Control apparatus for A.C. elevator

摘要

A control apparatus for an A.C. elevator having a variable voltage and variable frequency inverter for driving an induction motor coupled to a cage of the elevator, a control device for controlling the inverter in accordance with a deviation between a speed signal detected from the induction motor and a speed command signal having a preset value, and an abnormality detection device for interrupting feed of the A.C. power to the induction motor upon detecting that a slip frequency command corresponding to the deviation is greater than a predetermined set value and continues exceeding the predetermined set value in excess of a predetermined period of time.