METHOD OF AC MOTOR BRAKING Russian patent published in 2012 - IPC H02P3/24 

FIELD: electricity.

SUBSTANCE: current is additionally supplied into a motor's stator winding, which is induced by the rotor's rotation EMF, the value of which (current) is controlled by current sensors and adjusted by variation of the conductivity angle of additional semiconductor elements. Increase of the motor efficiency in the braking mode is achieved by application of the rotor's electromagnet energy in the period of braking, besides, supply of the additional rotor energy is carried out at the moment the single half-wave rectified current supplied to the stator winding from the supply grid is equal to zero. According to the proposed method of braking, first the single half-wave rectified current from the supply grid is supplied into de-energised windings of the stator, and the moment this current passes via zero, the single half-wave rectified current is supplied induced from the rotor's rotation EMF, via an additional semiconductor element and a resistor. The total single half-wave rectified current develops a braking moment, at the same time the value of current induced in the stator from EMF of the rotor's rotation is controlled by the current sensors and adjusted by variation of the conductivity angle of semiconductor elements.

EFFECT: increased efficiency of braking and higher motor efficiency in braking mode.

3 cl, 2 dwg