Monitoring System of Harmful Substances Emission at Compression Ignition Engine with Exhaust Gas Recirculation

This paper describes conception of harmful substances emission monitoring system integrated with control system of EGR (Exhaust Gas Recirculation) at off-highway vehicles CI (Compression Ignition) engine. Proposed system based on standard sensors as temperature, rotational speed and also air flow meter sensor. Empirical modeling with consideration of signals of above mentioned sensors allow estimation of harmful substances concentration in exhaust gases. The goal to introduce this monitoring system is to indicate such control of emission reduction system as EGR to achieve advantageous engine emission properties. It is required to collaborate monitoring system with EGR control system equipped with actuator as prototype EGR valve controlled during CAN Bus (Controlled Area Network). Electronically controlled valve has very high precision and recurrence of opening steps what allow to realization of stable operated recirculation system. Besides of this possibility to flexible programming of valve operating mode allow to adapting of valve opening steps to CI engine operating condition changes. Replacement of expensive sensors specialized to measure chosen gas and matter concentration allow to minimizing cost of emission reduction systems applied at combustion engines. Publication included initial test bench research results of estimated exhaust gas and matter concentration. There are also proposed simple rules to application in advanced control algorithm of emission reduction system.