Low Frequency Finite Set Model Predictive Control for Seven-Level Modified Packed U-Cell Rectifier

Abstract

In this paper, a finite set model predictive control (FSMPC) with low switching frequency is designed for a modified seven-level Packed U-Cell (PUC) converter to work in rectifier mode of operation. In the proposed FSMPC, a cost function is derived by the use of the modified rectifier dynamic equations to choose a switching vector with the minimum cost for each sampling time so as the switching frequency is minimized. The single control loop of proposed FSMPC consisted of suitable controllable parameters are achieved by the accurate mathematical-based analyses of proposed 3D curves. The 3D curves are driven by the use of a proportional cost function as well as the dynamic behaviors of rectifier. The developed MPC scheme has been tested on the modified seven-level PUC rectifier by simulation and experimental analyses to validate the sinusoidal grid current with very low THD, unity power factor, and output DC voltages with negligible fluctuations.