Patent ID: 6378636
Filing Date: 2002-04-30
Classification: B60K,B60L,B60T,B60W,Y02T,Y10S

Abstract:
A control system for a vehicle to provide a negative torque to a powertrain with an electric motor, comprising:an accelerator means that is operator-movable through a range of positions from a released position to a full power position; a means to transmit accelerator means position to a vehicle system control when the accelerator means is at the released position; a means to transmit a powertrain state to the vehicle system control; a control module within the vehicle system control to receive an output from the means to transmit accelerator position and an output from the means to transmit the powertrain state, wherein the control module determines when the accelerator means is at the released position and the electric motor is the sole source of torque to the powertrain; and a hierarchical coast-down strategy means that receives the output from the control module and commands a negative torque means, based on a plurality of vehicle operating conditions, to the vehicle powertrain through a plurality of methods of supplying negative torque when the control module has determined the accelerator is released and the electric motor is the sole torque provider to the powertrain so that the negative torque means maintains optimal energy recovery and deceleration is consistent regardless of the plurality of vehicle operating conditions.