Estimating nitrogen oxide values for vehicles

A system comprising:

• a nitrogen oxide sensor coupled to an engine, a selective catalytic reduction (SCR) unit, or both, of a propulsion system for a vehicle, the nitrogen oxide sensor configured to generate in initial nitrogen oxide measurement;
• a memory configured to store a kinetic model of the SCR unit and a reaction model of the nitrogen oxide sensor;
• and
• a processor configured to at least facilitate:
• obtaining a nitrogen oxides concentration value pertaining to a selective catalytic reduction (SCR) unit of the propulsion system;
• obtaining the initial nitrogen oxide concentration measurement via the nitrogen oxide sensor of the propulsion system;
• using the nitrogen oxides concentration value as a first input for the kinetic model of the SCR unit stored in the memory, generating an SCR kinetic model output from the kinetic model of the SCR unit;
• using the nitrogen oxides concentration value as a second input for the reaction model of the nitrogen oxide sensor, generating a nitrogen oxide sensor reaction model output from the kinetic model of the nitrogen oxide sensor;
• and
• estimating an updated value for the initial nitrogen oxide measurement based on both the SCR kinetic model output and the nitrogen oxide sensor reaction model output.

A vehicle comprising:

• an engine;
• a selective catalytic reduction system (SCR) unit coupled to the engine;
• a nitrogen oxide sensor coupled to the engine, the SCR unit, or both, the nitrogen oxide sensor configured to generate in initial nitrogen oxide measurement;
• a memory configured to store a kinetic model of the SCR unit and a reaction model of the nitrogen oxide sensor;
• and
• a processor configured to at least facilitate:
• obtaining a nitrogen oxides concentration value pertaining to the (SCR) unit;
• using the nitrogen oxides concentration value as a first input for the kinetic model of the SCR unit, stored in the memory, generating an SCR kinetic model output from the kinetic model of the SCR unit;
• using the nitrogen oxides concentration value as a second input for the reaction model of the nitrogen oxide sensor, generating a nitrogen oxide sensor reaction model output from the kinetic model of the nitrogen oxide sensor;
• and
• estimating an updated value for the initial nitrogen oxide measurement based on both the SCR kinetic model output and the nitrogen oxide sensor reaction model output.