System and method for improving the vehicle feel, fuel efficiency and performance of a hybrid vehicle

A hybrid vehicle for providing a smoother vehicle response when transitioning from an Electric Vehicle (EV) driving mode to a Hybrid Vehicle (HV) driving mode, comprising:

• a transmission;
• a battery for storing energy and for providing power to the transmission;
• a fuel converter for providing energy to the battery and for providing power to the transmission;
• a memory for storing drive force data including an amount of force to be applied to the transmission corresponding to a given pedal input and a given vehicle speed and for storing proportional scaling data including a proportional scaling number corresponding to a given state of charge of the battery;
• a battery management unit for determining a state of charge of the battery and for determining, using the stored proportional scaling data from a proportional scaling map, a proportional scaling number based on the state of charge of the battery;
• and
• an electronic control unit for receiving a pedal input and a vehicle speed, for determining, using the stored drive force data, an amount of force to be applied to the transmission based on the received pedal input and the received vehicle speed, for determining a scaled drive force by applying the determined proportional scaling number to the determined amount of force to be applied to the transmission, and for controlling a utilization of the battery and the fuel converter based on the scaled drive force when the state of charge of the battery is within a low power range for transitioning the hybrid vehicle from the EV driving mode to the HV driving mode.

A method for providing a smoother transition when transitioning from an Electric Vehicle (EV) mode to a Hybrid Vehicle (HV) mode of a hybrid vehicle, comprising:

• storing, in a memory coupled to an electronic control unit, drive force data including an amount of force to be applied to a vehicle transmission corresponding to a given vehicle speed and a given pedal input;
• storing, in the memory coupled to a battery management unit, proportional scaling data including a proportional scaling number corresponding to a given state of charge of the battery;
• determining, using the battery management unit, a state of charge of a battery used to power the vehicle transmission;
• determining, using the stored proportional scaling data from a proportional scaling map, a proportional scaling number based on the state of charge of the battery;
• determining, using the stored drive force data, an amount of force to be applied to the vehicle transmission based on a received vehicle speed and a received pedal input;
• determining, using the electronic control unit, a scaled drive force by applying the determined proportional scaling number to the determined amount of force to be applied to the vehicle transmission;
• and
• controlling, using the electronic control unit, a utilization of the battery and a fuel converter based on the scaled drive force when the state of charge of the battery is within a low power range for transitioning the hybrid vehicle from the EV driving mode to the HV driving mode.