Abstract: A dual turbocharger system for an engine is provided. In one example, the dual turbocharger system may include two variable geometry turbines (VGTs), with each turbine being of the same size and operating in parallel, and with each compressor of the turbocharger operating in series, the first compressor of the first turbocharger being larger than the second compressor of the second turbocharger.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, each of a first valve positioned in an exhaust gas recirculation (EGR) passage, the EGR passage coupled between the intake passage and the first exhaust manifold coupled to a first set of cylinder exhaust valves, and a second valve positioned in a flow passage coupled between the first exhaust manifold and the exhaust passage may be adjusted based on a measured pressure in the first exhaust manifold.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation (EGR) to an intake passage via a ported scavenge manifold. In one example, the ported scavenge manifold includes a first scavenge manifold coupled to a plurality of exhaust runners and a second scavenge manifold coupled to the plurality of exhaust runners via ports. The location of the ports on the exhaust runners combined with adjustments to a bypass valve coupled between the first scavenge manifold and an exhaust passage and an EGR valve coupled between the second scavenge manifold and the intake passage enables exhaust gas to be preferentially flowed to the exhaust passage and blowthrough air to be preferentially flowed to the intake passage under select operating conditions.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, an intake valve timing, exhaust valve timing of a first set of exhaust valves coupled to the first exhaust manifold, and a position of an exhaust gas recirculation (EGR) valve in an EGR passage may be adjusted in coordination with one another in response to a condition at a compressor. The EGR passage may be coupled between the intake passage, upstream of the compressor, and the first exhaust manifold.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, each of a first valve positioned in an exhaust gas recirculation (EGR) passage, the EGR passage coupled between the intake passage and the first exhaust manifold coupled to a first set of cylinder exhaust valves, and a second valve positioned in a flow passage coupled between the first exhaust manifold and the exhaust passage may be adjusted based on a measured pressure in the first exhaust manifold.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, each of a first valve positioned in an exhaust gas recirculation (EGR) passage, the EGR passage coupled between the intake passage and the first exhaust manifold coupled to a first set of cylinder exhaust valves, and a second valve positioned in a flow passage coupled between the first exhaust manifold and the exhaust passage may be adjusted based on a measured pressure in the first exhaust manifold.

Abstract: Methods and systems are provided for controlling boost pressure and exhaust gas recirculation in a split exhaust system. In one example, a first portion of exhaust may be routed from a cylinder to an exhaust turbine via a first exhaust valve and a second, remaining portion of exhaust may be routed as exhaust gas recirculation (EGR) via a second exhaust valve, the timing and lift of each of the first valve profile and the second valve profile adjusted based on boost error and EGR error. Further, motor torque from an electric motor may be supplied to the turbocharger to attain a desired boost pressure and a desired EGR flow.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, a first set of exhaust valves coupled to the first exhaust manifold may be operated at a different timing than a second set of exhaust valves coupled to the second exhaust manifold. Further, a position of a first valve positioned in a first passage coupled between the intake passage and the first exhaust manifold and/or a timing of the first set of exhaust valves may be diagnosed based on an output of a pressure sensor positioned in the first exhaust manifold.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, a flow of exhaust (e.g., exhaust gas recirculation) from engine cylinders to the intake passage, upstream of a compressor, via an exhaust gas recirculation (EGR) passage and the first exhaust manifold may be adjusted by adjusting a timing of a first set of cylinder exhaust valves coupled to the first exhaust manifold. Additionally, the first set of cylinder exhaust valves open at a different time than a second set of cylinder exhaust valves coupled to the exhaust passage.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, in response to an electric motor driving an electric compressor positioned upstream of a turbocharger compressor disposed in the intake passage, a position of a valve in an exhaust gas recirculation (EGR) passage coupled between the intake passage and the first exhaust manifold may be adjusted based on a pressure in the first exhaust manifold.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, one or more valves of a set of first exhaust valves coupled to the second exhaust manifold may be deactivated in response to select engine operating conditions, while maintaining active all valves of a set of second exhaust valves coupled to the first exhaust manifold. The select engine operating conditions may include one or more of a deceleration fuel shut-off condition, a part throttle condition, and a cold start condition.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a second exhaust manifold and exhaust gas to an exhaust passage via a first exhaust manifold. In one example, in response to an intake throttle being at least partially closed, intake air may be routed from the intake passage to the second exhaust manifold via an exhaust gas recirculation (EGR) passage where the intake air may be heated via an EGR cooler. The heated intake air may then be routed to an intake manifold, downstream of the intake throttle, via a flow passage coupled between the second exhaust manifold and the intake manifold.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, during a cold start, a method may include adjusting a position of a first valve disposed in an exhaust gas recirculation (EGR) passage based on an engine operating condition, the EGR passage coupled between the first exhaust manifold coupled to a first set of exhaust valves and the intake passage, upstream of a compressor. As one example, the engine operating condition may include an engine temperature or a temperature of a catalyst disposed in the exhaust passage.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, exhaust from a first set of exhaust valves coupled to the first exhaust manifold may be selectively routed to the intake passage via each of a first EGR passage coupled to the intake passage upstream of a compressor driven by a turbine and a second EGR passage coupled downstream of an outlet of the compressor. A decision of whether to route exhaust gas to the intake passage via the first EGR passage, second EGR passage, or both passages may be based on engine operating conditions.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, in response to flowing the exhaust gas recirculation and blowthrough air from the first exhaust manifold to the intake passage via a first set of exhaust valves, a first set of swirl valves coupled upstream of a first set of intake valves may be adjusted to at least partially block intake air flow to the first set of intake valves. Each engine cylinder may include two intake valves including one of the first set of intake valves and two exhaust valves.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, during a cold start, a method may include adjusting a position of a first valve disposed in an exhaust gas recirculation (EGR) passage based on an engine operating condition, the EGR passage coupled between the first exhaust manifold coupled to a first set of exhaust valves and the intake passage, upstream of a compressor. As one example, the engine operating condition may include an engine temperature or a temperature of a catalyst disposed in the exhaust passage.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, one or more valves of a set of first exhaust valves coupled to the second exhaust manifold may be deactivated in response to select engine operating conditions, while maintaining active all valves of a set of second exhaust valves coupled to the first exhaust manifold. The select engine operating conditions may include one or more of a deceleration fuel shut-off condition, a part throttle condition, and a cold start condition.

Abstract: Methods and systems are provided for controlling transitions between engine operating modes in a four-cylinder engine. One method includes transitioning engine operation between two-cylinder, three-cylinder, and four-cylinder modes wherein the transitioning includes a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals.

Abstract: Methods and systems are provided for controlling boost pressure and exhaust gas recirculation in a split exhaust system. In one example, a first portion of exhaust may be routed from a cylinder to an exhaust turbine via a first exhaust valve and a second, remaining portion of exhaust may be routed as exhaust gas recirculation (EGR) via a second exhaust valve, the timing and lift of each of the first valve profile and the second valve profile adjusted based on boost error and EGR error. Further, motor torque from an electric motor may be supplied to the turbocharger to attain a desired boost pressure and a desired EGR flow.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, a flow of exhaust (e.g., exhaust gas recirculation) from engine cylinders to the intake passage, upstream of a compressor, via an exhaust gas recirculation (EGR) passage and the first exhaust manifold may be adjusted by adjusting a timing of a first set of cylinder exhaust valves coupled to the first exhaust manifold. Additionally, the first set of cylinder exhaust valves open at a different time than a second set of cylinder exhaust valves coupled to the exhaust passage.