Stator flux based space-vector modulation and closed loop control of the stator flux vector in overmodulation into six-step mode

Abstract

This paper presents closed loop control of stator flux vector in a wide operating range that can be used in torque control. A predictive control achieves zero phase error at constant switching frequency. Space vector modulation based on stator flux error vector is used to achieve control of stator flux over the entire range including overmodulation and six-step. During dynamics the fastest possible flux vector change is employed similar to the direct torque control. Experimental results are provided for a wide speed range and effect of parameter variation is studied.