CONTROLLABLE A C ELECTRIC MOTOR DRIVE Russian patent published in 1995 - IPC

FIELD: electrical engineering. SUBSTANCE: driving mechanism 1, for instance hydraulic pump, is coupled to shaft of asynchronous motor 2 with wound rotor. Phase windings of rotor of asynchronous motor 2 are connected in star through windings 3 of frequency-dependent resistors. Electric motor is provided with bias winding 4 dropped in slots of stator and shell of monmagnetic material pressed onto stator iron. Bias winding is connected to output of D. C. source 6 linked with input to output of master unit 7 of rotational speed. Stator windings of asynchronous motor 2 are connected to power supply network of alternating current through static voltage to-current converter 5. As there are no nonlinear elements in supply circuits of stator winding form of voltage curve across terminals of stator winding and acrossinput terminals of static converter 5 is sinusoidal which ensures good power characteristics of proposed structure of controllable electric motor drive. EFFECT: good power characteristics of cotrollable electric motor drive. 2 dwg