Oxygen sensor adaptive impedance control
AssigneeFord Global Technologies, LLC
InventorsWilliam Goodwin, Scott Eckstein Brodesser, Kenneth John Behr, John Joseph Virga
Life of this patent
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Abstract
Methods and systems are provided for adapting a target impedance of an oxygen sensor. In one example, a method may include updating a target impedance of an oxygen sensor based on a difference between an estimated voltage across a sensing element of the oxygen sensor and a reference RMS voltage of the sensing element. The temperature of the oxygen sensor may be adjusted based on the updated target impedance.
Claims20
A method for an engine of a vehicle, comprising:
- updating an initial target impedance of an oxygen sensor based on a difference between a commanded root mean square (RMS) voltage across a sensing element of the oxygen sensor and a reference RMS voltage of the sensing element corresponding to the initial target impedance, and adjusting a temperature of the oxygen sensor based on the updated target impedance.
A method for an oxygen sensor in an engine, comprising:
- upon conditions for target impedance adaptation being met,
- estimating a commanded RMS voltage across a sensing element of the oxygen sensor corresponding to a set of current vehicle operating conditions and a current, first target impedance;
- retrieving a reference RMS voltage of the sensing element corresponding to the set of current vehicle operating conditions and the first target impedance;
- estimating a second target impedance as a function of a difference between the commanded RMS voltage and the reference RMS voltage;
- and
- adjusting a temperature of the oxygen sensor based on the second target impedance.
A system for an engine in a vehicle, comprising:
- an oxygen sensor;
- and
- a controller storing instructions in non-transitory memory that, when executed, cause the controller to:
- at an initiation of a drive cycle, adjust power supplied to a heating element in thermal contact with a sensing element of the oxygen sensor based on an initial target impedance;
- and
- upon a temperature of the oxygen sensor increasing to an operating temperature range during a steady engine speed and engine load condition,
- estimate a difference between a weighted, commanded RMS voltage across the sensing element of the oxygen sensor and a weighted, reference RMS voltage corresponding to the initial target impedance and current vehicle operating conditions;
- update the initial target impedance based on the difference;
- and
- adjust power supplied to the heating element based on the updated target impedance.
Dependencies are inferred from the claim text.