System and method for engine control

A system comprising:

• an exhaust gas recirculation (EGR) system coupled to an engine having a turbocharger, the EGR system including a first EGR valve and a second EGR valve;
• and
• a control unit configured to:
• determine a first amount of EGR that if provided to an intake of the engine would avoid turbocharger compressor surge in the turbocharger, determine a second amount of EGR that if provided to the intake would avoid turbocharger compressor choke in the turbocharger, and determine a third amount of EGR that if provided to the intake would avoid engine smoking;
• adjust the first and second EGR valves to deliver EGR to the intake in accordance with the determined first, second, and third amounts.

A system comprising:

• an exhaust gas recirculation (EGR) system coupled to an engine having a multi-stage turbocharger with a first stage and a second stage, the EGR system including a first EGR valve and a second EGR valve;
• and
• a control unit configured to:
• adjust the first and second EGR valves to deliver a first amount of EGR during steady state conditions;
• adjust the first and second EGR valves in response to a detected transient operating event to deliver a second amount of EGR based on designated mass air flow through the multi-stage turbocharger, wherein the designated mass air flow through the multi-stage turbocharger is further based on a position of a first bypass valve of the first stage and a position of a second bypass valve of the second stage;
• and
• provide advance opening of at least one of the first bypass valve or the second bypass valve in dependence upon a predetermined event.