A method for operating a powertrain of a hybrid vehicle is provided. The method includes outputting via a controller an engine speed command that is based on a predicted impeller speed of a torque converter and corresponds to the accelerator tip-in to output a torque from the engine to wheels of the vehicle in response to detection of an accelerator pedal tip-in greater than a predetermined threshold. The method may also include accessing a history of impeller speed outputs of the hybrid vehicle to obtain the predicted impeller speed. The engine speed command may set engine speed substantially equal to or greater than the predicted impeller speed. The predetermined threshold may be based on a driver requested torque output of the wheels in which torque from the torque converter to the wheels results in saturation.

A method for learning engine clutch delivery torque of a hybrid vehicle includes: determining, by a controller, whether power transference of a transmission transmitting output from an engine of the vehicle and a motor of the vehicle is interrupted; controlling, by the controller, a speed of the motor to be maintained at a first speed when the power transference of the transmission is interrupted; calculating, by the controller, a first delivery torque of an engine clutch that connects the engine with the motor or disconnects the engine from the motor, based on the first speed and a second speed of the motor which is generated after the engine clutch is engaged; controlling, by the controller, the speed of the motor to be maintained at the second speed by releasing the engine clutch after the first delivery torque is calculated; and calculating, by the controller, a second delivery torque of the engine clutch based on the second speed and a third speed of the motor which is generated after the engine clutch is engaged.

A method for learning engine clutch delivery torque of a hybrid vehicle includes: determining, by a controller, whether power transference of a transmission transmitting output from an engine of the vehicle and a motor of the vehicle is interrupted; controlling, by the controller, a speed of the motor to be maintained at a first speed when the power transference of the transmission is interrupted; calculating, by the controller, a first delivery torque of an engine clutch that connects the engine with the motor or disconnects the engine from the motor, based on the first speed and a second speed of the motor which is generated after the engine clutch is engaged; controlling, by the controller, the speed of the motor to be maintained at the second speed by releasing the engine clutch after the first delivery torque is calculated; and calculating, by the controller, a second delivery torque of the engine clutch based on the second speed and a third speed of the motor which is generated after the engine clutch is engaged.

A method is provided to control a hybrid powertrain to achieve a desired engine speed in a combustion engine, said powertrain comprising: a gearbox with input and output shafts with the combustion engine connected to the input shaft; a first planetary gear connected to the input shaft and a first main shaft; a second planetary gear connected to the first planetary gear and a second main shaft; first and second electrical machines respectfully connected to the first and second planetary gears; first gear pair connected with the first main shaft; and second gear pair connected with the second main shaft. The method comprises a) ensuring that two rotatable components in the first planetary gear are connected; b) ensuring that all rotatable components in the second planetary gear are disconnected; c) ensuring that a gear is engaged in the first gear pair, d) ensuring that the second gear pair is disconnected; e) controlling the second electrical machine so that a desired torque is achieved in the output shaft; f) controlling the combustion engine to a desired engine speed; and g) controlling the first electrical machine so that a desired total power consumption for the first and the second electrical machines is achieved.