ALTERNATING-CURRENT DRIVE Russian patent published in 2004 - IPC

FIELD: electrical engineering; variable-speed drives.

SUBSTANCE: proposed ac drive that can be used under severe initial starting conditions and in polluted and humid atmospheres (electric traction, mine hoists, and the like), as well as where comprehensive speed control and high overload capacity are required depends for its operation on implementing control mechanism enabling acquiring of properties intrinsic to synchronous-motor drives. It has slip-ring motor and induction exciter whose shafts are rigidly intercoupled; stator windings are connected to outputs of respective frequency changers and rotor windings are interconnected in reverse phase sequence. Output of induction-motor stator voltage amplitude setting unit is connected to one of control inputs of induction-motor frequency changer. Output of induction-motor stator phase voltage sensor is connected through shaping filter to second control input of induction-motor frequency changer. First output of field frequency setting element is connected to one of control inputs of induction-exciter frequency changer. Synchronizing unit has rotor speed computing device whose first input is connected to second output of shaping filter and output, to one of inputs of rotor speed deviation sensor; second input of the latter is connected to first output of rotor speed setting element whose second output is connected to input of stator voltage amplitude setting unit. Output of rotor speed deviation sensor is connected through voltage regulator to second control input of induction-exciter frequency changer.

EFFECT: enlarged functional capabilities.

1 cl, 1 dwg