EMERGENCY PROTECTIVE GEAR OF THREE-PHASE INDUCTION-MOTOR DRIVE FOR FARMING MECHANISMS Russian patent published in 1997 - IPC

FIELD: rural electromechanics; submersible electric drives and all farming mechanisms using induction-motor drives where motor shaft is inaccessible or hard-to-get-at technologically. SUBSTANCE: protective gear has two triacs 1 inserted in stator circuit, three-phase-to-split-phase voltage converter unit 2, three-phase-to-split-phase current converter unit 3, and torque unit 5 whose output is connected to input of logic switch 6. Output of the latter is coupled with input of triac control unit 7. Novelty is that unit determining mechanical parameters of motor rotor is made in the form of current and voltage converter, and torque-computing unit. EFFECT: enlarged functional capabilities. 4 dwg