Optimized controllers design for incorporating renewable energy technologies based on PV-DC microgrid integrated to public grid

This paper presents the integration of renewable energy technologies in a DC microgrid, incorporating photovoltaic (PV) and battery systems connected to the grid. This paper focuses on strategies of maximum power point tracking (MPPT) of PV system by using conventional and optimized controllers to provide reliable system of high quality electricity. Energy storage system has been utilized to achieve an optimal utilization and operation efficiency by applying suitable power electronics to interface different sources and loads to the grid. The control systems have been applied to generate the maximum power from renewable power sources and maintain the stable operation of DC grids under variable supply and demand conditions. The main concept of this controlled microgrid is to enhance the operation of distributed generations (DGs) to produce a DC voltage and keep balance between the active and reactive power requirements with other system components. Furthermore, the maximum power from PV module has been by boosting the generated DC voltage to a suitable level. VSI controller comprises of voltage and current control systems to control the frequency and to control current waveform as well as the output power to the grid. Different controllers have been applied by MPPT of PV system such as PI controller and fuzzy controller. PI controller has been applied because of its simplicity, ease of implementations and less complexity. But, due to the poor performance of conventional controllers, fuzzy controller systems are applied when have appropriate fuzzy rules to reduce the overshoot, improve performance and produce accurate results. A complete MATLAB/SIMULINK model of the whole system, including the boost converter controlled by the incremental conductance MPPT algorithm with different controllers to enhance energy efficiency, is presented to obtain simulation results. The results demonstrate the best performance in comparison between fuzzy control and conventional PI control systems.