摘要:
Disclosed is an engine control system which is designed to allow homogeneous-charge compression ignition combustion to be performed in an HCCI region (R) defined as an engine operating region including at least a partial-load range of an engine. In a low load zone (R1) of the HCCI region (R), a lift amount of an intake valve (11) is set to a first predetermined value, and an exhaust valve (12) is allowed to start being opened during an intake stroke at a given timing later than an opening timing of the intake valve (11). Further, in the medium load zone of the HCCI region, the lift amount of the intake valve (11) is gradually increased up to a second predetermined value greater than the first predetermined value, along with an increase in an engine load. The engine control system is capable of adequately controlling an amount of burned gas to be introduced into a cylinder, depending on the engine load to allow the HCCI combustion to be adequately performed in a wider engine load range.
摘要:
An internal combustion engine is selectably operable in one of homogeneous charge compression ignition (HCCI) mode with low lift intake and exhaust valve profiles and spark ignition (SI) mode with high lift intake and exhaust valve profiles. Transition from a current combustion mode to a desired combustion mode includes phase adjusting the one of the intake and exhaust valves exhibiting a greater effect upon an effective cylinder volume for a given phase adjustment in the desired combustion mode based upon a desired phasing for the desired combustion mode prior to lift adjusting the one of the intake and exhaust valves and adjusting the other of the intake and exhaust valves.
摘要:
A method of controlling an oil pump of an engine with a variable valve lift apparatus includes: detecting the operation status of a vehicle; determining whether mode change conditions of a variable valve lift apparatus are satisfied; determining whether the mode change condition of the variable valve lift apparatus is a condition for changing from a low lift to a high lift; comparing whether the current oil hydraulic pressure is larger than the current necessary hydraulic pressure, when the mode change condition of the variable valve lift apparatus is a condition for changing from a low lift to a high lift; and increasing oil pressure by controlling the oil pump, when the current oil hydraulic pressure is not larger than the current necessary hydraulic pressure.
摘要:
Methods and systems are provided for a boosted engine having a split intake system coupled to a split exhaust system. Aircharges of differing composition, pressure, and temperature may be delivered to the engine through the split intake system at different points of an engine cycle. In this way, boost and EGR benefits may be extended.
摘要:
Methods and systems are provided for controlling a vehicle system including an engine that is selectively deactivated during engine idle-stop conditions and selectively reactivated during engine restart conditions. One example method comprises, during an engine restart from an idle stop, performing a first combustion event in a cylinder with a piston at an engine crankshaft position that is after a crankshaft position at which said cylinder's exhaust valve opens, and before a crankshaft position at which the cylinder's intake valve closes, during a cycle of said cylinder. In this way, inaccuracies in cylinder aircharge estimation may be reduced, thereby also reducing air-fuel ratio errors and improving the quality and repeatability of engine restarts.
摘要:
Various systems and method for controlling exhaust gas recirculation (EGR) in an internal combustion engine are provided. In one embodiment, a method includes injecting fuel to a subset of cylinders that includes less than all cylinders of a first cylinder group to obtain a target EGR rate. The first cylinder group provides exhaust gas through an exhaust gas recirculation (EGR) passage structure fluidly coupled between the first cylinder group and an intake passage structure. The method further includes injecting fuel to at least one cylinder of a second cylinder group. The second cylinder group provides substantially no exhaust gas through the EGR passage structure.
摘要:
Methods and systems are provided for a boosted engine having a split intake system coupled to a split exhaust system. Aircharges of differing composition, pressure, and temperature may be delivered to the engine through the split intake system at different points of an engine cycle. In this way, boost and EGR benefits may be extended.
摘要:
A method of operating an internal combustion engine includes moving an exhaust valve to a first open position to enable an exhaust product to flow through an exhaust port of the internal combustion engine. The method also includes maintaining the exhaust valve at the first open position for a predetermined time period. The method also includes moving an intake valve to a second open position during the predetermined time period to enable an intake product to flow through an intake port of the internal combustion engine. Additionally, the method includes preventing at least a portion of the intake product from flowing through the exhaust port during the predetermined time period with a first blocking member and a second blocking member.
摘要:
A method for operating an internal combustion engine with compression ignition or with spark ignition as a function of an operating point. A specific residual exhaust-gas quantity in the combustion space is set for compression ignition. The internal combustion engine is operated as a function of the operating point by an outlet cam, by which a first outlet opening phase and a second outlet opening phase take place. The second outlet opening phase commences during an inlet opening phase. At a first operating point in a compression-ignition mode, a residual exhaust-gas quantity in a combustion space is dimensioned as a function of a valve interference set between the inlet and the outlet valve during a charge exchange. At a second operating point in the compression-ignition mode the residual exhaust-gas quantity in the combustion space is dimensioned as a function of a duration of the second outlet opening phase.
摘要:
An engine control system includes a desired manifold absolute pressure (MAP) module, a MAP to torque module, a threshold determination module, and a fuel economy (FE) mode module. The desired MAP module determines a desired MAP for operation of an engine in one of a cylinder deactivation mode and a low-lift mode based on a difference between a desired vacuum and an air pressure upstream of a throttle valve. The MAP to torque module determines a desired torque output of the engine for operation in the one of the cylinder deactivation mode and the low-lift mode based on the desired MAP. The threshold determination module determines an entry torque based on the desired torque output. The FE mode module selectively triggers operation in the one of the cylinder deactivation mode and the low-lift mode based on a comparison of the entry torque and a torque request.