通过分析温度对金属氧化物气体传感器性能影响的过程,提出一种自适应温度调制模式的传感器气敏性能研究方法,着重阐述自适应温度调制模式的工作原理,设计以气敏单元电阻值为反馈信号的传感器闭环控制加热电路,借助于电路模拟方法,获取在不同气体下传感器温度响应曲线.结果表明:在相同的计数长度k和不同气体组分下,温度响应曲线各不相同.以H2为例,传感器的温度范围为140～220℃,传感器温度变化周期为800ms,其中上升时间长度为300ms,下降时间长度为500ms,为定性分析气体种类和定量分析气体浓度提供了大量的传感器响应信息.%A self-adapted temperature modulation was proposed to study gas sensing properties by analyzing the process of the temperature role on the performance of metal oxide gas sensors. The working principle of the self-adapted temperature modulation was presented, a closed-loop circuit connecting the sensor resistance to the sensor heater was designed and temperature response curves of sensors in different kinds of gas were obtained by circuit simulaiton. Different kinds of gas had unique temperature response curve formed by the same number of pulses but with different lengths. Using hydrogen as an example, the sensor temperature range was 140-220 ℃ , the temperature pulse cycle was 800 ms, the upper semi-period was 300 ms and the down semi-period was 500 ms. It provided many information about sensor response for the qualitative analysis of gas species and gas concentrations.
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