EE678A - Power Electronics In Solar Photovoltaic Systems

Introduction to Motivation. Solar Radiations: Composition, spectrum Air Mass, optimal angle of panel, solar constant, India’s solar resource. Solar PV cell: Direct vs Indirect Band, Generation of carriers, drift and diffusion currents, P-N Junction, I-V characteristics of cell, fill factor, maximum short circuit current, maximum open circuit voltage, efficiency, fundamental and technological losses, electrical model of cell, effect of series and shunt resistances, optical losses and minimization techniques, Soloar PV Module: Series/parallel connection, I-V characteristics of module, mismatching due to temperature and shading, Bypass and blocking diodes, overview of PV module fabrication, I-V equation of module, standard test conditions, Review of dc-dc buck & boost converters Maximum power point tracking: motivation, power extracted with resistive load, implementing variable resistance load, tracking using dc-dc converter, direct vs indirect control, fractional open circuit voltage control, hill climbing method and issues, incremental conductance method, mppt extraction efficiency, effect of voltage ripple on efficiency. Battery charging: types and characteristics of battery, comparison of charging characteristics, popular technique for charging lead acid battery, charging using dc-dc converter, PV charging circuits, stable operation of chargers. Solar Inverters: standalone vs grid connected, days of autonomy, payback period, Parity, grid feeding inverter, central inverters circuits, string inverters, earth leakage current, module inverters, features of grid feeding inverter, relevant standards, islanding.