本文针对高精度温度传感器测温效率低,提出了一种高精度批量测温系统及其测试方法,且具有多芯测试能力。 针对 铂电阻 PT100 测试精度低,提出了分类法、二分扫描法、逐次逼近法对铂电阻 PT100 进行校准,校准后在-65 ℃ ~ 145 ℃ 温度区 间最大测温误差值由 0. 412 ℃ 变为 0. 021 ℃ ,测温精度提升 94. 9%。 同时建模仿真了系统的稳定性、测温时间和测温精度,首 先对恒温装置外壁到内壁和内部腔体冷流体的对流换热进行传热学建模,仿真结果表明恒温装置只需 75. 2 s 便能够达到热平 衡;接着对待测电路发热、基座散热、校准后铂电阻进行综合热仿真建模,仿真结果表明系统测温精度可达 0. 016 ℃ ;最后对几 款经典高精度温度传感器的外温和内温进行测试验证,结果表明系统能够对 0. 031 ℃测温精度的温度传感器进行测试,系统能 够很好满足测温需求。
This article proposes a high-precision batch temperature measurement system and testing method for low temperature measurement efficiency of high-precision temperature sensors, the system with the ability testing multiple cores. This article proposes classification method, binary scanning method, and successive approximation method to calibrate the platinum resistance PT100 for the low testing accuracy of platinum resistance PT100. After calibration, the maximum temperature measurement error value in the temperature range of -65 ℃ to 145 ℃ is changed from 0. 412 ℃ to 0. 021 ℃ , and the temperature measurement accuracy is improved by 94. 9%. Simultaneously, the stability, temperature measurement time, and temperature measurement accuracy of the system are modeled and simulated. Firstly, Heat transfer modeling is conducted for the outer wall to the inner wall and convective heat transfer of cold fluid in internal cavity of the thermostatic device respectively. The simulation result shows that the thermostatic device can achieve heat balance in only 75. 2 seconds. Then, the tested circuit heating up, the base heating up, and the calibrated platinum resistance is modeled by comprehensive thermal simulation. The simulation result shows that the temperature measurement accuracy of the system can reach to 0. 016 ℃ . Finally, the external and internal temperatures of several classic high-precision temperature sensors are tested and verified, and the result shows that the system can test temperature sensors with a temperature measurement accuracy of 0. 031 ℃ , which can well meet the temperature measurement requirements.
陈相洪,史凡萍,杨 鹏,彭 伟,杨晓强,闫军山.基于高精度数字温度传感器测试系统及建模仿真[J].电子测量与仪器学报,2023,37(7):42-52复制