US Patent 11852061 Vehicle exhaust gas reduction system and method thereof

A vehicle exhaust gas reduction system positioned in an exhaust system of an engine includes: an electrically heated catalyst (EHC) of heating exhaust gas of the engine by electrically generating heat; a sub-gasoline particulate filter (Sub GPF) heated by operation of the EHC to combust a particulate number (PN) included in the exhaust gas; a main gasoline particulate filter (Main GPF) of purifying the exhaust gas discharged from the engine; and a controller configured for performing PN reduction control by operating the EHC to be On in a low-temperature condition, and increasing a temperature of the Sub GPF to a reference temperature at which soot combustion is possible, combusting the PN passing through the Sub GPF and soot collected in the Sub GPF.