What this means is that there is a lot of electric power dropped in the torque converter, dissipated as heat. To be able to enhance its efficiency, producers included a lock-up clutch for the torque converter. Torque converter equations of movement are ruled by Leonhard Euler's eighteenth century turbomachine equation: https://emilianocujxj.dgbloggers.com/34419383/the-definitive-guide-to-torque-converter-clutch