Abstract: A method for learning a touch point of an engine clutch of a hybrid electric vehicle including a motor connected to a transmission and an engine selectively connected to the motor through the engine clutch includes determining whether a learning condition of the touch point of the engine clutch is satisfied, releasing a transmission clutch and controlling a motor speed when the learning condition is satisfied, increasing a coupling pressure of the engine clutch when a change amount of the motor speed is less than a first predetermined value, comparing a change amount of a motor torque according to the increased coupling pressure of the engine clutch with a second predetermined value, and learning the touch point of the engine clutch when the change amount of the motor torque is greater than or equal to the second predetermined value.

Abstract: A method for learning a touch point of an engine clutch of a hybrid electric vehicle including a motor connected to a transmission and an engine selectively connected to the motor through the engine clutch includes determining whether a learning condition of the touch point of the engine clutch is satisfied, releasing a transmission clutch and controlling a motor speed when the learning condition is satisfied, increasing a coupling pressure of the engine clutch when a change amount of the motor speed is less than a first predetermined value, comparing a change amount of a motor torque according to the increased coupling pressure of the engine clutch with a second predetermined value, and learning the touch point of the engine clutch when the change amount of the motor torque is greater than or equal to the second predetermined value.

Abstract: A method for calculating a regenerative braking amount of a hybrid electric vehicle includes calculating a first possible available charging power of a motor when regenerative braking of the hybrid electric vehicle is required; calculating a second possible charging power of the motor by using the first possible charging power of the motor; converting the second possible charging power of the motor to a torque of a wheel axle; calculating an available amount of regenerative braking by reflecting a coasting torque on the torque of the wheel axle; generating a motor torque command based on the available amount of regenerative braking; and calculating a final regenerative braking amount by monitoring a real motor torque according to the motor torque command and correcting an error.

Abstract: A method and apparatus for operating a plug-in hybrid electric vehicle are provided. The includes setting an initial distance until charge (DUC) and calculating a current DUC by subtracting a travel distance of the vehicle from the initial DUC after the initial DUC is set. A current distance to empty (DTE) is calculated based on a current state of charge (SOC) of a battery and the current SOC of the battery is compared with a reference SOC. The current DUC is compared with the current DTE when the current SOC is greater than the reference SOC. Thus, whether a high speed condition or a high load condition is satisfied is determined when the current DUC is greater than the current DTE. A driving mode of the vehicle is then set to be a charge sustaining (CS) mode when the high speed condition or the high load condition is satisfied.

Abstract: A method and apparatus for operating a plug-in hybrid electric vehicle are provided. The includes setting an initial distance until charge (DUC) and calculating a current DUC by subtracting a travel distance of the vehicle from the initial DUC after the initial DUC is set. A current distance to empty (DTE) is calculated based on a current state of charge (SOC) of a battery and the current SOC of the battery is compared with a reference SOC. The current DUC is compared with the current DTE when the current SOC is greater than the reference SOC. Thus, whether a high speed condition or a high load condition is satisfied is determined when the current DUC is greater than the current DTE. A driving mode of the vehicle is then set to be a charge sustaining (CS) mode when the high speed condition or the high load condition is satisfied.

Abstract: An engine clutch transfer torque determining apparatus of a vehicle includes: a power source including an engine and a driving motor; an engine clutch that is located between the engine and the driving motor to selectively connect the engine to the driving motor; and a vehicle controller that controls release or engagement of the engine clutch to implement a driving mode, wherein the vehicle controller releases a clutch hydraulic pressure in the engine clutch when a running state of the vehicle satisfies a transfer torque determining advancing condition, controls a speed of the motor and a speed of the engine while maintaining a speed difference between the motor and the engine in a predetermined relative speed range, and determines a transfer torque of the engine clutch based on a clutch hydraulic pressure and a clutch input torque when the engine clutch slips.

Abstract: A method for calculating a regenerative braking amount of a hybrid electric vehicle includes calculating a first possible available charging power of a motor when regenerative braking of the hybrid electric vehicle is required; calculating a second possible charging power of the motor by using the first possible charging power of the motor; converting the second possible charging power of the motor to a torque of a wheel axle; calculating an available amount of regenerative braking by reflecting a coasting torque on the torque of the wheel axle; generating a motor torque command based on the available amount of regenerative braking; and calculating a final regenerative braking amount by monitoring a real motor torque according to the motor torque command and correcting an error.

Abstract: An engine clutch transfer torque determining apparatus of a vehicle includes: a power source including an engine and a driving motor; an engine clutch that is located between the engine and the driving motor to selectively connect the engine to the driving motor; and a vehicle controller that controls release or engagement of the engine clutch to implement a driving mode, wherein the vehicle controller releases a clutch hydraulic pressure in the engine clutch when a running state of the vehicle satisfies a transfer torque determining advancing condition, controls a speed of the motor and a speed of the engine while maintaining a speed difference between the motor and the engine in a predetermined relative speed range, and determines a transfer torque of the engine clutch based on a clutch hydraulic pressure and a clutch input torque when the engine clutch slips.

Abstract: Disclosed is a system and method that control an electric vehicle to engage a brake and to output torque of a motor after completely stopping an electric vehicle on a slope by the brake and controlling the torque of the motor to be 0 when the torque of the motor is a positive value and the velocity of the motor is a negative value when the electric vehicle is rolling backwards down a hill during uphill driving, such that safety and reliability of the electric vehicle can be improved when the electric vehicle is driving uphill on a slope.

Abstract: A control method for a powertrain of a hybrid vehicle executing a compound split mode where a first carrier and a second ring gear are selectively connected. More specifically, a controller, determines a target torque of the second motor/generator based on a gear ratio of the first sun gear and the first ring gear, a gear ratio of the second sun gear and the second ring gear, a demand torque of the powertrain, and an output torque of the first motor/generator; determines a compensation value based on a target speed of the engine and a current speed of the engine; and determines a final torque of the second motor/generator based on the target torque of the second motor/generator and the compensation value, and controlling the second motor/generator according to the final torque of the second motor/generator.

Abstract: Disclosed is a control system and method for a hybrid vehicle. More specifically, system is configured to calculate a target speed of the first motor/generator according to output speed of the engine, calculate an error speed between a real speed and the target speed of the first motor/generator, apply a compensation value to the error speed, and calculate a target torque of the first motor/generator by applying proportional gain and integrated gain to the compensated error speed of which the compensation value is applied. Accordingly, an error speed is detected between a target speed and a real speed of the first motor/generator according to driving conditions of the engine and the first motor/generator quickly reaches the target speed and the vibration is prevented by applying a compensation value to the error speed such that the control efficiency of entire shifting system is improved.