METHOD TO CONTROL THE AMOUNT OF PARTICULATE COMING OUT OF A PARTICULATE FILTER FOR AN INTERNAL COMBUSTION ENGINE

1 . A method to control the amount of particulate ({dot over (m)} OUT ) coming out of a particulate filter ( 10 ) for an internal combustion engine ( 1 ) comprising the steps of:

estimating an objective value of the amount of particulate ({dot over (m)} OUT ) coming out of the particulate filter ( 10 ), which is capable of meeting the legal requirements;

estimating a trapping efficiency (η GPF ) of the particulate filter ( 10 ) based on an estimation model using measured and/or given physical quantities so as to obtain the objective value ({dot over (m)} OUT ) of the amount of particulate coming out of the particulate filter ( 10 );

determining an amount of particulate ({dot over (m)} GPF ) trapped in the particular filter ( 10 ), which allows reaching said trapping efficiency (η GPF );

adjusting an amount of particulate ({dot over (m)} IN ) produced by the internal combustion engine ( 1 ) and flowing into the particulate filter ( 10 ) and/or an amount of particulate ({dot over (m)} B ) burnt in the particulate filter ( 10 ) so as to obtain said amount ({dot over (m)} GPF ) of trapped particulate.

2 . A method according to claim 1 , wherein the step of adjusting the amount of particulate ({dot over (m)} B ) burnt in the particulate filter ( 10 ) comprises adjusting the engine cut-off phase, during which the delivery of fuel, which takes place during the release phase, is interrupted.

3 . A method according to claim 2 , wherein the step of adjusting the engine cut-off phase comprises inhibiting or permitting the engine cut-off phase for a time lapse having a predetermined duration (ΔT).

4 . A method according to claim 1 , wherein the step of adjusting the amount of particulate ({dot over (m)} IN ) produced by the internal combustion engine ( 1 ) and flowing into the particulate filter ( 10 ) comprises controlling the parameters that adjust the production of particulate in the internal combustion engine ( 1 ).

5 . A method according to claim 4 , wherein the step of adjusting the amount of particulate ( m IN ) produced by the internal combustion engine ( 1 ) and flowing into the particulate filter ( 10 ) comprises controlling any operating parameter or any combination of the operating parameters chosen among the following ones:

number of injections (single main injection or multi-injection);

sequence (or pattern) of reference injections to be operated for each cylinder;

start of injection angle SOI associated with each injection;

end of injection angle EOI associated with each injection;

amount of fuel injected with each injection;

pressure of fuel injected with each injection;

air/fuel equivalence ratio of the exhaust gas.