Method for suppressing speed ripple by using torque compensator based on activation function

摘要

Disclosed is a method for suppressing a speed ripple occurring during an operation of an AC motor by using a torque compensator based on an activation function. The method includes the steps of calculating a speed error ω_err based on a reference speed ω_ref and an actual speed ω_act; calculating a controller output T_rm by using the speed error ω_err as an input of a PI control and an operation of a compensated torque T_com; and determining a torque variation based on the controller output T_rm and a reference torque T_ref and operating the torque variation in relation to an anti-windup gain K_a to use torque variation as an input of an integral (I) control. The method suppresses the speed ripple by compensating for the torque ripple through a controller which calculates the compensated torque by taking the signs of the speed error and the differential speed error into consideration.