SYSTEM AND METHOD FOR ADAPTIVE CONTROL OF AMMONIA-NOX RATIO

An ammonia to NOx ratio (ANR) control system includes an internal combustion engine configured to combust fuel, a valve configured to provide the fuel to the internal combustion engine, and a selective catalytic reduction (SCR) catalyst connected to the internal combustion engine to receive exhaust generated by combustion of the fuel with the internal combustion engine. The system also includes a reductant injector configured to inject reductant for the SCR catalyst, a sensor connected downstream of the SCR catalyst, and a controller. The controller may be configured to: receive NOx level signals or NHlevel signals from the sensor, generate commands for controlling the reductant injector, and determine, with a perturbation-based control algorithm and based on the NOx or NHlevel signals, commands for controlling the reductant injector.