APPARATUS OF PREVENTING INVERTER DISORDER FOR ELEVATOR

摘要

The present invention relates to a technology for preventing the inverter inverter and the motor from being burned out, in order to prevent the supply of more than the required driving voltage when the motor is running at a low speed, induction motor in the form of variable voltage, variable frequency AC voltage An inverter 102 for driving 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; In the elevator speed control device consisting of an inverter drive unit 124 for generating a pulse width modulation signal corresponding to the output signal of the control means to supply as a drive control signal of the inverter 102, 3 output from the control means And a voltage limiter 123 which sets a voltage limit value proportional to an operating frequency of the induction motor 104 when passing a phase voltage command to the inverter driver 124 and passes only a voltage command within the set value. will be.