【摘要】 根据热导检测器的工作原理，分析影响其灵敏度的主要因素，并建立检测器的热平衡模型，可指导优化其性能设计。通过采用四壁直通式流通结构，选用10 kΩNTC热敏电阻作为热敏元件，设计稳定的恒流电源、高精度控温电路和信号处理电路，研制出高灵敏度的煤炭元素分析仪用热导检测器。经测试，检测器基线噪声为1.5μV,30 min内的基线漂移为8μV，灵敏度为12 288 mV·mL/mg，碳元素检出限为28.4μg/g，氢元素检出限为28.8μg/g，氮元素检出限为11.3μg/g，满足高通量煤炭元素分析仪多组分联测需求。更多还原

【Abstract】 According to the working principle of the thermal conductivity detector, the main factors affecting the sensitivity of the thermal conductivity detector are analyzed, and a thermal balance model to describe the performance of the thermal conductivity cell is established, which can guide the optimization of its performance design. By adopting a four-wall straight-through flow structure, selecting a 10 kΩ NTC thermistor as the thermal element, designing a stable constant current power supply, a high-precision temperature control circuit and a signal processing circuit, developing a highly sensitive thermal conductivity detector used in the coal element analyzer. After testing, the detector baseline noise is 1.5 μV, the baseline drift within 30 minutes is 8 μV, the sensitivity is 12 288 mV·mL/mg, and the detection limit of carbon is 28.4 μg/g, the detection limit of hydrogen is 28.8 μg/g, the detection limit of nitrogen is 11.3 μg/g, which meets the multi-component combined measurement requirements of high-throughput coal element analyzers.更多还原