Step Based Control Algorithm for Grid Interactive PV-Battery System Under Abnormal Grid Conditions using Fuzzy Logic Based MPPT

Abstract— This topology describes the single-phase grid connected solar PV (Photovoltaic) system with seamless power transfer capability. This system provides uninterrupted power supply under abnormal grid conditions. PV Battery system comprises of two stages. First stage involving PV array boost converter along with a battery energy storage-bidirectional converter that is integrated at dc-link and another is voltage source converter (VSC). A self-adjustable step-based control is introduced for the VSC. This estimates the real power reflecting portion of the load current in order to show the features of the PV-battery system. Several algorithms of MPPT control are developed based on various methods, such as Perturb and Observe, Incremental Conductance, Fractional Open-Circuit Voltage and Fractional Short-Circuit Current algorithms. To increase the utilisation of solar PV system improvement is done using different controllers. Here we have implemented the fuzzy logic based MPPT method to extract maximum power from the PV. Simulation studies are carried out in MATLAB Simulink. The performance of the grid interactive PV battery system using fuzzy logic based MPPT is found more efficient when compared to the incremental conductance MPPT.