Vehicle operation mode systems and methods

Abstract

A system for controlling a mode of operation of a vehicle having a rechargeable energy storage system (RESS), an engine, and a drive motor coupled to the RESS and the engine, the drive motor selectively powered by at least one of the RESS and the engine includes a controller operable to adjust the vehicle to operate in a plurality of operating modes including a first mode in which the drive motor is powered by the RESS, a second mode in which the drive motor is powered more by the engine than the RESS. When the second mode of operation is selected, controller is configured to operate the engine as necessary to maintain the RESS at or above a predetermined state of charge.

What is claimed is: 
     
         1 . A system for controlling a mode of operation of a driver operated vehicle having a rechargeable energy storage system (RESS), an engine configured to drive an electrical generator, and a drive motor coupled to the RESS and the engine, the drive motor selectively powered by at least one of the RESS and the engine, the system comprising:
 a controller operable to adjust the vehicle to operate in at least two operating modes including a first mode of operation in which the drive motor is powered only by the RESS and a second mode of operation in which the drive motor is powered by electrical power provided by the engine driven generator;   a mechanism for the driver to select either the first mode of operation or the second mode of operation;   wherein when the driver operates the mechanism to select the first mode of operation the controller is configured to maintain the system in the first mode of operation and ensure that the only power source for the drive motor is the RESS regardless of the power demanded by the driver;   wherein when the driver operates the mechanism to select the second mode of operation the controller is configured to operate the engine to generate electric power for the drive motor;   wherein, when the second mode of operation is selected, controller is configured to operate the engine as necessary to maintain the RESS at or above a predetermined state of charge.   
     
     
         2 . The system of  claim 1 , wherein the controller is configured to automatically shift the vehicle to the second mode of operation when the RESS reaches a target state of charge threshold. 
     
     
         3 . The system of  claim 2 , wherein the predetermined state of charge is greater than the target state of charge threshold. 
     
     
         4 . The system of  claim 1 , wherein the mechanism for selecting the mode of operation of the vehicle includes a driver interface that located on the steering wheel. 
     
     
         5 . The system of  claim 1 , further comprising a second mechanism for the driver to select a first mode of braking operation; and wherein in the first mode of braking operation a first amount of regenerative braking is provided when a brake pedal is not depressed. 
     
     
         6 . The system of  claim 5 , wherein the second mechanism is configured for the driver to select a second mode of braking operation; and wherein in the second mode of braking operation a second amount of regenerative braking is provided when the brake pedal is not depressed. 
     
     
         7 . The system of  claim 6 , wherein the second amount of regenerative braking is greater than the first amount of regenerative braking. 
     
     
         8 . The system of  claim 5 , wherein the second mechanism includes a driver interface located on the steering wheel. 
     
     
         9 . A system for controlling a mode of operation of a driver operated vehicle having a rechargeable energy storage system (RESS), an engine configured to drive an electrical generator, and a drive motor coupled to the RESS and the engine, the drive motor selectively powered by at least one of the RESS and the engine, the system comprising:
 a controller operable to adjust the vehicle to operate in at least two operating modes including a first mode of operation in which the drive motor is powered only by the RESS and a second mode of operation in which the drive motor is powered by electrical power provided by the engine driven generator;   a mechanism for the driver to select either the first mode of operation or the second mode of operation;   wherein when the driver operates the mechanism to select the second mode of operation the controller is configured to operate the engine to generate electric power for the drive motor;   wherein, when the second mode of operation is selected by the driver, controller is configured to operate the engine as necessary to maintain the RESS at an existing state of charge level present when the second mode of operation is selected by the driver.   
     
     
         10 . The system of  claim 9 , wherein when the driver operates the mechanism to select the first mode of operation the controller is configured to maintain the system in the first mode of operation and ensure that the only power source for the drive motor is the RESS regardless of the power demanded by the driver. 
     
     
         11 . The system of  claim 9 , wherein, when the first mode of operation is selected by the driver, the controller is configured to automatically shift the vehicle to the second mode of operation when the RESS reaches a target state of charge threshold. 
     
     
         12 . The system of  claim 9 , wherein the mechanism for selecting the mode of operation of the vehicle includes a driver interface that located on the steering wheel. 
     
     
         13 . The system of  claim 9 , further comprising a second mechanism for the driver to select a first mode of braking operation; and wherein in the first mode of braking operation a first amount of regenerative braking is provided when a brake pedal is not depressed. 
     
     
         14 . The system of  claim 13 , wherein the second mechanism is configured for the driver to select a second mode of braking operation; and wherein in the second mode of braking operation a second amount of regenerative braking is provided when the brake pedal is not depressed. 
     
     
         15 . The system of  claim 14 , wherein the second amount of regenerative braking is greater than the first amount of regenerative braking. 
     
     
         16 . The system of  claim 13 , wherein the second mechanism includes a driver interface located on the steering wheel.