Systems, apparatus, and methods are disclosed that include a divided exhaust engine with at least one primary exhaust gas recirculation (EGR) cylinder and a plurality of non-primary EGR cylinders. The systems, apparatus and methods control the fueling to the at least one primary EGR cylinder in response to EGR fraction reduction conditions.

A method and a computer program for recognizing and differentiating a flow rate error and a dynamic error of an exhaust gas recirculation system (EGR) of an internal combustion engine. Measured and modeled EGR mass flow signals are each subjected to bandpass filtering using time constants optimized for determining flow rate errors and bandpass filtering using time constants optimized for determining dynamic errors. The energy is determined for each of the filtered signals and an energy quotient is computed between the energies of the signals filtered for dynamic errors and the signals filtered for flow rate errors. A dynamic error and a flow rate error of the exhaust gas recirculation may be recognized and differentiated from one another on the basis of the energy quotients.

Methods and systems are provided for controlling a turbocharged engine. In one example, a method may include concurrently adjusting an exhaust recirculation gas flow and a turbine flow while adjusting geometry of a compressor to compensate for disturbance caused by the compressor adjustment.

Methods and systems are provided for cleaning an exhaust particulate filter by routing air via the exhaust particulate filter during a vehicle-off condition. In one example, during vehicle-off conditions, a turbocharger may be reverse rotated via an electric motor or an engine may be reverse rotated via an electric machine to route air via the exhaust particulate filter and the soot collected from the particulate filter may then be deposited on an air filter coupled to the intake manifold. During a subsequent engine start, the soot from the intake air filter may be routed to the engine cylinders for combustion.

An engine system having an exhaust gas recirculation (EGR) apparatus includes: an engine including a plurality of combustion chambers; an intake line through which an intake gas supplied to the combustion chambers flows; an exhaust line in which an exhaust gas discharged from the combustion chambers flows; and a turbocharger including: a turbine disposed at the exhaust line and rotating by the exhaust gas; and a compressor disposed in the intake line and rotating and compressing external air. The EGR apparatus includes a recirculation line branched from the exhaust line; an EGR valve disposed at the recirculation line and adjusting a recirculation gas amount; a pressure sensor disposed at a front end of the EGR valve to measure a pressure of a recirculation gas; and a flow rate adjustment apparatus disposed at a rear end of the EGR valve and adjusting the recirculation gas amount.

Provided is a control device for an internal combustion engine, which can ensure a stable combustion state of the internal combustion engine even under a high-humidity environment condition, thereby improving the merchantability. The control device for the internal combustion engine includes an ECU (electronic control unit). The ECU calculates a basic target EGR amount according to an operating state of the internal combustion engine, calculates a water vapor amount in air drawn into an intake passage of the internal combustion engine, calculates an EGR conversion amount by using the water vapor amount, calculates a target EGR amount by subtracting the EGR conversion amount from the basic target EGR amount, and controls internal EGR and external EGR of the internal combustion engine by using the target EGR amount.

In a control device of an internal-combustion engine according to the disclosure, an intake throttle valve (25) for adjusting an EGR valve differential pressure (PEGR) is provided, an EGR valve upstream pressure (PEGR0) is estimated by using a target fresh air amount (GAIRCMD) (step 6), a target differential pressure (PEGRCMD) is set to a smaller value as the target fresh air amount (GAIRCMD) becomes smaller (FIG. 5), and a difference between the EGR valve upstream pressure (PEGR0) and the target differential pressure (PEGRCMD) is set as a target valve downstream pressure (P1CMD) (step 7). By using the target fresh air amount (GAIRCMD), the EGR valve upstream pressure (PEGR0), and the target valve downstream pressure (P1CMD), the target EGR valve opening degree (LEGRCMD) is set (step 23), and an EGR valve (43) is controlled based on the target EGR valve opening degree (step 24).

An internal combustion engine includes an intercooler configured to cool an intake gas compressed by a compressor, a cooler bypass passage configured to bypass the intercooler, and a cooler bypass valve configured to open and close the cooler bypass passage, and an exhaust gas recirculation gas is introduced into an upstream side of the intercooler. An electronic control unit is configured to open the cooler bypass valve during use of a high exhaust gas recirculation rate region, and to close the cooler bypass valve during use of a low exhaust gas recirculation rate region.

A method and a computer program for recognizing and differentiating a flow rate error and a dynamic error of an exhaust gas recirculation system (EGR) of an internal combustion engine. Measured and modeled EGR mass flow signals are each subjected to bandpass filtering using time constants optimized for determining flow rate errors and bandpass filtering using time constants optimized for determining dynamic errors. The energy is determined for each of the filtered signals and an energy quotient is computed between the energies of the signals filtered for dynamic errors and the signals filtered for flow rate errors. A dynamic error and a flow rate error of the exhaust gas recirculation may be recognized and differentiated from one another on the basis of the energy quotients.

A control system and a control method for an internal combustion engine, which are capable of accurately calculating an in-cylinder gas amount and an EGR ratio by a relatively simple method even in a case where an in-cylinder gas temperature is changed by execution of internal EGR, and properly controlling the engine using the EGR ratio thus calculated. An in-cylinder gas amount Gact actually filled in the cylinder is calculated by correcting an ideal in-cylinder gas amount Gth, which is an amount of gases filled in a cylinder in an ideal state in which it is assumed that no exhaust gases of the engine are recirculated into the cylinder, using an ideal in-cylinder gas temperature Tcylth according to an in-cylinder gas temperature Tcyl, and an EGR ratio REGRT is calculated using the in-cylinder gas amount Gact and an intake air amount Gaircyl.