Abstract: An engine assembly comprises an exhaust gas recirculation circuit, an aftertreatment apparatus and a controller. The controller is configured to determine a desired proportion of exhaust gas to be directed to the exhaust gas recirculation circuit. The controller is further configured to determine, based on the proportion of exhaust gas to be directed to the exhaust gas recirculation circuit, a baseline value for an extent to which to open the exhaust gas recirculation valve for a clean aftertreatment apparatus. The controller is further configured to determine a compensation function based on an inferred aftertreatment flow restriction value. The controller is further configured to control the extent to which the exhaust gas recirculation valve is open based on the baseline value modified by the compensation function in order to maintain the desired proportion of exhaust gas to be directed to the exhaust gas recirculation circuit.

Abstract: An engine assembly comprises an exhaust gas recirculation circuit, an aftertreatment apparatus and a controller. The controller is configured to determine a desired proportion of exhaust gas to be directed to the exhaust gas recirculation circuit. The controller is further configured to determine, based on the proportion of exhaust gas to be directed to the exhaust gas recirculation circuit, a baseline value for an extent to which to open the exhaust gas recirculation valve for a clean aftertreatment apparatus. The controller is further configured to determine a compensation function based on an inferred aftertreatment flow restriction value. The controller is further configured to control the extent to which the exhaust gas recirculation valve is open based on the baseline value modified by the compensation function in order to maintain the desired proportion of exhaust gas to be directed to the exhaust gas recirculation circuit.

Abstract: An electric assist turbocharger unit for use in an internal combustion engine, comprising a shaft configured for torque-transmittingly connecting a compressor to a turbine of the turbocharger unit and an electric motor configured for rotatably actuating the shaft in a first rotational direction and in an opposed second rotational direction. The engine includes an aftertreatment system, and the rotation of the shaft is designed to retard the flow of intake air through an intake passage and of exhaust gases through the aftertreatment system, thereby controlling the temperature in the aftertreatment system.

Abstract: An electric assist turbocharger unit for use in an internal combustion engine, comprising a shaft configured for torque-transmittingly connecting a compressor to a turbine of the turbocharger unit and an electric motor configured for rotatably actuating the shaft in a first rotational direction and in an opposed second rotational direction. The engine includes an aftertreatment system, and the rotation of the shaft is designed to retard the flow of intake air through an intake passage and of exhaust gases through the aftertreatment system, thereby controlling the temperature in the aftertreatment system.

Abstract: A method of calibrating a soot load estimating function for a diesel particulate filter uses radio frequency attenuation measurement and temperature measurements. The method comprises identifying a minimum mean attenuation value associated with a standard deviation that exceeds a standard deviation threshold and using this minimum mean attenuation value as a reference value. The method further comprises using a data library that contains gradient values for each of a range of possible temperature values to obtain a first gradient value, the first gradient value corresponding to the first temperature value, wherein each gradient value relates to the gradient of a linear approximation between mean attenuation and soot load at the corresponding temperature. The method involves using the reference value and the first gradient value to determine an axis intercept value for use as an offset value and adopting the offset value as a temperature-independent calibration value for the diesel particulate filter.

Abstract: A method of calibrating a soot load estimating function for a diesel particulate filter uses radio frequency attenuation measurement and temperature measurements. The method comprises identifying a minimum mean attenuation value associated with a standard deviation that exceeds a standard deviation threshold and using this minimum mean attenuation value as a reference value. The method further comprises using a data library that contains gradient values for each of a range of possible temperature values to obtain a first gradient value, the first gradient value corresponding to the first temperature value, wherein each gradient value relates to the gradient of a linear approximation between mean attenuation and soot load at the corresponding temperature. The method involves using the reference value and the first gradient value to determine an axis intercept value for use as an offset value and adopting the offset value as a temperature-independent calibration value for the diesel particulate filter.

Abstract: Method and system for controlling the temperature dependent mode of an exhaust after treatment device, EATD, within an engine system comprising: identifying a target EATD mode. Regulating an EATD temperature to within a temperature range corresponding with the target mode by controlling a gas pressure difference of the engine system between a first location and a second location.