Systems and methods for controlling cylinder deactivation periods and patterns
View Patent ↗Based on a desired average number of activated cylinders per sub-period of a predetermined period including P sub-periods, a cylinder control module selects one of N predetermined cylinder activation/deactivation patterns. The selected cylinder activation/deactivation pattern corresponds to Q activated cylinders per sub-period, Q is an integer between zero and a total number of cylinders of an engine, inclusive, P is an integer greater than one, and the desired average number of active cylinders is a number between zero and the total number of cylinders of the engine. The cylinder control module also determines an adjusted cylinder activation/deactivation pattern based on the selected predetermined cylinder activation/deactivation pattern, generates a desired cylinder activation/deactivation pattern for the predetermined period using the selected predetermined cylinder activation/deactivation pattern during a first number of the P sub-periods and using the adjusted cylinder activation/deactivation pattern during a second number of the P sub-periods.
1. A cylinder control system comprising:
a cylinder control module that:
based on a desired average number of activated cylinders per sub-period of a predetermined period in the future including P sub-periods, selects one of N predetermined cylinder activation/deactivation patterns, the N predetermined cylinder activation/deactivation sequences each including M indicators for the next M cylinders, respectively, in a predetermined firing order of cylinders of an engine, and the M indicators each indicating whether to activate or deactivate the respective one of the M cylinders in the predetermined firing order,
wherein M is an integer greater than a total number of cylinders of the engine, and
wherein the one of the N predetermined cylinder activation/deactivation patterns corresponds to Q activated cylinders per sub-period, Q is an integer between zero and the total number of cylinders of the engine, inclusive, P is an integer greater than one, and the desired average number of active cylinders is a non-integer between zero and the total number of cylinders of the engine;
determines an adjusted cylinder activation/deactivation pattern based on the one of the N predetermined cylinder activation/deactivation patterns;
generates a desired cylinder activation/deactivation pattern for the predetermined period in the future using: (i) the one of the N predetermined cylinder activation/deactivation patterns during a first number of the P sub-periods and (ii) the adjusted cylinder activation/deactivation pattern during a second number of the P sub-periods;
during the predetermined period, activates opening of intake and exhaust valves of first ones of the cylinders that are to be activated based on the desired cylinder activation/deactivation pattern; and
during the predetermined period, deactivates opening of intake and exhaust valves of second ones of the cylinders that are to be deactivated based on the desired cylinder activation/deactivation pattern; and
a fuel control module that provides fuel to the first ones of the cylinders during the predetermined period and that disables fueling to the second ones of the cylinders during the predetermined period.
2. The cylinder control system of claim 1 wherein the cylinder control module changes one deactivated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to an activated cylinder to determine the adjusted cylinder activation/deactivation pattern.
3. The cylinder control system of claim 2 wherein the cylinder control module changes one deactivated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to an activated cylinder when Q is less than the desired average number.
4. The cylinder control system of claim 1 wherein the cylinder control module changes one activated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to a deactivated cylinder to determine the adjusted cylinder activation/deactivation pattern.
5. The cylinder control system of claim 4 wherein the cylinder control module changes one activated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to a deactivated cylinder when Q is greater than the desired average number.
6. The cylinder control system of claim 1 wherein the cylinder control module selects the one of the N predetermined cylinder activation/deactivation patterns based on Q being a nearest integer to the desired average number that is greater than the desired average number.
7. The cylinder control system of claim 1 wherein the cylinder control module selects the one of the N predetermined cylinder activation/deactivation patterns based on Q being a nearest integer to the desired average number that is less than the desired average number.
8. The cylinder control system of claim 1 wherein the cylinder control module further:
determines a second adjusted cylinder activation/deactivation pattern based on the one of the N predetermined cylinder activation/deactivation patterns, wherein the second adjusted cylinder activation/deactivation pattern is different than the adjusted cylinder activation/deactivation pattern; and
generates the desired cylinder activation/deactivation pattern for the predetermined period in the future further using the second adjusted cylinder activation/deactivation pattern during a third number of the P sub-periods.
9. A cylinder control method comprising:
based on a desired average number of activated cylinders per sub-period of a predetermined period in the future including P sub-periods, selecting one of N predetermined cylinder activation/deactivation patterns, the N predetermined cylinder activation/deactivation sequences each including M indicators for the next M cylinders, respectively, in a predetermined firing order of cylinders of an engine, and the M indicators each indicating whether to activate or deactivate the respective one of the M cylinders in the predetermined firing order,
wherein M is an integer greater than a total number of cylinders of the engine, and
wherein the one of the N predetermined cylinder activation/deactivation patterns corresponds to Q activated cylinders per sub-period, Q is an integer between zero and the total number of cylinders of the engine, inclusive, P is an integer greater than one, and the desired average number of active cylinders is a non-integer between zero and the total number of cylinders of the engine;
determining an adjusted cylinder activation/deactivation pattern based on the one of the N predetermined cylinder activation/deactivation patterns;
generating a desired cylinder activation/deactivation pattern for the predetermined period in the future using: (i) the one of the N predetermined cylinder activation/deactivation patterns during a first number of the P sub-periods and (ii) the adjusted cylinder activation/deactivation pattern during a second number of the P sub-periods;
during the predetermined period, activating opening of intake and exhaust valves of first ones of the cylinders that are to be activated based on the desired cylinder activation/deactivation pattern;
during the predetermined period, deactivating opening of intake and exhaust valves of second ones of the cylinders that are to be deactivated based on the desired cylinder activation/deactivation pattern;
during the predetermined period, providing fuel to the first ones of the cylinders; and
during the predetermined period, disabling fueling to the second ones of the cylinders.
10. The cylinder control method of claim 9 wherein the determining the adjusted cylinder activation/deactivation pattern includes changing one deactivated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to an activated cylinder.
11. The cylinder control method of claim 10 wherein the determining the adjusted cylinder activation/deactivation pattern includes changing one deactivated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to an activated cylinder when Q is less than the desired average number.
12. The cylinder control method of claim 9 wherein the determining the adjusted cylinder activation/deactivation pattern includes changing one activated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to a deactivated cylinder.
13. The cylinder control method of claim 12 wherein the determining the adjusted cylinder activation/deactivation pattern includes changing one activated cylinder of the one of the N predetermined cylinder activation/deactivation patterns to a deactivated cylinder when Q is greater than the desired average number.
14. The cylinder control method of claim 9 further comprising selecting the one of the N predetermined cylinder activation/deactivation patterns based on Q being a nearest integer to the desired average number that is greater than the desired average number.
15. The cylinder control method of claim 9 further comprising selecting the one of the N predetermined cylinder activation/deactivation patterns based on Q being a nearest integer to the desired average number that is less than the desired average number.
16. The cylinder control method of claim 9 further comprising:
determining a second adjusted cylinder activation/deactivation pattern based on the one of the N predetermined cylinder activation/deactivation patterns, wherein the second adjusted cylinder activation/deactivation pattern is different than the adjusted cylinder activation/deactivation pattern; and
generating the desired cylinder activation/deactivation pattern for the predetermined period in the future further using the second adjusted cylinder activation/deactivation pattern during a third number of the P sub-periods.