| 摘要 |
<P>PROBLEM TO BE SOLVED: To properly control a suction air amount during the transient operation of an internal combustion engine in an EGR system in which both a high-pressure EGR and a low-pressure EGR are used. <P>SOLUTION: This exhaust gas recirculation system comprises a turbocharger having a compressor in a suction passage and a turbine in an exhaust passage, a high-pressure EGR means for performing EGR through a high-pressure EGR passage connecting the exhaust passage on the upstream side of the turbine to the suction passage on the downstream side of the compressor, a low-pressure EGR means for performing EGR through a low-pressure EGR passage connecting the exhaust passage on the downstream side of the turbine to the suction passage on the upstream side of the compressor, a high-pressure EGR valve installed in the high-pressure EGR passage, and a low-pressure EGR valve installed in the low-pressure EGR passage. During the transient operation of the internal combustion engine, first the opening of the high-pressure EGR valve is controlled by feedback. After the opening of the high-pressure EGR valve is fully closed, the opening of the low-pressure EGR valve is controlled by feedback. The suction air amount is quickly controlled to a target suction air amount without causing hunching. <P>COPYRIGHT: (C)2008,JPO&INPIT |
