Finite-Set Model Predictive Control of an Asymmetric Cascaded H-bridge photovoltaic inverter

Abstract

This paper presents a Finite-Set Model Predictive Control (FS-MPC) method adapted for an Asymmetric and Cascaded H-bridge Photovoltaic inverter (ACHB). This advanced control approach is designed to: Ensure an independent Maximum Power Point Tracking (MPPT), Synthesize at the inverter output a sinusoidal multistep PWM waveform, and provide an output current with unity power factor and low harmonic distortion. ACHB seems to be a perfect candidate for Photovoltaic systems. However, the control of such kind of converters is quite a challenging task. On the other hand, FS-MPC has achieved great popularity due to the ease with which the constraints, nonlinearities, and switching actions can be included in the controller formulation.Classical approach to tune the FS-MPC parameters is not fruitful for an ACHB. In this concern, we propose, new and dynamic, parameters for the FS-MPC algorithm. This approach is evaluated under different operating conditions including robustness tests.Results provide that the proposed FS-MPC method features a great flexibility and control potential.