Control ammonia storage distribution

The NOx sensors were calibrated with a Horiba gas analyzer up to 1500 PPM and the ammonia sensors were calibrated with a FTIR up to 500 PPM. Notice that this experimental setup is to validate the concept of controlling ammonia storage distribution, and multiple NOx and NH3 sensors are used. The number of sensors used for SCR control can be limited in real applications due to cost consideration. 

Fig. 14.13 Schematic presentation of ammonia storage distribution control strategy [53]...

To verify this ammonia storage distribution control approach in practice, a two-catalyst SCR system is developed. A controller is designed to control the AdBlue injection such that the ammonia coverage ratio of the upstream catalyst is kept at a higher value and the ammonia coverage ratio of the downstream catalyst is limited under a lower level as presented in Fig. 14.13. 

Hsieh M-F, Wang J (2012) Adaptive and efficient ammonia storage distribution control fora two-catalyst SCR system, ASME Journal of Dynamic Systems, Measurement and Control, 134(1) 011012. 

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