A dual EGR loop exhaust gas recirculation (EGR) system for an internal combustion engine. The engine has both a dedicated EGR loop and a low pressure EGR loop. This means that one or more engine cylinders is operable as a dedicated EGR cylinder, such that all of its exhaust is recirculated via the dedicated EGR loop. The other cylinders are operable as main cylinders having two intake ports, such that each main cylinder may receive a mixture of fresh air and dedicated EGR through one intake port and a mixture of fresh air and low pressure EGR through the other intake port. A control unit controls this dual loop EGR system to either provide EGR only from the dedicated EGR loop or to also provide additional EGR from the low pressure EGR loop.
Raphael Gukelberger; Jess W. Gingrich