A FAST MOTOR STOPPING CONTROL APPARATUS IN AN INVERTER FOR AN AC MOTOR AND CONTROL METHOD THEREOF

摘要

An apparatus and a method of controlling a sudden stop of a motor in an inverter for an AC motor are provided to perform fast deceleration and stable control regardless of a size of inertia of the motor and a control time. A minute deceleration frequency generating unit(10) outputs a frequency variation per unit time(Deltafreq) obtained by proportional-integral of a difference value obtained by subtracting the current DC voltage from reference voltage, within a limit of a frequency variation per maximum unit time. A minute deceleration frequency adjusting unit(20) outputs the frequency variation per unit time without change as a frequency variation per first adjusted unit time(Deltafreq1) or zero to maintain a speed of a motor when the frequency variation per unit time is greater than or equal to zero and outputs a half of the frequency variation per unit time as a frequency variation per second adjusted unit time(Deltafreq2) or zero to maintain the speed of the motor when the frequency variation per unit time is less than zero. A final minute deceleration frequency command and output voltage command generating unit(30) outputs the frequency variation per first adjusted unit time or the frequency variation per second adjusted unit time outputted from the minute deceleration frequency adjusting unit as a final minute deceleration frequency command(Deltafreq*).