Airflow correction learning using electronic throttle control
View Patent ↗A correction system and method for an electronic throttle control includes a generator module that generates a learned-correction value corresponding to a first air-learn index. The learned-correction value is used to compensate a throttle position. A correction module writes to a throttle position correction array with the learned-correction value when an air-learn value equals a predetermined stability threshold.
1. A correction system for electronic throttle control, comprising:
a generator module that generates a learned-correction value corresponding to a first air-learn index, wherein said learned-correction value is used to compensate a throttle position; and
a correction module that writes to a throttle position correction array with said learned-correction value when an air-learn value equals a predetermined stability threshold.
2. The correction system of claim 1 further comprising:
a throttle position sensor that senses throttle position and an indexing module that generates said first air-learn index based on said throttle position.
3. The correction system of claim 1 wherein said air-learn value is set equal to zero and a second air-learn index is set equal to said first air-learn index when stability conditions are not satisfied.
4. The correction system of claim 1 wherein said correction module increments a volatile histogram at said first air-learn index when said learned-correction value is stored at said first air-learn index of said throttle position correction array.
5. The correction system of claim 1 wherein said correction module increments said air-learn value when stability conditions are satisfied and updates an air-learn threshold to equal said first air-learn index when said air-learn value equals said predetermined stability threshold.
6. The correction system of claim 5 wherein said stability conditions include at least one of: said air-learn index does not exceed said air-learn threshold, said first air-learn index is equal to a second air-learn index, and said air-learn index is greater than zero.
7. The correction system of claim 4 further comprising:
a shutdown module that updates a non-volatile histogram indexed by air lean indexes based on said volatile histogram.
8. The correction system of claim 7 wherein said shutdown module updates said non-volatile histogram when at least one cell in said volatile histogram exceeds zero.
9. The correction system of claim 8 further comprising:
an initialization module that clears said air-learn value, that sets a second air-learn index equal to zero, and that determines said air-learn threshold when at least one of: power-up, running reset, and other reset has occurred.
10. The correction system of claim 9 wherein said initialization module sets said air-learn threshold equal to a cell of said non-volatile histogram, wherein said cell contains a value that is greater than zero.
11. A method for controlling an electronic throttle system comprising:
generating a learned-correction value corresponding to a first air-learn index, wherein said learned-correction value is used to compensate a throttle position; and
updating said throttle position correction array with said learned-correction value when said air-learn value equals a predetermined stability threshold.
12. The method of claim 11 further comprising sensing throttle position and generating said first air-learn index based on said throttle position.
13. The method of claim 11 wherein said air-learn value is set equal to zero and a second air-learn index is set equal to said first air-learn index when said stability conditions are not satisfied.
14. The method of claim 11 further comprising:
incrementing a volatile histogram at said first air-learn index when said learned-correction value is stored at said first air-learn index of said throttle position correction array.
15. The method of claim 11 wherein said correction module increments an air-learn value when said stability conditions are satisfied and updates an air-learn threshold to equal said first air-lean index when said air-learn value equals said predetermined stability threshold.
16. The method of claim 15 wherein said stability conditions include at least one of: said air-learn index does not exceed said air-learn threshold, said first air-learn index is equal to a second air-learn index, and said air-learn index is greater than zero.
17. The method of claim 14 further comprising:
updating a non-volatile histogram indexed by air lean indexes based on said volatile histogram.
18. The method of claim 17 wherein said non-volatile histogram is updated when at least one cell in said volatile histogram exceeds zero.
19. The method of claim 17 wherein said air-learn value is cleared, a second air-learn index is set equal to zero, and said air-learn threshold is determined when at least one of: power-ups, running resets, and other resets has occurred.
20. The method of claim 19 , wherein said air-learn threshold is set equal to a cell of said non-volatile histogram, wherein said cell contains a value that is greater than zero.