Method and apparatus for managing charge depletion in a plug-in hybrid vehicle

摘要

A plug-in hybrid vehicle includes a hybrid powertrain system and an energy storage device. A method for operating the hybrid powertrain system includes initially operating the hybrid powertrain system in a charge-depletion mode to reduce a state-of-charge (SOC) of an energy storage device. In response to an operator request, the hybrid powertrain system operates in an opportunity charging mode to opportunistically charge the energy storage device to increase the SOC of the energy storage device during a trip prior to achieving a minimum SOC that is associated with triggering operation in a charge sustaining mode.

主权项

1. A method for operating a hybrid powertrain system in a plug-in hybrid vehicle, comprising:
initially operating the hybrid powertrain system in a charge-depletion mode to reduce a state-of-charge (SOC) of an energy storage device; monitoring the SOC of the energy storage device; operating the hybrid powertrain system in a charge-sustaining mode only when the SOC of the energy storage device decreases to a predetermined minimum SOC threshold, the charge-sustaining mode including operating an internal combustion engine and an electric machine of the hybrid powertrain system to sustain the SOC of the energy storage device at or above the predetermined minimum SOC threshold; operating the hybrid powertrain system in the charge-depletion mode when the monitored SOC of the energy storage device is greater than the predetermined minimum SOC threshold; in response to an operator request for a HOLD+SOC strategy, determining if the SOC of the energy storage device is less than a predetermined HOLD+SOC maximum threshold associated with operating the hybrid powertrain system in an opportunity charging mode; if the SOC of the energy storage device is greater than the predetermined HOLD+SOC maximum threshold operating the hybrid powertrain system to maintain the SOC of the energy storage device; if the SOC of the energy storage device is less than the predetermined HOLD+SOC maximum threshold, iteratively determining whether operating conditions for operating the hybrid powertrain system in the opportunity charging mode have been met, said operating conditions having been met when an internal combustion engine of the hybrid powertrain system is operating at a desired efficiency and no operating faults are present;
operating the hybrid powertrain system in an opportunity charging mode, comprising operating the internal combustion engine to generate torque to charge the energy storage device, only when the SOC of the energy storage device is less than a predetermined maximum SOC threshold and operating conditions for operating the hybrid powertrain system in the opportunity charging mode have been met, and charging the energy storage device to increase the SOC of the energy storage device up to the predetermined HOLD+SOC maximum threshold during a trip prior to the SOC of the energy storage device achieving the predetermined minimum SOC threshold that is associated with triggering operation of the hybrid powertrain system in the charge-sustaining mode; andoperating the hybrid powertrain system to maintain the SOC of the energy storage device when the SOC of the energy storage device is less than the predetermined maximum SOC threshold, but operating conditions for operating the hybrid powertrain system in the opportunity charging mode have not been met; andcontinuing operating the hybrid powertrain system to maintain the SOC of the energy storage device when operating conditions for operating the hybrid powertrain system in an opportunity charging mode have not been met, and to opportunistically charge the energy storage device when operating conditions for operating the hybrid powertrain system in an opportunity charging mode have been met, until the SOC of the energy storage device has increased to the predetermined HOLD+SOC maximum threshold.