Exhaust gas post-treatment system temperature controlling method for e.g. vehicle's oil engine, involves controlling period duration such that excess of energy in one mode is compensated by energy loss in other mode, to maintain temperature

摘要

The method involves dividing regeneration phase time into succession of divided periods (t1-t3), alternatively, in high and low hot combustion modes (P, R). Duration of each period is controlled such that excess of energy (S) in the period in the mode (R) is compensated by energy loss (D) in the other period in the mode (P) and vice-versa, to maintain an exhaust gas temperature (T2), at an outlet of a nitrogen-oxide trap type post-treatment unit i.e. oxidation catalyst, near an average temperature corresponding to a set temperature (Ts). A thermal input power (We) carried by the exhaust gas is higher/lower than a set power (Wc) necessary to obtain the temperature (Ts), in the respective high hot and low hot combustion modes.