Driveline shift quality in variable valve engine equipped drivelines
In one example, a method for controlling powertrain operation in a vehicle is provided, the powertrain having an engine and an automatic transmission, the engine having at least an electrically actuated cylinder valve. The method includes changing gears from a first discreet gear ratio to a second discreet gear ratio of the transmission; and increasing engine torque during a torque phase of said gear change by changing operation of the electrically actuated cylinder valve, and decreasing engine torque during an inertia phase of said gear change.
1. A method for controlling powertrain operation in a vehicle, the powertrain having an engine and an automatic transmission, the engine having at least an electrically actuated cylinder valve, the method comprising:
changing gears from a first discrete gear ratio to a second discrete gear ratio of the transmission; and
increasing engine torque during a torque phase of said gear change by changing operation of the electrically actuated cylinder valve, and decreasing engine torque during an inertia phase of said gear change,
wherein said increasing engine torque during said torque phase of said gear change includes coordinated adjusting of valve timing of an electrically actuated intake valve and moving of a throttle plate,
wherein said coordinated adjusting involves first reducing intake valve opening timing to reduce engine torque until reaching a minimum valve opening amount, and then further reducing a number of cylinders carrying out combustion along with adjustment of the throttle.
2. The method of claim 1 wherein said torque is decreased by retarding spark timing.
3. The method of claim 1 wherein said torque is decreased by changing intake valve timing of the electrically actuated cylinder intake valve.
4. The method of claim 1 wherein said torque is decreased by closing a throttle valve.
5. The method of claim 1 wherein said torque is decreased by reducing a number of cylinders carrying out combustion.
6. A method for controlling powertrain operation in a vehicle, the powertrain having an engine and an automatic transmission, the engine having at least an electrically actuated cylinder intake valve, the method comprising:
modifying a number of strokes in a cycle of a cylinder having said electrically actuated cylinder intake valve;
changing gears from a first discrete gear ratio to a second discrete gear ratio of the transmission; and
increasing engine torque during a torque phase of said gear change by changing operation of the electrically actuated cylinder intake valve, and decreasing engine torque during an inertia phase of said gear change.
7. The method of claim 6 wherein said operation of the electrically actuated cylinder valve intake includes intake valve timing.
8. The method of claim 7 wherein said operation of the electrically actuated cylinder intake valve includes a number of intake valves operating in a cylinder.
9. The method of claim 8 wherein said operation of the electrically actuated cylinder intake valve includes enabling all intake valves of a cylinder thereby reinstituting combustion in the cylinder.
10. The method of claim 7 wherein said torque is decreased by retarding spark timing.
11. The method of claim 7 wherein said torque is decreased by closing a throttle valve.
12. The method of claim 9 wherein said torque is decreased by reducing a number of cylinders carrying out combustion.
13. The method of claim 6 wherein said increasing engine torque during said torque phase of said gear change includes coordinated adjusting of valve timing of the electrically actuated intake valve and moving of a throttle plate.
14. A powertrain system for a passenger vehicle traveling on the road, comprising:
an engine, the engine having at least an electrically actuated cylinder intake valve;
an automatic transmission;
a torque converter coupled between the engine and the automatic transmission; and
a controller configured to change gears from a first discrete gear ratio to a second discrete gear ratio of the transmission; and increase engine torque during a torque phase of said gear change by changing operation of the electrically actuated cylinder intake valve, and decrease engine torque during an inertia phase of said gear change, wherein changing operation is adjusted based on an amount of slip across the torque converter.
15. The system of claim 14 wherein said controller is further configured to provide an increasing transmission input torque gradient during the torque phase, and a torque decrease during the inertia phase coupled with corresponding control of on-coming and off-going clutch timing and capacity.