Patent ID: 8234864

Claim:
An engine system including an engine, an intake system for providing intake air to the engine, and an exhaust system receiving exhaust gas from the engine, comprising: a first exhaust turbine arranged downstream of the engine; a second and third exhaust turbines coupled in parallel and arranged downstream of the first exhaust turbine; a first valve associated with the second and third exhaust turbines, the first valve configured to at least partially restrict exhaust gas to one of the second and third exhaust turbines and increase exhaust gas to the other turbine; a first compressor coupled to the third exhaust turbine; a second compressor coupled to the second exhaust turbine; a third compressor coupled to the first exhaust turbine; a second valve associated with one of the first and second compressors, the second valve configured to be selectively placed in one of an open position, a closed position, or a partially closed position that at least partially restricts a flow of air to one of the first and second compressors; and an exhaust gas recirculation system configured to redirect at least a portion of exhaust gas from the exhaust system to the intake system.