Adaptive oxygen sensor methods, systems, and software

Abstract

One embodiment is a system operable to control entry of an oxygen sensor into a learning mode. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.

1 . A system comprising:
 an exhaust aftertreatment subsystem;   an oxygen sensor coupled to the exhaust aftertreatment subsystem; and   a controller operable to command the oxygen sensor to enter a learning mode when an EGR condition is satisfied.   
   
   
       2 . A system according to  claim 1  wherein entry into the learning mode further requires an exhaust pressure condition is satisfied. 
   
   
       3 . A system according to  claim 1  wherein entry into the learning mode further requires a regeneration condition is satisfied, an exhaust pressure condition is satisfied, an EGR override condition is satisfied, and an oxygen sensor fault condition is satisfied. 
   
   
       4 . A system according to  claim 1  wherein the EGR condition includes an information of a position of an EGR valve. 
   
   
       5 . A system according to  claim 1  wherein entry into the learning mode further requires that at least 20 seconds have passed since a regeneration event of the aftertreatment subsystem. 
   
   
       6 . A system according to  claim 1  wherein entry into the learning mode further requires determination or evaluation of whether at least one of the following errors is associated with the oxygen sensor: a high threshold rationality error, a low threshold rationality error, temperature error, a heater error, a supply voltage error, and a communications interface timeout error. 
   
   
       7 . A system according to  claim 1  wherein the learning mode includes executing instructions to reduce error of a measurement by the oxygen sensor. 
   
   
       8 . A system according to  claim 1  wherein the learning mode includes adjusting the oxygen sensor according to one or more engine operating conditions. 
   
   
       9 . A system according to  claim 1  wherein entry into the learning mode further requires determination or evaluation of whether at least one of the following errors is associated with an oxygen sensor: a high threshold rationality error, a low threshold rationality error, temperature error, a heater error, a supply voltage error, and a communications interface timeout error. 
   
   
       10 . A system according to  claim 1  wherein entry into the learning mode further requires determination or evaluation of whether an ERG valve is closed. 
   
   
       11 . A system according to  claim 1  wherein entry into the learning mode further requires determination or evaluation of a pressure differential across a diesel particulate filter. 
   
   
       12 . A method comprising:
 evaluating a regeneration event condition;   evaluating an EGR mode condition; and   controlling initiation of an oxygen sensor learning mode based upon the evaluating a regeneration event condition and the evaluating an EGR mode condition.   
   
   
       13 . A method according to  claim 12  wherein the regeneration event condition includes evaluation of whether time since a regeneration event has exceeded a time threshold. 
   
   
       14 . A method according to  claim 12  wherein the EGR mode condition includes evaluation of an information of EGR valve position. 
   
   
       15 . A method according to  claim 14  wherein the EGR mode condition includes evaluation of a source of the information of EGR valve position. 
   
   
       16 . A method according to  claim 12  further comprising evaluating a pressure condition; wherein the controlling initiation of an oxygen sensor learning mode is further based upon the evaluating a pressure condition. 
   
   
       17 . A method according to  claim 16  wherein the evaluating a pressure condition includes evaluating a pressure differential across a diesel particulate filter. 
   
   
       18 . A method according to  claim 16  wherein the evaluating a pressure condition includes evaluating ambient pressure. 
   
   
       19 . A computer readable medium configured to store information comprising:
 instructions executable to evaluate a regeneration conditional;   instructions executable to evaluate an exhaust gas recirculation conditional; and   instructions executable to control initiation of an oxygen sensor learning mode based upon at least one of the evaluation of the regeneration conditional and the evaluation of the exhaust gas recirculation conditional.   
   
   
       20 . A computer readable medium according to  claim 19  operatively coupled with an engine control module. 
   
   
       21 . A computer readable medium according to  claim 19  operatively coupled with an engine control module and an internal combustion engine. 
   
   
       22 . A computer readable medium according to  claim 19  operatively coupled with an engine control module a diesel engine and a vehicle.