Exhaust gas recirculating system for an engine with a turbocharger, comprises a first exhaust gas recirculating unit, a second exhaust gas recirculating unit, a determining unit, and a switching unit

摘要

Exhaust gas recirculating system comprises a first exhaust gas recirculating unit for passing waste gas from a region upstream of a turbine (16) of a turbocharger (12) into a region downstream of a compressor (20) of the turbocharger, a second exhaust gas recirculating unit for passing exhaust gas from a region downstream of the turbine into a region upstream of the compressor, a first determining unit (36) for determining whether the first recirculating unit can prepare a required exhaust gas recirculating amount or not, and a switching unit for switching from the exhaust gas recirculation based on the first recirculating unit into the exhaust gas recirculation based on the second recirculating unit when the first recirculating unit determines that the first unit is not able to prepare the required exhaust gas recirculation amount. An Independent claim is also included for an exhaust gas recirculating process using the above system.