Engine system and control method using the same

An engine system comprising:

• an intake line through which fresh air, which is to be supplied into a combustion chamber of an engine, flows;
• an exhaust line through which exhaust gas discharged from the combustion chamber flows;
• an exhaust gas recirculation (EGR) system which recirculates some of the exhaust gas which is discharged from the combustion chamber back to the combustion chamber;
• a turbocharger including:
• a turbine disposed in the exhaust line and rotating by the exhaust gas discharged from the combustion chamber;
• and a compressor, which is disposed in the intake line, rotating in conjunction with the rotation of the turbine and compressing outside air;
• an intercooler disposed in the intake line at a rear end of the compressor;
• an intake bypass line penetrating the intercooler from the intake line at a front end of a throttle valve, which adjusts the amount of intake gas to be supplied into the combustion chamber, the intake bypass line merging into the intake line at a front end of the compressor;
• a recirculation valve disposed in the intake bypass line;
• and
• a controller controlling opening and closing of the recirculation valve so that some of the intake gas compressed by the compressor is supplied into the intake line at the front end of the compressor through the intake bypass line or the intake gas is supplied into the combustion chamber through the intake bypass line,
• wherein the recirculation valve includes:
• a housing having a flow path formed therein;
• a first passageway communicating with the flow path and communicating with the intake line at the front end of the compressor;
• a second passageway communicating with the flow path and communicating with the intake line at the front end of the throttle valve;
• a third passageway communicating with the flow path and communicating with the intake line connected with the intercooler;
• and
• a actuator selectively closing the first passageway.