A weightless factor two-stage model predictive control strategy

In this paper, a weightless factor two-stage finite set model predictive control (FCS-MPC) strategy is proposed to drive asynchronous motors with three-level Neutral Point Clamped Voltage Source Inverter (3L-NPC-VSI) as the research object, in order to achieve weightless factor control and reduce torque ripple. Firstly, in view of the difficulty of weight factor setting in traditional FCS-MPC applications, the layered optimization method is adopted to stratify the three performance indicators of voltage trip, common-mode voltage and current follow-up, so as to avoid the weight factor setting link and reduce the amount of prediction operation. Secondly, in order to further reduce the torque ripple, in the current control layer to the current following error as the principle of the least, the role of an optimal vector or optimal vector combination, and in the optimal vector combination selection process, the first vector of the combination is selected as the vector at the end of the current cycle, so as to ensure that there is only one switching state switch in each control cycle, reducing the switching loss of the two-stage FCS-MPC. Finally, simulation and experimental results verify the feasibility and effectiveness of the proposed strategy.