An engine system incorporating an engine, one or more sensors, and a controller. The controller may be connected to the one or more sensors and the engine. The one or more sensors may be configured to sense one or more parameters related to operation of the engine. The controller may incorporate an air-path state estimator configured to estimate one or more air-path state parameters in the engine based on values of one or more parameters sensed by the sensors. The controller may have an on-line and an off-line portion, where the on-line portion may incorporate the air-path state estimator and the off-line portion may configure and/or calibrate a model for the air-path state estimator.

The present disclosure relates to improvements in turbocharger efficiency and more particularly to a method and system for estimating the efficiency loss of a turbocharger. The method comprises the steps of monitoring a plurality of operating parameters and determining a compressor exit temperature according to a first calibration map based on these operating parameters. An estimate of instantaneous turbocharger efficiency loss according to a second calibration map is then determined, based on the compressor exit temperature. The instantaneous turbocharger efficiency loss is used to determine an estimate of cumulative turbocharger efficiency loss during engine service. The estimate of cumulative turbocharger efficiency loss is compared with a first predetermined efficiency loss threshold and a first signal is generated if the first predetermined efficiency loss threshold is exceeded.

The invention relates to a method for modeling a compressor intake temperature and/or a compressor discharge temperature of a compressor taking into account a compressor surge, wherein the method comprises: Identifying a pressure gradient across the compressor Identifying a mass flow gradient across the compressor Establishing that the compressor surge is present when the pressure gradient exceeds an upper pressure gradient limit and the mass flow gradient falls below a lower mass flow gradient limit; and Identifying the compressor intake temperature with a temperature correction factor that is dependent on the compressor surge and/or identifying the compressor discharge temperature on the basis of a corrected compressor discharge pressure that is dependent on the compressor surge.

Examples of the present disclosure describe systems and methods for determining an estimated ambient air temperature in an environment in which a vehicle is operating. The estimated ambient air temperature may be compared to an ambient temperature sensor value. The comparison may be used to determine whether an ambient air temperature sensor of the vehicle is functioning properly or if an error notification or fault code should be triggered.

The invention relates to a method for modeling a compressor intake temperature and/or a compressor discharge temperature of a compressor taking into account a compressor surge, wherein the method comprises: Identifying a pressure gradient across the compressor Identifying a mass flow gradient across the compressor Establishing that the compressor surge is present when the pressure gradient exceeds an upper pressure gradient limit and the mass flow gradient falls below a lower mass flow gradient limit; and Identifying the compressor intake temperature with a temperature correction factor that is dependent on the compressor surge and/or identifying the compressor discharge temperature on the basis of a corrected compressor discharge pressure that is dependent on the compressor surge.

Examples of the present disclosure describe systems and methods for determining an estimated ambient air temperature in an environment in which a vehicle is operating. The estimated ambient air temperature may be compared to an ambient temperature sensor value. The comparison may be used to determine whether an ambient air temperature sensor of the vehicle is functioning properly or if an error notification or fault code should be triggered.

Examples of the present disclosure describe systems and methods for determining a state of an air diverter valve of an air induction system of a vehicle. The determined state of the air diverter valve may be based on an intercooler-based estimated ambient air temperature and a comparison between an ambient air temperature sensor value and a pre-compressor sensor value.

An intake air temperature estimation system includes: an adiabatically compressed intake air temperature computing unit that computes an adiabatically compressed intake air temperature based on an intake air temperature before compression, an intake air pressure before compression and an intake air pressure after compression; and an estimated intake air temperature computing unit that computes an estimated intake air temperature. The estimated intake air temperature computing unit variably sets a coefficient of the function in response to an amount of change per unit time in the intake air pressure after compression such that a followability of the estimated intake air temperature to the adiabatically compressed intake air temperature at the time when the amount of change is large is higher than a followability of the estimated intake air temperature to the adiabatically compressed intake air temperature at the time when the amount of change is small.

An engine system incorporating an engine, one or more sensors, and a controller. The controller may be connected to the one or more sensors and the engine. The one or more sensors may be configured to sense one or more parameters related to operation of the engine. The controller may incorporate an air-path state estimator configured to estimate one or more air-path state parameters in the engine based on values of one or more parameters sensed by the sensors. The controller may have an on-line and an off-line portion, where the on-line portion may incorporate the air-path state estimator and the off-line portion may configure and/or calibrate a model for the air-path state estimator.

Examples of the present disclosure describe systems and methods for determining a state of an air diverter valve of an air induction system of a vehicle. The determined state of the air diverter valve may be based on an intercooler-based estimated ambient air temperature and a comparison between an ambient air temperature sensor value and a pre-compressor sensor value.