Heated Zirconia Oxygen Sensor for Stoichiometric and Lean Air-Fuel Ratios

This publication describes the design and operation of an electrically heated ZrO₂ sensor and demonstrates its advantages in comparison to the present unheated sensor in a λ = 1 system.

Control ability down to very low exhaust temperatures, minimized temperature dependence and reduced aging effects result in lower emissions with the heated sensor. The application advantages in a λ = 1 system are discussed.

The second part of the paper discribes the properties of this heated sensor for measurement of lean exhaust gas. The λ-range 1.0 to 1.5 can be covered without any additional temperature compensation with sufficient accuracy and stability over life time.