A method of operating an internal combustion engine, wherein the internal combustion engine has at least one combustion engine, a fresh gas line, and a compressor integrated in the gas line, which is associated with a trim controller, via which an edge-side portion of the inlet cross section of a compressor impeller of the compressor is coverable to a variable extent. In this case, in a release position of the trim controller, the edge-side portion of the inlet cross section is covered relatively little, and in a covering position of the trim controller, is mostly covered. It is provided that in a transition from a traction mode of the combustion engine, in which the trim controller is in the release position, the trim controller is adjusted to an overrun mode of the combustion engine into the covering position. As a result, a so-called discharge hissing can be prevented or minimized.

A control system and method for an engine including a turbocharger without a surge valve involve utilizing one or more pressure sensors configured to measure air pressure in an intake system of the engine, the intake system comprising a compressor of the turbocharger and a throttle valve downstream from the compressor, and a controller configured to control the engine to avoid surge at the compressor and eliminate a need for the surge valve by determining a desired position for the throttle valve based on a driver requested engine torque, determining a minimum mass flow through the compressor that avoids surge based on the measured air pressure in the intake system and a predetermined compressor map, and commanding the throttle valve to a target position to maintain at least the minimum compressor mass flow, wherein the target position is greater than the desired position, thereby avoiding surge at the compressor.

A supercharger device for an internal combustion engine, including an exhaust gas turbocharger and a recuperation charger having a compressor turbine and an electromechanical motor-generator coupled thereto. The compressor turbine is connectable on the low-pressure side thereof to a charge air supply line and on the high-pressure side of the compressor turbine to both the charge air supply line and an exhaust gas tract of the engine. The recuperation charger is able to be switched at least between a booster operative mode and a recuperation operative mode. The recuperation charger may be operated as a compressor driven by the motor-generator for increasing pressure in the charge air supply line in the booster operative mode, or driven by at least a portion of a charge air mass flow, the exhaust gas mass flow, or both, and operated as a turbine so as to recover energy by the motor-generator.

A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a plurality of vanes formed as ring segments and disposed about the air inlet and each movable circumferentially and radially inwardly through a slot in the air inlet wall so as to form an orifice of reduced diameter relative to a nominal diameter of the inlet. Movement of the inlet-adjustment mechanism from the open position to the closed position is effective to shift the compressor's surge line to lower flow rates.

The present invention relates to a method for controlling the amount of air fed to the intake of a turbocharged internal-combustion engine, comprising an intake manifold (18) and at least one exhaust gas outlet (28; 28, 28) connected to an exhaust manifold (26; 26, 26). The engine comprises a turbocharger (30) with a turbine (32) having at least one inlet (34; 34, 34) connected to said at least one exhaust gas outlet and with an outside air compressor (38), and at least one turbine speed amplifier circuit (Boost) with at least one transfer line (54; 54, 54) for transferring the compressed air from the compressor to the turbine inlet and controlled by throttling means (58; 58, 58). According to the invention, to be fed to the turbine through the amplifier circuit (Boost) the theoretical flow rate (Qair obj) is known, the air flow rate (Qair mes) is estimated, the two flow rates are compared, and a difference between the two flow rates, is controlled to correspond to the theoretical air flow rate.

In cases where an EGR device is provided in which an EGR gas is recirculated to an upstream side of a compressor, the generation of condensed water is suppressed in an intake passage at the downstream side of the compressor. In the case where the temperature of a wall surface of the intake passage estimated or detected by a temperature detector is equal to or less than a predetermined temperature, a rotational speed of a turbine is made higher than in the case where the estimated or detected temperature of the wall surface of the intake passage is higher than the predetermined temperature, and torque of an internal combustion engine is adjusted such that an amount of change in an output of the internal combustion engine at the time of the rotational speed of the turbine being thus made higher falls within a predetermined range.

A method for controlling an inlet-adjustment mechanism in an air inlet for a compressor so as to switch the mechanism between open and closed positions for adjusting a flow area of the inlet. The method includes an algorithm for determining when the inlet-adjustment mechanism is in a failure mode. In accordance with the method, when the operating point on the compressor map is on the high-flow side of a threshold line at which the inlet-adjustment mechanism is switched from one position to the other, a measured speed or pressure ratio is compared to a theoretical value for the speed or pressure ratio based on a compressor map for the open position of the mechanism. If the measured value differs from the theoretical value by more than a predetermined tolerance, a failure mode is indicated.

According to the present invention, the impeller inlet of a turbocharger compressor receives intake air from an inner channel and an outer channel. The outer channel is pressurized with an electrically powered secondary compressor. The pressurized air in the outer channel flows into the impeller near the outer wall of the impeller inlet. The pressurized air next to the outer wall of the impeller inlet prevents backflow of air out of the impeller and thereby prevents surge and enables the compressor to produce high boost pressures under small mass flow settings. Only a portion of the intake air is pressurized with the electrically powered secondary compressor, and the boost pressure of the electrical compressor is only a fraction of the turbocharger compressor's overall pressure ratio. Consequently, only a small amount of electrical power is required to drive the secondary compressor, thereby enabling conventional 12 volt batteries to be used to power the electrical compressor for almost all automotive applications.

A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a plurality of blades disposed about the air inlet and each pivotable about one end of the blade, the blades extending through a slot in the air inlet wall when the blades are in the closed position so as to form an orifice of reduced diameter relative to a nominal diameter of the inlet. Movement of the inlet-adjustment mechanism from the open position to the closed position is effective to shift the compressor's surge line to lower flow rates.

The present invention is a device for controlling a quantity of air introduced into an inlet of a boosted internal combustion engine with the engine having exhaust gas outlets each connected to an exhaust manifold of at least one cylinder. The device includes a boosting device comprising a turbocharger having a turbine with intakes connected to the exhaust gas outlets, an external-air compressor and a duct for partially transferring the compressed air from the compressor to the intakes. The partial transfer duct has branches connected to the turbine intakes which each have a regulator valve for controlling circulation of compressed air in the branches.