Experimental validation of a virtual engine-out NOx sensor for diesel emission control

Motivated by automotive emission legislations, a Virtual [Formula: see text] sensor is developed. This virtual sensor consists of a real-time, phenomenological model that computes engine-out [Formula: see text] by using the measured in-cylinder pressure signal from a single cylinder as its main input. The implementation is made on a Field Programmable Gate Array–Central Processing Unit architecture to ensure the [Formula: see text] computation is ready at the end of the combustion cycle. The Virtual [Formula: see text] sensor is tested and validated on an EURO-VI Heavy-Duty Diesel engine platform. The Virtual [Formula: see text] sensor is proven to meet the accuracy of a production [Formula: see text] sensor for steady-state conditions and has better frequency response compared to the production [Formula: see text] sensor.