Methods and systems for torque transitioning
Methods and systems are provided for torque application during a deceleration event initiated via a shift lever direction change request. In one example, adjusting a deceleration torque towards a traction torque of a going to direction at a vehicle standstill based on an actual vehicle speed and an accelerator pedal position when the actual vehicle speed is below a threshold vehicle speed and a shift lever position is adjusted from a forward position to a reverse position.
1 . A method, comprising:
adjusting a regenerative torque towards a traction torque at a vehicle standstill based on an actual vehicle speed and an accelerator pedal position when the actual vehicle speed is below a threshold vehicle speed and a shift lever position is adjusted from a forward position to a reverse position.
2 . The method of claim 1 , further comprising applying a max torque as regenerative torque in response to the actual vehicle speed being greater than or equal to the threshold vehicle speed.
3 . The method of claim 2 , further comprising decelerating a vehicle, wherein the regenerative torque is in a coming from direction and the traction torque is in a going to direction relative to a direction of vehicle travel.
4 . The method of claim 1 , wherein adjusting the regenerative torque is non-linear.
5 . The method of claim 1 , further comprising applying the traction torque prior to a vehicle standstill.
6 . The method of claim 1 , wherein the regenerative torque resists vehicle motion.
7 . A system, comprising:
a vehicle;
a battery coupled to an electric machine;
a shift lever coupled to a controller; and
an accelerator pedal coupled to the controller;
the controller comprising computer-readable instructions stored on memory thereof that when executed cause the controller to:
apply torque as regenerative torque when regenerative braking is occurring and a vehicle speed is greater than or equal to a threshold speed; and
transition a percentage of regenerative torque to traction torque when regenerative braking is occurring and the vehicle speed is less than the threshold speed.
8 . The system of claim 7 , wherein the transition follows an exponential curve.
9 . The system of claim 7 , wherein the transition follows a logarithmic curve.
10 . The system of claim 7 , wherein the transition follows a map plotting a vehicle speed, a torque command, and a position of the accelerator pedal.
11 . The system of claim 7 , wherein the instructions further enable the controller to adjust the regenerative torque to be equal to the traction torque at a vehicle stop.
12 . The system of claim 7 , wherein a rate of the transition of the regenerative torque decreases as the vehicle approaches a vehicle stop after the vehicle speed is less than the threshold speed.
13 . The system of claim 7 , wherein the regenerative torque resists vehicle motion and the traction torque promotes vehicle motion.
14 . The system of claim 7 , wherein a torque sign is maintained during an entirety of the transition.
15 . The system of claim 7 , wherein the instructions further enable the controller to adjust the transition based on a position of the accelerator pedal, the adjusting based on a map plotting a vehicle speed, a torque command, and the position of the accelerator pedal.
16 . A system for an electric vehicle, comprising:
a battery coupled to an electric machine;
a shift lever coupled to a controller; and
an accelerator pedal coupled to the controller; wherein
the controller comprises computer-readable instructions stored on memory thereof that when executed cause the controller to:
apply torque as regenerative torque when regenerative braking is occurring and a vehicle speed is greater than or equal to a threshold speed; and
transition a percentage of regenerative torque to traction torque when regenerative braking is occurring and the vehicle speed is less than the threshold speed, wherein the transition is based on a map plotting a vehicle speed, a torque command, and a position of the accelerator pedal.
17 . The system of claim 16 , wherein the transition follows a parametrized curve.
18 . The system of claim 16 , wherein the percentage increases as the vehicle approaches a vehicle stop.
19 . The system of claim 18 , wherein an amount of regenerative torque is equal to an amount of traction torque at the vehicle stop.
20 . The system of claim 16 , wherein the instructions further enable the controller to adjust the transition in response to the accelerator pedal being depressed.