Patent ID: 7472769

Claim:
A hybrid vehicle control system comprising: an engine; a motor/generator; a first clutch configured and arranged to change a first torque transfer capacity between the engine and the motor/generator; a second clutch configured and arranged to change a second torque transfer capacity between the motor/generator and at least one drive wheel by selectively maintaining a target torque transfer capacity calculated based on a target drive force when the second clutch is transferring power from at least the motor/generator to the drive wheel; and a controller configured to selectively control the first and second clutches to switch between an electric drive mode in which the first clutch is released and the second clutch is engaged, and a hybrid drive mode in which both the first and second clutches are engaged, the controller being configured to determine and set the target torque transfer capacity of the second torque transfer capacity including a motor/generator torque component and an engine torque component with the motor/generator torque component being determined based on a motor/generator torque and a torque transfer capacity margin allowance for the motor/generator torque and the engine torque component being determined based on an engine torque and a torque transfer capacity margin allowance for the engine torque when the drive wheel is driven at least by the motor/generator.