Inverter failure prevention device of elevator

摘要

The present invention relates to a technique for preventing an inverter and a motor of an elevator from being burned out. In order to prevent a driving voltage from being supplied more than necessary when an electric motor is running at a low speed, an alternating-An inverter 102 for driving the electric motor 104 to drive the car 108 at a desired speed; Control means for detecting each phase current of the induction motor 104 through current sensors 103A-103C and generating a three-phase voltage command; And an inverter driving unit (124) for generating a pulse width modulation signal corresponding to an output signal of the control unit and supplying the pulse width modulation signal to the drive control signal of the inverter (102), characterized in that the control unit And a voltage limiter 123 for setting a voltage limit value proportional to the operating frequency of the induction motor 104 when passing the phase voltage command to the inverter driving unit 124 and passing only a voltage command within the set value will be.