Control device (20) for an
internal combustion engine (100) which controls an
internal combustion engine (100) which includes an
intercooler (7) which cools the intake air and an EGR flow path
pipe (40) which returns a portion of the
exhaust gas in an exhaust path to an upstream side of the
intercooler (7) as EGR gas, wherein the control device (20) for the
internal combustion engine (100) comprises: a
moisture quantity calculation unit (301, 301B, 302, 302B, 302C, 302D) configured to calculate a total
moisture quantity contained in a
mixed gas obtained by mixing
fresh air flowing into the charge air cooler (7) and the EGR gas; a
dew condensation calculation unit (303) configured to calculate a
dew condensation generation quantity (WQcon) in the charge air cooler (7) based on the total
moisture quantity calculated by the moisture quantity calculation unit (301, 301B, 302, 302B, 302C, 302D); a
dew condensation determination unit (303) configured to set an end dew condensation generation quantity (WQcon2) to 0 if the calculated dew condensation generation quantity (WQcon) does not exceed a predetermined threshold (SL), and to set the end dew condensation generation quantity (WQcon2) to the calculated dew condensation generation quantity (WQcon) if the calculated dew condensation generation quantity (WQcon) exceeds the predetermined threshold (SL); an EGR correction unit (304) configured to correct a flow rate of the returned EGR gas based on the final dew condensation generation quantity (WQcon2) set by the dew condensation determination unit (303); a first moisture quantity calculation unit (301, 301B) configured to calculate a first moisture quantity (WQair) which is a moisture quantity contained in the
fresh air; and a second moisture quantity calculation unit (302, 302B, 302C, 302D) configured to calculate a second moisture quantity (WQegr) which is a moisture quantity contained in the EGR gas, wherein the total moisture quantity is a sum of the first moisture quantity (WQair) and the second moisture quantity (WQegr), wherein the second moisture quantity calculation unit (301, 301B, 302, 302B, 302C, 302D) is designed to calculate the second moisture quantity (WQegr) based on a fuel property, a target EGR rate (TEGR) of the EGR gas before correction by the EGR correction unit (304) and an intake air quantity (Qair), and wherein the EGR correction unit (304) contains an EGR gas correction table in which EGR gas correction amounts (HOSegr) for correcting the EGR gas according to the final dew condensation generation amount (WQcon2) are set such that as the final dew condensation generation amount (WQcon2) increases the EGR gas correction amount (HOSegr).