Methods and systems are provided for an auto-ignition internal combustion engine comprising an exhaust gas recirculation arrangement, an intake system, and an exhaust gas discharge system for the discharge of exhaust gases, in which the internal combustion engine is operable, at least in a first, stoichiometric operating mode, by way of a spatial ignition method (HCCI mode). For the aftertreatment of the exhaust gas in the first operating mode, a three-way catalytic converter is provided in the exhaust gas discharge system for reducing nitrogen oxides and oxidizing unburned hydrocarbons and carbon monoxide. In this way, the auto-ignition internal combustion engine has a greater window of operation in the HCCI mode than conventional auto-ignition internal combustion engines.

Methods and systems are provided for an auto-ignition internal combustion engine comprising an exhaust gas recirculation arrangement, an intake system, and an exhaust gas discharge system for the discharge of exhaust gases, in which the internal combustion engine is operable, at least in a first, stoichiometric operating mode, by way of a spatial ignition method (HCCI mode). For the aftertreatment of the exhaust gas in the first operating mode, a three-way catalytic converter is provided in the exhaust gas discharge system for reducing nitrogen oxides and oxidizing unburned hydrocarbons and carbon monoxide. In this way, the auto-ignition internal combustion engine has a greater window of operation in the HCCI mode than conventional auto-ignition internal combustion engines.

A hybrid vehicle may include an engine; a turbocharger including a turbine disposed in an exhaust line and a compressor; an electric supercharger disposed in the intake line at an upstream portion of the compressor; an exhaust gas post processing apparatus; a low pressure EGR device which includes a low pressure EGR line, a low pressure EGR cooler and a low pressure EGR valve; an intake bypass line which connects the intake line at a downstream portion of the electric supercharger and the intake line at an upstream portion of the electric supercharger; an intake bypass valve disposed in the intake bypass line; a post processing bypass line which connects the intake line between the electric supercharger and the compressor and the exhaust line between the turbine and the exhaust gas post processing apparatus; and a post processing bypass valve disposed in the post processing bypass line.

A hybrid vehicle may include an engine; a turbocharger including a turbine disposed in an exhaust line and a compressor; an electric supercharger disposed in the intake line at an upstream portion of the compressor; an exhaust gas post processing apparatus; a low pressure EGR device which includes a low pressure EGR line, a low pressure EGR cooler and a low pressure EGR valve; an intake bypass line which connects the intake line at a downstream portion of the electric supercharger and the intake line at an upstream portion of the electric supercharger; an intake bypass valve disposed in the intake bypass line; a post processing bypass line which connects the intake line between the electric supercharger and the compressor and the exhaust line between the turbine and the exhaust gas post processing apparatus; and a post processing bypass valve disposed in the post processing bypass line.

Exhaust gas recirculation systems and methods are provided for an internal combustion engine. The system includes a first conduit configured to receive at least a portion of exhaust gas from the internal combustion engine; a cooling circuit selectively fluidly coupled to the first conduit; a bypass circuit selectively fluidly coupled to the first conduit and including a bypass conduit; and a second conduit fluidly coupled to receive the exhaust gas flowing through the cooling circuit and through the bypass circuit. A cooling valve has a bypass position to direct the exhaust gas from the first conduit through the bypass circuit, a cooling position to direct the exhaust gas from the first conduit through the cooling circuit, and a closed position to prevent the exhaust gas from flowing into either of the bypass or cooling circuits. The system further includes a heating device for selectively heating the bypass conduit.

Exhaust gas recirculation systems and methods are provided for an internal combustion engine. The system includes a first conduit configured to receive at least a portion of exhaust gas from the internal combustion engine; a cooling circuit selectively fluidly coupled to the first conduit; a bypass circuit selectively fluidly coupled to the first conduit and including a bypass conduit; and a second conduit fluidly coupled to receive the exhaust gas flowing through the cooling circuit and through the bypass circuit. A cooling valve has a bypass position to direct the exhaust gas from the first conduit through the bypass circuit, a cooling position to direct the exhaust gas from the first conduit through the cooling circuit, and a closed position to prevent the exhaust gas from flowing into either of the bypass or cooling circuits. The system further includes a heating device for selectively heating the bypass conduit.

An internal combustion engine has an exhaust gas recirculation system for recirculating exhaust gases from the internal combustion engine into an intake region of the internal combustion engine. The exhaust gas recirculation system includes the following components: at least one exhaust gas cooler through which a first flow path for recirculating exhaust gas extends, having at least one first cooling stage and at least one additional cooling stage, at least one flap arrangement by which the at least one additional cooling stage can be connected, a bypass line through which a second flow path for recirculating exhaust gas extends and by which the exhaust gas cooler can be bypassed during the recirculation of exhaust gas, and an EGR valve having at least three possible positions.

An internal combustion engine has an exhaust gas recirculation system for recirculating exhaust gases from the internal combustion engine into an intake region of the internal combustion engine. The exhaust gas recirculation system includes the following components: at least one exhaust gas cooler through which a first flow path for recirculating exhaust gas extends, having at least one first cooling stage and at least one additional cooling stage, at least one flap arrangement by which the at least one additional cooling stage can be connected, a bypass line through which a second flow path for recirculating exhaust gas extends and by which the exhaust gas cooler can be bypassed during the recirculation of exhaust gas, and an EGR valve having at least three possible positions.

An engine exhaust gas circuit includes a primary circuit in fluid communication with an intake of an engine and an outlet of the engine. The primary circuit conveys a gas from the outlet of the engine to the inlet of the engine. The primary circuit including a valve body having a rotary flap rotatably disposed in the valve body. A bypass circuit extends from a branch point intermediate the outlet of the engine and the valve body to the valve body.

An internal combustion engine includes an intercooler configured to cool an intake gas compressed by a compressor, a cooler bypass passage configured to bypass the intercooler, and a cooler bypass valve configured to open and close the cooler bypass passage, and an exhaust gas recirculation gas is introduced into an upstream side of the intercooler. An electronic control unit is configured to open the cooler bypass valve during use of a high exhaust gas recirculation rate region, and to close the cooler bypass valve during use of a low exhaust gas recirculation rate region.