Abstract: A control system and method for operating an engine includes a threshold determination module that determines a plurality of combustion mode thresholds based on the engine speed and engine temperature. The control module also includes a transition module that compares the engine load and the plurality of combustion mode thresholds and changes a combustion mode of the engine in response to comparing the engine load and the plurality of combustion mode thresholds.

Abstract: A method for controlling combustion in a spark-ignition direct-injection internal combustion engine includes monitoring an engine operating mode and an ambient parameter, determining a deviation of the ambient parameter relative to a nominal ambient parameter, determining a nominal desired engine operation parameter based on engine speed and load, determining and adjusted desired engine operation parameter based on the nominal desired engine operation parameter and said deviation of the ambient parameter, and controlling the engine based on the engine operating mode and one of the nominal desired engine operation parameter and adjusted desired engine operation parameter.

Abstract: A method for operating an internal combustion engine includes determining an actual combustion heat release during ongoing engine operation, calculating an expected combustion heat release corresponding to engine operation associated with the actual combustion heat release during ongoing engine operation, determining a difference between the actual combustion heat release and the expected combustion heat release, and operating the internal combustion engine in a homogeneous-charge compression-ignition combustion mode to achieve a preferred combustion phasing during each combustion cycle in response to the difference between the actual combustion heat release and the expected combustion heat release.

Abstract: A method for controlling a multi-cylinder direct-injection internal combustion engine includes establishing an external exhaust gas recirculation valve from a present position to a target position to achieve a target exhaust gas recirculation, and synchronizing combustion initiation timing with actual exhaust gas recirculation as actual exhaust gas recirculation changes from a first exhaust gas recirculation value corresponding to the present position of the external exhaust gas recirculation valve to a second exhaust gas recirculation value corresponding to the target position of the external exhaust gas recirculation valve.

Abstract: A direct-injection internal combustion engine is fluidly coupled to a passive SCR system including a three-way catalytic converter upstream to an ammonia-selective catalytic reduction catalyst. Transition from an HCCI combustion mode to an SI combustion mode includes determining a preferred air/fuel ratio to achieve a minimum fuel consumption and maintain combustion stability at an acceptable level for a predetermined engine operating point during the SI combustion mode. A fuel injection timing, an engine spark timing and an engine valve lift are substantially immediately controlled from respective HCCI combustion mode settings to respective SI combustion mode settings. A transition to the preferred air/fuel ratio is coordinated with a transition of an engine valve phase from a respective HCCI combustion mode setting to a respective SI combustion mode phase setting.

Abstract: A method to control a non-linear system includes operating a learning cycle to approximate characteristics of the system and, once the learning cycle is complete, operating the system based upon the characteristics. The learning cycle includes monitoring operation of the system, approximating the characteristics of the system with a recursive least squares approximation based upon the monitored operation, comparing variance of the operation to a threshold variance, and completing the learning cycle based upon the variance exceeding the threshold variance.

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: A method for controlling combustion in a multi-cylinder spark-ignition direct-injection internal combustion engine includes determining a desired combustion phasing for maintaining acceptable combustion properties, monitoring combustion phasing of each cylinder, selecting a target combustion phasing corresponding to one of the cylinders having a most retarded combustion phasing, adjusting spark timing in each cylinder not having the most retarded combustion phasing to achieve the target combustion phasing to balance the combustion phasing in all the cylinders at the target combustion phasing, and adjusting an external EGR percentage to converge the balanced combustion phasing in all the cylinders toward the desired combustion phasing.

Abstract: A control system for an engine includes a feedback determination module, a feed-forward determination module, and a valve control module. The feedback determination module generates an exhaust gas recirculation (EGR) feedback value based on engine speed and a difference between desired and measured combustion phasing. The feed-forward determination module generates an EGR feed-forward value based on a difference between desired and measured mass air flow (MAF) rates. The valve control module controls an EGR valve based on the EGR feedback and feed-forward values, an intake manifold absolute pressure (MAP), an engine speed, and an exhaust back pressure (EBP).

Abstract: A multi-cylinder spark-ignition direct-injection internal combustion engine is re-fired subsequent to a fuel cutoff event wherein fuel to all cylinders is cutoff. Re-firing the engine includes selectively firing individual cylinders during re-firing engine cycles exclusively at a predetermined fixed fuel mass until all cylinders have been fired at least once, whereafter subsequent firing of individual cylinders is not limited to the predetermined fixed fuel mass.

Abstract: A control system for a homogeneous charge compression ignition (HCCI) engine includes a timing adjustment module and a combustion control module. The timing adjustment module, per combustion event, advances timings of N fuel injections and retards timings of M fuel injections and spark during a transition from HCCI combustion to mixed-mode combustion. The combustion control module subsequently retards the timings of the N fuel injections and advances the timings of the M fuel injections and the spark to desired timings, respectively, wherein the N fuel injections and the M fuel injections occur sequentially during each combustion event of the HCCI engine, and wherein N and M are integers greater than or equal to zero.

Abstract: An internal combustion engine operates in a homogeneous-charge compression-ignition combustion mode. A method for controlling the internal combustion engine in response to a fast transient event from a low-load state to a high-load state includes operating the engine with a negative valve overlap between an intake valve and an exhaust valve, and determining a preferred combustion phasing responsive to the high-load state. A preferred EGR mass and a preferred intake valve timing corresponding to the preferred combustion phasing are determined A first intake valve timing is determined in response to a difference between the preferred EGR mass and an actual EGR mass. The intake valve timing is controlled in response to a difference between the preferred intake valve timing and the first intake valve timing.

Abstract: A method for controlling combustion in a spark-ignition direct-injection internal combustion engine includes monitoring an engine operating mode and an ambient parameter, determining a deviation of the ambient parameter relative to a nominal ambient parameter, determining a nominal desired engine operation parameter based on engine speed and load, determining and adjusted desired engine operation parameter based on the nominal desired engine operation parameter and said deviation of the ambient parameter, and controlling the engine based on the engine operating mode and one of the nominal desired engine operation parameter and adjusted desired engine operation parameter.

Abstract: A method to control an internal combustion engine includes controlling the engine in a homogeneous charge compression ignition mode and depending upon the operating range of the engine operating both intake and exhaust valves with one of a high-lift profile or a low lift profile or the exhaust valves with a low-lift profile and the intake valves with a high-lift profile.

Abstract: A method for operating a direct-injection internal combustion engine includes unevenly distributing load among a plurality of cylinders by operating a portion of the plurality of cylinders in a spark ignition mode and the remaining portion of the plurality of cylinders in a homogeneous charge compression ignition mode.

Abstract: A method for operating a multi-cylinder spark-ignition direct-injection internal combustion engine responsive to a low load demand includes monitoring an engine state associated with combustion for each cylinder during each combustion cycle during low load operation, determining a combustion stability index for each cylinder based upon the monitored engine state associated with combustion for the respective cylinder, and individually adjusting an initiation of a spark discharge relative to an end of a fuel injection event for each cylinder based upon the combustion stability index determined for the respective cylinder.

Abstract: Controlling combustion in a spark-ignition direction-injection internal combustion engine includes providing an initial injected fuel mass timing and an initial spark ignition timing. A combustion phasing error is monitored and compared with each of the initial injected fuel mass timing and the initial spark ignition timing. An adjusted injected fuel mass timing and an adjusted desired spark ignition timing is determined based on the comparing for maintaining a desired combustion phasing.

Abstract: A method for controlling an internal combustion engine includes monitoring an engine operating state and selectively operating the engine in a multiple-injection, multiple-ignition combustion mode comprising three injection events based upon the engine operating state. The selective operation includes controlling a first injection during a recompression period of the combustion cycle, controlling a second injection event effective to establish a homogeneous fuel charge prior to a main combustion, and controlling a third injection late in the compression phase of the combustion cycle.

Abstract: Transitioning between combustion modes includes an intermediate combustion mode. Transitions are controlled in accordance with a preferred fuel mass and permissible fuel mass ranges corresponding to changing intake airflow.

Abstract: A direct injection engine includes a fuel injector receiving a flow of pressurized fuel. The fuel injector provides fuel injections directly into a combustion chamber of the engine. The fuel injector includes a first fuel injector nozzle opening directing with a first narrow injection angle a first portion of a fuel injection mass at a spark gap of a spark plug. The fuel injector further includes a second fuel injector nozzle opening dispersing with a second wider injection angle a second portion of the fuel injection mass within the combustion chamber.