Torque control modeling for torque control of hybrid electric powertrains

A method that generates and transfers drive torque to a driveline of a hybrid electric vehicle, the driveline including an engine having an engine output, an electric motor having a first electric motor output, a clutch that selectively disengages the engine output from a remainder of the electrified powertrain, a torque converter that transfers rotating power from at least one of the engine and the electric motor to a transmission, and a controller, the method comprising:

• receiving, at the controller, an impeller speed and a turbine speed of the torque converter;
• determining, at the controller, a target turbine torque;
• determining, at the controller, coefficients as a function of the impeller speed, turbine speed and target turbine torque based on implementation of a Kalman filter as a function of a positive slip speed of the torque converter;
• calculating impeller torque and lock-up clutch torque based on the positive slip speed of the torque converter;
• updating, at the controller, an adaptive lookup table based on the coefficients;
• and
• determining, at the controller, an adapted turbine torque based on the updated adaptive lookup table.