Abstract: Engine low pressure cooled exhaust gas recirculation (LPCEGR) control techniques comprise receiving a measured position of an accelerator pedal and, based on this measurement, detecting a transient tip-out event or a transient tip-in event. In response to detecting the transient tip-out event, an EGR depletion rate is temporarily increased by at least one of (i) downstream throttle valve control to maintain at least a minimum engine airflow or to regulate a rate of decrease of the airflow into the engine, (ii) cylinder bank fuel shutoff, and (iii) pre-scheduled EGR valve control based on the measured accelerator pedal position. In response to detecting the transient tip-in event, an EGR delivery rate is temporarily increased by at least one of (i) the pre-scheduled EGR valve control and (ii) controlling intake/exhaust valves of cylinders of the engine to enable a scavenging mode.

Abstract: Turbocharged engine water vapor ingestion control techniques determine a dew point of a charge air cooler (CAC) in an induction system of the engine based on measured humidity and temperature of a mixture of (i) air drawn into the induction system and (ii) exhaust gas produced by the engine that is cooled and recirculated by a low pressure cooled exhaust gas recirculation (LPCEGR) system of the engine back into the induction system. When the mixture temperature is less than the CAC dew point, a condensate accumulation in the CAC is determined. When the CAC condensate accumulation does not satisfy a set of one or more thresholds, the mixture temperature is increased. When the CAC condensate accumulation satisfies the set of one or more thresholds, an amount of the exhaust gas that is cooled and recirculated by the LPCEGR system is decreased until the mixture temperature meets the CAC dew point.

Abstract: Techniques for controlling a forced-induction engine having a low pressure cooled exhaust gas recirculation (LPCEGR) system comprise determining a target boost device inlet pressure for each of one or more systems that could require a boost device inlet pressure change as part of their operation and boost device inlet pressure hardware limits for a set of components in the induction system, determining a final target boost device inlet pressure based on the determined sets of target boost device inlet pressures and boost device inlet pressure hardware limits, and controlling a differential pressure (dP) valve based on the final target boost device inlet pressure to balance (i) competing boost device inlet pressure targets of the one or more systems and (ii) the set of boost device inlet pressure hardware limits in order to optimize engine performance and prevent component damage.

Abstract: Techniques for setting a boost target for a turbocharged engine comprise (i) operating the engine in a scavenging mode such that opening of intake and exhaust valves of cylinders of the engine overlap and (ii) while transitioning the engine in/out of the scavenging mode: determining an engine torque request, creating a torque reserve by setting independent targets for throttle inlet pressure (TIP) and intake manifold absolute pressure (MAP), determining a target TIP based on a target total air charge, engine speed, and a previously-determined target engine volumetric efficiency (VE), controlling a wastegate valve based on the target TIP, determining a target MAP based on the engine torque request, and controlling a throttle valve based on the target MAP. During steady-state scavenging operation, the controller calculates a conventional target TIP based on the engine torque request and controls the wastegate valve based on the conventionally calculated target TIP.

Abstract: Systems and methods for a turbocharged gasoline engine utilize a controller configured to receive a set of parameters including a measured pressure delta across an exhaust gas recirculation (EGR) valve disposed in a low pressure EGR (LPEGR) system of the engine and a measured pressure at an outlet of a differential pressure (dP) valve disposed in and distinct from a throttle valve of an induction system of the engine. The controller is further configured to determine a set of modeled pressures based on the set of parameters, a target EGR valve mass flow, a target EGR valve delta pressure, a current dP valve mass flow, and a pressure at an outlet of the air filter, determine target positions for the EGR valve and the dP valve based on the set of modeled pressures, and control the EGR valve and the dP valve based on their respective target positions.

Abstract: An engine control system for a vehicle includes an oxygen mass flow rate module, an oxygen per cylinder module, and a fuel control module. The oxygen mass flow rate module generates a mass flow rate of oxygen flowing into an engine based on a mass air flow rate (MAF) into the engine and a percentage of oxygen by volume measured using an intake oxygen (IO) sensor in an intake system. The oxygen per cylinder module generates a mass of oxygen for a combustion event of a cylinder of the engine based on the mass flow rate of oxygen flowing into the engine. The fuel control module controls fueling to the cylinder for the combustion event based on the mass of oxygen.

Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode and a spark-ignition combustion mode employing late intake valve closing. A method for operating the internal combustion engine includes determining an amount of residual gas re-inducted into a combustion chamber from a previous engine cycle and determining an amount of fresh air trapped in the combustion chamber for the present engine cycle based upon the amount of residual gas re-inducted into the combustion chamber from the previous engine cycle. Engine fueling to the cylinder for the present engine cycle is controlled based upon the amount of fresh air trapped in the combustion chamber for the present engine cycle.

Abstract: A control technique for an engine having a two-step variable valve lift system includes a controller receiving a pressure in an intake manifold of the engine from a manifold absolute pressure (MAP) sensor and a position of an EGR valve of the engine from an exhaust gas recirculation (EGR) sensor. In response to the controller detecting an upcoming HL-to-LL valve state transition, a set of airflow actuators of the engine is controlled, based on the intake manifold pressure and the EGR valve position, to generate a first torque reserve. In response to generating the first torque reserve, the controller then commands the HL-to-LL transition and depletion of the first torque reserve during the HL-to-LL transition to mitigate torque disturbance associated with this transition.

Abstract: Techniques for learning endstop position(s) of an actuator for a wastegate valve include detecting a learn condition and, in response to detecting the learn condition, performing a learn procedure for the actuator endstop position(s). The learn procedure includes commanding the actuator to a desired position past the endstop position corresponding to a fully-closed wastegate valve while rate-limiting a velocity of the actuator. When the difference reaches its maximum allowed value and the velocity falls below a fraction of its rate limit, the endstop position is learned. When the wastegate valve is requested open, the actuator is then controlled using the learned endstop position. Reference stiffness for a fully-closed wastegate valve could be obtained, and subsequent stiffness checks could then be periodically performed and, if less than the reference stiffness, a duty cycle of the actuator could be increased during open-loop control.

Abstract: An engine bank-to-bank airflow balancing technique includes calculating current and offset volumetric efficiencies of the engine and calculating a slope representing (i) a difference between the offset and current volumetric efficiencies and (ii) a difference between offset and current intake camshaft positions. Based on the respective exhaust gas oxygen concentrations, the technique involves calculating a volumetric efficiency correction corresponding to each cylinder bank and based on the slope and the volumetric efficiency corrections, calculating target intake camshaft position shifts. The technique further involves controlling offsets of the intake camshafts based on the target intake camshaft position shifts.

Abstract: A technique is provided for compensating an untrimmed oxygen (O2) sensor utilized in operation of an exhaust gas recalculation (EGR) system associated with an engine. The technique includes, in one implementation, receiving a measurement from the O2 sensor at a known pressure, where the O2 sensor is positioned on an intake side of an engine system. Humidity compensation and pressure compensation are then determined for the O2 sensor measurement, where the pressure compensation is based in part on the humidity compensation. The EGR system is controlled using the untrimmed O2 sensor measurement that has been compensated for pressure and humidity.

Abstract: A boost purge ejector tee arrangement is integrated into a turbocompressor associated with an engine and includes first and second passages, an inlet port and a nozzle. The first passage is formed into a housing of the turbocompressor and includes an outlet in communication with a turbocompressor inlet. The second passage is formed into the housing and includes a boost air inlet in communication with an internal outlet area of the turbocompressor and intersecting the first passage. The inlet port is associated with the housing and intersects the first passage. The nozzle is positioned in the first passage such that an outlet of the nozzle is proximate the intersection of the inlet port and first passage. During a boost mode of operation, the second passage is adapted to receive boost air flow, which flows through the nozzle thereby creating a vacuum and drawing purge through the inlet port.

Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode and a spark-ignition combustion mode employing late intake valve closing. A method for operating the internal combustion engine includes determining an amount of residual gas re-inducted into a combustion chamber from a previous engine cycle and determining an amount of fresh air trapped in the combustion chamber for the present engine cycle based upon the amount of residual gas re-inducted into the combustion chamber from the previous engine cycle. Engine fueling to the cylinder for the present engine cycle is controlled based upon the amount of fresh air trapped in the combustion chamber for the present engine cycle.

Abstract: A system for a vehicle includes a mode control module and a valve control module. The mode control module selectively sets an ignition mode for an engine to one of a spark ignition (SI) mode and a homogenous charge compression ignition (HCCI) mode. In response to the ignition mode transitioning from the SI mode to the HCCI mode during a first engine cycle, the valve control module operates an exhaust valve in a high lift mode during a second engine cycle, operates an intake valve in a low lift mode during the second engine cycle, and operates the exhaust and intake valves in the low lift mode during a third engine cycle. The first engine cycle is before the second engine cycle, and the second engine cycle is before the third engine cycle.

Abstract: An engine control system for a vehicle includes an oxygen mass flow rate module, an oxygen per cylinder module, and a fuel control module. The oxygen mass flow rate module generates a mass flow rate of oxygen flowing into an engine based on a mass air flow rate (MAF) into the engine and a percentage of oxygen by volume measured using an intake oxygen (IO) sensor in an intake system. The oxygen per cylinder module generates a mass of oxygen for a combustion event of a cylinder of the engine based on the mass flow rate of oxygen flowing into the engine. The fuel control module controls fueling to the cylinder for the combustion event based on the mass of oxygen.

Abstract: A system for a vehicle includes a mode control module and a valve control module. The mode control module selectively sets an ignition mode for an engine to one of a spark ignition (SI) mode and a homogenous charge compression ignition (HCCI) mode. In response to the ignition mode transitioning from the SI mode to the HCCI mode during a first engine cycle, the valve control module operates an exhaust valve in a high lift mode during a second engine cycle, operates an intake valve in a low lift mode during the second engine cycle, and operates the exhaust and intake valves in the low lift mode during a third engine cycle. The first engine cycle is before the second engine cycle, and the second engine cycle is before the third engine cycle.