An engine system may include an engine including a plurality of combustion chambers generating driving torque by combustion of fuel, an intake line through which outside air supplied to the combustion chamber flows, an exhaust line for exhausting the exhaust gas from the combustion chamber to the outside, a turbocharger including a compressor mounted in the intake line and a turbine mounted in the exhaust line, an air supply passage through which a portion of the outside air branched from the intake line and supplied to the combustion chamber, an air supply nozzle connected to the air supply passage and supplying the part of the outside air to the combustion chamber, an air supply pump provided in the air supply passage and providing an injection pressure to the part of the outside air injected into the combustion chamber, and a controller for controlling the air supply nozzle and the air supply pump.

An engine system may include an engine including a plurality of combustion chambers generating driving torque by combustion of fuel, an intake line through which outside air supplied to the combustion chamber flows, an exhaust line for exhausting the exhaust gas from the combustion chamber to the outside, a turbocharger including a compressor mounted in the intake line and a turbine mounted in the exhaust line, an air supply passage through which a portion of the outside air branched from the intake line and supplied to the combustion chamber, an air supply nozzle connected to the air supply passage and supplying the part of the outside air to the combustion chamber, an air supply pump provided in the air supply passage and providing an injection pressure to the part of the outside air injected into the combustion chamber, and a controller for controlling the air supply nozzle and the air supply pump.

An engine system may include an engine including a plurality of combustion chambers generating driving torque by combustion of fuel, an intake line through which outside air supplied to the combustion chamber flows, an exhaust line for exhausting the exhaust gas from the combustion chamber to the outside, a turbocharger including a compressor mounted in the intake line and a turbine mounted in the exhaust line, an air supply passage through which a portion of the outside air branched from the intake line and supplied to the combustion chamber, an air supply nozzle connected to the air supply passage and supplying the part of the outside air to the combustion chamber, an air supply pump provided in the air supply passage and providing an injection pressure to the part of the outside air injected into the combustion chamber, and a controller for controlling the air supply nozzle and the air supply pump.

A downhole power generation system is disclosed, which includes a power generation module for providing power to a load, comprising a turbine driven by flow of a downhole fluid to rotate, a generator coupled with the turbine for converting rotational energy from the turbine to electrical energy, and an AC-DC rectifier coupled with the generator for converting an alternating current voltage from the generator to a direct current voltage, and a power conversion circuit coupling the AC-DC rectifier with the load. The power conversion circuit is configured for providing a first power to the load when the load is in a working mode and providing a second power to the load when the load is in a non-working mode. The second power is less than the first power. A downhole power generation method is also disclosed.

A generator system may include a compressor and an electric motor. The compressor includes an impeller, and the compressor provides a quantity of air flowing toward an intake of an engine through rotation of the impeller. The electric motor is mechanically linked to the compressor and rotates the impeller to force the quantity of air flowing toward the intake of the engine. The generator system may include a charge air cooler to receive the quantity of air flowing toward the intake of the engine and increase an air charge density of the quantity of air. The generator system may include an exhaust portion to expel exhaust from the engine such that the quantity of air provided by the compressor does not include exhaust expelled by the exhaust portion. The generator system may include an air valve configured to regulate the quantity of air flowing toward the intake of the engine.

A valve arrangement for supplying air to a combustion chamber of an internal combustion engine includes a first valve, the first valve including a first valve head, a first valve stem assembly and an internal cavity, which is at least partly located in the first valve stem assembly, and a second valve partly arranged within the internal cavity of the first valve, the second valve including a second valve head and a second valve stem assembly, and being movable within the internal cavity between an upper, closed position and a lower, open position, wherein a junction seal extends over a junction between the first valve stem assembly and the second valve stem assembly when the second valve is in the closed position. A leakage preventing arrangement is arranged to hinder leakage of liquid from the outside of the junction seal from reaching in between the first valve stem assembly and the second salve stem assembly.

A valve arrangement for supplying air to a combustion chamber of an internal combustion engine includes a first valve, the first valve including a first valve head, a first valve stem assembly and an internal cavity, which is at least partly located in the first valve stem assembly, and a second valve partly arranged within the internal cavity of the first valve, the second valve including a second valve head and a second valve stem assembly, and being movable within the internal cavity between an upper, closed position and a lower, open position, wherein a junction seal extends over a junction between the first valve stem assembly and the second valve stem assembly when the second valve is in the closed position. A leakage preventing arrangement is arranged to hinder leakage of liquid from the outside of the junction seal from reaching in between the first valve stem assembly and the second salve stem assembly.

One variation may include a method of controlling exhaust gas flow in an internal combustion engine system, and products and systems using same.

One variation may include a method of controlling exhaust gas flow in an internal combustion engine system, and products and systems using same.

An internal combustion engine includes a turbocharger, a variable valve gear, an A/F sensor in an exhaust passage, A/F feedback control means, and scavenge A/F control means. The variable valve gear drives intake and exhaust valves, and can drive with a valve open characteristic with valve overlap. The A/F feedback control means performs feedback correction of a fuel injection amount based on an A/F sensor output, and acquires a learning value of information relating to A/F control from a feedback correction amount. The scavenge A/F control means carries out A/F control by a value learned during an operation of the engine with non-scavenge valve open characteristic, when the variable valve gear is operated with the scavenge valve open characteristic. The scavenge valve open characteristic has a valve overlap amount of such a degree that blow-by of intake air occurs in an intake stroke during a turbocharger operation.