CONTROLLING METOD FOR LOW SPEED OPERATION OF WOUND-ROTOR TYPE INDUCTION MOTOR

摘要

PURPOSE:To simply and inexpensively control the operation of an induction motor at a low speed by altering the connecting method of winding and flowing DC in the winding. CONSTITUTION:A coil 1 is connected in the same manners as an ordinary 3- phase motor, a coil 2 is reversely connected, and a coil 3 is connected to a rectifier 4 isolated from a power source. When a low speed operation is controlled in this manner, the operation at the low speed can be controlled even without using the primary voltage control and an eddy current brake, thereby eliminating a specific controller and adjustments and check and maintenance can be obviated. Accordingly, a facility cost and operation maintenance cost can be reduced.