Attached you will find a parellel hybrid design of a Porsche Cayenne hybrid. From what I understand,its the ICE(combustion engine) that is finally delivering power to the differentials.This power is 'substantiated' by power delivered from an electric motor.As you can see from the diagram,the motor is connected at the output end of the ICE via a double clutch. This is where I get confused: If I do want to add-up power by switching my motor into operation,my O/P end of the shaft would spin faster.Won't this effect the functioning of the ICE? i.e the piston velocity will increase considerably. This would mean I have lesser time to combust=>lesser power. So,how does the motor power get heterodyned with the power from the ICE?