Chattering reduction in the position control of induction motor using the sliding mode

An induction motor position control system based on sliding-mode control is presented. In sliding-mode control, the control function is discontinuous on the hyperplane, which causes harmful effects such as current harmonics and acoustic noise in a motor drive application. A low-pass filter is introduced between the sliding-mode-controller output and the motor-controller input to reduce these effects. The filter, however, makes the torque response sluggish, and the system performance may become poor as a result of a reduction in chattering. To overcome these problems, the bandwidth of the filter is allowed to vary according to the error function. The approach shows good performance, which is confirmed through computer simulation and experiments