Internal combustion engine control for improved fuel efficiency
First Claim
1. An internal combustion engine comprising:
- a plurality of working chambers each arranged to operate in a succession of working cycles;
a fuel delivery system arranged to facilitate the delivery of fuel into the working chambers; and
a fuel delivery control unit that enables the engine to operate in a variable displacement mode in which the fuel delivery system is controlled to selectively deliver fuel to the working chambers during a first selected group of fired working cycles and to skip delivery of fuel to the working chambers during a second selected group of skipped working cycles,wherein the fuel delivery control unit includes a predictive adaptive controller and is arranged to dynamically determine the fired and skipped working cycles on a working cycle by working cycle basis during operation of the engine based at least in part upon a feedback signal indicative of at least one of requested and actual working cycle firings in order to deliver a desired engine output, andwherein the amount of fuel selectively delivered to the working chambers during each of the first selected group of fired working cycles is substantially optimized for the amount of air delivered to the working chambers during the first set of the active working cycles.
1 Assignment
0 Petitions
Accused Products
Abstract
A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, selected combustion events are skipped during operation of the internal combustion engine so that other working cycles can operate at a better thermodynamic efficiency. In one aspect of the invention, an engine is controlled to operate in a variable displacement mode. In the variable displacement mode, fuel is not delivered to the working chambers (e.g. cylinders) during selected “skipped” working cycles. During active (“non-skipped”) working cycles, a maximum (e.g., unthrottled) amount of air and an optimized amount of fuel is delivered to the relevant working chambers so that the fired working chambers can operate at efficiencies closer to their optimal efficiency. A controller is used to dynamically determine the chamber firings required to provide the engine torque based on the engine'"'"'s current operational state and conditions. The chamber firings may be sequenced in real time or in near real time in a manner that helps reduce undesirable vibrations of the engine.
238 Citations
16 Claims
-
1. An internal combustion engine comprising:
-
a plurality of working chambers each arranged to operate in a succession of working cycles; a fuel delivery system arranged to facilitate the delivery of fuel into the working chambers; and a fuel delivery control unit that enables the engine to operate in a variable displacement mode in which the fuel delivery system is controlled to selectively deliver fuel to the working chambers during a first selected group of fired working cycles and to skip delivery of fuel to the working chambers during a second selected group of skipped working cycles, wherein the fuel delivery control unit includes a predictive adaptive controller and is arranged to dynamically determine the fired and skipped working cycles on a working cycle by working cycle basis during operation of the engine based at least in part upon a feedback signal indicative of at least one of requested and actual working cycle firings in order to deliver a desired engine output, and wherein the amount of fuel selectively delivered to the working chambers during each of the first selected group of fired working cycles is substantially optimized for the amount of air delivered to the working chambers during the first set of the active working cycles. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. An internal combustion engine comprising:
-
a plurality of working chambers each arranged to operate in a succession of working cycles; a fuel delivery system arranged to facilitate the delivery of fuel into the working chambers; and a fuel delivery control unit that includes a sigma delta control circuit, a synchronizer, and a sequencer, the fuel delivery control unit enabling a variable displacement mode in which the fuel injection system is controlled to selectively deliver fuel to the working chambers during a first selected set of active working cycles and to skip delivery of fuel to the working chambers during a second selected set of passive working cycles, wherein, the sigma delta control circuit receives an analog input signal indicative of a desired engine output and outputs a feedback modified digital signal representation of the analog input signal, the synchronizer receives the digital signal representation of the analog signal, and outputs a drive pulse signal that is synchronized with the engine speed, wherein the drive pulse signal generally indicates when active working cycles are appropriate to deliver the desired engine output, the sequencer receives the drive pulse signal and determines the first and second sets of working cycles on a working cycle by working cycle basis based at least in part on the received drive pulse signal, and the air delivered to the working chambers during the first set of active working cycles is unthrottled or at a fixed throttle position. - View Dependent Claims (11)
-
-
12. A method of controlling the operation of an internal combustion engine having a plurality of working chambers, each working chamber being generally arranged to operate in a succession of working cycles, the method comprising operating the engine in a variable displacement mode that includes:
-
delivering air to the working chambers during the active working cycles, wherein the air delivered to the working chambers is either unthrottled or delivered at a first set air throttle position; delivering fuel to the working chambers in a fuel delivery pattern dynamically determined on a working cycle by working cycle basis during operation of the engine that skips delivery of fuel during selected skipped working cycles and delivers fuel during selected active working cycles; wherein an amount of fuel delivered to the working chambers during a first set of the active working cycles is substantially optimized for the amount of air delivered to the working chambers during the first set of the active working cycles; and wherein the fuel delivery pattern is determined at least in part using predictive adaptive control to provide a desired engine output, and wherein the predictive adaptive control includes feedback indicative of at least one of requested and actual working cycle firings. - View Dependent Claims (13, 14, 15, 16)
-
Specification