A smooth shift is achieved between an operating region in which a first turbocharger is mainly operated and an operating region in which a second turbocharger is mainly operated. A PCM controls a throttle valve to use a first supercharging region in which a gas flow through an exhaust bypass passage is reduced and a second supercharging region in which the gas flow through the exhaust bypass passage is promoted differently based on the operating state of an engine. In an early stage of a shift from the first supercharging region to the second supercharging region, the PCM executes bridge control to allow the flow velocity of exhaust gas flowing into a large turbine to be higher than at a point in time at which the shift starts.

Methods and systems are provided for providing torque reserve via an electrically assisted turbocharger. A portion of requested torque reserve is provided by intentionally reducing turbine speed of an electric turbocharger by operating the associated electric motor as a generator. The resulting reduction in air mass allows for the torque reserve to be provided with reduced reliance on spark and throttle based torque reserve.

Methods and systems are provided for coordinated operation of electric variable geometry turbocharger (e-VGT), an exhaust gas recirculation (EGR), and electric motor coupled to the e-VGT for expedited catalyst light-off. In one example, a method may include, during a cold-start, decreasing each of an opening of e-VGT vanes and an opening of an EGR valve while operating the electric motor for braking and reducing the e-VGT speed.

An object is to provide a supercharging system capable of actively and easily controlling a rotational speed of a turbine generator. A supercharging system includes a compressor driven by an electric motor to pump fluid to an engine, a turbine generator rotated by exhaust from the engine, and a drive device that drives the electric motor by electricity generated by the turbine generator, wherein the drive device includes a rectifying unit that rectifies the electricity generated by the turbine generator, a converter unit that steps up or down a voltage value of a DC voltage rectified by the rectifying unit and outputs the DC voltage, an inverter unit that drives the electric motor using the DC voltage output from the converter unit, and a control unit that controls a change amount of the DC voltage in the converter unit.

A control apparatus of a supercharging system for supplying an engine with compressed intake air, includes: a supercharger including a compressor configured to compress the intake air to be supplied to the engine; and a controller for controlling a control device affecting operation of the compressor. The controller includes: a compressor map storage part configured to store a compressor map which indicates a relationship of an intake volume flow rate, a pressure ratio, and a compressor rotation speed in the compressor; a current position calculation part configured to calculate a current position of an operational point of the compressor on the compressor map every predetermined period; a moving direction calculation part configured to calculate a moving direction of the operational point on the compressor map on the basis of the current position of the operational point calculated by the current position calculation part; and a control part configured to control the control device on the basis of the current position of the operational point calculated by the current position calculation part and the moving direction of the operational point calculated by the moving direction calculation part.

Methods and systems are provided for controlling boost pressure in a staged engine system comprising a turbocharger and an upstream electric supercharger. In one example, a method may include coordinating the operation of the electric supercharger and an electric supercharger bypass valve and to open the electric supercharger bypass valve to reduce the extent and duration of electric supercharger overboost.

A turbocharger system includes a valve member disposed between plural volute passages of a turbine section and a wastegate. The valve member is supported for rotation about an axis of rotation between various positions. The valve member, in a first position, provides a cross flow path between the first volute passage and the second volute passage and provides a bypass flow path from at least one of the first and second volute passages to the wastegate. In a second position, the valve member provides the cross flow path and substantially prevents flow along the bypass flow path. In a third position, the valve member substantially prevents flow along the cross flow path and the bypass flow path. The valve member includes at least internal one valve passage and plural apertures that fluidly connect or alternatively fluidly disconnect the volute passages and wastegate in the first, second, and third positions.

The invention relates to a method of controlling engine derating of an internal combustion engine (10) being provided with a turbocharger (110) and a variable inlet guide vanes assembly (130) arranged upstream a compressor (120) of the turbocharger (110). The method comprises determining a current operational condition requiring engine derating, detecting a current operational condition of the compressor (120), and controlling the position of the variable inlet guide vanes assembly (130) based on the detected operational condition of the compressor (120).

A power unit for use with an internal combustion engine including a compressor housing, a compressor wheel positioned within and rotatable with respect to the compressor housing, a shaft coupled to the compressor wheel and rotatable together therewith, a motor assembly in operable communication with the shaft, and a controller in operable communication with the motor assembly. Where the controller is adjustable between a first mode of operation, in which the motor assembly applies torque to the shaft in a first direction of rotation, and a second mode of operation, in which the motor assembly unit applies torque to the shaft in a second direction of rotation opposite the first direction of rotation.

An internal combustion engine including a block, a head coupled to the block to at least partially define a cylinder therebetween, and a compressor assembly having an inlet and an outlet in fluid communication with the cylinder. Where the compressor is operable in a first mode, in which a first portion of the gasses exiting the outlet are directed to the cylinder and a second portion of the gasses exiting the outlet is recirculated back to the inlet