Effect:
The function of automobile oxygen sensor is to determine whether there is excess oxygen in engine exhaust after combustion, i.e. oxygen content, and to convert oxygen content into electrical signal and transmit it to engine computer, so that the engine can achieve closed-loop control with excess air factor (lambda=1) as the goal, and ensure hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides in exhaust. (NO x) All three pollutants have the greatest conversion efficiency, and the transformation and purification of pollutants discharged and discharged are carried out to the greatest extent.
The principle of oxygen sensor is based on Nernst equation. By using the characteristics of solid electrolyte with high ionic conductivity and no electronic conductivity, when the working temperature (generally about 700 C) is reached, the oxygen partial pressure on both sides of the solid electrolyte is different and the concentration potential (Nernst potential difference) is generated between the two electrodes.
