Improved Weighting Factor Selection for Predictive Torque Control of Induction Motor Drive Based on a Simple Additive Weighting Method

Abstract

A predictive torque control (PTC) technique is emerging as an effective alternative for induction motor drives because of its simple structure, ability to include control parameters directly into the cost function, and fast dynamic response. To implement PTC for induction motor drive, both stator flux and torque errors are predicted for each switching state of the converter and the combined error is determined with the help of cost function using a suitable stator flux weighting factor. However, the selection of suitable weighting factor is a tedious and complex task. In this paper, a simple additive weighting method is introduced in the cost function optimization to simplify the weighting factor selection process. To observe the effectiveness of the proposed control algorithm, both simulation and experimental results are presented for a two-level voltage-source-inverter-fed induction motor drive and compared with conventional PTC under various operating conditions. The proposed control technique achieves low-torque ripple along with reduced switching frequency.