the line 15 the mode of operation of the hydrodynamic torque converter of fig3 corresponds to the mode of operation of the hydrodynamic torque converter of fig1 and 2 unlike the design described in fig1 and 2 the torque converter in fig3 contains one pressure sensor 17 which determines the pressure acting upon the first piston area 4 and supplies it to an electronic control unit 18 the electronic control unit issues a signal to a proportional valve 19 and controls it according to a single rotational speed sensor 20 and nominal value settings 21 and correction factors 22 the proportional valve 19 supplies the space 14 with pressure medium and pressurizes the second piston area 5 in order to apply to the clutch 2 a defined force via the piston 3 the converter housing 1 is connected with a prime mover not shown and driven the primary clutch 2 connects the housing 1 with the pump impeller 6 the turbine impeller 7 can be connected via a converter bridge clutch 23 with the housing 1 upon the first piston area 4 acts the variable pressure within the housing which depends on the operational parameters and the operational state of the converter the first piston area 4 and the space 10 are connected via the line 9 with a valve or.