Egr system for compound turbocharged engine system

An engine system, comprising:

• a spark-ignited, gaseous-fuel-powered engine including at least ten engine cylinders, an intake manifold, and an exhaust manifold;
• a compound turbocharger system having a first turbine driving a first compressor, and a second turbine driving a second compressor;
• an intake line including the first compressor, the second compressor, and the at least one intake manifold;
• an exhaust line including the exhaust manifold, the second turbine, and the first turbine;
• an exhaust restriction valve located in the exhaust manifold of the engine downstream of a subset of the plurality of the engine cylinders, the subset including at least 25% of a total of the plurality of engine cylinders of the engine;
• and
• an exhaust gas recirculation line having an upstream end located to receive exhaust from the subset of the plurality of engine cylinders, and a downstream end coupled to the intake line downstream the first compressor and upstream of the second compressor.

A method of operating an engine system including an engine, a compound turbocharger system, an intake line, an exhaust line, and an exhaust gas recirculation line, the method comprising:

• supplying an intake fluid through the intake line including a first compressor and a second compressor of the compound turbocharger system, and to a plurality of engine cylinders;
• combusting the intake fluid in the plurality of engine cylinders;
• directing an exhaust from the cylinders through the exhaust line including a second turbine and a first turbine of the compound turbocharger system;
• and
• selectively routing exhaust from a subset of the plurality of the cylinders through the exhaust gas recirculation line to the intake line at a location downstream the first compressor and upstream the second compressor.