Systems and methods for generating auxiliary torque are provided. In one example, a method for controlling a supercharger comprises, responsive to requested torque exceeding spark authority of an engine, varying a current applied to a motor of the supercharger to provide an amount of torque to a crankshaft of the engine. In this way, a supercharger can be controlled to compensate for an engine torque shortfall.

In a method for operating an internal combustion engine of a motor vehicle having an automatic transmission, a torque generated by the internal combustion engine is reduced as a function of an operating state of a drive train of the motor vehicle. As a function of an excess of combustion air occurring when the torque is reduced and supplied to the internal combustion engine by an exhaust gas turbocharger, fuel combustion efficiency in at least one combustion chamber of the internal combustion engine, which is related to the torque generated by the combustion chamber, is reduced. The combustion efficiency is reduced by at least one late post-injection of fuel into the at least one combustion chamber of the internal combustion engine.

Vehicle designers are largely walking away from internal-combustion engines to battery and electric motors. Until infrastructure is developed to support total electrification, hybrid-electric vehicles (HEVs) which include both an internal combustion engine and an electric machine are a step toward electrification and higher system fuel efficiency while retaining the expected vehicle range. To obtain even higher system fuel efficiency combustion modes that provide higher efficiency than spark-ignition (SI) operation can be used in HEVs. A problem with such combustion modes is that they cannot be used over as wide an operating range as SI operation and transitions among modes is slow and cumbersome. By having the ICE installed into a HEV be a multi-combustion mode engine and having the EM to coordinate mode switches to be smooth, the high fuel-efficiency of alternative combustion modes can be exploited while providing smooth operation expected by vehicle users.

A control method for an internal combustion engine configured to implement fuel cut in response to becoming zero of an accelerator opening degree during travel of a vehicle, and generate an antiphase torque after the fuel cut by supplying fuel to a cylinder, in order to cancel out vibration of the vehicle caused due to the fuel cut includes setting a timing of generating the antiphase torque to be later than that for normal operation, in response to implementation of the fuel cut under high torque idle operation in which a torque of the internal combustion engine immediately before the fuel cut where the accelerator opening degree is zero is higher than that in the normal operation.

Engine controllers and control schemes are provided for managing engine state transitions requiring increased compressor pressure ratios in turbocharged engines. In some circumstances, turbo lag can be mitigated by initially transitioning the engine to an intermediate engine state that directly or indirectly increases airflow through the engine and turbocharger relative to what would be possible if the engine were immediately commanded to operate at the target engine state. After reaching a point where the desired torque is actually generated at the intermediate engine state, the operational settings are gradually reduced to the target effective firing density while increasing the operational compressor pressure ratio to the target compressor ratio.

A skip fire control system for an engine of a vehicle includes a set of sensors configured to measure a set of operating parameters of the engine corresponding to a volumetric efficiency of the engine, a set of sub-systems having a set of operational states that affect transitions between different firing patterns/fractions of the engine, and a controller configured to, based on the set of operating parameters and the set of operational states of the set of sub-systems, determine a best firing pattern/fraction by taking into account losses or penalties to transition at least some of the set of operational states of the set of sub-systems to obtain a target firing pattern/fraction, and control the engine based on the target firing pattern/fraction to maximize an efficiency of the engine.

A system and method for transitioning a firing fraction of a variable displacement internal combustion engine when generating a desired torque output. During and following the transition to the second firing fraction, a combustion recipe is ascertained and used operating the cylinders of the variable displacement internal combustion engine to generate the desired torque output. The recipe is preferably optimized for the engine operating at the second firing fraction, at least relative to the previous charge of the previous combustion recipe used with the first firing fraction.

Methods and systems are provided for controlling a vehicle engine to deliver desired torque to a power take off device coupled to the engine. In one example, the method may include, learning a filtered PTO torque demand during vehicle acceleration, and steady state operation, and during transition in engine states using the learned PTO torque demand to adjust engine speed in order to deliver a desired engine torque output for optimal operation of the PTO device.

With a torque-controlled internal combustion engine and a variable-speed transmission having fixed shift gear ratios, during a shift, the internal combustion engine is controlled in such manner that the drive output torque of the transmission remains the same before and after the shift.

A variety of methods and arrangements are described for controlling transitions between firing fractions during skip fire and potentially variable displacement operation of an engine. In general, cam first transition strategies are described in which the cam phase is changed to, or close to a target cam phase before a corresponding firing fraction change is implemented. When the cam phase change associated with a desired firing fraction change is relatively large, the firing fraction change is divided into a series of two or more firing fraction change steps—with each step using a cam first transition approach. A number of intermediate target selection schemes are described as well.