Model-based Predictive Direct Power Control of Single Phase Active Front End Converter using a Finite Control Set

The paper proposes a Model-based Predictive Direct Power Control (MP-DPC) of Single-Phase Active Front End converter operating under Unity Power Factor using a Finite Control Set (FCS). The values of One-Sample Ahead (OSA) grid current have been calculated using the discrete-time model of the system. Based on the possible switching states of the converter, the Two-Sample Ahead (TSA) grid currents and the associated power drawn from the grid for each switching state are calculated. The peak current reference generated from the outer DC link voltage control loop is used to estimate the reference power drawn from the grid. The optimal switching state, selected according to the error minimization function is applied to the converter in the next switching instant. The power drawn by the converter from the grid is controlled directly leading to faster transient response of the converter compared to Instantaneous Current Control schemes (ICC). The elimination of linear current controllers in the inner loop is an added advantage. The results from tests conducted on a 5-kW laboratory set-up have been presented to validate the proposed control algorithm.