Methods for protecting turbochargers of engine systems include determining a speed gradient of the turbocharger and implementing a turbocharger speed protection action if the determined speed gradient is above a speed gradient threshold. Implementing a protection action comprises limiting engine torque, engine speed, vehicle speed, and/or fuel injection to the engine. The method can further include determining a cold start condition prior to determining the speed gradient of the turbocharger. A cold start condition can be determined based on ambient temperature, engine oil temperature, or engine coolant temperature. The method can further include, subsequent to implementing the turbocharger speed protection action, disabling the turbocharger speed protection action when a subsequently determined turbocharger speed gradient is below the speed gradient threshold. Systems for implementing the methods are also disclosed.

A method of detecting surging in a turbocharger provided for an internal combustion engine, includes: a first characteristic quantity calculation step of calculating a first characteristic quantity in at least one first frequency region corresponding to at least one first peak frequency component unique to the time of occurrence of surging in the turbocharger on the basis of a time-variable waveform indicating a time-series change of a rotation speed of the turbocharger; a second characteristic quantity calculation step of calculating a second characteristic quantity in a second frequency region including the at least one first frequency region on the basis of the time-variable waveform; and a detection step of detecting surging in the turbocharger on the basis of a relationship between the first characteristic quantity and the second characteristic quantity. The second frequency region further includes at least one second peak frequency unique to the time of acceleration and deceleration of the internal combustion engine from among frequency components different from the at least one first peak frequency component.

A turbocharged device including a turbocharger, a first sensor in operable communication with the turbocharger and configured to output a first signal representative of a first attribute of the turbocharger, and a controller in operable communication with the first sensor. Where the controller is configured to calculate a first preliminary surge score based at least in part on the first signal, and calculate a first weighted surge score based at least in part on the first preliminary surge score and a first weighting factor configured to express the relative significance of the first preliminary surge score.

A system for real-time modeling includes a compressor designed to operate at a compressor speed, a compressor flow rate, and a compressor pressure ratio. The system also includes a memory designed to store an operating condition matrix that plots multiple compressor pressure ratios to each of a plurality of compressor speeds, and a related operating state matrix that plots multiple compressor flow rates to each of the plurality of compressor speeds. The system also includes a compressor controller to determine a target compressor speed and a target compressor pressure ratio, and to identify a target location in the operating condition matrix based on the target compressor speed and the target compressor pressure ratio. The compressor controller also determines a target compressor flow rate by interpolating values in the operating state matrix based on the target location, and to control the compressor based on the target compressor flow rate.

Methods and systems are provided for improving surge control in a boosted engine system configured with an electric motor to provide electrical boost assistance. Tip-in and tip-out surge are addressed by increasing the opening of a compressor recirculation valve and coordinating the recirculation valve opening with adjustments to an exhaust waste-gate position and a power output by the electric motor. The adjustments enable an intake airflow to be provided that operates the compressor outside a surge region while providing a target boost pressure as operator torque demand increases or decreases.

An engine system incorporating an intake manifold, a compressor, and a controller. The compressor may provide air to the intake manifold and the controller may be connected to the intake manifold and the compressor. The controller may receive a control signal and control air flow from the compressor to the intake manifold based on the received control signal. The controller may control the air flow from the compressor to the intake manifold based on a first equation when a value related to the control signal is on a first side of a threshold and according to a second equation when the value is on a second side of the threshold. The controller may control the air flow between the compressor and intake manifold according to the second equation to prevent the compressor from operating at a surge condition when controlling the air flow according to the first equation.

Methods and systems are provided for a variable inlet device of a compressor. In one example, a compressor may include an impeller rotatable about a central axis and an inlet conduit including a variable inlet device (VID) positioned upstream of the impeller and adjustable between and open position and a closed position that restricts and generates pre-swirl flow to the impeller. The VID may include a plurality of adjacently arranged blades forming a ring around the central axis with inner surfaces of the blades forming a flow passage through the VID, each of the blades being pivotable, about an axis arranged tangent to the ring, between the open and closed position.

Methods and systems are provided for an engine system configured with a wide range active compressor and high pressure EGR. In one example, a compressor may include an active casing treatment with a slideable sleeve may be adjusted to direct air flow through either a choke slot and surge slot to control compressor efficiency, thereby maintaining EGR flow. In another example, the compressor may comprise a variable inlet device to regulate air flow through the compressor, thereby adjusting compressor efficiency and also maintaining EGR flow.

A turbocharged device subject to a surge event during operation, the turbocharged device including a turbocharger having a controller and a bearing assembly, a first sensor configured to detect the oil pressure provided to the bearing assembly, a second sensor in operable communication with the turbocharger, where the controller is configured to determine the magnitude of the surge event based at least in part on a signal provided by the second sensor in response to the surge event, and where the controller is configured to determine the wear inflicted on the turbocharger during the surge event based at least in part on the magnitude of the surge event and a signal provided by the first sensor in response to the surge event.

Methods and systems are provided for a slidable sleeve valve actuation system for a turbocharger compressor. In one example, an actuator assembly for a slidable sleeve of a turbocharger compressor may comprise: a fork arm coupled to the slidable sleeve; a rotatable lever arm coupled to the fork arm via a rigid connecting shaft; a connector rod coupled between the lever arm and a rotatable element; and an actuator unit coupled to the rotatable element and attached to an attachment case, the attachment case coupled to the turbocharger compressor. The actuator assembly may be actuated to move the slidable sleeve from one position along a casing treatment to another position along the casing treatment, thereby adjusting the alignment of sleeve slots on the slidable sleeve relative to choke or surge slots on the casing treatment.