ and error analysis was presented. A temperature measurement system based on Labview was developed. Effects of welding methods and reference junctions on the accuracy of thermocouples were analyzed. Then the least square fittings with one order, second order, third order and fourth order were respectively performed on the test da- ta. Error analysis on the calibration apparatus was conducted. The results show that thermoeouples fabricated through soldering had comparative accuracy as thermocouples fabricated through butt welding. Model 7 014 Multiplexer Card （Keithley Instruments, Inc. ） and Aglient 34 921A Multiplexer Module （Aglient Technologies, Inc. ） were unsuitable for the temperature measurement at the reference junction in the calibration of thermocouples.[著者文摘]

Key words:thermocouples ; calibration ; error analysis