Integral variable structure controller for current control of PWM inverter-fed AC drives

A new current control technique is presented for three-phase PWM inverterfed AC drives. The features of several existing approaches are analyzed and an integral variable structure control (IVSC) is proposed as an effective way of realizing the high-performance current control. The characteristics of the proposed IVSC are investigated and the design method is presented for the AC drives associated with a voltage-fed PWM inverter. By employing the proposed control, a robust control performance against the parameter uncertainties is obtained in both transient and steady states. The proposed control is applied to the three-phase induction motor drives and the performance improvement is well demonstrated through the simulations and experiments.