Exhaust recirculation apparatus for engine and method for controlling the same

摘要

An exhaust recirculation apparatus is provided to an engine. A high-pressure EGR passage branches from upstream of a turbine of a turbocharger in an exhaust system for recirculating exhaust gas to downstream of a compressor of the turbocharger in an intake system. A high-pressure EGR regulating unit controls exhaust gas through the high-pressure EGR passage. A low-pressure EGR passage branches from downstream of the turbine in the exhaust system for recirculating exhaust gas to upstream of the compressor in the intake system. A low-pressure EGR regulating unit controls exhaust gas through the low-pressure EGR passage. A control unit feedback-controls the high-pressure EGR regulating unit, and open-controls the low-pressure EGR regulating unit when exhaust gas is recirculated through the high-pressure EGR passage and the low-pressure EGR passage. The control unit feedback-controls the low-pressure EGR regulating unit when exhaust gas is recirculated through only the low-pressure EGR passage.