MODELLING AND SIMULATION OF STANDALONE PV SYSTEM WITH BATTERY STORAGE

Abstract

As the population is increasing and quality of life is becoming better, demand for energy is also increasing and fossil fuel resources are depleting. Moreover, the use of fossil fuel causes pollution and global warming. These concerns leads to the worldwide adoption of renewable sources of energy viz. solar energy, wind energy, geothermal energy etc. Renewable energy sources do not cause harm to the environment and can be used repeatedly. Solar energy is the most widely used renewable energy source. Solar PV array is the most critical part of a standalone PV system. In this work modelling and design of standalone PV system is studied. Solar energy produced by the photovoltaic array varies, as atmospheric conditions changes. MPPT controllers are used to obtain the maximum power from the PV array under various atmospheric conditions. These controllers work on Maximum power point tracking algorithms (MPPT). There are many MPPT algorithms described in literature. In this work five such algorithms viz. Fractional open circuit voltage, Perturbation and Observe, Incremental conductance, Fuzzy logic and Adaptive neuro-fuzzy Inference system(ANFIS) MPPT algorithms has been studied and a comparative analysis is presented. PV array works only when there is sunlight. So during night or cloudy or rainy conditions PV array does not provide required power. For providing the power under these conditions energy storage systems viz. ultra-capacitors, batteries etc. are used. In this work batteries as energy storage element is studied. The batteries in standalone PV system are charged during the day and provide power to the load at night. In this work battery charging scheme for PV system is designed and analysed. To further get an insight about battery charging, a battery charging scheme using AC supply is designed. AC battery chargers find applications in Electric vehicles, households etc.