Modeling and simulation of a SEPIC converter based photovoltaic system with battery energy storage

The variability and intermittency associated with the production of electricity by photovoltaic (PV) systems pose unique challenges to power systems engineers. Overcoming these challenges requires the use of computer models that accurately simulate the behavior of such systems. There is a dearth of such reliable and accurate models for PV systems study. This paper develops models for an integrated PV system which comprises the PV array, the SEPIC (single ended primary inductance converter) converter, bidirectional dc-dc converter, the inverter, and battery energy storage system using Matlab/Simulink. Control systems for maximum power point tracking and battery charge/discharge are implemented and used for simulations to study: 1) the response of the system to the ever-changing environmental variables, 2) the ability to track the maximum power point, and 3) the role of the battery energy storage in the mitigation of voltage and power oscillations. The simulation results are presented and discussed.