Abstract: A variety of skip fire engine controllers and control techniques are described. In some preferred embodiments, a skip fire engine controller is provided that includes a firing fraction calculator, an engine settings controller, a firing fraction adjuster and a firing controller. The firing fraction calculator determines a reference firing fraction indicative of a firing fraction suitable for delivering a desired engine output at a reference working chamber firing output. The engine settings controller is arranged to set selected engine settings. The firing fraction adjuster determines an adjusted firing fraction that scales the reference firing fraction appropriately such that the engine will deliver the desired engine output at the current engine settings even when the actual working chamber firing outputs do not equal the reference working chamber firing output. The firing controller direct workings chamber firings in a skip fire manner that delivers the adjusted firing fraction.

Abstract: In various described embodiments skip fire control is used to deliver a desired engine output. A controller determines a skip fire firing fraction and (as appropriate) associated engine settings that are suitable for delivering a requested output. In one aspect, the skip fire controller is arranged to select a base firing fraction that has a repeating firing cycle length that will repeat at least a designated number of times per second at the current engine speed. Such an arrangement can be helpful in reducing the occurrence of undesirable vibrations.

Abstract: Methods and arrangements for controlling hybrid powertrains are described. In one aspect, an engine is alternatingly operated at different effective displacements. One displacement delivers less than a requested powertrain output and the other delivers more. A motor/generator system is used to add and subtract torque to/from the powertrain to cause the net delivery of the requested powertrain output. In some embodiments, energy added and subtracted from the powertrain is primarily drawn from and stored in a capacitor (e.g., a supercapacitor or an ultracapacitor) when alternating between effective displacements. In another aspect a hybrid powertrain arrangement includes an engine a motor/generator and an energy storage system that includes both a battery and a capacitor. The capacitor stores and delivers electrical energy to the motor/generator unit during operation of the engine in a variable displacement or skip fire mode.

Abstract: In various described embodiments skip fire control is used to deliver a desired engine output. A controller determines a skip fire firing fraction and (as appropriate) associated engine settings that are suitable for delivering a requested output. In one aspect, the firing fraction is selected from a set of available firing fractions, with the set of available firing fractions varying as a function of engine speed such that more firing fractions are available at higher engine speeds than at lower engine speeds. The controller then direct firings in a skip fire manner that delivers the selected fraction of firings.

Abstract: A variety of methods and arrangements for operating an internal combustion engine and one or more motor/generators in a hybrid vehicle are described. Generally, the engine is operated in a variable displacement or skip fire mode. Depending on the state of charge of an energy storage device and/or other factors, the engine is operated to generate more or less than a desired level of torque. The one or more motor/generators are used to add or subtract torque so that the motor/generator(s) and the engine collectively deliver the desired level of torque. In some embodiments, the engine may be run with a substantially open throttle to reduce pumping losses and improve fuel efficiency.

Abstract: A variety of methods and arrangements for operating an internal combustion engine and one or more motor/generators in a hybrid vehicle are described. In various embodiments, the engine is operated in a skip fire mode. Depending on the state of charge of an energy storage device and/or other factors, the engine is operated to generate more or less than a desired level of torque. The one or more motor/generators are used to add or subtract torque so that the motor/generator(s) and the engine collectively deliver the desired level of torque. In some embodiments, the engine may be run with a substantially open throttle to reduce pumping losses and improve fuel efficiency.