DEVICE FOR CONTROLLING THREE-PHASED ASYNCHRONOUS ELECTRIC MOTOR Russian patent published in 2006 - IPC H02P3/24 

FIELD: electric engineering, possible use for engineering electric drives of generic industrial mechanisms.

SUBSTANCE: device for controlling three-phase asynchronous electric motor additionally contains braking contact with four closing contacts, bridging capacitor, dynamic braking contactor with two closing contacts, five resistors, and three auxiliary capacitors. Two contacts of braking contactors are connected to first outputs of phase windings of stator, and third contact is connected thereto and to bridging capacitor, second winding of which is connected to anode group of bridge diodes, which through fourth contact of braking contactor is connected to cathode group of bridge diodes. Resistors are connected to input of bridge and to second outputs of phase windings, combined to form a star. Between zero bus and star of resistors, executing organ is connected. To outputs of additional resistor, appropriately through diodes and resistors, auxiliary capacitors are connected. Minus plates of first and second auxiliary capacitors through first contact of dynamic braking contactor are connected to first outputs of phase windings. Plus plates of second and third auxiliary capacitors are connected through second closing contact of dynamic braking contactor to output of the bridge. Second plates of first and third auxiliary capacitors are connected to aforementioned zero bus.

EFFECT: increased reliability, increased intensiveness and increased efficiency of braking and improved protection from loss of one or more phases.

1 dwg