Methods and systems are described for conserving energy used by an energy consuming device. In certain embodiments, an energy conservation system can be configured to deliver energy to the energy consuming device for a period, followed by a period where energy delivery is dampened and/or cut. By cycling the delivery of energy in this fashion, the energy conservation can achieve a pulsed efficiency.

A control unit controls a combustion state of an internal combustion engine in accordance with a drive torque requested by a driver. The control unit performs a switching control to switch at least a combustion state between lean-burn combustion and stoichiometric combustion. A monitor unit performs torque monitoring to determine abnormality of a request torque, which is requested to the internal combustion engine, and a generated torque of the internal combustion engine based on the request torque and an estimation torque, which is an estimation value of an actual torque of the internal combustion engine. A combustion state determining unit determines whether the combustion state in the control unit is the lean-burn combustion or the stoichiometric combustion. A computing unit computes the estimation torque in accordance with the combustion state determined by the combustion state determining unit.

Methods and systems are described for conserving energy used by an energy consuming device. In certain embodiments, an energy conservation system can be configured to deliver energy to the energy consuming device for a period, followed by a period where energy delivery is dampened and/or cut. By cycling the delivery of energy in this fashion, the energy conservation can achieve a pulsed efficiency.

Various methods and systems are provided for skip-firing an engine. As one embodiment, a method for an engine includes firing all cylinders of the engine and not altering the closing timing of the intake valves when fueling demands are greater than a threshold. The method further includes skip-firing the engine when fueling demands are less than a threshold, and holding open the intake valves of skipped cylinders for a greater duration than intake valves of firing cylinders.

In a method for reducing particulate emissions of an internal combustion engine during a cold start of the internal combustion engine, the combustion chamber temperature and the ambient temperature are determined. A cold start condition is recognized when the combustion chamber temperature is below a first threshold temperature and the ambient temperature is below a second threshold temperature. In this case, the internal combustion engine is dragged by means of the starter, wherein air that is present in the combustion chambers is compressed and heated. This heat is discharged to the combustion chamber walls, which are likewise heated up. In this operating situation there is no fuel injection in the combustion chambers and no ignition, so that no combustion takes place in the combustion chambers and the internal combustion engine compresses solely fresh air. The combustion chambers heat up due to the compression work, thus achieving better evaporation of the fuel in the combustion chamber. An initially switched-off fuel injection into the combustion chambers is switched on when the combustion chamber walls of the combustion chambers have reached a sufficient temperature, so that the soot formation due to unburned fuel striking the cold combustion chamber walls is reduced.

A control unit controls a combustion state of an internal combustion engine in accordance with a drive torque requested by a driver. The control unit performs a switching control to switch at least a combustion state between lean-burn combustion and stoichiometric combustion. A monitor unit performs torque monitoring to determine abnormality of a request torque, which is requested to the internal combustion engine, and a generated torque of the internal combustion engine based on the request torque and an estimation torque, which is an estimation value of an actual torque of the internal combustion engine. A combustion state determining unit determines whether the combustion state in the control unit is the lean-burn combustion or the stoichiometric combustion. A computing unit computes the estimation torque in accordance with the combustion state determined by the combustion state determining unit.

A control system for an engine includes one or more processors configured to determine when a change in one or more of oxygen or fuel supplied to an engine. The one or more processors also are configured to, responsive to determining the change in oxygen and/or fuel supplied to an engine, direct one or more fuel injectors of the engine to begin injecting fuel into one or more cylinders of the engine during both a first fuel injection and a second fuel injection during each cycle of a multi-stroke engine cycle of the one or more cylinders.

A liquid fuel injector for a fuel system in an internal combustion engine includes two injection control valves for controlling two outlet checks. A common nozzle supply cavity is fluidly connected to an inlet passage and supplies each of the two sets of nozzle outlets opened and closed by the outlet checks. A first nozzle outlet set forms a narrower spray angle and has a first combination of outlet number and outlet size, and a second nozzle outlet set forms a wider spray angle and has a second combination of outlet number and outlet size. The first nozzle outlet set has a greater steady flow than the second nozzle outlet set.

Various methods and systems are provided for skip-firing an engine. As one embodiment, a method for an engine includes firing all cylinders of the engine and not altering the closing timing of the intake valves when fueling demands are greater than a threshold. The method further includes skip-firing the engine when fueling demands are less than a threshold, and holding open the intake valves of skipped cylinders for a greater duration than intake valves of firing cylinders.

In control device of an internal combustion engine, for each first period, a calculation unit calculates number of fuel injections within one combustion cycle and fuel injection rate. For first period, a first storage unit stores number of fuel injections and fuel injection rate of calculation unit. For each second period, a reference unit refers to the number of fuel injections and fuel injection rate stored by the first storage unit. A second storage unit stores for an interval, from the start time of the first fuel injection until start of the last fuel injection of at least one combustion cycle, the number of fuel injections and fuel injection rate referred to by reference unit. A control unit controls a fuel injection valve so that fuel is injected in accordance with the number of fuel injections fuel injection rate stored by second storage unit.