Hybrid powertrain speed control

A method of controlling a hybrid powertrain comprising:

• issuing a command for an engine to generate torque input to a clutch;
• issuing a command for an electric machine to output rotational speed based on an estimated torque delivered across the clutch;
• providing a feedback loop indicating a discrepancy between the commanded rotational speed and an actual rotational speed of the electric machine;
• and
• modifying the command for the electric machine to minimize the discrepancy.

A vehicle comprising:

• an engine for providing output torque to a clutch;
• an electric machine for modulating torque received from the clutch and transferred to an output shaft;
• and
• a controller programmed to (i) command a rotational output speed of the electric machine based on a predicted torque delivered across the clutch, (ii) modify the command based on the commanded output speed and an actual rotational speed of the output shaft, and (iii) disregard a discrepancy between the commanded output speed and the actual rotational speed of the output shaft in response to the rotational speed of the output shaft being less than a predetermined speed threshold.