Application of the Voltage Control Technique and MPPT of Stand-alone PV System with Storage

To provide a stable operation of a standalone microgrid based on the photovoltaic system in the most efficient way, various mechanisms and control strategies need to be engaged simultaneously. Modeling, simulation, and analysis of the microgrid system composed of PV generator, battery energy storage system (BESS), and DC/AC converter are presented in the paper. The PV generator operates in maximum power point (MPP) mode, while the BESS is deployed to enable power flow between the storage and consumers using the charge/discharge cycle of the battery. The maximum power point tracking (MPPT) control at the PV side, combined with battery control, is obtained by Perturb and Observe (P&O) and Fuzzy Logic Control (FLC) algorithms. Simulation based voltage control strategy is performed by using both DC/DC buck-boost converter and DC/AC converter with aim to obtain stable voltage for different power inputs. Modeling and simulations are performed in MATLAB/Simulink software. It is demonstrated that proposed methods ensure a stable microgrid operation and PV system operation in MPP mode. Both MPPT algorithms, P&O and FLC, provided accurate responses with very high efficiency above 95%.