Control of a Three-phase Off-Grid Inverter for Photovoltaic Systems Applications

Abstract

This paper presented a model predictive control (MPC) strategy as used in photovoltaic (PV) systems applications to control a three-phase off-grid inverter. The PVs model was used in this study to investigate the system performance when power is supplied to a resistive-inductive load (RL-load). The proposed strategy is to handle the output current for the three-phase, off-grid inverter with an RL-load. An assessment is given of the robustness of the control strategy under variable DC voltages, and as required for photovoltaic systems applications, by measuring the Total harmonic distortion (THD) and tracking behaviour of the reference currents; this was done for all DC voltage values. The system is tested as well with different sampling times to check the tracking behavior at designed values. The simulations and result analyses are carried out using MATLAB/Simulink to test the effectiveness and robustness of MPC for three-phase off-grid inverter with resistive-inductive load supplied by a PV system. The simulation results indicated that the proposed control algorithms achieved both high performance and a high degree of robustness in photovoltaic systems applications.