Newer forms of automatic transmission, similar to the semi-guide gearbox and CVT use other methods of electrical power supply, and don't incorporate torque converters. There are several means of locking the torque converter clutch. These discrepancies are purpose of the hydraulic circuit managing the clutch actuation. The torque converter functions https://torqueconverterclutch20741.blogoscience.com/40246915/5-simple-statements-about-torque-converter-clutch-explained