变频式氧传感器输出特性的研究

Research on output characteristics of variable frequency oxygen sensor

介绍了一种新式氧化锆固体电解质变频式氧传感器，其结构由敏感电池和氧泵两部分复合构成。理论推导在浓差电势E1—E2范围的响应时间t与被测氧分压P1呈正比关系。实验测试数据显示：在保持浓差电势E1，E2在均不超过200mV的范围时，时间t与被测氧分压P1之间的确呈现出非常好的正比关系，线性相关系数R均大于0．986。但当电势E1，E2超过200mV后，实验结果却与理论严重不符。经过初步分析，当浓差电势超过一定值后，空腔内的较低氧分压改变了固体电解质性质，使氧泵的电导率发生了变化导致理论推导的偏差。

A new type of variable frequency oxygen sensor of zirconia solid electrolyte ,whose structure is made of sensitive cell and oxygen pump, is introduced. In theory, the response time （ t ） is proportional to the measured oxygen pressure Pl varies from E1 to E2 of concentration voltage. The detailed experiment data show that the relation of the response time t with the measured oxygen pressure pl is direct proportional when keeping the concentration voltage E1 and E2 under 200 mV. However, the result of experiment disaccords with theoretic formula when the concentration voltage E1 and E2 exceed 200 mV. Through preliminary analysis, it predicts that the conductance of zirconia solid electrolyte is changed by low oxygen pressure inside chamber when the concentration voltage E1 and E2 exceed 200 mV, which brings the deviation of theoretic derivation.