Energy management of photovoltaic and battery energy storage based grid tied three level inverter system

With the increase in energy crisis and pollution, the solar energy terms out to be an alternative solution. This paper proposes a system comprising of PV array and a Li-ion battery connected to the grid through a three phase, three level diode clamped inverter. A power flow algorithm is proposed which determines the modes of operation of the system during climatic variations. The inverter is controlled by using synchronous reference frame technique that controls the active power injection into the grid and also regulates the dc-link voltage to a constant value. PLL (Phase locked loop) technique is used to detect the phase angle of the grid voltage. The inverter injects current into the grid in phase with the voltage to get desired unity power factor operation. The system is studied under different scenarios and verified by the result of the simulation.