Encoderless Predictive Flux Control of Three-level NPC Converter-fed Induction Motor with SMO

In this work, we proposed an encoderless finite control set predictive flux control (FCS-PFC) method for an induction motor (IM) fed by a three-level neutral-point clamped (3L-NPC) power converter. The FSC-PFC employs stator flux vector as control objective to eliminate the weighting factor(s) between torque and flux commonly used in the predictive torque control (PTC) approach. An improved sliding-mode observer (SMO) is applied to achieve encoder-less control, where the feedback speed signal is not necessary, which is novel add-on to the state-of-the-art solutions. Simulation and experimental results verify the effectiveness of the proposed encoderless PFC method.