Multi-step Without Weight Factors FCS-MPC Control of Multi-level APF

Abstract

The multi-objective single-factor multi-step finite control set model predictive control (FCS-MPC) of active power filter (APF) proposed in this paper is suitable for multi-objective multi-level converter control. This method is applied to the three-level APF structure, which changes the traditional three-level FCS-MPC control method. The traditional three-level FCS-MPC includes four control targets, stable control of the DC side voltage, and the power grid harmonic currents generated under non-linear loads and balance the capacitor voltage on the DC side. This method mainly uses the redundant switching state of the three-level structure to achieve the balance of the voltage of the two capacitors on the DC side, instead of adding the weighting factors to the objective function in the traditional method, reduce the difficulty of target optimization caused by the selection of weight factors. Based on multi-step prediction, the power feedback control on the DC side is added to increase the DC side reaction speed, eliminate the influence of uncertainty, and have better dynamic performance. Comparing the simulation experiment of the method, the results show that the method has good followability, can compensate the harmonics of the power grid, reduce the harmonic content to less than 5%, and balance the DC side capacitor voltage.