DEVICE FOR PROTECTING SYNCHRONOUS MOTOR AGAINST ASYNCHRONOUS RUNNING Russian patent published in 1994 - IPC

FIELD: electrical engineering. SUBSTANCE: device has asynchronous running detector whose inputs are connected to voltage of main power supply bus section and to synchronous motor current. Its output is connected through delay element to synchronous motor to synchronous motor switch and slip angle and polarity monitoring unit. Its inputs are connected to voltage of main power supply bus section and to like-polarity voltage of stand-by supply bus section. OR gate is connected at its inputs to outputs of asynchronous running detector and slip angle and polarity monitoring unit, and through input to automatic resynchronizing system of synchronous motor. EFFECT: improved reliability of asynchronous running protection. 2 dwg