Patent ID: 8348020

Claim:
An elevator control device comprising: an AC motor; a motor controller configured to calculate a voltage command required for driving an elevator cage through the AC motor; a carrier frequency switch circuit configured to output a carrier frequency and a torque limit value corresponding to the carrier frequency based on an input torque command, the carrier frequency switch circuit being configured to store a relation between the torque limit value and an allowable carrier frequency, the relation including an allowable range of the torque limit value and the carrier frequency, the carrier frequency switch circuit outputting the torque limit value and the carrier frequency which are within the allowable range if the input torque command is out of the allowable range; a torque limiter configured to limit the input torque command to a smaller one of a preset torque limit value and the torque limit value output from the carrier frequency switch circuit; and a power converter configured to perform PWM control based on the voltage command and the carrier frequency which is output from the carrier frequency switch circuit and configured to supply an AC power to the AC motor.