汽油杂质对氧传感器响应特性的影响

Impacts of Impurities in Gasoline on Response Characteristic of Oxygen Sensor

汽油中的硫、磷、铅、锰、硅等微量杂质会严重影响电喷发动机系统中氧传感器的氧敏效应, 是使氧传感器失效的主要原因之一。分析了这些杂质对氧传感器响应特性的影响以及损坏氧传感器的主要原因。研究发现:硫和锰会与氧传感器中的多孔铂电极发生反应,降低电极活性而恶化由稀至浓响应速度。铅会与铂电极形成低共熔物,延长氧传感器的响应时间。而硅和磷的作用主要在于对多孔电极层和保护层的严重堵塞。

Trace impurities such as S,P,Pb,Mn,Si in gasoline have bad influences on oxygen sensibility of oxygen sensor in EMS system, and become one of main reasons to damage oxygen sensor. The impacts of impurities on response characteristic and reasons of invalidation of oxygen sensor were discussed. Sulfur and manganese will react with porous platinum electrode of oxygen sensor and deteriorate sensibility from lean oxygen content to rich one. Plumbum will prolong sensitive time of the sensor through co-melting with platinum eletcr Fode,while jam action of porous electron and protective cover with silicon or phosphor are main reason to damage oxygen sensor.